A method for calculating the impact sensitivity of fireworks and firecracker charges and related equipment

Abstract

The present application relates to the technical field of energetic material safety detection, and discloses a calculation method for impact sensitivity of fireworks and firecrackers and related equipment, which comprises the following steps: obtaining micro-characterization data of a sample to be measured and a reference sample with the same formula; determining an impact action boundary according to drop hammer test conditions; respectively reconstructing a local filling model of the sample to be measured and a local filling model of the reference sample; respectively solving particle contact responses of the local filling model of the sample to be measured and the local filling model of the reference sample under the impact action boundary to obtain corresponding contact dissipation energy distributions; respectively calculating a thermal spot temperature rise history of the sample to be measured and a thermal spot temperature rise history of the reference sample according to the contact dissipation energy distributions and thermal physical property data of the samples; calibrating a firing critical state from reference firing data and the thermal spot temperature rise history of the reference sample, and defining a reverse starting point with a nominal sensitivity of the sample to be measured to obtain a calculated impact sensitivity value of the sample to be measured; and the present application is beneficial to making the impact sensitivity calculation reflect actual loading conditions of the samples.

Description

Technical Field

[0001] This invention relates to the field of energetic material safety testing technology, and more specifically, to a method and related equipment for calculating the impact sensitivity of fireworks and firecracker agents. Background Technology

[0002] The impact sensitivity of fireworks and firecracker agents is used to characterize the susceptibility of the agent to ignition under a falling hammer impact load, and is an important parameter in the evaluation of the mechanical sensitivity of the agent and process safety control. Current evaluations typically determine the characteristic drop height based on standard falling hammer impact tests, and characterize the macroscopic sensitivity of the sample by the ignition state under specified loading conditions. While this test system has engineering applicability, the test results mainly reflect the overall performance of the sample, and are insufficient in characterizing the changes in load response caused by microscopic differences in the internal packing of the agent layer.

[0003] Current sensitivity calculations often rely on nominal formulations, overall thermochemical properties, or descriptions of individual energetic components to establish predictive relationships, typically treating the propellant as a homogeneous computational object. Fireworks and firecracker propellants are multi-component particulate mixtures. After the falling hammer load enters the propellant layer, it is transmitted along the particle contact structure. The local contact state affects mechanical energy dissipation and the initial thermal response. Samples with the same nominal formulation may exhibit different impact responses due to variations in particle packing states within the loaded region, making calculations based on the overall formulation difficult to characterize sensitivity differences under actual loading conditions. Summary of the Invention

[0004] To overcome the above-mentioned deficiencies of the prior art, embodiments of the present invention provide a method and related equipment for calculating the impact sensitivity of fireworks and firecracker agents.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A method for calculating the impact sensitivity of fireworks and firecracker agents, comprising:

[0007] Obtain detailed characterization data of the sample to be tested and the reference sample with the same formulation, and read the drop hammer test conditions, reference ignition data, agent thermophysical property data and the nominal sensitivity of the sample to be tested;

[0008] The impact boundary was determined according to the drop hammer test conditions, and the local loading model of the sample to be tested and the local loading model of the reference sample were reconstructed respectively.

[0009] The particle contact response of the local packed model of the test sample and the local packed model of the reference sample were solved under the impact boundary to obtain the corresponding contact dissipation energy distribution.

[0010] Based on the contact dissipation energy distribution and the thermophysical properties of the reagent, the hot spot temperature rise history of the test sample and the hot spot temperature rise history of the reference sample were calculated respectively.

[0011] The critical ignition state is calibrated by referring to ignition data and the hot spot temperature rise history of the reference sample, and the starting point is calculated by inversely determining the nominal sensitivity limit of the sample to be tested, thus obtaining the calculated impact sensitivity value of the sample to be tested.

[0012] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the method described in any of the preceding claims.

[0013] A computer-readable storage medium having a computer program stored thereon, the computer program being executed by a processor to implement the method described in any of the preceding claims.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0015] This invention determines the impact boundary according to the drop hammer test conditions and reconstructs the local filling model of the sample to be tested and the local filling model of the reference sample respectively, so that the sensitivity calculation object is limited to the particle filling state in the actual load area, reducing the masking of local load differences by the overall formula equivalent calculation.

