A simulation method and system for deep water explosion impact resistance of a deep diving underwater vehicle

Abstract

The application provides a simulation method and system for deep water explosion impact resistance of a large-depth underwater vehicle, and the method comprises the following steps: obtaining underwater vehicle external geometric data and target structure region, and obtaining structure material parameters; calculating a deep diving static water pressure, an equivalent static pressure distribution of the target structure region, and establishing a prototype simulation model and a scale-down test model; performing a test to obtain simulated structure surface pressure, simulated structure strain time curve, simulated bubble motion trajectory and scale-down strain data; based on the above data, constructing a static water pressure term, an impact wave and a bubble pulsation pressure time term, and superimposing and constructing a joint load simulation model, and then obtaining an error, and if the condition is met, the simulation is completed. The simulation method for deep water explosion impact resistance of the large-depth underwater vehicle can dynamically couple high static water pressure, underwater explosion shock wave and bubble pulsation, so as to realize precise simulation of the deep water explosion impact load resistance of the large-depth underwater vehicle structure.

Description

Technical Field

[0001] This invention relates to the field of deep-sea explosion impact technology for deep-sea submersibles, and in particular to a simulation method and system for resistant deep-sea explosion impact to deep-sea submersibles. Background Technology

[0002] Deep-water explosion impact is one of the most severe threats faced by deep-sea submersibles. The powerful explosive force can not only damage the submersible's structure and cause equipment failure, but also endanger the lives of the crew. Therefore, research and design for deep-water explosion impact resistance of deep-sea submersible structures is a core issue in ensuring the safety of submersibles and improving their combat and survivability. In the field of deep-water explosion impact resistance research and design for deep-sea submersible structures, some relatively mature technologies and methods have been developed over many years. Among these, existing technologies mainly use a simplified model of "static pressure preloading and step-by-step impact load application" to simulate the scenario of an submersible being subjected to an explosion impact in a deep-water environment. Specifically, when designing and analyzing the impact resistance of the submersible structure, the effect of static water pressure is considered separately. The static water pressure borne by the submersible at different diving depths is calculated and applied as a preload to the submersible structure model. Then, the impact load generated by the underwater explosion is considered separately to determine the magnitude, direction, and duration of the impact load. Subsequently, the load is applied in stages to the structural model that has already undergone hydrostatic pressure preload, and the dynamic response and shock resistance of the underwater vehicle structure under this staged loading condition are analyzed. In practical engineering applications, this technique is widely used in the preliminary design and simulation analysis of underwater vehicle structures.

[0003] Under the current technological background, with the continuous improvement of the requirements for the resistance to deep-water explosion impact of deep-diving underwater vehicles, the limitations of existing technologies are becoming increasingly prominent, mainly in the following aspects: First, the dynamic coupling effect of high hydrostatic pressure, underwater explosion shock wave, and bubble pulsation is not considered, making it impossible to accurately quantify the modulation mechanism of hydrostatic pressure on shock wave propagation characteristics (such as wave velocity and attenuation rate) and structural dynamic response at deep diving depths. This leads to inaccurate predictions of the underwater vehicle structure's response under actual deep-water explosion impact environments. In actual deep-water explosion environments, the three loads—high hydrostatic pressure, underwater explosion shock wave, and bubble pulsation—do not act independently on the underwater vehicle structure but rather have a complex dynamic coupling relationship. Hydrostatic pressure alters the water body... The physical properties of water affect the propagation speed and attenuation of shock waves. For example, under high pressure, the density of water increases, which may accelerate the propagation speed of shock waves and change their attenuation rate. Furthermore, there is an interaction between shock waves and bubble pulsations; the secondary pressure pulses generated by bubble pulsations further affect the structural response. Current technology considers these three loads separately, neglecting their dynamic coupling, thus failing to accurately reflect the actual situation and leading to deviations in the prediction of underwater vehicle structural responses. Secondly, the lack of an effective method for equivalent conversion of combined loads makes it impossible to reproduce the high-pressure environment at great depths in the laboratory, hindering accurate assessment of the shock resistance performance of underwater vehicle structures through land-based tests. Optimized design has limited the research and development of related technologies. The deep-sea environment in which deep-sea submersibles operate is extremely high-pressure; for example, at depths of several thousand meters, hydrostatic pressure can reach hundreds of atmospheres. Completely replicating such a high-pressure environment in the laboratory requires not only extremely complex and expensive experimental equipment but also presents immense technical challenges. Current technologies lack effective methods for equivalent conversion of combined loads, making it impossible to convert combined loads under the high-pressure environment of deep-sea submersibles into load conditions achievable in the laboratory. This forces researchers to rely solely on theoretical calculations and numerical simulations. However, theoretical calculations and numerical simulations often involve certain assumptions and simplifications, and the accuracy of their results requires experimental verification. Therefore, the lack of effective experimental methods hinders the development of related technologies. The research is difficult to conduct in depth, limiting the improvement and optimization of the impact resistance performance of underwater vehicle structures. Thirdly, the traditional simplified model of "phased application of hydrostatic preload and impact load" differs significantly from the complex actual load conditions in finite element impact simulations, resulting in low design confidence and potentially making the designed underwater vehicle structure unable to meet the requirements for resisting deep-water explosion impacts in practical applications. In actual deep-water explosion impact processes, high hydrostatic pressure, shock waves, and bubble pulsation act simultaneously on the underwater vehicle structure, and their interactions are dynamic and real-time. The traditional simplified model, which first applies hydrostatic preload and then applies impact loads in stages, differs from the actual load process and cannot fully represent the realism of the process.In finite element simulations, such discrepancies in the model can lead to inconsistencies between the calculated structural stress, deformation, and other responses and the actual conditions. Designs based on these simulation results will inevitably have low confidence levels. Once the designed underwater vehicle structure is deployed in real-world applications, it may be damaged by actual deep-sea explosions due to insufficient structural strength and poor impact resistance, thus failing to guarantee the safety of the underwater vehicle. Summary of the Invention

[0004] The present invention aims to provide a simulation method and system for the resistance of deep-sea submersible vehicles to deep-sea explosion impact, in order to solve the above-mentioned technical problems. The simulation method for the resistance of deep-sea submersible vehicles to deep-sea explosion impact provided by the present invention can dynamically couple high hydrostatic pressure, underwater explosion shock wave and bubble pulsation, thereby achieving accurate simulation of the resistance of deep-sea explosion impact load on the structure of deep-sea submersible vehicles.

[0005] To address the aforementioned technical problems, this invention provides a simulation method for simulating the impact resistance of deep-sea submersibles against deep-sea explosions. This method is applied to a simulation system for simulating the impact resistance of deep-sea submersibles against deep-sea explosions, and includes: Acquire the geometric data of the underwater vehicle's external shape and the target structural region of the underwater vehicle, and obtain the structural material parameters based on the target structural region of the underwater vehicle; Based on the underwater vehicle's external geometric data, preset diving depth range, and target structure region of the underwater vehicle, the hydrostatic pressure corresponding to several diving depths and the equivalent hydrostatic pressure distribution of the target structure region of the underwater vehicle are calculated, and a prototype simulation model and a scaled-down test model are established. The external experimental chamber is controlled to conduct tests on the scaled-down test model to obtain the time history curves of pressure on the simulated structure surface, the time history curves of strain on the simulated structure, the trajectory of simulated bubbles, and the scaled-down strain data. Based on the simulated surface pressure time history curve and the hydrostatic pressure corresponding to several depths, the peak pressure of the shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the explosion source distance corresponding to the peak pressure of the shock wave, the shock wave distance attenuation parameter, the coupling coefficient of the charge medium and the correlation parameter of the peak pressure of the explosion shock wave are obtained, and the initial hydrostatic pressure term is constructed based on the hydrostatic pressure corresponding to several depths. Based on the simulated structural surface pressure time history curve, the peak pressure correlation parameters of the explosion shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the blast source distance corresponding to the peak pressure of the shock wave, the coupling coefficient of the charge medium, and the shock wave distance attenuation parameters, an initial shock wave pressure time history term is constructed. Based on the simulated bubble motion trajectory, the simulated structural surface pressure time history curve, the hydrostatic pressure corresponding to several depths, the explosion source distance corresponding to the peak pressure of the shock wave, and the charge equivalent corresponding to the peak pressure of the shock wave, an initial bubble pulsation pressure time history term is constructed. The initial hydrostatic pressure term, the initial shock wave pressure time history term, and the initial bubble pulsation pressure time history term are superimposed to construct a joint load spectrum. This joint load spectrum is then loaded into the prototype simulation model to obtain the joint load simulation model. The joint load simulation model is then used to simulate the joint load simulation model and obtain prototype strain data. Based on the prototype strain data and the scaled-down strain data, the strain data error is obtained. If the strain data error meets the simulation reliability conditions, the simulation of the deep-sea submersible's resistance to deep-water explosions is completed.

[0006] In the above scheme, by calculating the hydrostatic pressure corresponding to several diving depths and the equivalent hydrostatic pressure distribution of the target structural region of the underwater vehicle, and establishing a prototype simulation model and a scaled-down test model, a simulation carrier that fits the actual deep-water environment of the deep-diving underwater vehicle and a scaled-down test model capable of conducting actual experiments are constructed, providing a scenario framework for the dynamic coupling of the three loads. Next, by acquiring the time history curves of the simulated structural surface pressure, the time history curves of the simulated structural strain, the simulated bubble motion trajectory, and scaled-down strain data, raw data support is provided for the subsequent quantification of the dynamic characteristics and interaction mechanisms of the three loads. Simultaneously, the obtained scaled-down strain data can be used to verify the effectiveness of the deep-water explosion resistance simulation for the deep-diving underwater vehicle. Then, based on the time history curves of the simulated structural surface pressure and the hydrostatic pressure corresponding to several diving depths, the modulation of the shock wave propagation characteristics by hydrostatic pressure is realized, and an initial hydrostatic pressure term is constructed, providing the basic load components for the construction of the joint load spectrum. Subsequently, by constructing the initial shock wave pressure time history term, the modulation effect of hydrostatic pressure on the shock wave can be quantified, and the time history and pressure amplitude change of the shock wave from the explosion source to the surface of the underwater vehicle structure can be fully restored, providing dynamic load components that conform to actual working conditions for the joint load spectrum.

[0007] Next, by integrating the simulated bubble motion trajectory, the simulated structural surface pressure time history curve, the simulated structural surface pressure time history curve, the hydrostatic pressure corresponding to several diving depths, the explosion source distance corresponding to the peak pressure of the shock wave, and the charge equivalent corresponding to the peak pressure of the shock wave, the dynamic coupling between bubble pulsation, hydrostatic pressure, and the explosion parameters of the underwater explosion shock wave was realized. The resulting initial bubble pulsation pressure time history term provides dynamic load components for the joint load spectrum. Finally, by constructing a combined load simulation model, high hydrostatic pressure, underwater explosion shock waves, and bubble pulsation can be dynamically coupled. Through simulation using the combined load simulation model, the stress process of the underwater vehicle structure under actual complex combined loads can be simulated. The obtained prototype strain data can be calculated with scaled strain data to verify the effectiveness of the equivalent conversion of the combined load spectrum and the reliability of the simulation model, i.e., to determine whether the simulation reliability conditions are met. If the simulation reliability conditions are met, it indicates that the constructed combined load simulation model can accurately characterize the load process and structural response law of the deep-diving underwater vehicle in the actual deep-water explosion environment, thus realizing the simulation of the deep-diving underwater vehicle's resistance to deep-water explosions.

[0008] Furthermore, it also includes: If the strain data error does not meet the simulation reliability conditions, the joint load spectrum is reconstructed and loaded into the prototype simulation model to obtain the joint load simulation model. The joint load simulation model is then re-simulated to update the prototype strain data. Based on the prototype strain data and the scaled-down strain data, the strain data error is obtained until the strain data error meets the simulation reliability conditions.

