Numerical simulation method, device, equipment and medium for explosion-affected convective clouds

Abstract

The present application relates to a numerical simulation method, device, equipment and medium for the impact of explosion on convective clouds. The method comprises: simulating the convective clouds before the explosion in the WRF_LES mode based on the downloaded sounding data; in the explosion mode, establishing a partial explosion field with the explosive as the center and simulating and calculating the explosion shock wave; using visualization software to view the operation results of the explosion mode, and determining the coupling time between the WRF_LES mode and the explosion mode according to the preset distance and pressure constraints, and at the moment of the coupling time, averaging and splicing the partial explosion field in turn to obtain a complete explosion field; coupling the complete explosion field into the WRF_LES mode, and re-running the WRF_LES mode to simulate the convective clouds after the explosion. The present method can accurately simulate and describe the impact of the explosion on the convective clouds.

Description

Technical Field

[0001] The present application relates to the field of numerical simulation technology, and in particular to a method, device, equipment and medium for numerically simulating explosion-affected convective clouds. Background Art

[0002] Convective clouds are an important component of the Earth's atmospheric system. They not only cause extreme weather events such as heavy precipitation and thunderstorms on a local scale, affecting human life and activities, but also affect the atmospheric thermal structure through radiation effects on a global scale, regulating the Earth's energy balance and water cycle system, and thus affecting climate sensitivity. The microphysical processes and macrodynamic characteristics of convective clouds have a direct impact on the effectiveness of artificial weather modification. By spreading catalysts into clouds, the precipitation potential of clouds can be adjusted, thereby increasing or decreasing precipitation to a certain extent.

[0003] In weather modification operations, anti-aircraft guns or rockets carrying catalysts are often launched into convective clouds to cause explosions and subsequent catalysis. In addition to the release of catalysts, the impact of the spreading system on the cloud during catalysis in the cloud is also reflected in the impact of the shells exploding in the cloud. Explosion is a process of rapid energy release. In a very short period of time, the high-temperature and high-pressure gas generated by it rapidly expands and compresses to form a shock wave, which spreads to the surroundings and produces significant thermal and dynamic effects on the surrounding environment. The shock wave can generate an additional equivalent pressure field within 100 meters around the explosion point. This pressure field is the pressure gradient force within the range, which is equivalent to the negative buoyancy with a disturbance temperature of -2°C. Therefore, when the explosion position is configured with the airflow field, this negative buoyancy will brake the 3-4m / s rising airflow within 100 meters to 0m / s, inhibiting the development of convection. Almost simultaneously with the shock wave, there are also sound waves. After the sound waves generated by the explosion enter the moving boundary layer of the precipitation particles, they can promote the momentum exchange between particles, accelerate the bottom airflow of the particle moving boundary layer, change the flow model, reduce resistance, and accelerate the falling of particles. The impact of explosions on convective clouds is significant, and it is necessary to develop cloud models that can simulate explosion effects.

[0004] At present, there are only a few numerical simulation methods used at home and abroad to describe the impact of explosions on convective clouds. However, the existing numerical research on the impact of explosions on convective clouds is based on formula derivation and two-dimensional model simulation, and has not yet been simulated in a three-dimensional model; on the other hand, only a mathematical model of the propagation of explosion shock waves in the atmosphere has been established, without considering the influence of the additional motion model of particles in the cloud under the influence of thermal effects. Summary of the invention

[0005] Based on this, it is necessary to provide a numerical simulation method, device, equipment and medium for the impact of explosion on convective clouds in order to address the above technical problems and realize three-dimensional numerical simulation of the impact of explosion on convective clouds.

[0006] A numerical simulation method for explosion-affected convective clouds, the method comprising:

[0007] Download and obtain the sounding data within the target three-dimensional space, and use the sounding data as the input parameters of the numerical simulation to simulate the convective clouds before the explosion in the WRF_LES mode;

[0008] In the WRF_LES mode, the parameter field of the simulated convective cloud at the set explosion time and explosion position is obtained, and the parameter field is used as the initial explosion field. In the explosion mode, a partial explosion field is established with the explosive as the center and the explosion shock wave is simulated and calculated to obtain the physical quantity information of the partial explosion field.

[0009] Use visualization software to view the operation results of the explosion mode, and determine the coupling time between the WRF_LES mode and the explosion mode according to the preset distance and pressure constraints. At the coupling time, average and splice the partial explosion fields in turn to obtain a complete explosion field.

[0010] The complete explosion field is coupled into the WRF_LES model, and the convective cloud after the explosion is simulated by re-running the WRF_LES model to obtain the physical quantity information of the convective cloud after the explosion.

[0011] In one embodiment, downloading and acquiring sounding data within a target three-dimensional space, and using the sounding data as input parameters for numerical simulation, includes:

[0012] Download and obtain the sounding data within the target three-dimensional space, and select five physical quantities, including height, potential temperature, water vapor mixing ratio, longitude wind and latitude wind, from the sounding data as input parameters for numerical simulation.

[0013] In one embodiment, simulating convective clouds before an explosion in the WRF_LES mode includes:

[0014] In the WRF_LES mode, numerical simulation of convective clouds before the explosion is performed according to the set grid range, simulation time, horizontal spatial resolution, number of horizontal grid points, number of vertical layers, model top height, vertical resolution and time step. During the simulation, the microphysics scheme selects the Thompson scheme and closes the radiation transfer scheme.