[0016] This invention solves the particle contact response separately under the impact boundary to obtain the corresponding contact dissipation energy distribution, and calculates the hot spot temperature rise history by combining the agent's thermophysical property data, so that the particle force transmission, mechanical energy dissipation and local thermal response under the drop hammer impact load can be connected in the same calculation process.

[0017] This invention calibrates the critical ignition state by using reference ignition data and the hot spot temperature rise history of a reference sample, and then reverses the starting point based on the nominal sensitivity of the sample to be tested to obtain the calculated impact sensitivity value of the sample to be tested. This allows the calculation results to take into account both the ignition basis of the drop hammer test and the local filling differences of the sample to be tested. Attached Figure Description

[0018] Figure 1 A flowchart of a method for calculating the impact sensitivity of fireworks and firecracker agents provided by the present invention;

[0019] Figure 2 A schematic diagram of the structure of an electronic device provided by the present invention;

[0020] Figure 3 This is a schematic diagram of the structure of a computer-readable storage medium provided by the present invention. Detailed Implementation

[0021] 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.

[0022] Example 1

[0023] Please see Figure 1 As shown, this embodiment discloses a method for calculating the impact sensitivity of fireworks and firecracker agents. This method is applicable to the calculation of the impact sensitivity of particulate mixed fireworks and firecracker agents under drop hammer test conditions. The test sample is the agent sample whose impact sensitivity value needs to be determined; the reference sample with the same formulation is an agent sample with the same nominal formulation as the test sample and whose ignition state under drop hammer test conditions has been recorded. The reference sample referred to below refers to the reference sample with the same formulation. The calculation method includes:

[0024] S101: Obtain microscopic characterization data of the sample to be tested and the reference sample with the same formulation, and read the drop hammer test conditions, reference ignition data, agent thermophysical property data and the nominal sensitivity of the sample to be tested;

[0025] S102: Determine the impact boundary according to the drop hammer test conditions, and reconstruct the local loading model of the sample to be tested and the local loading model of the reference sample respectively;

[0026] S103: Solve the particle contact response of the local filling model of the test sample and the local filling model of the reference sample under the impact boundary to obtain the corresponding contact dissipation energy distribution.

[0027] S104: Based on the contact dissipation energy distribution and agent thermophysical property data, calculate the hot spot temperature rise history of the test sample and the hot spot temperature rise history of the reference sample, respectively.

[0028] S105: The critical state of ignition is calibrated by referring to the ignition data and the hot spot temperature rise history of the reference sample, and the starting point is calculated by inversely determining the nominal sensitivity limit of the sample to be tested.

[0029] In step S101, the microstructure characterization data of the sample to be tested and the microstructure characterization data of the reference sample are obtained respectively. The microstructure characterization data comes from the three-dimensional characterization results of the drug layer. After spatial scale calibration, particle boundary identification, and reaction component phase identification, the three-dimensional characterization results form data that can represent the spatial state of the drug particles. This data is used to determine the spatial position of the drug particles in the drug layer, particle boundaries, particle adjacency relationships, and reaction component phase assignments.

[0030] As one implementation method, three-dimensional characterization results can be obtained by scanning the drug layer using three-dimensional non-destructive characterization techniques such as micro-computed tomography (Micro-CT). Phase identification of the reaction components can be determined through image segmentation based on the differences in grayscale or density of different reaction components in the three-dimensional characterization results. The microscopic characterization data of the test sample is used to reconstruct the local packing model of the test sample, and the microscopic characterization data of the reference sample is used to reconstruct the local packing model of the reference sample. The two types of microscopic characterization data are stored separately and participate in subsequent processing according to the spatial coordinate relationships of their respective samples.

[0031] Furthermore, after the microscopic characterization data is generated, a spatial correspondence is established between the surface of the reagent layer, the bearing side of the reagent layer, and the direction of the drop hammer load transfer. The surface of the reagent layer is used to determine the contact projection position of the drop hammer head; the bearing side of the reagent layer is used to determine the termination position of the load-bearing range along the direction of the drop hammer load transfer; and the direction of the drop hammer load transfer is used to determine the direction in which the impacted area extends into the interior of the reagent layer. This spatial correspondence allows the drop hammer test conditions to be mapped into the microscopic characterization data of the test sample and the reference sample, and enables the local loading model to be established based on the actual load-bearing area.