[0009] In the above scheme, by reconstructing the joint load spectrum when the strain data error does not meet the simulation reliability conditions, the parameter deviations of high hydrostatic pressure, underwater explosion shock wave, and bubble pulsation in the dynamic coupling process can be corrected. This ensures that the obtained joint load simulation model can closely match the load action process and structural response law of the deep-diving underwater vehicle in the actual deep-water explosion environment, providing accurate load input for updating the prototype strain data. Then, by updating the prototype strain data and scaled-down strain data to obtain the strain data error, until the strain data error meets the simulation reliability conditions, it can be ensured that the joint load simulation model at this time can reflect the interaction of high hydrostatic pressure, underwater explosion shock wave, and bubble pulsation, as well as the actual stress response of the underwater vehicle structure. This achieves high-precision and high-reliability simulation of the deep-diving underwater vehicle's resistance to deep-water explosions, avoiding simulation result distortion due to insufficient fitting accuracy.

[0010] Furthermore, based on the underwater vehicle's external geometric data, a preset diving depth range, and the target structural region of the underwater vehicle, the calculation of hydrostatic pressure at several diving depths and the equivalent hydrostatic pressure distribution of the target structural region of the underwater vehicle, and the establishment of a prototype simulation model and a scaled-down test model, includes: Based on a preset depth range, obtain the hydrostatic pressure corresponding to several depths; Based on the target structure region of the underwater vehicle and the hydrostatic pressure corresponding to several diving depths, the equivalent hydrostatic pressure distribution of the target structure region of the underwater vehicle is calculated. Based on the underwater vehicle's external geometric data, hydrostatic pressure corresponding to several diving depths, preset hydrostatic pressure similarity ratio, preset geometric similarity ratio, structural material parameters, preset material similarity ratio, preset explosive equivalent, preset detonation center distance range, preset explosive type, and preset explosive equivalent similarity ratio, a prototype simulation model and a scaled-down experimental model are established.

[0011] In the above scheme, by obtaining the hydrostatic pressure corresponding to several diving depths within a preset diving depth range, the hydrostatic pressure corresponding to different depths of the underwater vehicle in a diving environment can be clearly defined, providing basic data that fits the actual working conditions for subsequent calculation of equivalent hydrostatic pressure distribution and establishment of a prototype simulation model. Next, the equivalent hydrostatic pressure distribution of the underwater vehicle's target structural region is calculated using the hydrostatic pressure corresponding to several diving depths. The obtained equivalent hydrostatic pressure distribution can accurately characterize the spatial distribution differences of hydrostatic pressure in different parts of the underwater vehicle's target structure, thus providing a boundary basis for the precise spatial application of combined loads. Then, by integrating hydrostatic pressure, preset hydrostatic pressure similarity ratio, preset geometric similarity ratio, structural material parameters, preset material similarity ratio, preset explosive equivalent, preset detonation center distance range, preset explosive type, and preset explosive equivalent similarity ratio corresponding to several diving depths, it is possible to construct a prototype simulation model and a scaled-down test model that meets the scaling equivalence criterion. This enables accurate replication of the actual deep-water explosion environment of deep-diving underwater vehicles, providing a reliable platform for dynamic coupling tests of three loads: high hydrostatic pressure, underwater explosion shock wave, and bubble pulsation.

[0012] Furthermore, based on the simulated surface pressure time history curve and the hydrostatic pressure corresponding to several depths, the peak shock wave pressure, the charge equivalent corresponding to the peak shock wave pressure, the explosion source distance corresponding to the peak shock wave pressure, the shock wave distance attenuation parameter, the charge medium coupling coefficient, and the correlation parameter of the peak explosion shock wave pressure are obtained. An initial hydrostatic pressure term is constructed based on the hydrostatic pressure corresponding to several depths, including: Based on the simulated surface pressure time history curve and the preset detonation center distance range, the peak pressure of the shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, and the detonation source distance corresponding to the peak pressure of the shock wave are extracted. The peak pressure of the shock wave and the corresponding explosion source distance are fitted to obtain the fitting coefficient of the peak pressure of the first hydrostatic shock wave and the fitting coefficient of the peak pressure of the second hydrostatic shock wave. Based on the fitting coefficient of the peak pressure of the first hydrostatic shock wave, the fitting coefficient of the peak pressure of the second hydrostatic shock wave, and the hydrostatic pressure corresponding to several depths, the shock wave distance attenuation parameter is obtained. The coupling coefficient of the charge medium is obtained by fitting the preset explosive type and preset medium environment; By fitting the peak pressure of the shock wave and the corresponding charge equivalent, the correlation parameters of the peak pressure of the explosion shock wave are obtained. The initial hydrostatic pressure term is constructed based on the hydrostatic pressure corresponding to several depths.

[0013] In the above scheme, by simulating the time history curve of the pressure on the structural surface and using a preset range of detonation center distance, the peak pressure of the shock wave, the equivalent charge of the peak pressure, and the detonation source distance corresponding to the peak pressure are extracted. This clarifies the core characteristic parameters of the underwater explosion shock wave load, providing basic data for the subsequent quantification of the hydrostatic pressure modulation mechanism. Next, the peak pressure and the corresponding detonation source distance are fitted to obtain the fitting coefficients for the first and second hydrostatic pressure peak pressure shock waves, establishing a quantitative correlation between the peak pressure and the detonation source distance, laying the foundation for the subsequent derivation of the shock wave distance attenuation parameters. Then, using the fitting coefficients for the first and second hydrostatic pressure peak pressure shock waves and the hydrostatic pressure corresponding to several depths, the shock wave distance attenuation parameters are obtained. This quantifies the modulation effect of hydrostatic pressure on the shock wave propagation attenuation characteristics, improving the multi-dimensional description of the shock wave propagation law in deep-sea environments. Subsequently, the coupling coefficient between the explosive type and the underwater medium is obtained by fitting the preset explosive type and the preset medium environment. This clarifies the interaction characteristics between the explosive type and the underwater medium, providing key parameters for constructing the initial shock wave pressure time history term. Next, by fitting the peak shock wave pressure and the corresponding explosive equivalent, a quantitative relationship between the peak shock wave pressure and the explosive equivalent is established, obtaining the correlation parameters of the peak shock wave pressure, ensuring an accurate description of the shock wave load under different explosive equivalent explosion conditions. Finally, an initial hydrostatic pressure term is constructed using the hydrostatic pressure corresponding to several depths, providing the basic load components for constructing the joint load spectrum.

[0014] Furthermore, the initial shock wave pressure time history term is constructed based on the simulated structural surface pressure time history curve, the peak pressure correlation parameters of the explosion shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the blast source distance corresponding to the peak pressure of the shock wave, the coupling coefficient of the charge medium, and the shock wave distance attenuation parameters, including: Based on the peak pressure correlation parameters of the explosion shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the blast source distance corresponding to the peak pressure of the shock wave, the preset distance similarity ratio, the coupling coefficient of the charge medium, and the shock wave distance attenuation parameters, the peak pressure parameters of the hydrostatic pressure modulated shock wave are calculated. Based on the simulated surface pressure time history curve, the charge equivalent corresponding to the peak pressure of the shock wave, the explosion source distance corresponding to the peak pressure of the shock wave, and the similarity ratio of the preset explosive equivalent, the shock wave decay time constant is obtained. Based on the peak pressure parameters of the hydrostatic modulated shock wave and the shock wave decay time constant, an initial shock wave pressure time history term is constructed.

[0015] In the above scheme, by using parameters related to the peak pressure of the explosion shock wave, the charge equivalent corresponding to the peak pressure, the blast source distance corresponding to the peak pressure, the preset distance similarity ratio, the charge medium coupling coefficient, and the shock wave distance attenuation parameters, the dynamic influence of hydrostatic pressure on the peak pressure of the shock wave can be quantified. This prevents the neglect of the modulation effect of hydrostatic pressure on the shock wave, and the obtained hydrostatic pressure modulated peak pressure parameters of the shock wave can closely match the actual working conditions of deep-sea submersibles in deep-water explosions. Next, by simulating the time history curve of the structural surface pressure, the charge equivalent corresponding to the peak pressure of the shock wave, the blast source distance corresponding to the peak pressure of the shock wave, and the preset explosive equivalent similarity ratio, the shock wave attenuation time constant is obtained. This accurately captures the attenuation law of the shock wave under hydrostatic pressure, providing parameter support for the subsequent accurate construction of the initial shock wave pressure time history term and the complete reconstruction of the time dimension characteristics of the shock wave. Then, by modulating the peak pressure parameter of the shock wave and the attenuation time constant of the shock wave with hydrostatic pressure, the initial shock wave pressure time history term is constructed, which restores the pressure change process of the dynamic coupling between hydrostatic pressure and shock wave. This can provide dynamic load components that conform to the actual physical mechanism for the joint load spectrum, ensuring the accuracy of the deep-sea explosion simulation of the deep-sea submersible.

[0016] Furthermore, the initial bubble pulsation pressure time history term is constructed based on the simulated bubble motion trajectory, the simulated structural surface pressure time history curve, the hydrostatic pressure corresponding to several depths, the explosion source distance corresponding to the peak shock wave pressure, and the charge equivalent corresponding to the peak shock wave pressure, including: Based on the simulated bubble motion trajectory, the simulated structural surface pressure time history curve, the simulated structural surface pressure time history curve, the hydrostatic pressure corresponding to several diving depths, the explosion source distance corresponding to the peak pressure of the shock wave, and the charge equivalent corresponding to the peak pressure of the shock wave, the pulse period fitting parameters, the first pulse fitting parameters, the second pulse fitting parameters, the third pulse fitting parameters, the pulse damping time constant, and the pulse start time are calculated. Based on the first pulsating pulse fitting parameters, the second pulsating pulse fitting parameters, the third pulsating pulse fitting parameters, the pulsation period fitting parameters, the pulse damping time constant, the pulse start time, and the explosive equivalent similarity ratio, the initial bubble pulsating pressure time history term is constructed.

[0017] In the above scheme, by simulating the bubble motion trajectory, simulating the time history curve of the structural surface pressure, simulating the hydrostatic pressure at several depths, the explosion source distance corresponding to the peak pressure of the shock wave, and the charge equivalent corresponding to the peak pressure of the shock wave, the modulation effect of hydrostatic pressure on bubble pulsation can be quantified. The calculated pulsation period fitting parameters, first pulsation pulse fitting parameters, second pulsation pulse fitting parameters, third pulsation pulse fitting parameters, pulse damping time constant, and pulse start time provide parameter support for the construction of the initial bubble pulsation pressure time history term. Then, by using the first pulsation pulse fitting parameters, second pulsation pulse fitting parameters, third pulsation pulse fitting parameters, pulsation period fitting parameters, pulse damping time constant, pulse start time, and explosive equivalent similarity ratio, the dynamic process of the bubble under hydrostatic pressure modulation can be completely reproduced. The constructed initial bubble pulsation pressure time history term can realize the dynamic coupling between bubble pulsation, hydrostatic pressure, and the explosion parameters of the underwater explosion shock wave, and provide dynamic load components for the joint load spectrum, ensuring the integrity and accuracy of the deep-water explosion resistance simulation of the deep-diving underwater vehicle.

[0018] Furthermore, the calculation of the pulse period fitting parameters, first pulse fitting parameters, second pulse fitting parameters, third pulse fitting parameters, pulse damping time constant, and pulse start time based on the simulated bubble motion trajectory, simulated structural surface pressure time history curve, simulated structural surface pressure time history curve, hydrostatic pressure corresponding to several depths, explosion source distance corresponding to shock wave peak pressure, and charge equivalent corresponding to shock wave peak pressure, includes: Based on the simulated bubble motion trajectory, the bubble pulsation period is extracted; Based on the bubble pulsation period, the hydrostatic pressure corresponding to several diving depths, the charge equivalent corresponding to the peak pressure of the shock wave, and the similarity ratio of the explosive equivalent, the pulsation period fitting parameters are calculated. Based on the time history curve of the simulated structure surface pressure, the peak value of bubble pulsation pressure is extracted; Based on the hydrostatic pressure corresponding to the aforementioned depths, the preset reference pressure, the explosion source distance corresponding to the peak shock wave pressure, the charge equivalent corresponding to the peak shock wave pressure, the explosive equivalent similarity ratio, and the peak pressure of bubble pulsation, the first pulsation pulse fitting parameters, the second pulsation pulse fitting parameters, and the third pulsation pulse fitting parameters are obtained. Based on the simulated surface pressure time history curve, the pulse damping time constant and pulse start time are extracted.