[0015] Furthermore, the source and sink terms of the mass concentration and number concentration of water species in the simulated convective clouds are calculated and output in the WRF_LES mode, expressed as

[0016] ;

[0017] ;

[0018] in, Represents water in convective clouds The mass concentration and number concentration of water substances Includes water vapor, cloud droplets, raindrops, ice crystals, snow crystals, graupel and hail; Represents the mass concentration and number concentration of water substances over time changes; represents the advection term, represents the three-dimensional wind field; represents the diffusion term; Represents microphysical terms. The specific microphysical processes of microphysical terms are output in the microphysical scheme, including cloud water condensation or evaporation, cloud-rain automatic conversion, cloud-rain collision, raindrop evaporation, and raindrop falling process; Represents a 3D gradient operator.

[0019] In one embodiment, a parameter field of a convective cloud simulated at a set explosion time and explosion position is obtained in the WRF_LES mode, and the parameter field is used as the initial explosion field. In the explosion mode, a partial explosion field is established with the explosive as the center and the explosion shock wave is simulated and calculated to obtain physical quantity information of the partial explosion field, including:

[0020] In the WRF_LES mode, the parameter field of the simulated convective cloud at the set explosion time and explosion location is obtained. The parameter field includes the air pressure, temperature, density and three-dimensional wind field of the convective cloud, and the parameter field is used as the initial explosion field.

[0021] In the explosion mode BlastFoam, a 1 / 8 explosion field is established with the explosive as the center and the explosion shock wave is simulated and calculated to obtain the physical quantity information of the 1 / 8 explosion field, including air pressure, temperature and three-dimensional wind field; when establishing the 1 / 8 explosion field with the explosive as the center, symmetry constraints are used for the XOY, XOY and YOZ planes of the 1 / 8 explosion field, and transmission boundaries are used for other surfaces to simulate infinite air domains, that is, in the simulation process of the explosion field, the explosion shock wave propagates from the inside of the calculation domain and does not generate reflections on the boundaries;

[0022] Among them, in the explosion mode BlastFoam, the explosive and air are set as uniform continuous media, and the material model of the explosive is described by the JWL state control equation, which is expressed as

[0023] ;

[0024] in, Indicates the detonation pressure, in Pa; is the state control equation coefficient; is the relative volume of explosive; is the initial internal energy of the explosive;

[0025] Among them, in the explosion mode BlastFoam, the pressure change equation of the explosion shock wave during the outward propagation process is expressed as:

[0026] ;

[0027] in, and denote the pressure and specific volume of the explosion products respectively; It is a multi-party index, which is related to the composition and density of the explosion products. The greater the density, The larger the value; Indicates constant.

[0028] In one of the embodiments, the method further comprises: using an adaptive grid for simulation in the explosion mode BlastFoam, wherein a refined grid is used in the explosion center area, and a sparse grid is used in the non-explosion area.

[0029] In one embodiment, the operation results of the explosion mode are viewed using visualization software, and the coupling time between the WRF_LES mode and the explosion mode is determined according to the preset distance and pressure constraints. At the coupling time, the partial explosion fields are averaged and spliced ​​in turn to obtain a complete explosion field, including:

[0030] The visualization software Paraview is used to view the operation results of the explosion mode BlastFoam, and the coupling time between the WRF_LES mode and the explosion mode is determined according to the preset distance and pressure constraints; the distance and pressure constraints are expressed as

[0031] ;

[0032] ;

[0033] in, Respectively represent the propagation distance and position of the explosion shock wave in the X, Y, and Z directions at different times; It represents the explosion pressure at different times at each point in the BlastFoam simulation domain; Indicates the atmospheric pressure of the surrounding environment; X, Y, and Z represent the longitude, latitude, and vertical directions respectively; It is expressed as the difference between the maximum explosion pressure and the surrounding atmospheric pressure; Indicates time;

[0034] At the coupling time, the average values ​​of the air pressure, temperature, and three-dimensional wind field of the explosion shock wave generated by the 1 / 8 explosion field established under the explosion mode BlastFoam in the X, Y, and Z directions are calculated and expressed as

[0035] ;

[0036] ;

[0037] ;

[0038] in, Indicates the moment of coupling time; represent the average values ​​of air pressure, temperature and three-dimensional wind field respectively; Respectively represent the explosion shock wave in the X, Y, and Z directions. Air pressure, temperature and three-dimensional wind field at each grid point; represents the number of grid points;

[0039] Through a self-written Python program, the 1 / 8 explosion field after average processing is symmetrically spliced ​​to obtain a complete explosion field. Among them, the wind direction determination rule of the three-dimensional wind field during the explosion field splicing process is expressed as follows:

[0040] ;

[0041] in, They represent the complete longitude wind field, latitude wind field and vertical wind field respectively. They represent the longitude wind field, latitude wind field and vertical wind field in the average processed 1 / 8 explosion field, respectively. Represent the X, Y, and Z directions respectively; X, Y, and Z greater than 0 represent the positive direction, and less than 0 represent the negative direction.