[0032] The drop hammer test conditions are derived from the drop hammer test plan, test records, or corresponding process parameter records. These conditions are used to determine the relative position of the drop hammer head and the surface of the reagent layer, the direction of the drop hammer head's action, the load-bearing state of the reagent layer, and the relationship between the drop hammer input energy and the drop height. For drop hammer tests where impact sensitivity is characterized by a characteristic drop height, the drop hammer input energy is determined by the following formula: ;

[0033] in, Input energy to the falling hammer, For the falling weight, It is the acceleration due to gravity. This represents the drop hammer height. This correspondence is used to convert the drop hammer input energy reaching the ignition critical state into a calculated impact sensitivity value.

[0034] The reference ignition data is derived from the ignition state record of the reference sample under drop hammer test conditions. The reference ignition data corresponds to the reference sample and the corresponding drop hammer input energy, and is used to calibrate the critical ignition state based on the hotspot temperature rise history of the reference sample.

[0035] The thermophysical property data of the reagent corresponds to the reactive components in the microscopic characterization data, and is used to calculate the transient heat transfer response of the contact area of ​​the reactive components after receiving heat input. The thermophysical property data of the reagent can be derived from material test data, formulation basis data, or confirmed thermophysical parameter records, serving as the parameter basis for calculating the hot spot temperature rise history, so that the contact dissipation energy distribution can be converted into the temperature rise history of the contact area of ​​the reactive components.

[0036] The nominal sensitivity of the test sample is the characteristic drop height of the corresponding nominal formulation of the test sample, used to define the starting point for the reverse calculation of the test sample. This data corresponds to the conversion relationship of the drop weight input energy in the drop weight test conditions, and is used to determine the initial drop weight input energy for the reverse calculation.

[0037] The microscopic characterization data refers to three-dimensional characterization data that can characterize the spatial state of drug particles and distinguish the phase affiliation of reaction components. The reference ignition data is the ignition state record of a reference sample with the same formulation under drop hammer test conditions. The nominal sensitivity of the test sample is the characteristic drop height of the nominal formulation corresponding to the test sample.

[0038] The reaction component phase assignment is used to indicate the reaction component phase corresponding to the drug particle or a local region of the particle. For cases where the entire particle corresponds to a single component phase, the reaction component phase assignment is determined according to the entire particle; for cases where identifiable component regions exist within the particle, the reaction component phase assignment is determined according to the identifiable component regions in the three-dimensional characterization data. This process allows the reaction component contact area to be distinguished from other particle contact areas and enables the contact dissipation energy distribution to correspond to the hot spot formation area.

[0039] For example, both the test sample and the reference sample are fireworks and firecracker agents with the same nominal formula. After obtaining three-dimensional characterization results for the two types of samples, the particle positions and reaction component phases within the agent layer can be identified. The ignition state record formed by the reference sample at the corresponding drop height is used as reference ignition data, and the characteristic drop height of the test sample corresponding to the nominal formula is used as the nominal sensitivity of the test sample. After processing, the above data forms the basis for determining the impact boundary, reconstructing the local filling model, calculating the hot spot temperature rise history, and inversely calculating the impact sensitivity value.

[0040] The above data acquisition method allows nominal formula information, reference ignition data, and detailed filling status to enter the same calculation process, ensuring that the impact sensitivity calculation object and calculation parameters have a clear correspondence.

[0041] In step S102, the impact boundary is determined based on the drop hammer test conditions. The impact boundary characterizes the spatial range and load constraint relationship when the drop hammer acts on the reagent layer, corresponding to the drop hammer contact projection, the drop hammer load transfer direction, and the reagent layer bearing state. After determining the impact boundary, it is applied to the mesoscopic characterization data of the test sample and the reference sample, respectively, to obtain the spatial ranges used for model reconstruction, namely, the load ranges of the test sample and the reference sample, as described below. Thus, the test sample and the reference sample form locally packed models under the same drop hammer test conditions, providing a clear foundation for subsequent calculations.

[0042] Specifically, the step of determining the impact boundary according to the drop hammer test conditions and reconstructing the local loading model of the sample to be tested and the local loading model of the reference sample respectively includes:

[0043] By mapping the drop weight test conditions to the microscopic characterization data of the test sample and the reference sample with the same formulation, the load range of the test sample and the load range of the reference sample are obtained.