[0019] In the above scheme, by simulating the bubble motion trajectory to extract the bubble pulsation period, the dynamic characteristics of the bubble under hydrostatic pressure can be accurately captured, providing basic data for the subsequent calculation of pulsation period fitting parameters. Next, by using the bubble pulsation period, the hydrostatic pressure corresponding to several depths, the charge equivalent corresponding to the peak shock wave pressure, and the explosive equivalent similarity ratio, the modulation effect of hydrostatic pressure and charge equivalent on the bubble pulsation period can be quantified, ensuring that the calculated pulsation period fitting parameters conform to the equivalence criterion of the explosive equivalent similarity ratio. Then, by simulating the pressure time history curve of the structural surface to extract the peak pressure of the bubble pulsation, key data can be provided for the calculation of the following pulsation pulse fitting parameters. Subsequently, by using hydrostatic pressure corresponding to several diving depths, preset reference pressure, the explosion source distance corresponding to the peak shock wave pressure, the charge equivalent corresponding to the peak shock wave pressure, the explosive equivalent similarity ratio, and the peak value of bubble pulsation pressure, the fitting parameters for the first, second, and third pulsation pulses were obtained. A quantitative correlation between the bubble pulsation amplitude and multiple influencing factors was established, ensuring the variation law of bubble pulsation pressure under different working conditions. This allows for an accurate description of bubble pulsation pressure under various working conditions, providing reliable support for constructing the bubble pulsation pressure time history term in the joint load spectrum. Finally, by simulating the pressure time history curve of the structural surface, the pulse damping time constant and pulse start time were extracted, providing parameter basis for the time dimension modeling of the bubble pulsation pressure time history term.

[0020] Further, the initial hydrostatic pressure term, the initial shock wave pressure time history term, and the initial bubble pulsation pressure time history term are superimposed to construct a joint load spectrum, and the joint load spectrum is loaded into the prototype simulation model to obtain a joint load simulation model. The joint load simulation model is then used to simulate the joint load simulation model and obtain prototype strain data. Based on the prototype strain data and the scaled-down strain data, the strain data error is obtained. If the strain data error meets the simulation reliability conditions, the simulation of the deep-sea submersible's resistance to deep-water explosions is completed, including: Based on the preset hydrostatic pressure similarity ratio and the initial hydrostatic pressure term, the first hydrostatic pressure term is obtained; based on the preset shock wave peak pressure similarity ratio and the initial shock wave pressure time history term, the first shock wave pressure time history term is obtained; based on the preset bubble pulsation pressure similarity ratio and the initial bubble pulsation pressure time history term, the first bubble pulsation pressure time history term is obtained. The first hydrostatic pressure term, the first shock wave pressure time history term, and the first bubble pulsation pressure time history term are superimposed to construct a joint load spectrum, and the joint load spectrum is loaded into the prototype simulation model to obtain the joint load simulation model. The combined load simulation model was simulated to obtain prototype strain data; Based on prototype strain data and scaled-down strain data, the strain data error is obtained. If the strain data error meets the simulation reliability conditions, the simulation of the deep-sea submersible's resistance to deep-sea explosions is completed.

[0021] In the above scheme, by obtaining the first hydrostatic pressure term, the first shock wave pressure time history term, and the first bubble pulsation pressure time history term, equivalent scaling of each load term is achieved, making the load parameters conform to the actual working conditions of the prototype deep-diving underwater vehicle, laying the foundation for constructing a realistic joint load spectrum. Next, by superimposing the first hydrostatic pressure term, the first shock wave pressure time history term, and the first bubble pulsation pressure time history term to construct a joint load simulation model, the dynamic coupling of high hydrostatic pressure, underwater explosion shock wave, and bubble pulsation can be achieved. This model is then loaded into the prototype simulation model to obtain the joint load simulation model, realizing the simulation reproduction of the dynamic coupling effect of high hydrostatic pressure, underwater explosion shock wave, and bubble pulsation, improving the consistency between the simulation model and the actual load application scenario. Subsequently, the first equivalent stress corresponding to the hydrostatic pressure is calculated using this joint load simulation model, providing data support that conforms to actual working conditions for subsequent fitting. Then, by simulating the combined load simulation model to obtain prototype strain data, the dynamic response of the deep-diving underwater vehicle structure under actual combined loads was obtained, providing data support for subsequent verification of simulation reliability and optimization of structural design. Subsequently, the obtained prototype strain data can be compared with scaled strain data to verify the effectiveness of the equivalent conversion of the combined load spectrum and the reliability of the simulation model, that is, to determine whether the strain data error meets the simulation reliability condition. If the simulation reliability condition is met, it indicates that the constructed combined load simulation model can accurately characterize the load process and structural response law of the deep-diving underwater vehicle in the actual deep-water explosion environment, thus realizing the simulation of the deep-diving underwater vehicle's resistance to deep-water explosions.

[0022] This invention provides a simulation system for the resistance of a deep-sea submersible to deep-water explosion impacts. Applied to the simulation method described above for the resistance of a deep-sea submersible to deep-water explosion impacts, the system includes a data acquisition module, a prototype simulation model construction module, a data acquisition module, a hydrostatic pressure term construction module, a shock wave pressure time history term construction module, a bubble pulsation pressure time history term construction module, and a simulation verification module. Specifically: The data acquisition module is used to acquire the geometric data of the underwater vehicle's shape and the target structural region of the underwater vehicle, and to acquire structural material parameters based on the target structural region of the underwater vehicle. The prototype simulation model construction module is used to calculate the hydrostatic pressure corresponding to several diving depths and the equivalent hydrostatic pressure distribution of the target structure area of ​​the underwater vehicle based on the underwater vehicle's external geometric data, preset diving depth range and underwater vehicle target structure area, and to establish a prototype simulation model and a scaled-down test model. The data acquisition module is used to control the external experimental chamber to conduct tests on the scaled-down test model in order to obtain the time history curve of the simulated structure surface pressure, the time history curve of the simulated structure strain, the simulated bubble motion trajectory, and the scaled-down strain data. The hydrostatic pressure term construction module is used to obtain the peak pressure of the shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the explosion source distance corresponding to the peak pressure of the shock wave, the shock wave distance attenuation parameter, the charge medium coupling coefficient and the correlation parameter of the peak pressure of the explosion shock wave based on the time history curve of the pressure on the simulated structure surface and the hydrostatic pressure corresponding to several depths, and to construct the initial hydrostatic pressure term based on the hydrostatic pressure corresponding to several depths. The shock wave pressure time history term construction module is used to construct an initial shock wave pressure time history term based on the simulated structure surface pressure time history curve, the peak pressure correlation parameters of the explosion shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the blast source distance corresponding to the peak pressure of the shock wave, the coupling coefficient of the charge medium, and the shock wave distance attenuation parameters. The bubble pulsation pressure time history term construction module is used to construct an initial bubble pulsation pressure time history term based on the simulated bubble motion trajectory, the simulated structural surface pressure time history curve, the simulated structural surface pressure time history curve, the hydrostatic pressure corresponding to several depths, the explosion source distance corresponding to the peak pressure of the shock wave, and the charge equivalent corresponding to the peak pressure of the shock wave. The simulation verification module is used to superimpose the initial hydrostatic pressure term, the initial shock wave pressure time history term, and the initial bubble pulsation pressure time history term to construct a joint load spectrum, and load the joint load spectrum into the prototype simulation model to obtain a joint load simulation model, so as to simulate the joint load simulation model and obtain prototype strain data; based on the prototype strain data and the scaled strain data, the strain data error is obtained. If the strain data error meets the simulation reliability condition, the simulation of the deep-sea submersible's resistance to deep-water explosion is completed.

[0023] This invention provides a simulation system for the resistance of deep-water explosions to deep-diving underwater vehicles. In practical applications, only a prototype simulation model construction module is needed. By calculating the hydrostatic pressure at several depths and the equivalent hydrostatic pressure distribution of the target structural region of the underwater vehicle, a prototype simulation model and a scaled-down test model are established. This constructs a simulation carrier that closely matches the actual deep-water environment of the deep-diving underwater vehicle and a scaled-down test model capable of conducting actual experiments, providing a scenario framework for the dynamic coupling of three loads. Next, a data acquisition module is used to acquire the time history curves of the simulated structural surface pressure, the time history curves of the simulated structural strain, the simulated bubble trajectory, and scaled-down strain data. This provides raw data support for the subsequent quantification of the dynamic characteristics and interaction mechanisms of the three loads. Simultaneously, the obtained scaled-down strain data can be used to verify the effectiveness of the deep-water explosion resistance simulation for deep-diving underwater vehicles. Then, a hydrostatic pressure term construction module is used. Based on the time history curves of the simulated structural surface pressure and the hydrostatic pressure at several depths, the modulation of the shock wave propagation characteristics by hydrostatic pressure is realized. Simultaneously, an initial hydrostatic pressure term is constructed, providing the basic load components for the construction of the joint load spectrum.

[0024] Subsequently, a shock wave pressure time history term construction module was employed. By constructing an initial shock wave pressure time history term, the modulation effect of hydrostatic pressure on the shock wave could be quantified, fully reconstructing the time history and pressure amplitude changes of the shock wave propagating from the explosion source to the surface of the underwater vehicle structure. This provided dynamic load components consistent with actual working conditions for the joint load spectrum. Next, a bubble pulsation pressure time history term construction module was employed. By fusing simulated bubble motion trajectories, simulated structural surface pressure time history curves, simulated structural surface pressure time history curves, hydrostatic pressure corresponding to several diving depths, explosion source distance corresponding to the peak shock wave pressure, and charge equivalent corresponding to the peak shock wave pressure, dynamic coupling between bubble pulsation, hydrostatic pressure, and the explosion parameters of the underwater explosion shock wave was achieved. The resulting initial bubble pulsation pressure time history term provided dynamic load components for the joint load spectrum. Finally, a simulation verification module was used. By constructing a joint load simulation model, high hydrostatic pressure, underwater explosion shock waves, and bubble pulsation could be dynamically coupled. Through simulation using the joint load simulation model, the stress process of the underwater vehicle structure under actual complex joint loads was simulated. The obtained prototype strain data could be calculated with scaled strain data to verify the effectiveness of the equivalent conversion of the joint load spectrum and the reliability of the simulation model, i.e., to determine whether the simulation reliability conditions are met. If the simulation reliability conditions are met, it indicates that the constructed joint load simulation model can accurately characterize the load process and structural response law of the deep-diving underwater vehicle in the actual deep-water explosion environment, thus realizing the simulation of the deep-diving underwater vehicle's resistance to deep-water explosions.

[0025] Furthermore, the simulation verification module also includes: If the strain data error does not meet the simulation reliability conditions, the joint load spectrum is reconstructed and loaded into the prototype simulation model to obtain the joint load simulation model. The joint load simulation model is then re-simulated to update the prototype strain data. Based on the prototype strain data and the scaled-down strain data, the strain data error is obtained until the strain data error meets the simulation reliability conditions.