[0042] In one embodiment, the complete explosion field is coupled into the WRF_LES model, and the convective cloud after the explosion is simulated by re-running the WRF_LES model to obtain the physical quantity information of the convective cloud after the explosion, including:

[0043] The complete explosion field is coupled into the WRF_LES model through a self-written Python program, and the convective cloud after the explosion is numerically simulated by re-running the WRF_LES model to obtain the physical quantity information of the convective cloud after the explosion; the time step of the WRF_LES model after the restart is smaller than the time step before the restart, and the other parameters of the WRF_LES model remain unchanged before and after the restart;

[0044] Among them, the physical quantity information of the convective cloud after the explosion includes the rainfall intensity , horizontal divergence , disturbed air pressure and the perturbation of each microphysical quantity , the calculation formulas are expressed as

[0045] ;

[0046] ;

[0047] ;

[0048] ;

[0049] in, represents the accumulated precipitation. and They represent the previous moment and the next moment in the pattern operation process respectively; Indicates horizontal wind; subscript With subscript They represent the explosion test results and the control test, and represent the air pressure in the explosion test and the air pressure in the control test, respectively. and represent the microphysical quantities in the explosion test and the control test respectively; the microphysical quantities of the convective cloud after the explosion Including cloud water mixing ratio , Rainwater mixing ratio , total water mixing ratio , cloud water condensation or evaporation rate , cloud-rain collision rate and cloud-rain automatic conversion rate .

[0050] A numerical simulation device for explosion-affected convective clouds, the device comprising:

[0051] The numerical simulation module of convective clouds before explosion is used to download and obtain the sounding data within the target three-dimensional space, and use the sounding data as the input parameters of numerical simulation to simulate the convective clouds before explosion in WRF_LES mode;

[0052] The explosion simulation calculation module is used to obtain the parameter field of the simulated convective cloud at the set explosion time and explosion position in the WRF_LES mode, use the parameter field as the initial explosion field, and establish a partial explosion field with the explosive as the center in the explosion mode and simulate and calculate the explosion shock wave to obtain the physical quantity information of the partial explosion field;

[0053] The coupling module is used to view the operation results of the explosion mode using visualization software, and determine the coupling time between the WRF_LES mode and the explosion mode according to the preset distance and pressure constraints. At the coupling time, the partial explosion fields are averaged and spliced ​​in turn to obtain a complete explosion field.

[0054] The post-explosion convective cloud numerical simulation module is used to couple the complete explosion field into the WRF_LES model, and simulate the post-explosion convective cloud by re-running the WRF_LES model to obtain the physical quantity information of the post-explosion convective cloud.

[0055] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0056] Download and obtain the sounding data within the target three-dimensional space, and use the sounding data as the input parameters of the numerical simulation to simulate the convective clouds before the explosion in the WRF_LES mode;

[0057] In the WRF_LES mode, the parameter field of the simulated convective cloud at the set explosion time and explosion position is obtained, and the parameter field is used as the initial explosion field. In the explosion mode, a partial explosion field is established with the explosive as the center and the explosion shock wave is simulated and calculated to obtain the physical quantity information of the partial explosion field.

[0058] Use visualization software to view the operation results of the explosion mode, and determine the coupling time between the WRF_LES mode and the explosion mode according to the preset distance and pressure constraints. At the coupling time, average and splice the partial explosion fields in turn to obtain a complete explosion field.

[0059] The complete explosion field is coupled into the WRF_LES model, and the convective cloud after the explosion is simulated by re-running the WRF_LES model to obtain the physical quantity information of the convective cloud after the explosion.

[0060] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the following steps:

[0061] Download and obtain the sounding data within the target three-dimensional space, and use the sounding data as the input parameters of the numerical simulation to simulate the convective clouds before the explosion in the WRF_LES mode;

[0062] In the WRF_LES mode, the parameter field of the simulated convective cloud at the set explosion time and explosion position is obtained, and the parameter field is used as the initial explosion field. In the explosion mode, a partial explosion field is established with the explosive as the center and the explosion shock wave is simulated and calculated to obtain the physical quantity information of the partial explosion field.

[0063] Use visualization software to view the operation results of the explosion mode, and determine the coupling time between the WRF_LES mode and the explosion mode according to the preset distance and pressure constraints. At the coupling time, average and splice the partial explosion fields in turn to obtain a complete explosion field.

[0064] The complete explosion field is coupled into the WRF_LES model, and the convective cloud after the explosion is simulated by re-running the WRF_LES model to obtain the physical quantity information of the convective cloud after the explosion.

[0065] The above-mentioned method, device, equipment and medium for numerical simulation of explosion-affected convective clouds have the following technical effects compared with the prior art:

[0066] 1. In three-dimensional space, by coupling the small-scale, high-resolution explosion model into the large-scale, low-resolution WRF_LES model, the propagation effect of the explosion shock wave in the atmosphere can be more realistically reflected, thereby accurately simulating and describing the impact of the explosion on convective clouds.

[0067] 2. In the explosion mode, a partial explosion field is first established, and only the detailed dynamic process of the explosion center area is simulated, which reduces the computational load of explosion field modeling. After determining the coupling time, the symmetry is used to average and splice the partial explosion fields, thereby avoiding repeated calculation of the fine details of the entire explosion field and improving the simulation calculation efficiency.