[0026] In the above scheme, by reconstructing the joint load spectrum when the strain data error does not meet the simulation reliability conditions, the parameter deviations of high hydrostatic pressure, underwater explosion shock wave, and bubble pulsation in the dynamic coupling process can be corrected. This ensures that the obtained joint load simulation model can closely match the load action process and structural response law of the deep-diving underwater vehicle in the actual deep-water explosion environment, providing accurate load input for updating the prototype strain data. Then, by updating the prototype strain data and scaled-down strain data to obtain the strain data error, until the strain data error meets the simulation reliability conditions, it can be ensured that the joint load simulation model at this time can reflect the interaction of high hydrostatic pressure, underwater explosion shock wave, and bubble pulsation, as well as the actual stress response of the underwater vehicle structure. This achieves high-precision and high-reliability simulation of the deep-diving underwater vehicle's resistance to deep-water explosions, avoiding simulation result distortion due to insufficient fitting accuracy. Attached Figure Description

[0027] Figure 1 A flowchart illustrating a simulation method for resisting deep-sea explosion impacts in a deep-sea submersible vehicle, as provided in an embodiment of the present invention; Figure 2 This is an architecture diagram of a simulation system for resisting deep-sea explosion impacts on a deep-sea submersible, as provided in an embodiment of the present invention. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] This embodiment provides a simulation method for a deep-sea submersible to withstand the impact of deep-sea explosions. Please refer to the flowchart for details. Figure 1 A simulation system for resisting deep-sea explosions in a deep-sea submersible includes: Step S1: Obtain the geometric data of the underwater vehicle's shape and the target structural region of the underwater vehicle, and obtain the structural material parameters based on the target structural region of the underwater vehicle; Step S2: Based on the underwater vehicle's external geometric data, preset diving depth range, and target structure region of the underwater vehicle, calculate the hydrostatic pressure corresponding to several diving depths and the equivalent hydrostatic pressure distribution of the target structure region of the underwater vehicle, and establish a prototype simulation model and a scaled-down test model. Step S3: Control the external experimental chamber to conduct tests on the scaled-down test model to obtain the time history curve of the simulated structure surface pressure, the time history curve of the simulated structure strain, the simulated bubble motion trajectory, and the scaled-down strain data. Step S4: Based on the simulated surface pressure time history curve and the hydrostatic pressure corresponding to several depths, obtain the peak pressure of the shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the explosion source distance corresponding to the peak pressure of the shock wave, the shock wave distance attenuation parameter, the charge medium coupling coefficient and the correlation parameter of the peak pressure of the explosion shock wave, and construct the initial hydrostatic pressure term based on the hydrostatic pressure corresponding to several depths. Step S5: Based on the simulated structure surface pressure time history curve, the peak pressure correlation parameters of the explosion shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the explosion source distance corresponding to the peak pressure of the shock wave, the coupling coefficient of the charge medium, and the shock wave distance attenuation parameters, construct the initial shock wave pressure time history term; Step S6: Based on the simulated bubble motion trajectory, the simulated structural surface pressure time history curve, the hydrostatic pressure corresponding to several depths, the explosion source distance corresponding to the peak pressure of the shock wave, and the charge equivalent corresponding to the peak pressure of the shock wave, construct the initial bubble pulsation pressure time history term; Step S7: Superimpose the initial hydrostatic pressure term, the initial shock wave pressure time history term, and the initial bubble pulsation pressure time history term to construct a joint load spectrum. Load the joint load spectrum into the prototype simulation model to obtain the joint load simulation model. Simulate the joint load simulation model to obtain prototype strain data. Based on the prototype strain data and the scaled-down strain data, obtain the strain data error. If the strain data error meets the simulation reliability conditions, the simulation of the deep-sea submersible's resistance to deep-water explosion is completed.

[0030] In this embodiment, the external geometric data and target structural regions of a certain type of deep-diving underwater vehicle to be simulated are first obtained. Specifically, the target structural regions refer to the connection points between the pressure hull and the bulkhead, the reinforced sections of hull openings, or locally reinforced areas. Then, structural material parameters are obtained based on the target structural regions. For example, if the structural material is high-strength alloy steel, the structural material parameters are set according to the parameters for high-strength alloy steel, such as density. elastic modulus The Poisson's ratio is 0.3, and the yield strength is 800 MPa. Then, by calculating the hydrostatic pressure and equivalent hydrostatic pressure distribution of the target structural region of the underwater vehicle at several depths within a preset depth range, a prototype simulation model and a scaled-down test model were established. This constructed a simulation carrier that closely matches the actual deep-water environment of the deep-diving underwater vehicle and a scaled-down test model capable of conducting actual experiments, providing a scenario framework for the dynamic coupling of three loads. The preset depth range can be 3000m–6000m, determined using the formula... Calculate the hydrostatic pressure corresponding to several depths. ,in The density of seawater, , It is the acceleration due to gravity. ,exist hour, ; hour, Next, an external experimental chamber (high-pressure water chamber) providing a hydrostatic pressure environment of 0–70 MPa was used to conduct underwater explosion tests on the scaled-down model under different hydrostatic pressure conditions. Each test was repeated multiple times to ensure data reliability. Multi-channel piezoelectric pressure sensors were deployed in the experimental chamber to obtain the pressure-time history curves of the simulated structure surface; strain gauges were placed on the structure surface to obtain the strain-time history curves of the simulated structure; and a high-speed camera was used to capture the bubble expansion-collapse process to obtain the simulated bubble trajectory, providing raw data support for subsequent quantification of the dynamic characteristics and interaction mechanisms of the three loads. Then, based on the pressure-time history curves of the simulated structure surface and the hydrostatic pressure corresponding to several diving depths, the modulation of the shock wave propagation characteristics by hydrostatic pressure was realized, and an initial hydrostatic pressure term was constructed, providing the basic load components for the construction of the joint load spectrum.

[0031] Subsequently, by constructing an initial shock wave pressure time history term, the modulation effect of hydrostatic pressure on the shock wave can be quantified, fully reconstructing the time history and pressure amplitude changes of the shock wave propagating from the explosion source to the surface of the underwater vehicle structure. The resulting initial shock wave pressure time history term provides dynamic load components that conform to actual working conditions for the joint load spectrum. Next, by fusing simulated bubble motion trajectories, simulated structural surface pressure time history curves, simulated structural surface pressure time history curves, hydrostatic pressure corresponding to several diving depths, explosion source distance corresponding to the peak shock wave pressure, and charge equivalent corresponding to the peak shock wave pressure, dynamic coupling between bubble pulsation, hydrostatic pressure, and the explosion parameters of the underwater explosion shock wave is achieved. The resulting initial bubble pulsation pressure time history term provides dynamic load components for the joint load spectrum. Finally, the initial hydrostatic pressure term, the initial shock wave pressure time history term, and the initial bubble pulsation pressure time history term are superimposed to construct a joint load spectrum, which is then input into the finite element analysis software ABAQUS. A pre-written Python script in ABAQUS is used to load the joint load spectrum into the prototype simulation model, ensuring that the temporal correlation and spatial distribution characteristics of the loads are consistent with the actual situation. This results in a joint load simulation model capable of dynamically coupling high hydrostatic pressure, underwater explosion shock waves, and bubble pulsation. Simulation is performed using this joint load simulation model, i.e., finite element calculations are performed on the joint load simulation model to simulate... The dynamic response process of an underwater vehicle structure under combined loads simulates the stress process of an underwater vehicle structure under actual complex combined loads. The obtained prototype strain data can be used to calculate with scaled strain data to verify the effectiveness of the equivalent conversion of the combined load spectrum and the reliability of the simulation model, i.e., to determine whether the simulation reliability conditions are met. If the simulation reliability conditions are met, it indicates that the constructed combined load simulation model can accurately characterize the load process and structural response law of a deep-diving underwater vehicle in an actual deep-water explosion environment, thus realizing the simulation of the deep-diving underwater vehicle's resistance to deep-water explosions. The combined load spectrum is provided in tabular form, including pressure values ​​at different time points and locations. In the finite element analysis software, corresponding boundary conditions and calculation parameters are set according to the prototype underwater vehicle: in terms of boundary conditions, considering the free floating state of the underwater vehicle underwater, inertial release constraints are applied to the model; in terms of calculation parameters, an explicit dynamic analysis algorithm is adopted, with a time step set to 1e-6 seconds to accurately capture the transient response of the explosion impact. The total time is calculated based on the bubble pulsation period to cover the entire process of the shock wave action and the first bubble pulsation.

[0032] Furthermore, it also includes: If the strain data error does not meet the simulation reliability conditions, the joint load spectrum is reconstructed and loaded into the prototype simulation model to obtain the joint load simulation model. The joint load simulation model is then re-simulated to update the prototype strain data. Based on the prototype strain data and the scaled-down strain data, the strain data error is obtained until the strain data error meets the simulation reliability conditions.

[0033] In this embodiment, by reconstructing the joint load spectrum when the strain data error does not meet the simulation reliability conditions, the parameter deviations of high hydrostatic pressure, underwater explosion shock wave, and bubble pulsation in the dynamic coupling process can be corrected. This ensures that the obtained joint load simulation model can closely match the load action process and structural response law of the deep-diving underwater vehicle in the actual deep-water explosion environment, providing accurate load input for updating the prototype strain data. Then, by updating the prototype strain data and scaled-down strain data to obtain the strain data error, until the strain data error meets the simulation reliability conditions, it can be ensured that the joint load simulation model at this time can reflect the interaction of high hydrostatic pressure, underwater explosion shock wave, and bubble pulsation, as well as the actual stress response of the underwater vehicle structure. This achieves high-precision and high-reliability simulation of the deep-diving underwater vehicle's resistance to deep-water explosions, avoiding simulation result distortion due to insufficient fitting accuracy.

[0034] Furthermore, based on the underwater vehicle's external geometric data, a preset diving depth range, and the target structural region of the underwater vehicle, the calculation of hydrostatic pressure at several diving depths and the equivalent hydrostatic pressure distribution of the target structural region of the underwater vehicle, and the establishment of a prototype simulation model and a scaled-down test model, includes: Based on a preset depth range, obtain the hydrostatic pressure corresponding to several depths; Based on the target structure region of the underwater vehicle and the hydrostatic pressure corresponding to several diving depths, the equivalent hydrostatic pressure distribution of the target structure region of the underwater vehicle is calculated. Based on the underwater vehicle's external geometric data, hydrostatic pressure corresponding to several diving depths, preset hydrostatic pressure similarity ratio, preset geometric similarity ratio, structural material parameters, preset material similarity ratio, preset explosive equivalent, preset detonation center distance range, preset explosive type, and preset explosive equivalent similarity ratio, a prototype simulation model and a scaled-down experimental model are established.

[0035] In this embodiment, by obtaining the hydrostatic pressure corresponding to several diving depths within a preset diving depth range, the hydrostatic pressure corresponding to different depths of the underwater vehicle in a diving environment can be clearly identified, providing basic data that fits the actual working conditions for subsequent calculation of equivalent hydrostatic pressure distribution and establishment of a prototype simulation model. Next, by calculating the equivalent hydrostatic pressure distribution of the underwater vehicle's target structural region using the hydrostatic pressure corresponding to several diving depths, the distribution of hydrostatic pressure on the shell surface of the underwater vehicle's target structural region can be calculated or solved using finite element methods. The equivalent hydrostatic pressure distribution at different curvatures and positions of the underwater vehicle's target structural region can be calculated, and the obtained equivalent hydrostatic pressure distribution can accurately characterize the spatial distribution differences of hydrostatic pressure at different parts of the underwater vehicle's target structure, thereby providing boundary basis for the precise spatial application of combined loads. Then, by integrating hydrostatic pressure, preset hydrostatic pressure similarity ratio, preset geometric similarity ratio, structural material parameters, preset material similarity ratio, preset explosive equivalent, preset detonation center distance range, preset explosive type, and preset explosive equivalent similarity ratio corresponding to several diving depths, a prototype simulation model can be constructed based on the structural characteristics of the deep-diving underwater vehicle and the physical process of deep-water explosion impact. A scaled-down test model that meets the scaling equivalence criterion can also be constructed using the finite element analysis software ABAQUS. Based on the external geometric data of the underwater vehicle, three-dimensional models of the pressure hull, bulkheads, and internal support structures can be performed. The combined load under the high-pressure environment of deep diving can be converted into load conditions that can be realized in the laboratory. This enables accurate replication of the actual deep-water explosion environment of the deep-diving underwater vehicle, providing a reliable platform for dynamic coupling tests of three loads: high hydrostatic pressure, underwater explosion shock wave, and bubble pulsation. The preset geometric similarity ratio is the ratio of the feature dimensions of the prototype simulation model to the feature dimensions of the underwater vehicle's external geometric data, and can be taken as 1 / 10. The prototype simulation model preferably uses the same material as the underwater vehicle; therefore, the preset material similarity ratio can be taken as 1. The preset material similarity ratio includes density similarity ratio, elastic modulus similarity ratio, and material strength similarity ratio. The prototype simulation model uses hexahedral elements for mesh generation. In critical structural areas, such as the corners where the bulkhead connects to the hull, a denser mesh with a mesh size of 5mm is used; in other areas, the mesh size is 10-20mm to improve computational efficiency while ensuring computational accuracy. This allows for accurate replication of the actual deep-water explosion environment of the deep-diving underwater vehicle, providing a reliable platform for the dynamic coupling simulation of three loads: high hydrostatic pressure, underwater explosion shock waves, and bubble pulsation. The preset explosive type can be TNT, with a preset explosive equivalent of 1 kg–50 kg, and a preset detonation center distance range of 1m–50m.

[0036] Furthermore, based on the simulated surface pressure time history curve and the hydrostatic pressure corresponding to several depths, the peak shock wave pressure, the charge equivalent corresponding to the peak shock wave pressure, the explosion source distance corresponding to the peak shock wave pressure, the shock wave distance attenuation parameter, the charge medium coupling coefficient, and the correlation parameter of the peak explosion shock wave pressure are obtained. An initial hydrostatic pressure term is constructed based on the hydrostatic pressure corresponding to several depths, including: Based on the simulated surface pressure time history curve and the preset detonation center distance range, the peak pressure of the shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, and the detonation source distance corresponding to the peak pressure of the shock wave are extracted. The peak pressure of the shock wave and the corresponding explosion source distance are fitted to obtain the fitting coefficient of the peak pressure of the first hydrostatic shock wave and the fitting coefficient of the peak pressure of the second hydrostatic shock wave. Based on the fitting coefficient of the peak pressure of the first hydrostatic shock wave, the fitting coefficient of the peak pressure of the second hydrostatic shock wave, and the hydrostatic pressure corresponding to several depths, the shock wave distance attenuation parameter is obtained. The coupling coefficient of the charge medium is obtained by fitting the preset explosive type and preset medium environment; By fitting the peak pressure of the shock wave and the corresponding charge equivalent, the correlation parameters of the peak pressure of the explosion shock wave are obtained. The initial hydrostatic pressure term is constructed based on the hydrostatic pressure corresponding to several depths.

[0037] In this embodiment, by simulating the pressure-time history curve of the structural surface and a preset detonation center distance range, the peak shock wave pressure, the corresponding charge equivalent W, and the detonation source distance R are extracted, clarifying the core characteristic parameters of the underwater explosion shock wave load and providing basic data for subsequent quantification of the hydrostatic pressure modulation mechanism. Next, the peak shock wave pressure and the corresponding detonation source distance are fitted to obtain the fitting coefficients for the first and second hydrostatic pressure peak shock wave pressures, establishing a quantitative correlation between the peak shock wave pressure and the detonation source distance, laying the foundation for subsequent derivation of the shock wave distance attenuation parameters. Then, the fitting coefficients for the first and second hydrostatic pressure peak shock wave pressures and the hydrostatic pressures corresponding to several depths are used to... Through the formula: To obtain the shock wave distance attenuation parameters, where, The fitting coefficient for the peak pressure of the first hydrostatic shock wave is given. The second hydrostatic pressure shock wave peak pressure fitting coefficient quantifies the modulation effect of hydrostatic pressure on the shock wave propagation attenuation characteristics, improving the multi-dimensional description of shock wave propagation laws in deep-diving environments. Subsequently, fitting is performed on preset explosive types and preset medium environments to obtain the charge-medium coupling coefficient, clarifying the interaction characteristics between the explosive type and the underwater medium, providing key parameters for constructing the initial shock wave pressure time history term. Next, by fitting the shock wave peak pressure and the corresponding charge equivalent, a quantitative relationship between the shock wave peak pressure and the charge equivalent can be established, obtaining the correlation parameters of the explosive shock wave peak pressure, ensuring an accurate description of the shock wave load under different charge equivalent explosion conditions. Finally, an initial hydrostatic pressure term is constructed using hydrostatic pressures corresponding to several depths, providing basic load components for constructing the joint load spectrum.

[0038] Furthermore, the initial shock wave pressure time history term is constructed based on the simulated structural surface pressure time history curve, the peak pressure correlation parameters of the explosion shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the blast source distance corresponding to the peak pressure of the shock wave, the coupling coefficient of the charge medium, and the shock wave distance attenuation parameters, including: Based on the peak pressure correlation parameters of the explosion shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the blast source distance corresponding to the peak pressure of the shock wave, the preset distance similarity ratio, the coupling coefficient of the charge medium, and the shock wave distance attenuation parameters, the peak pressure parameters of the hydrostatic pressure modulated shock wave are calculated. Based on the simulated surface pressure time history curve, the charge equivalent corresponding to the peak pressure of the shock wave, the explosion source distance corresponding to the peak pressure of the shock wave, and the similarity ratio of the preset explosive equivalent, the shock wave decay time constant is obtained. Based on the peak pressure parameters of the hydrostatic modulated shock wave and the shock wave decay time constant, an initial shock wave pressure time history term is constructed.

[0039] In this embodiment, by using parameters related to the peak pressure of the explosion shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the blast source distance corresponding to the peak pressure of the shock wave, the preset distance similarity ratio, the coupling coefficient of the charge medium, and the shock wave distance attenuation parameters, the dynamic influence of hydrostatic pressure on the peak pressure of the shock wave can be quantified, preventing the neglect of the modulation effect of hydrostatic pressure on the shock wave. The obtained hydrostatic pressure modulated peak pressure parameters of the shock wave can closely match the actual working conditions of deep-sea submersibles in deep-water explosions, specifically: Next, by simulating the time history curve of the pressure on the structural surface, the charge equivalent corresponding to the peak pressure of the shock wave, the distance from the detonation source corresponding to the peak pressure of the shock wave, and the similarity ratio of the preset explosive equivalent, the shock wave decay time constant is obtained. Specifically, by simulating the time history curve of the pressure on the structural surface, the actual decay time intervals of several peak pressures of the shock waves are extracted. ,according to ,in, This represents the first attenuation calibration parameter. This represents the second attenuation calibration parameter, where W represents the charge equivalent corresponding to the peak pressure of the shock wave. Used to correlate the explosion energy with the time characteristics of the shock wave, R(x) represents the distance from the explosion source corresponding to the peak pressure of the shock wave. This represents a scaled-down distance term, used to eliminate the coupling effect between the explosive yield and distance, thus allowing for a better fit. , Next, the obtained , Substitute, The shock wave decay time constant was obtained. This study accurately captured the attenuation law of the shock wave under hydrostatic pressure, providing parameter support for the subsequent accurate construction of the initial shock wave pressure time history term and the complete reconstruction of the time dimension characteristics of the shock wave. Then, by modulating the peak pressure parameter and the shock wave attenuation time constant under hydrostatic pressure, the initial shock wave pressure time history term was constructed. Specifically, the initial shock wave pressure time history term adopts an exponential decay form: ,in, The peak pressure parameter of the shock wave modulated by hydrostatic pressure. The shock wave decay time constant is used to reconstruct the pressure change process of the dynamic coupling between hydrostatic pressure and shock wave, which can provide dynamic load components that conform to the actual physical mechanism for the joint load spectrum, ensuring the accuracy of the deep-sea explosion resistance simulation of deep-sea submersible vehicles.

[0040] Furthermore, the initial bubble pulsation pressure time history term is constructed based on the simulated bubble motion trajectory, the simulated structural surface pressure time history curve, the hydrostatic pressure corresponding to several depths, the explosion source distance corresponding to the peak shock wave pressure, and the charge equivalent corresponding to the peak shock wave pressure, including: Based on the simulated bubble motion trajectory, the simulated structural surface pressure time history curve, the simulated structural surface pressure time history curve, the hydrostatic pressure corresponding to several diving depths, the explosion source distance corresponding to the peak pressure of the shock wave, and the charge equivalent corresponding to the peak pressure of the shock wave, the pulse period fitting parameters, the first pulse fitting parameters, the second pulse fitting parameters, the third pulse fitting parameters, the pulse damping time constant, and the pulse start time are calculated. Based on the first pulsating pulse fitting parameters, the second pulsating pulse fitting parameters, the third pulsating pulse fitting parameters, the pulsation period fitting parameters, the pulse damping time constant, the pulse start time, and the explosive equivalent similarity ratio, the initial bubble pulsating pressure time history term is constructed.

[0041] In this embodiment, by simulating the bubble motion trajectory, the time history curve of the simulated structural surface pressure, the hydrostatic pressure corresponding to several depths, the blast source distance corresponding to the peak shock wave pressure, and the charge equivalent corresponding to the peak shock wave pressure, the modulation effect of hydrostatic pressure on bubble pulsation can be quantified. The calculated pulsation period fitting parameters, first pulsation pulse fitting parameters, second pulsation pulse fitting parameters, third pulsation pulse fitting parameters, pulse damping time constant, and pulse start time provide parameter support for constructing the initial bubble pulsation pressure time history term. Next, using the first pulsation pulse fitting parameters, second pulsation pulse fitting parameters, third pulsation pulse fitting parameters, pulsation period fitting parameters, pulse damping time constant, pulse start time, and explosive equivalent similarity ratio, the initial bubble pulsation pressure time history term is constructed. Specifically, the initial bubble pulsation pressure time history term is represented by a superposition of multiple pulse damped sine waves. Where N is the number of bubble pulsation pulses considered; Let be the amplitude of the Kth pulse; This represents the start time (or arrival time) of the kth pulse. Let be the damping time constant of the k-th pulse; H is the bubble pulsation period; H(⋅) is the Heaviside step function, used to ensure that when t < 0. When the kth pulse is inactive, the dynamic process of the bubble under hydrostatic pressure modulation can be completely restored. The constructed initial bubble pulsation pressure time history term can realize the dynamic coupling between bubble pulsation, hydrostatic pressure and the explosion parameters of underwater explosion shock wave, and provide dynamic load components for the joint load spectrum, ensuring the integrity and accuracy of the deep-sea explosion simulation of the deep-sea vehicle.

[0042] Furthermore, the calculation of the pulse period fitting parameters, first pulse fitting parameters, second pulse fitting parameters, third pulse fitting parameters, pulse damping time constant, and pulse start time based on the simulated bubble motion trajectory, simulated structural surface pressure time history curve, simulated structural surface pressure time history curve, hydrostatic pressure corresponding to several depths, explosion source distance corresponding to shock wave peak pressure, and charge equivalent corresponding to shock wave peak pressure, includes: Based on the simulated bubble motion trajectory, the bubble pulsation period is extracted; Based on the bubble pulsation period, the hydrostatic pressure corresponding to several diving depths, the charge equivalent corresponding to the peak pressure of the shock wave, and the similarity ratio of the explosive equivalent, the pulsation period fitting parameters are calculated. Based on the time history curve of the simulated structure surface pressure, the peak value of bubble pulsation pressure is extracted; Based on the hydrostatic pressure corresponding to the aforementioned depths, the preset reference pressure, the explosion source distance corresponding to the peak shock wave pressure, the charge equivalent corresponding to the peak shock wave pressure, the explosive equivalent similarity ratio, and the peak pressure of bubble pulsation, the first pulsation pulse fitting parameters, the second pulsation pulse fitting parameters, and the third pulsation pulse fitting parameters are obtained. Based on the simulated surface pressure time history curve, the pulse damping time constant and pulse start time are extracted.