[0068] 3. In order to deepen the simulation of the macro-micro impact of the explosion on convective clouds, when simulating the convective clouds before the explosion in the WRF_LES mode, the mass concentration and number concentration of water substances in the convective clouds are calculated and output, so that the generation and consumption of water substances such as cloud droplets and ice crystals can be quantified. When simulating the convective clouds after the explosion in the WRF_LES mode, the rain intensity, horizontal divergence, disturbance pressure and disturbance of each microphysical quantity of the convective clouds are calculated and output, which can study the impact of the explosion shock wave on the motion of cloud particles in more detail and accurately. By calculating and analyzing the disturbance of each microphysical quantity after the explosion, the linkage analysis and fine coupling of the macroscopic dynamic field (such as rain intensity, divergence, etc.) and the microscopic physical process (such as cloud water condensation or evaporation rate, cloud-rain collision rate and cloud-rain automatic conversion rate, etc.) are realized, which effectively reveals how the macroscopic disturbance generated by the explosion in the atmosphere affects the distribution and motion of microscopic particles, so that the impact of the explosion on cloud precipitation can be accurately simulated. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 A schematic flow chart of a numerical simulation method for explosion-affected convective clouds in one embodiment;

[0070] Figure 2 A schematic diagram of the change of air pressure over time during the outward propagation of an explosion shock wave in one embodiment;

[0071] Figure 3 The schematic diagram of the operation result of the explosion pressure of 10kgTNT explosive simulated by BlastFoam in one embodiment; wherein, Figure 3 (a) is the running result after running for 0.005s. Figure 3 (b) is the running result after running for 0.015s. Figure 3 (c) is the running result after running for 0.025s. Figure 3 (d) is the running result after running for 0.035s;

[0072] Figure 4 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0073] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0074] In one embodiment, Figure 1 As shown, a numerical simulation method for explosion impact on convective clouds is provided, comprising the following steps:

[0075] Step S1, download and obtain the sounding data within the target three-dimensional space, and use the sounding data as the input parameters of the numerical simulation to simulate the convective clouds before the explosion in the WRF_LES mode.

[0076] Specifically, the case simulated by WRF_LES is an ideal case, so only sounding data are needed to drive the model operation. Five physical quantities, namely altitude, potential temperature, water vapor mixing ratio, longitude wind and latitudinal wind, are selected from the sounding data as input parameters for numerical simulation.

[0077] Among them, WRF_LES means that the Large Eddy Simulation (LES) method is used to simulate turbulence phenomena in the atmosphere under the framework of Weather Research and Forecasting Model (WRF).

[0078] Specifically, the simulation of convective clouds before the explosion in the WRF_LES mode includes:

[0079] In the WRF_LES mode, numerical simulation of convective clouds before the explosion is performed according to the set grid range, simulation time, horizontal spatial resolution, number of horizontal grid points, number of vertical layers, model top height, vertical resolution and time step. During the simulation, the microphysics scheme selects the Thompson scheme and turns off the radiation transfer scheme. Among them, the Thompson scheme is used to simulate the generation, consumption and mutual conversion of water substances in different phases in the cloud. It is a high-resolution microphysics model suitable for precipitation and cloud microphysics simulation in the WRF model.

[0080] In this embodiment, the specific grid range is set to 10 km × 10 km, the simulation time is 3 hours, the horizontal spatial resolution is 100 m, the number of horizontal grid points is set to 101 × 101, the vertical layer is 180 layers, the model top height is 10 km, the vertical resolution is about 30 m, and the time step is 0.5 s.

[0081] Furthermore, in order to deepen the understanding of the macro- and micro-effects of the explosion on convective clouds, the mass concentration and number concentration of water substances in the simulated convective clouds are calculated and output in the WRF_LES mode, which is expressed as

[0082] ;

[0083] ;

[0084] in, Represents water in convective clouds The mass concentration and number concentration of water substances Includes water vapor, cloud droplets, raindrops, ice crystals, snow crystals, graupel and hail; Represents the mass concentration and number concentration of water substances over time changes; represents the advection term, represents the three-dimensional wind field; represents the diffusion term; Represents microphysical items. The specific microphysical processes of microphysical items are output in the microphysical scheme, including cloud water condensation or evaporation, cloud-rain automatic conversion, cloud-rain collision, raindrop evaporation, and raindrop falling process; Represents a 3D gradient operator.

[0085] Step S2, in the WRF_LES mode, obtain the parameter field of the simulated convective cloud at the set explosion time and explosion position, use the parameter field as the initial explosion field, and in the explosion mode, establish a partial explosion field with the explosive as the center and simulate and calculate the explosion shock wave to obtain the physical quantity information of the partial explosion field.

[0086] Specifically, the parameter field of the simulated convective cloud at the set explosion time and explosion location is first obtained in the WRF_LES mode. The parameter field includes the air pressure, temperature, density and three-dimensional wind field of the convective cloud, and the parameter field is used as the initial explosion field.

[0087] Then, the BlastFoam explosion mode is selected. BlastFoam is suitable for high explosive detonation, explosion safety and air explosion, as well as general compressible flow. In the explosion mode BlastFoam, a 1 / 8 explosion field is established with TNT (trinitrotoluene) explosive as the center and the explosion shock wave is simulated and calculated to obtain the physical quantity information of the 1 / 8 explosion field, including air pressure, temperature and three-dimensional wind field. Among them, when establishing a 1 / 8 explosion field with the explosive as the center, symmetry constraints are used for the XOY, XOY, and YOZ planes of the 1 / 8 explosion field, and transmission boundaries are used for other surfaces to simulate infinite air domains, that is, during the simulation of the explosion field, the explosion shock wave propagates from the inside of the calculation domain and does not reflect on the boundary. In this embodiment, adaptive grids are used for simulation in the explosion mode BlastFoam, where a refined grid is used in the explosion center area and a sparse grid is used in the non-explosion area. The calculation domain of BlastFoam is set to 0.5 km×0.5 km×0.5 km, and the TNT explosive is a cube with a size of 0.3 m×0.15 m×0.15 m. The maximum resolution of the explosion area is 0.3 m, the time step is 1 μs, and the simulation time is 0.3 s.

[0088] Among them, in the explosion mode BlastFoam, TNT explosives and air are set as uniform continuous media, and the material model of TNT explosives is described by the JWL (Jones-Wilkins-Lee) state control equation, which is expressed as

[0089] ;

[0090] in, Indicates the detonation pressure, in Pa; is the state control equation coefficient; is the relative volume of explosive; is the initial internal energy of the explosive. The JWL state control equation is a semi-empirical state equation that does not explicitly contain chemical reactions and whose parameters are determined by experimental methods. It can more accurately describe the expansion-driven work process of detonation products.

[0091] Specifically, the material parameters of TNT explosives in this embodiment are as follows: 1630 kg m -3 ; 373.77 GPa and 374.71 GPa respectively; They are 4.15, 0.9 and 0.35 respectively; 9 GJ m -3 .

[0092] Among them, in the explosion mode BlastFoam, the pressure change equation of the explosion shock wave during the outward propagation process is expressed as:

[0093] ;

[0094] in, and They represent the pressure and specific volume (i.e. the volume occupied by a unit mass of a substance) of the explosion products respectively; It is a multi-party index, which is related to the composition and density of the explosion products. The greater the density, The larger the value; Indicates constant.

[0095] The pressure of the explosion shock wave changes with time as it propagates outward. Figure 2 As shown, the explosion shock wave passes through a certain period of time When reaching a certain position, the pressure after time Atmospheric pressure Jump to maximum value The difference between this maximum value and the atmospheric pressure is called the incident overpressure peak ; then decays rapidly and over time Then it drops to negative overpressure and finally returns to atmospheric pressure We need to set the pressure between 0 and the incident overpressure peak A time point during this period is taken as the coupling time between the BlastFoam mode and the WRF_LES mode. The selected coupling time meets the following two requirements: 1) The duration of the explosion shock wave should not be too short to avoid the impact range in WRF_LES being too small or even less than a grid scale, thereby causing local effect distortion of LES; 2) The duration of the explosion shock wave should not be too long to avoid the shock wave propagating outward for a certain distance before the coupling time point. The impact of the shock wave change in this distance on the cloud is unknown, resulting in uncertainty in the initial conditions affecting the cloud and increasing the error of the simulation results.

[0096] Furthermore, in addition to BlastFoam, other explosion modes can also be used, such as the nonlinear explicit dynamic analysis program LS-DYNA, the explicit finite element analysis program AUTODYN for analyzing solid-liquid-gas interactions, the 3D modeling software FLACS, and the large-scale general three-dimensional finite element program MSCDytran for analyzing highly nonlinear and transient dynamic responses. These models can replace the explosion mode BlastFoam in the present invention to simulate the changes in air pressure, temperature, density, and wind field in the area through which the shock wave passes after the explosion of the explosives.

[0097] Step S3, using visualization software to view the operation results of the explosion mode, and determine the coupling time between the WRF_LES mode and the explosion mode according to the preset distance and pressure constraints, and at the coupling time, average and splice the partial explosion fields in turn to obtain a complete explosion field.

[0098] Specifically, we first use the visualization software Paraview to view the running results of the explosion mode BlastFoam. The running results are as follows: Figure 3 As shown in the figure, the coupling time between the WRF_LES mode and the explosion mode is determined according to the preset distance and pressure constraints; where the distance and pressure constraints are expressed as

[0099] ;

[0100] ;

[0101] in, Respectively represent the propagation distance and position of the explosion shock wave in the X, Y, and Z directions at different times; It represents the explosion pressure at different times at each point in the BlastFoam simulation domain; Indicates the atmospheric pressure of the surrounding environment; X, Y, and Z represent the longitude, latitude, and vertical directions respectively; It is expressed as the difference between the maximum explosion pressure and the surrounding atmospheric pressure; Indicates time.

[0102] Since BlastFoam is a small-scale and high-resolution mode, and WRF_LES is relatively a large-scale and low-resolution mode, in order to effectively integrate the simulation results of BlastFoam into WRF_LES, after determining the coupling time, it is necessary to average the explosion field through a self-written Python program. The specific steps are as follows:

[0103] At the coupling time, the average values ​​of the air pressure, temperature, and three-dimensional wind field of the explosion shock wave generated by the 1 / 8 explosion field established under the explosion mode BlastFoam in the X, Y, and Z directions are calculated and expressed as

[0104] ;

[0105] ;

[0106] ;

[0107] in, Indicates the moment of coupling time; represent the average values ​​of air pressure, temperature and three-dimensional wind field respectively; Respectively represent the explosion shock wave in the X, Y, and Z directions. Air pressure, temperature and three-dimensional wind field at each grid point; Represents the number of grid points.