[0043] In this embodiment, by simulating the bubble motion trajectory to extract the bubble pulsation period, the dynamic characteristics of the bubble under hydrostatic pressure can be accurately captured, providing basic data for the subsequent calculation of pulsation period fitting parameters. Next, by using the bubble pulsation period, the hydrostatic pressure corresponding to several depths, the charge equivalent corresponding to the peak shock wave pressure, and the explosive equivalent similarity ratio, the modulation effect of hydrostatic pressure and charge equivalent on the bubble pulsation period can be quantified, ensuring that the calculated pulsation period fitting parameters conform to the equivalence criterion of the explosive equivalent similarity ratio. Specifically: ,in, This represents the fitting parameters for the pulsation period. Indicates atmospheric pressure. The bubble pulsation period is defined. Then, the peak pressure of the bubble pulsation is extracted by simulating the pressure-time history curve of the structural surface, providing key data for calculating the following pulsation pulse fitting parameters. Subsequently, using the hydrostatic pressure corresponding to several depths, the preset reference pressure, the explosion source distance corresponding to the peak shock wave pressure, the charge equivalent corresponding to the peak shock wave pressure, the explosive equivalent similarity ratio, and the peak pressure of the bubble pulsation, the first, second, and third pulsation pulse fitting parameters are obtained, specifically: ,in, This represents the fitting parameters for the first pulsating pulse. This represents the fitting parameters for the second pulsating pulse. This represents the fitting parameters for the third pulsating pulse. The preset reference pressure, typically taken as an engineering benchmark value such as 1 atm or 1 MPa, establishes a quantitative correlation between the bubble pulsation amplitude and multiple influencing factors. This ensures the variation law of bubble pulsation pressure under different operating conditions, thereby enabling an accurate description of bubble pulsation pressure under various operating conditions and providing reliable support for constructing the bubble pulsation pressure time history term in the joint load spectrum. Finally, by simulating the pressure time history curve of the structural surface, the pulse damping time constant and pulse start time are extracted, providing parameter basis for the time dimension modeling of the initial bubble pulsation pressure time history term.

[0044] Further, the initial hydrostatic pressure term, the initial shock wave pressure time history term, and the initial bubble pulsation pressure time history term are superimposed to construct a joint load spectrum, and the joint load spectrum is loaded into the prototype simulation model to obtain a joint load simulation model. The joint load simulation model is then used to simulate the joint load simulation model and obtain prototype strain data. Based on the prototype strain data and the scaled-down strain data, the strain data error is obtained. If the strain data error meets the simulation reliability conditions, the simulation of the deep-sea submersible's resistance to deep-water explosions is completed, including: Based on the preset hydrostatic pressure similarity ratio and the initial hydrostatic pressure term, the first hydrostatic pressure term is obtained; based on the preset shock wave peak pressure similarity ratio and the initial shock wave pressure time history term, the first shock wave pressure time history term is obtained; based on the preset bubble pulsation pressure similarity ratio and the initial bubble pulsation pressure time history term, the first bubble pulsation pressure time history term is obtained. The first hydrostatic pressure term, the first shock wave pressure time history term, and the first bubble pulsation pressure time history term are superimposed to construct a joint load spectrum, and the joint load spectrum is loaded into the prototype simulation model to obtain the joint load simulation model. The combined load simulation model was simulated to obtain prototype strain data; Based on prototype strain data and scaled-down strain data, the strain data error is obtained. If the strain data error meets the simulation reliability conditions, the simulation of the deep-sea submersible's resistance to deep-sea explosions is completed.

[0045] In this embodiment, a first hydrostatic pressure term is obtained by presetting a hydrostatic pressure similarity ratio and an initial hydrostatic pressure term; a first shock wave pressure time history term is obtained by presetting a shock wave peak pressure similarity ratio and an initial shock wave pressure time history term; and a first bubble pulsation pressure time history term is obtained by presetting a bubble pulsation pressure similarity ratio and an initial bubble pulsation pressure time history term. This achieves equivalent scaling of each load term, making the load parameters conform to the actual operating conditions of the prototype deep-diving underwater vehicle, laying the foundation for constructing a realistic joint load spectrum. The joint load spectrum is constructed by superimposing the first hydrostatic pressure term, the first shock wave pressure time history term, and the first bubble pulsation pressure time history term, specifically as follows: , where x is the spatial coordinate of the structural surface of the target area of ​​the underwater vehicle, and t is time; This is the first hydrostatic pressure term; For the first shock wave pressure time history term, For the first bubble pulsation pressure time history term, denoted as , where is the distance from the explosion source to location x; W is the explosive equivalent corresponding to the peak pressure of the shock wave; h is the water depth. The combined load spectrum is obtained. This spectrum dynamically couples high hydrostatic pressure, underwater explosion shock waves, and bubble pulsation. Loading this spectrum onto a prototype simulation model yields a combined load simulation model, achieving a realistic simulation of the dynamic coupling effects of high hydrostatic pressure, underwater explosion shock waves, and bubble pulsation, thus improving the consistency between the simulation model and the actual load scenario. Then, by simulating the combined load simulation model, prototype strain data is obtained, revealing the dynamic response of the deep-diving underwater vehicle structure under real combined loads. This provides data support for subsequent verification of simulation reliability and optimization of structural design. Subsequently, the obtained prototype strain data can be compared with scaled strain data for calculations. Specifically, the least squares method is used to calibrate the fitting coefficients for three types of hydrostatic stresses using both the prototype strain data and the scaled strain data. ,in, This represents the fitting coefficient for the first hydrostatic stress. This represents the fitting coefficient for the second hydrostatic stress. This represents the fitting coefficient for the third hydrostatic stress. The strain data is represented by the above formula. The obtained prototype strain data and scaled strain data are substituted into the formula to establish the correlation between hydrostatic pressure and the prototype and scaled strain data respectively. The strain data error is obtained through the curves fitted by both. The validity of the equivalent transformation of the combined load spectrum and the reliability of the simulation model are verified, i.e., whether the strain data error meets the simulation reliability conditions. If the simulation reliability conditions are met, it indicates that the constructed combined load simulation model can accurately characterize the load process and structural response law of the deep-diving underwater vehicle in the actual deep-water explosion environment. The dynamic response parameters such as stress, strain, and displacement of the underwater vehicle structure can be obtained by simulating the combined load simulation model, completing the simulation of the deep-diving underwater vehicle's resistance to deep-water explosions. This ensures that the underwater vehicle structure can meet the impact resistance requirements in actual applications, effectively avoiding safety hazards caused by inaccurate simulations and preventing it from being unable to effectively cope with existing risks in real explosion impact scenarios. Thus, the simulation of the deep-diving underwater vehicle's resistance to deep-water explosions is realized. If the form obtained by fitting with a quadratic polynomial is insufficient to characterize the pattern, then an existing higher-order polynomial or exponential form can be selected for refitting based on the data characteristics.

[0046] Please see Figure 2 This embodiment provides a simulation system for the resistance of a deep-sea submersible to deep-water explosion impacts. It is applied to the simulation method described above for the resistance of a deep-sea submersible to deep-water explosion impacts. The system includes a data acquisition module, a prototype simulation model construction module, a data acquisition module, a hydrostatic pressure term construction module, a shock wave pressure time history term construction module, a bubble pulsation pressure time history term construction module, and a simulation verification module. Specifically: The data acquisition module is used to acquire the geometric data of the underwater vehicle's shape and the target structural region of the underwater vehicle, and to acquire structural material parameters based on the target structural region of the underwater vehicle. The prototype simulation model construction module is used to calculate the hydrostatic pressure corresponding to several diving depths and the equivalent hydrostatic pressure distribution of the target structure area of ​​the underwater vehicle based on the underwater vehicle's external geometric data, preset diving depth range and underwater vehicle target structure area, and to establish a prototype simulation model and a scaled-down test model. The data acquisition module is used to control the external experimental chamber to conduct tests on the scaled-down test model in order to obtain the time history curve of the simulated structure surface pressure, the time history curve of the simulated structure strain, the simulated bubble motion trajectory, and the scaled-down strain data. The hydrostatic pressure term construction module is used to obtain the peak pressure of the shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the explosion source distance corresponding to the peak pressure of the shock wave, the shock wave distance attenuation parameter, the charge medium coupling coefficient and the correlation parameter of the peak pressure of the explosion shock wave based on the time history curve of the pressure on the simulated structure surface and the hydrostatic pressure corresponding to several depths, and to construct the initial hydrostatic pressure term based on the hydrostatic pressure corresponding to several depths. The shock wave pressure time history term construction module is used to construct an initial shock wave pressure time history term based on the simulated structure surface pressure time history curve, the peak pressure correlation parameters of the explosion shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the blast source distance corresponding to the peak pressure of the shock wave, the coupling coefficient of the charge medium, and the shock wave distance attenuation parameters. The bubble pulsation pressure time history term construction module is used to construct an initial bubble pulsation pressure time history term based on the simulated bubble motion trajectory, the simulated structural surface pressure time history curve, the simulated structural surface pressure time history curve, the hydrostatic pressure corresponding to several depths, the explosion source distance corresponding to the peak pressure of the shock wave, and the charge equivalent corresponding to the peak pressure of the shock wave. The simulation verification module is used to superimpose the initial hydrostatic pressure term, the initial shock wave pressure time history term, and the initial bubble pulsation pressure time history term to construct a joint load spectrum, and load the joint load spectrum into the prototype simulation model to obtain a joint load simulation model, so as to simulate the joint load simulation model and obtain prototype strain data; based on the prototype strain data and the scaled strain data, the strain data error is obtained. If the strain data error meets the simulation reliability condition, the simulation of the deep-sea submersible's resistance to deep-water explosion is completed.

[0047] This embodiment provides a simulation system for simulating the impact resistance of a deep-sea submersible to deep-water explosions. In practical applications, only a data acquisition module is needed. First, the external geometric data and target structural regions of the deep-sea submersible to be simulated are acquired. Specifically, the target structural regions refer to the connection points between the pressure hull and bulkheads, reinforced sections of hull openings, or locally reinforced areas. Then, structural material parameters are obtained based on the target structural regions. For example, if the structural material is high-strength alloy steel, the structural material parameters are set according to the parameters for high-strength alloy steel, such as density. elastic modulus The Poisson's ratio is 0.3, and the yield strength is 800 MPa. Then, using a prototype simulation model construction module, the hydrostatic pressure and equivalent hydrostatic pressure distribution of the underwater vehicle's target structural region at several depths were calculated within a preset depth range. A prototype simulation model and a scaled-down test model were established, constructing a simulation carrier that closely matches the actual deep-water environment of a deep-diving underwater vehicle and a scaled-down test model capable of conducting actual experiments. This provides a scenario framework for the dynamic coupling of the three loads. The preset depth range can be 3000m–6000m, determined using the formula... Calculate the hydrostatic pressure corresponding to several depths. ,in The density of seawater, , It is the acceleration due to gravity. ,exist hour, ; hour, Next, a data acquisition module was used to control an external experimental chamber (high-pressure water chamber) providing a hydrostatic pressure environment of 0–70 MPa to conduct underwater explosion tests on the scaled-down model under different hydrostatic pressure conditions. Each test was repeated multiple times to ensure data reliability. Multi-channel piezoelectric pressure sensors were deployed in the experimental chamber to obtain the pressure time history curves of the simulated structure surface; strain gauges were placed on the structure surface to obtain the strain time history curves of the simulated structure; and a high-speed camera was used to capture the bubble expansion-collapse process to obtain the simulated bubble trajectory, providing raw data support for subsequent quantification of the dynamic characteristics and interaction mechanisms of the three loads. Then, a hydrostatic pressure term construction module was used to modulate the shock wave propagation characteristics by hydrostatic pressure based on the pressure time history curves of the simulated structure surface and the hydrostatic pressure corresponding to several depths. At the same time, an initial hydrostatic pressure term was constructed, providing the basic load components for the construction of the joint load spectrum.