[0108] Through a self-written Python program, the 1 / 8 explosion field after average processing is symmetrically spliced ​​to obtain a complete explosion field. Among them, the wind direction determination rule of the three-dimensional wind field during the explosion field splicing process is expressed as follows:

[0109] ;

[0110] in, They represent the complete longitude wind field, latitude wind field and vertical wind field respectively. They represent the longitude wind field, latitude wind field and vertical wind field in the average processed 1 / 8 explosion field, respectively. Represent the X, Y, and Z directions respectively; X, Y, and Z greater than 0 represent the positive direction, and less than 0 represent the negative direction.

[0111] Step S4, coupling the complete explosion field into the WRF_LES model, and re-running the WRF_LES model to simulate the convective clouds after the explosion, to obtain the physical quantity information of the convective clouds after the explosion.

[0112] Specifically, the complete explosion field is coupled into the WRF_LES model through a self-written Python program, and the convective cloud after the explosion is numerically simulated by re-running the WRF_LES model to obtain the physical quantity information of the convective cloud after the explosion; wherein, in order to avoid the problem of fluid instability in the calculation process of WRF_LES, the time step of the WRF_LES model after restart is smaller than the time step before restart, and other parameters of the WRF_LES model remain unchanged before and after restart. In this embodiment, the time step of the WRF_LES model after restart is changed to 0.1 s or even smaller.

[0113] Among them, the physical quantity information of the convective cloud after the explosion includes the rainfall intensity , horizontal divergence , disturbed air pressure and the perturbation of each microphysical quantity , the calculation formulas are expressed as

[0114] ;

[0115] ;

[0116] ;

[0117] ;

[0118] in, represents the accumulated precipitation. and They represent the previous moment and the next moment in the pattern operation process respectively; Indicates horizontal wind; subscript With subscript They represent the explosion test results and the control test, and represent the air pressure in the explosion test and the air pressure in the control test, respectively. and represent the microphysical quantities in the explosion test and the control test respectively; the microphysical quantities of the convective cloud after the explosion Including cloud water mixing ratio , Rainwater mixing ratio , total water mixing ratio , cloud water condensation or evaporation rate , cloud-rain collision rate and cloud-rain automatic conversion rate .

[0119] The above-mentioned numerical simulation method of the impact of explosion on convective clouds combines the explosion mode BlastFoam and the WRF_LES mode to carry out a three-dimensional numerical simulation of how the explosion affects convective clouds, filling the current gap in the field of three-dimensional numerical simulation of the interaction between explosion shock waves and cloud particles, and realizing multi-scale coupling from small scale to large scale and from macro to micro.

[0120] In one embodiment, a numerical simulation device for explosion-affected convective clouds is provided, comprising:

[0121] The numerical simulation module of convective clouds before explosion is used to download and obtain the sounding data within the target three-dimensional space, and use the sounding data as the input parameters of numerical simulation to simulate the convective clouds before explosion in WRF_LES mode;

[0122] The explosion simulation calculation module is used to obtain the parameter field of the simulated convective cloud at the set explosion time and explosion position in the WRF_LES mode, use the parameter field as the initial explosion field, and establish a partial explosion field with the explosive as the center in the explosion mode and simulate and calculate the explosion shock wave to obtain the physical quantity information of the partial explosion field;

[0123] The coupling module is used to view the operation results of the explosion mode using visualization software, and determine the coupling time between the WRF_LES mode and the explosion mode according to the preset distance and pressure constraints. At the coupling time, the partial explosion fields are averaged and spliced ​​in turn to obtain a complete explosion field.

[0124] The post-explosion convective cloud numerical simulation module is used to couple the complete explosion field into the WRF_LES model, and simulate the post-explosion convective cloud by re-running the WRF_LES model to obtain the physical quantity information of the post-explosion convective cloud.

[0125] The specific definition of the numerical simulation device for the effect of explosion on convective clouds can be found in the definition of the numerical simulation method for the effect of explosion on convective clouds mentioned above, which will not be repeated here. Each module in the above-mentioned numerical simulation device for the effect of explosion on convective clouds can be implemented in whole or in part by software, hardware and a combination thereof. Each of the above-mentioned modules can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute the operations corresponding to each of the above modules.

[0126] In one embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as follows: Figure 4 As shown. The computer device includes a processor, a memory, a network interface, a display screen and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a numerical simulation method of explosion-affected convective clouds is implemented. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covered on the display screen, or a key, trackball or touchpad set on the computer device housing, or an external keyboard, touchpad or mouse, etc.

[0127] Those skilled in the art will understand that Figure 4 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0128] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0129] Download and obtain the sounding data within the target three-dimensional space, and use the sounding data as the input parameters of the numerical simulation to simulate the convective clouds before the explosion in the WRF_LES mode;

[0130] In the WRF_LES mode, the parameter field of the simulated convective cloud at the set explosion time and explosion position is obtained, and the parameter field is used as the initial explosion field. In the explosion mode, a partial explosion field is established with the explosive as the center and the explosion shock wave is simulated and calculated to obtain the physical quantity information of the partial explosion field.