[0048] Subsequently, a shock wave pressure time history term construction module was employed. By constructing an initial shock wave pressure time history term, the modulation effect of hydrostatic pressure on the shock wave could be quantified, fully reconstructing the time history and pressure amplitude changes of the shock wave propagating from the explosion source to the surface of the underwater vehicle structure. The resulting initial shock wave pressure time history term provided dynamic load components consistent with actual working conditions for the joint load spectrum. Next, a bubble pulsation pressure time history term construction module was employed. By fusing simulated bubble motion trajectories, simulated structural surface pressure time history curves, simulated structural surface pressure time history curves, hydrostatic pressure corresponding to several diving depths, explosion source distance corresponding to the peak shock wave pressure, and charge equivalent corresponding to the peak shock wave pressure, dynamic coupling between bubble pulsation, hydrostatic pressure, and the explosion parameters of the underwater explosion shock wave was achieved. The resulting initial bubble pulsation pressure time history term provided dynamic load components for the joint load spectrum. Finally, a simulation verification module was used to superimpose the initial hydrostatic pressure term, the initial shock wave pressure time history term, and the initial bubble pulsation pressure time history term to construct a joint load spectrum, which was then input into the finite element analysis software ABAQUS. A pre-written Python script in ABAQUS was used to load the joint load spectrum into the prototype simulation model, ensuring that the temporal correlation and spatial distribution characteristics of the loads were consistent with the actual situation. This resulted in a joint load simulation model capable of dynamically coupling high hydrostatic pressure, underwater explosion shock waves, and bubble pulsation. Simulations were then performed using this joint load simulation model, i.e., finite element analysis was conducted on the joint load simulation model. The dynamic response of an underwater vehicle structure under combined loads was simulated, enabling the simulation of the stress process of the underwater vehicle structure under actual complex combined loads. The obtained prototype strain data can be compared with scaled strain data to verify the effectiveness of the equivalent conversion of the combined load spectrum and the reliability of the simulation model, i.e., to determine whether the simulation reliability conditions are met. If the simulation reliability conditions are met, it indicates that the constructed combined load simulation model can accurately characterize the load process and structural response law of a deep-diving underwater vehicle in an actual deep-water explosion environment, thus realizing the simulation of the deep-diving underwater vehicle's resistance to deep-water explosions. The combined load spectrum is provided in tabular form, including pressure values ​​at different time points and locations. In the finite element analysis software, corresponding boundary conditions and calculation parameters are set according to the prototype underwater vehicle: in terms of boundary conditions, considering the free floating state of the underwater vehicle underwater, inertial release constraints are applied to the model; in terms of calculation parameters, an explicit dynamic analysis algorithm is adopted, with a time step set to 1e-6 seconds to accurately capture the transient response of the explosion impact. The total time is calculated based on the bubble pulsation period to cover the entire process of the shock wave action and the first bubble pulsation.

[0049] Furthermore, the simulation verification module also includes: If the strain data error does not meet the simulation reliability conditions, the joint load spectrum is reconstructed and loaded into the prototype simulation model to obtain the joint load simulation model. The joint load simulation model is then re-simulated to update the prototype strain data. Based on the prototype strain data and the scaled-down strain data, the strain data error is obtained until the strain data error meets the simulation reliability conditions.

[0050] In this embodiment, by reconstructing the joint load spectrum when the strain data error does not meet the simulation reliability conditions, the parameter deviations of high hydrostatic pressure, underwater explosion shock wave, and bubble pulsation in the dynamic coupling process can be corrected. This ensures that the obtained joint load simulation model can closely match the load action process and structural response law of the deep-diving underwater vehicle in the actual deep-water explosion environment, providing accurate load input for updating the prototype strain data. Then, by updating the prototype strain data and scaled-down strain data to obtain the strain data error, until the strain data error meets the simulation reliability conditions, it can be ensured that the joint load simulation model at this time can reflect the interaction of high hydrostatic pressure, underwater explosion shock wave, and bubble pulsation, as well as the actual stress response of the underwater vehicle structure. This achieves high-precision and high-reliability simulation of the deep-diving underwater vehicle's resistance to deep-water explosions, avoiding simulation result distortion due to insufficient fitting accuracy.

[0051] To verify that the combined load simulation model obtained by the simulation method for resisting deep-water explosion impact of a deep-diving underwater vehicle used in this embodiment can accurately reflect the load application process and structural response law of the deep-diving underwater vehicle in the actual deep-water explosion environment, a step-by-step application method of hydrostatic preload and impact load was adopted for the traditional simplified model. First, a hydrostatic preload of 61.5 MPa was applied, followed by a shock wave load that does not consider the influence of hydrostatic pressure. Comparing the prototype strain data obtained by the combined load simulation model with the prototype strain data of the traditional simplified model, it was found that the maximum stress in the prototype strain data of the combined load simulation model provided in this embodiment is 15% higher than that of the traditional simplified model, and the stress distribution is more concentrated in the weak parts of the structure, which is closer to the actual situation. Secondly, since the influence of hydrostatic pressure on shock wave propagation is not considered, the shock wave velocity calculated by the traditional simplified model will be 10% lower than the actual measured value, resulting in a deviation in the prediction of prototype strain data. However, the error between the shock wave velocity calculated by the combined load simulation model of this embodiment and the actual measured value is within 2%, and the prediction of prototype strain data is more accurate. This fully demonstrates that this embodiment provides more accurate predictions of prototype strain data compared to existing technologies, offering a more reliable basis for underwater vehicle structural design. Furthermore, the simulation method for deep-diving underwater vehicles' resistance to deep-water explosion impacts, utilizing existing laboratory equipment, reduces costs by 80% and shortens the testing cycle by more than half. This provides strong support for the research and optimization design of underwater vehicle structures' impact resistance performance, demonstrating significant practicality. Finally, when underwater vehicle structures designed using existing technologies underwent actual ship testing, their impact resistance performance was found to be 15% lower than expected, requiring substantial rework and improvements. However, with the technical solution of this embodiment, the impact resistance performance of the designed underwater vehicle structure in actual ship testing showed an error of less than 5% compared to the simulation prediction results, eliminating the need for large-scale rework. This embodiment enhances the design confidence, contributing to the design of deep-diving underwater vehicle structures that better meet practical needs, thereby improving the safety and reliability of underwater vehicles.

[0052] To verify the joint load simulation model obtained by the simulation method for simulating the impact resistance of a deep-sea submersible vehicle to deep-water explosions used in this embodiment, an embodiment is provided: an submersible vehicle is provided, with a pressure hull diameter of 10 meters and a length of 100 meters, made of high-strength alloy steel with a density of 7850 kg / m³ and an elastic modulus of 210 GPa. Based on the laboratory space and experimental equipment capabilities, the preset geometric similarity ratio is 1:10, meaning the scaled-down prototype simulation model has a pressure hull diameter of 1 meter and a length of 10 meters.

[0053] According to the scaling similarity law, since the prototype simulation model uses the same high-strength alloy steel as the prototype, the preset material similarity ratio is set to 1. The preset hydrostatic pressure similarity ratio, preset shock wave peak pressure similarity ratio, preset bubble pulsation pressure similarity ratio, and preset geometric similarity ratio are the same. The bubble pulsation period similarity ratio is 1:3.16. Then, the test device for the scaled-down prototype simulation model is designed. This device mainly consists of a high-pressure test chamber, an explosive loading device, and a measuring device. The high-pressure test chamber has an inner diameter of 1.5 meters and a length of 15 meters, and can withstand a hydrostatic pressure of 10 MPa, meeting the simulation requirements of the scaled-down prototype simulation model for hydrostatic pressure. The explosive loading device uses a small explosive delivery device, which can accurately control the explosive equivalent and position. The explosive equivalent is calculated from the preset explosive equivalent based on the preset explosive equivalent similarity ratio. For example, the explosion of 50 kg TNT equivalent in the prototype corresponds to 50 × (1 / 10)³ = 0.05 kg TNT equivalent in the scaled-down model. The measuring device includes a multi-channel piezoelectric pressure sensor, strain gauges, high-speed cameras, etc., used to measure the pressure and strain experienced by the prototype simulation model, as well as the movement of bubbles.

[0054] In a laboratory environment, by adjusting relevant parameters, the combined loads under high pressure at great depths are converted into equivalent loads for model tests. For example, to simulate the explosive impact of a prototype underwater vehicle at a depth of 6000 meters (hydrostatic pressure 61.5 MPa), the corresponding hydrostatic pressure in the prototype simulation model is 61.5 MPa × (1 / 10) = 6.15 MPa. The pressure inside the high-pressure test chamber is adjusted to 6.15 MPa using the pressure control device. Simultaneously, based on the calculated explosive equivalent, the explosive is detonated at a predetermined distance from the detonation center in front of the prototype simulation model, generating an equivalent underwater explosive shock wave and bubble pulsation.

[0055] After setting the hydrostatic pressure and explosive, an explosion-resistant impact test is conducted on the prototype simulation model. Test data is collected, including the initial hydrostatic pressure term, the initial shock wave pressure time history term, and the initial bubble pulsation pressure time history term. These test data are then converted into scaled-down strain data according to preset hydrostatic pressure similarity ratios, preset shock wave peak pressure similarity ratios, preset bubble pulsation pressure similarity ratios, and preset geometric similarity ratios. The converted scaled-down strain data is then compared with the prototype strain data obtained through a joint load simulation model to obtain the strain data error. If the strain data error meets the simulation reliability condition (i.e., the strain data error is less than 5%), the equivalent conversion method is effective, and the simulation of the deep-sea submersible's resistance to deep-water explosions is completed. Otherwise, a joint load spectrum is reconstructed and loaded into the prototype simulation model to obtain a joint load simulation model, which is then re-simulated to obtain prototype strain data. Based on the prototype strain data and the scaled-down strain data, the strain data error is obtained until the strain data error meets the simulation reliability condition.

[0056] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A simulation method for resisting deep-water explosions in deep-sea submersibles, characterized in that, A simulation system for resisting deep-sea explosions in a deep-sea submersible includes: Acquire the geometric data of the underwater vehicle's external shape and the target structural region of the underwater vehicle, and obtain the structural material parameters based on the target structural region of the underwater vehicle; Based on the underwater vehicle's external geometric data, preset diving depth range, and target structure region of the underwater vehicle, the hydrostatic pressure corresponding to several diving depths and the equivalent hydrostatic pressure distribution of the target structure region of the underwater vehicle are calculated, and a prototype simulation model and a scaled-down test model are established. The external experimental chamber is controlled to conduct tests on the scaled-down test model to obtain the time history curves of pressure on the simulated structure surface, the time history curves of strain on the simulated structure, the trajectory of simulated bubbles, and the scaled-down strain data. Based on the simulated surface pressure time history curve and the hydrostatic pressure corresponding to several depths, the peak pressure of the shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the explosion source distance corresponding to the peak pressure of the shock wave, the shock wave distance attenuation parameter, the coupling coefficient of the charge medium and the correlation parameter of the peak pressure of the explosion shock wave are obtained, and the initial hydrostatic pressure term is constructed based on the hydrostatic pressure corresponding to several depths. Based on the simulated structural surface pressure time history curve, the peak pressure correlation parameters of the explosion shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the blast source distance corresponding to the peak pressure of the shock wave, the coupling coefficient of the charge medium, and the shock wave distance attenuation parameters, an initial shock wave pressure time history term is constructed. Based on the simulated bubble motion trajectory, the simulated structural surface pressure time history curve, the hydrostatic pressure corresponding to several depths, the explosion source distance corresponding to the peak pressure of the shock wave, and the charge equivalent corresponding to the peak pressure of the shock wave, an initial bubble pulsation pressure time history term is constructed. The initial hydrostatic pressure term, the initial shock wave pressure time history term, and the initial bubble pulsation pressure time history term are superimposed to construct a joint load spectrum. This joint load spectrum is then loaded into the prototype simulation model to obtain the joint load simulation model. The joint load simulation model is then used to simulate the joint load simulation model and obtain prototype strain data. Based on the prototype strain data and the scaled-down strain data, the strain data error is obtained. If the strain data error meets the simulation reliability conditions, the simulation of the deep-sea submersible's resistance to deep-water explosions is completed.