[0131] Use visualization software to view the operation results of the explosion mode, and determine the coupling time between the WRF_LES mode and the explosion mode according to the preset distance and pressure constraints. At the coupling time, average and splice the partial explosion fields in turn to obtain a complete explosion field.

[0132] The complete explosion field is coupled into the WRF_LES model, and the convective cloud after the explosion is simulated by re-running the WRF_LES model to obtain the physical quantity information of the convective cloud after the explosion.

[0133] In one embodiment, a computer readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented:

[0134] Download and obtain the sounding data within the target three-dimensional space, and use the sounding data as the input parameters of the numerical simulation to simulate the convective clouds before the explosion in the WRF_LES mode;

[0135] In the WRF_LES mode, the parameter field of the simulated convective cloud at the set explosion time and explosion position is obtained, and the parameter field is used as the initial explosion field. In the explosion mode, a partial explosion field is established with the explosive as the center and the explosion shock wave is simulated and calculated to obtain the physical quantity information of the partial explosion field.

[0136] Use visualization software to view the operation results of the explosion mode, and determine the coupling time between the WRF_LES mode and the explosion mode according to the preset distance and pressure constraints. At the coupling time, average and splice the partial explosion fields in turn to obtain a complete explosion field.

[0137] The complete explosion field is coupled into the WRF_LES model, and the convective cloud after the explosion is simulated by re-running the WRF_LES model to obtain the physical quantity information of the convective cloud after the explosion.

[0138] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0139] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0140] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A numerical simulation method for explosion-affected convective clouds, characterized in that: The method comprises: Download and obtain the sounding data within the target three-dimensional space, and use the sounding data as the input parameters of the numerical simulation to simulate the convective clouds before the explosion in the WRF_LES mode; In the WRF_LES mode, the parameter field of the simulated convective cloud at the set explosion time and explosion position is obtained, and the parameter field is used as the initial explosion field. In the explosion mode, a partial explosion field is established with the explosive as the center and the explosion shock wave is simulated and calculated to obtain the physical quantity information of the partial explosion field. The operation results of the explosion mode are viewed using visualization software, and the coupling time between the WRF_LES mode and the explosion mode is determined according to the preset distance and pressure constraints. At the coupling time, the partial explosion fields are averaged and spliced ​​in turn to obtain a complete explosion field. The complete explosion field is coupled into the WRF_LES model, and the convective cloud after the explosion is simulated by re-running the WRF_LES model to obtain the physical quantity information of the convective cloud after the explosion.

2. The method according to claim 1, characterized in that Download and obtain the sounding data within the target three-dimensional space, and use the sounding data as input parameters for numerical simulation, including: The sounding data within the target three-dimensional space are downloaded and acquired, and five physical quantities, namely, height, potential temperature, water vapor mixing ratio, longitude wind and latitude wind, are selected from the sounding data as input parameters for numerical simulation.

3. The method according to claim 1, characterized in that Simulation of convective clouds before explosion in WRF_LES mode, including: In the WRF_LES mode, numerical simulation of convective clouds before the explosion is performed according to the set grid range, simulation time, horizontal spatial resolution, number of horizontal grid points, number of vertical layers, model top height, vertical resolution and time step. During the simulation, the microphysics scheme selects the Thompson scheme and closes the radiation transfer scheme. Furthermore, the source and sink terms of the mass concentration and number concentration of water species in the simulated convective clouds are calculated and output in the WRF_LES mode, expressed as ； ； in, Represents water in convective clouds The mass concentration and number concentration of water substances Includes water vapor, cloud droplets, raindrops, ice crystals, snow crystals, graupel and hail; Represents the mass concentration and number concentration of water substances over time changes; represents the advection term, represents the three-dimensional wind field; represents the diffusion term; Represents microphysical terms. The specific microphysical processes of microphysical terms are output in the microphysical scheme, including cloud water condensation or evaporation, cloud-rain automatic conversion, cloud-rain collision, raindrop evaporation, and raindrop falling process; Represents a 3D gradient operator.

4. The method according to claim 1, characterized in that: In the WRF_LES mode, the parameter field of the simulated convective cloud at the set explosion time and explosion position is obtained, and the parameter field is used as the initial explosion field. In the explosion mode, a partial explosion field is established with the explosive as the center and the explosion shock wave is simulated and calculated to obtain the physical quantity information of the partial explosion field, including: In the WRF_LES mode, the parameter field of the simulated convective cloud at the set explosion time and explosion position is obtained, wherein the parameter field includes the air pressure, temperature, density and three-dimensional wind field of the convective cloud, and the parameter field is used as the initial explosion field; In the explosion mode BlastFoam, a 1 / 8 explosion field is established with the explosive as the center and the explosion shock wave is simulated and calculated to obtain the physical quantity information of the 1 / 8 explosion field, including air pressure, temperature and three-dimensional wind field; when establishing the 1 / 8 explosion field with the explosive as the center, symmetry constraints are used for the XOY, XOY and YOZ planes of the 1 / 8 explosion field, and transmission boundaries are used for other surfaces to simulate infinite air domains, that is, in the simulation process of the explosion field, the explosion shock wave propagates from the inside of the calculation domain and does not generate reflections on the boundaries; Among them, in the explosion mode BlastFoam, the explosive and air are set as uniform continuous media, and the material model of the explosive is described by the JWL state control equation, which is expressed as ； in, Indicates the detonation pressure, in Pa; is the state control equation coefficient; is the relative volume of explosive; is the initial internal energy of the explosive; Among them, in the explosion mode BlastFoam, the pressure change equation of the explosion shock wave during the outward propagation process is expressed as: ； in, and denote the pressure and specific volume of the explosion products respectively; It is a multi-party index, which is related to the composition and density of the explosion products. The greater the density, The larger the value; Indicates constant.

5. The method according to claim 4, characterized in that The method further comprises: using adaptive grids for simulation in the explosion mode BlastFoam, wherein a refined grid is used in the explosion center area, and a sparse grid is used in the non-explosion area.

6. The method according to claim 4, characterized in that The operation results of the explosion mode are viewed using visualization software, and the coupling time between the WRF_LES mode and the explosion mode is determined according to the preset distance and pressure constraints. At the coupling time, the partial explosion fields are averaged and spliced ​​in turn to obtain a complete explosion field, including: The visualization software Paraview was used to view the operation results of the explosion mode BlastFoam, and the coupling time between the WRF_LES mode and the explosion mode was determined according to the preset distance and pressure constraints; wherein the distance and pressure constraints are expressed as ； ； in, Respectively represent the propagation distance and position of the explosion shock wave in the X, Y, and Z directions at different times; It represents the explosion pressure at different times at each point in the BlastFoam simulation domain; Indicates the atmospheric pressure of the surrounding environment; X, Y, and Z represent the longitude, latitude, and vertical directions respectively; It is expressed as the difference between the maximum explosion pressure and the surrounding atmospheric pressure; Indicates time; At the coupling time, the average values ​​of the air pressure, temperature, and three-dimensional wind field of the explosion shock wave generated by the 1 / 8 explosion field established under the explosion mode BlastFoam in the X, Y, and Z directions are calculated and expressed as ； ； ； in, Indicates the moment of coupling time; represent the average values ​​of air pressure, temperature and three-dimensional wind field respectively; Respectively represent the explosion shock wave in the X, Y, and Z directions. Air pressure, temperature and three-dimensional wind field at each grid point; represents the number of grid points; Through a self-written Python program, the 1 / 8 explosion field after average processing is symmetrically spliced ​​to obtain a complete explosion field. Among them, the wind direction determination rule of the three-dimensional wind field during the explosion field splicing process is expressed as follows: ； in, They represent the complete longitude wind field, latitude wind field and vertical wind field respectively. They represent the longitude wind field, latitude wind field and vertical wind field in the average processed 1 / 8 explosion field, respectively. Represent the X, Y, and Z directions respectively; X, Y, and Z greater than 0 represent the positive direction, and less than 0 represent the negative direction.

7. The method according to claim 6, characterized in that The complete explosion field is coupled into the WRF_LES model, and the convective cloud after the explosion is simulated by re-running the WRF_LES model to obtain the physical quantity information of the convective cloud after the explosion, including: The complete explosion field is coupled into the WRF_LES model through a self-written Python program, and the numerical simulation of the convective cloud after the explosion is performed by re-running the WRF_LES model to obtain the physical quantity information of the convective cloud after the explosion; wherein, the time step of the WRF_LES model after the restart is smaller than the time step before the restart, and other parameters of the WRF_LES model remain unchanged before and after the restart; Among them, the physical quantity information of the convective cloud after the explosion includes the rainfall intensity , horizontal divergence , disturbed air pressure and the perturbation of each microphysical quantity , the calculation formulas are expressed as ； ； ； ； in, represents the accumulated precipitation. and They represent the previous moment and the next moment in the pattern operation process respectively; Indicates horizontal wind; subscript With subscript They represent the explosion test results and the control test, and represent the air pressure in the explosion test and the air pressure in the control test, respectively. and represent the microphysical quantities in the explosion test and the control test respectively; the microphysical quantities of the convective cloud after the explosion Including cloud water mixing ratio , Rainwater mixing ratio , total water mixing ratio , cloud water condensation or evaporation rate , cloud-rain collision rate and cloud-rain automatic conversion rate .

8. A numerical simulation device for explosion-affected convective clouds, characterized in that: The device comprises: The numerical simulation module of convective clouds before explosion is used to download and obtain the sounding data within the target three-dimensional space, and use the sounding data as the input parameters of the numerical simulation to simulate the convective clouds before explosion in the WRF_LES mode; The explosion simulation calculation module is used to obtain the parameter field of the simulated convective cloud at the set explosion time and explosion position in the WRF_LES mode, use the parameter field as the initial explosion field, and establish a partial explosion field with the explosive as the center in the explosion mode and simulate and calculate the explosion shock wave to obtain the physical quantity information of the partial explosion field; A coupling module is used to view the operation results of the explosion mode using visualization software, and determine the coupling time between the WRF_LES mode and the explosion mode according to preset distance and pressure constraints, and at the coupling time, average and splice the partial explosion fields in turn to obtain a complete explosion field; The post-explosion convective cloud numerical simulation module is used to couple the complete explosion field into the WRF_LES model, and simulate the post-explosion convective cloud by re-running the WRF_LES model to obtain the physical quantity information of the post-explosion convective cloud.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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