2. The simulation method for resisting deep-sea explosion impact of a deep-sea submersible according to claim 1, characterized in that, Also includes: If the strain data error does not meet the simulation reliability conditions, the joint load spectrum is reconstructed and loaded into the prototype simulation model to obtain the joint load simulation model. The joint load simulation model is then re-simulated to update the prototype strain data. Based on the prototype strain data and the scaled-down strain data, the strain data error is obtained until the strain data error meets the simulation reliability conditions.

3. The simulation method for resisting deep-sea explosion impact of a deep-sea submersible according to claim 1, characterized in that, Based on the underwater vehicle's external geometric data, a preset diving depth range, and the target structural region of the underwater vehicle, the process calculates the hydrostatic pressure corresponding to several diving depths and the equivalent hydrostatic pressure distribution of the target structural region of the underwater vehicle, and establishes a prototype simulation model and a scaled-down test model, including: Based on a preset depth range, obtain the hydrostatic pressure corresponding to several depths; Based on the target structure region of the underwater vehicle and the hydrostatic pressure corresponding to several diving depths, the equivalent hydrostatic pressure distribution of the target structure region of the underwater vehicle is calculated. Based on the underwater vehicle's external geometric data, hydrostatic pressure corresponding to several diving depths, preset hydrostatic pressure similarity ratio, preset geometric similarity ratio, structural material parameters, preset material similarity ratio, preset explosive equivalent, preset detonation center distance range, preset explosive type, and preset explosive equivalent similarity ratio, a prototype simulation model and a scaled-down experimental model are established.

4. The simulation method for resisting deep-sea explosion impact of a deep-sea submersible according to claim 1, characterized in that, The method, based on the simulated surface pressure time history curve and the hydrostatic pressure corresponding to several depths, obtains the peak shock wave pressure, the charge equivalent corresponding to the peak shock wave pressure, the blast source distance corresponding to the peak shock wave pressure, the shock wave distance attenuation parameter, the charge medium coupling coefficient, and the correlation parameter of the peak shock wave pressure. An initial hydrostatic pressure term is then constructed based on the hydrostatic pressure corresponding to several depths, including: Based on the simulated surface pressure time history curve and the preset detonation center distance range, the peak pressure of the shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, and the detonation source distance corresponding to the peak pressure of the shock wave are extracted. The peak pressure of the shock wave and the corresponding explosion source distance are fitted to obtain the fitting coefficient of the peak pressure of the first hydrostatic shock wave and the fitting coefficient of the peak pressure of the second hydrostatic shock wave. Based on the fitting coefficient of the peak pressure of the first hydrostatic shock wave, the fitting coefficient of the peak pressure of the second hydrostatic shock wave, and the hydrostatic pressure corresponding to several depths, the shock wave distance attenuation parameter is obtained. The coupling coefficient of the charge medium is obtained by fitting the preset explosive type and preset medium environment; By fitting the peak pressure of the shock wave and the corresponding charge equivalent, the correlation parameters of the peak pressure of the explosion shock wave are obtained. The initial hydrostatic pressure term is constructed based on the hydrostatic pressure corresponding to several depths.

5. The simulation method for resisting deep-sea explosion impact of a deep-sea submersible according to claim 1, characterized in that, The initial shock wave pressure time history term is constructed based on the simulated structural surface pressure time history curve, the peak pressure correlation parameters of the explosion shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the blast source distance corresponding to the peak pressure of the shock wave, the coupling coefficient of the charge medium, and the shock wave distance attenuation parameters, including: Based on the peak pressure correlation parameters of the explosion shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the blast source distance corresponding to the peak pressure of the shock wave, the preset distance similarity ratio, the coupling coefficient of the charge medium, and the shock wave distance attenuation parameters, the peak pressure parameters of the hydrostatic pressure modulated shock wave are calculated. Based on the simulated surface pressure time history curve, the charge equivalent corresponding to the peak pressure of the shock wave, the explosion source distance corresponding to the peak pressure of the shock wave, and the similarity ratio of the preset explosive equivalent, the shock wave decay time constant is obtained. Based on the peak pressure parameters of the hydrostatic modulated shock wave and the shock wave decay time constant, an initial shock wave pressure time history term is constructed.

6. The simulation method for resisting deep-sea explosion impact of a deep-sea submersible according to claim 1, characterized in that, The initial bubble pulsation pressure time history term is constructed based on the simulated bubble motion trajectory, the simulated structural surface pressure time history curve, the hydrostatic pressure corresponding to several depths, the explosion source distance corresponding to the peak shock wave pressure, and the charge equivalent corresponding to the peak shock wave pressure. This includes: Based on the simulated bubble motion trajectory, the simulated structural surface pressure time history curve, the simulated structural surface pressure time history curve, the hydrostatic pressure corresponding to several diving depths, the explosion source distance corresponding to the peak pressure of the shock wave, and the charge equivalent corresponding to the peak pressure of the shock wave, the pulse period fitting parameters, the first pulse fitting parameters, the second pulse fitting parameters, the third pulse fitting parameters, the pulse damping time constant, and the pulse start time are calculated. Based on the first pulsating pulse fitting parameters, the second pulsating pulse fitting parameters, the third pulsating pulse fitting parameters, the pulsation period fitting parameters, the pulse damping time constant, the pulse start time, and the explosive equivalent similarity ratio, the initial bubble pulsating pressure time history term is constructed.

7. The simulation method for resisting deep-sea explosion impact of a deep-diving underwater vehicle according to claim 6, characterized in that, The calculation of the pulse period fitting parameters, first pulse fitting parameters, second pulse fitting parameters, third pulse fitting parameters, pulse damping time constant, and pulse start time based on simulated bubble motion trajectory, simulated structural surface pressure time history curve, simulated structural surface pressure time history curve, hydrostatic pressure corresponding to several depths, blast source distance corresponding to shock wave peak pressure, and charge equivalent corresponding to shock wave peak pressure includes: Based on the simulated bubble motion trajectory, the bubble pulsation period is extracted; Based on the bubble pulsation period, the hydrostatic pressure corresponding to several diving depths, the charge equivalent corresponding to the peak pressure of the shock wave, and the similarity ratio of the explosive equivalent, the pulsation period fitting parameters are calculated. Based on the time history curve of the simulated structure surface pressure, the peak value of bubble pulsation pressure is extracted; Based on the hydrostatic pressure corresponding to the aforementioned depths, the preset reference pressure, the explosion source distance corresponding to the peak shock wave pressure, the charge equivalent corresponding to the peak shock wave pressure, the explosive equivalent similarity ratio, and the peak pressure of bubble pulsation, the first pulsation pulse fitting parameters, the second pulsation pulse fitting parameters, and the third pulsation pulse fitting parameters are obtained. Based on the simulated surface pressure time history curve, the pulse damping time constant and pulse start time are extracted.

8. The simulation method for resisting deep-sea explosion impact of a deep-diving underwater vehicle according to claim 1, characterized in that, The initial hydrostatic pressure term, the initial shock wave pressure time history term, and the initial bubble pulsation pressure time history term are superimposed to construct a joint load spectrum. This joint load spectrum is then loaded into the prototype simulation model to obtain a joint load simulation model. Simulation of the joint load simulation model is performed to obtain prototype strain data. Based on the prototype strain data and scaled-down strain data, the strain data error is obtained. If the strain data error meets the simulation reliability conditions, the simulation of the deep-sea submersible's resistance to deep-water explosions is completed, including: Based on the preset hydrostatic pressure similarity ratio and the initial hydrostatic pressure term, the first hydrostatic pressure term is obtained; based on the preset shock wave peak pressure similarity ratio and the initial shock wave pressure time history term, the first shock wave pressure time history term is obtained; based on the preset bubble pulsation pressure similarity ratio and the initial bubble pulsation pressure time history term, the first bubble pulsation pressure time history term is obtained. The first hydrostatic pressure term, the first shock wave pressure time history term, and the first bubble pulsation pressure time history term are superimposed to construct a joint load spectrum, and the joint load spectrum is loaded into the prototype simulation model to obtain the joint load simulation model. The combined load simulation model was simulated to obtain prototype strain data; Based on prototype strain data and scaled-down strain data, the strain data error is obtained. If the strain data error meets the simulation reliability conditions, the simulation of the deep-sea submersible's resistance to deep-sea explosions is completed.

9. A simulation system for resisting deep-sea explosion impact of a deep-sea submersible, characterized in that, A simulation method for resisting deep-water explosion impact of a deep-sea submersible vehicle as described in any one of claims 1 to 8 includes a data acquisition module, a prototype simulation model construction module, a data acquisition module, a hydrostatic pressure term construction module, a shock wave pressure time history term construction module, a bubble pulsation pressure time history term construction module, and a simulation verification module, specifically: The data acquisition module is used to acquire the geometric data of the underwater vehicle's shape and the target structural region of the underwater vehicle, and to acquire structural material parameters based on the target structural region of the underwater vehicle. The prototype simulation model construction module is used to calculate the hydrostatic pressure corresponding to several diving depths and the equivalent hydrostatic pressure distribution of the target structure area of ​​the underwater vehicle based on the underwater vehicle's external geometric data, preset diving depth range and underwater vehicle target structure area, and to establish a prototype simulation model and a scaled-down test model. The data acquisition module is used to control the external experimental chamber to conduct tests on the scaled-down test model in order to obtain the time history curve of the simulated structure surface pressure, the time history curve of the simulated structure strain, the simulated bubble motion trajectory, and the scaled-down strain data. The hydrostatic pressure term construction module is used to obtain the peak pressure of the shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the explosion source distance corresponding to the peak pressure of the shock wave, the shock wave distance attenuation parameter, the charge medium coupling coefficient and the correlation parameter of the peak pressure of the explosion shock wave based on the time history curve of the pressure on the simulated structure surface and the hydrostatic pressure corresponding to several depths, and to construct the initial hydrostatic pressure term based on the hydrostatic pressure corresponding to several depths. The shock wave pressure time history term construction module is used to construct an initial shock wave pressure time history term based on the simulated structure surface pressure time history curve, the peak pressure correlation parameters of the explosion shock wave, the charge equivalent corresponding to the peak pressure of the shock wave, the blast source distance corresponding to the peak pressure of the shock wave, the coupling coefficient of the charge medium, and the shock wave distance attenuation parameters. The bubble pulsation pressure time history term construction module is used to construct an initial bubble pulsation pressure time history term based on the simulated bubble motion trajectory, the simulated structural surface pressure time history curve, the simulated structural surface pressure time history curve, the hydrostatic pressure corresponding to several depths, the explosion source distance corresponding to the peak pressure of the shock wave, and the charge equivalent corresponding to the peak pressure of the shock wave. The simulation verification module is used to superimpose the initial hydrostatic pressure term, the initial shock wave pressure time history term, and the initial bubble pulsation pressure time history term to construct a joint load spectrum, and load the joint load spectrum into the prototype simulation model to obtain a joint load simulation model, so as to simulate the joint load simulation model and obtain prototype strain data; based on the prototype strain data and the scaled strain data, the strain data error is obtained. If the strain data error meets the simulation reliability condition, the simulation of the deep-sea submersible's resistance to deep-water explosion is completed.

10. A simulation system for resisting deep-sea explosion impact of a deep-sea submersible according to claim 9, characterized in that, The simulation verification module also includes: If the strain data error does not meet the simulation reliability conditions, the joint load spectrum is reconstructed and loaded into the prototype simulation model to obtain the joint load simulation model. The joint load simulation model is then re-simulated to update the prototype strain data. Based on the prototype strain data and the scaled-down strain data, the strain data error is obtained until the strain data error meets the simulation reliability conditions.

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