[0044] As one implementation method, the position of the falling hammer head, the position of the reagent layer surface, the position of the reagent layer bearing side, and the direction of falling hammer load transfer in the falling hammer test conditions are transformed into the coordinate relationship of the microscopic characterization data of the sample under test to determine the load range of the sample under test. Under the same falling hammer test conditions, the above information is transformed into the coordinate relationship of the microscopic characterization data of the reference sample to determine the load range of the reference sample. If the microscopic characterization data of the sample under test and the reference sample have different original coordinates, the reagent layer surface and the reagent layer bearing side are used as the coordinate correction basis, so that the same falling hammer test conditions can be mapped to the two types of microscopic characterization data respectively.

[0045] The load range of the test sample is derived from its microstructural characterization data, and the load range of the reference sample is derived from its microstructural characterization data. Both are limited by the same drop-weight test conditions and retain the particle spatial state of their respective samples. This process ensures that the critical calibration calculation of the reference sample and the inverse sensitivity calculation of the test sample have the same experimental boundaries.

[0046] The mapping of drop hammer test conditions to the microscopic characterization data of the test sample and the reference sample with the same formulation includes:

[0047] The impact area of ​​the test sample and the impact area of ​​the reference sample are determined based on the contact projection between the drop hammer head and the surface of the reagent layer.

[0048] Specifically, based on the contact relationship between the drop hammer and the surface of the reagent layer under drop hammer test conditions, the contact projection of the drop hammer on the reagent layer surface is determined. This contact projection represents the initial range of action of the drop hammer on the reagent layer surface. The contact projection is mapped onto the reagent layer surface in the microscopic characterization data of the sample under test to obtain the impact area of ​​the sample under test; the same contact projection is mapped onto the reagent layer surface in the microscopic characterization data of the reference sample to obtain the impact area of ​​the reference sample.

[0049] For ease of understanding, when the end face of the drop hammer is a planar circle, the contact projection is a circular area corresponding to the shape of the end face. When the surface coordinates of the reagent layer have been determined by three-dimensional characterization data, this circular area is projected onto the reagent layer surface according to the position of the drop hammer, resulting in the impact area of ​​the test sample and the impact area of ​​the reference sample, respectively. The impact area is determined by the contact projection between the drop hammer and the reagent layer surface, giving the load range a clear source of experimental conditions.

[0050] By extending the impact area of ​​the test sample and the impact area of ​​the reference sample along the direction of the falling hammer load transmission, the load range of the test sample and the load range of the reference sample are obtained.

[0051] After the impact area is determined, the load range of the test sample is obtained by extending along the direction of the drop load transfer within the reagent layer of the test sample to the position corresponding to the load-bearing state of the reagent layer, using the impact area of ​​the test sample as the starting region; similarly, the load range of the reference sample is obtained by extending along the direction of the drop load transfer within the reagent layer of the reference sample to the position corresponding to the load-bearing state of the reagent layer. Both the load range of the test sample and the load range of the reference sample are three-dimensional spatial ranges used to define the spatial state of the reagent particles participating in the reconstruction of the local filling model.

[0052] It should be noted that the boundary of the load-bearing area is jointly determined by the impact region, the direction of the drop hammer load transfer, and the load-bearing state of the reagent layer. For cases where the reagent layer bearing side has been determined in the mesoscopic characterization data, the impact region extends along the drop hammer load transfer direction to the reagent layer bearing side; for cases where the effective load depth is limited in the drop hammer test conditions, the impact region extends along the drop hammer load transfer direction to the corresponding effective load depth. This treatment ensures that the load-bearing area corresponds to the drop hammer test conditions, reducing the impact of unloaded areas on subsequent calculations.

[0053] Based on the spatial state of the reagent particles within the loading range of the test sample and the loading range of the reference sample, the local loading models of the test sample and the reference sample are reconstructed respectively.

[0054] Based on the determined loading range, the spatial state of the reagent particles is extracted from the loading range of the test sample, preserving particle boundaries, particle positions, particle adjacency relationships, and the attribution of reactant components, and the local packing model of the test sample is reconstructed. Similarly, the spatial state of the reagent particles is extracted from the loading range of the reference sample, preserving particle boundaries, particle positions, particle adjacency relationships, and the attribution of reactant components, and the local packing model of the reference sample is reconstructed. For particles located at the boundary of the loading range, boundary constraints are determined according to their actual spatial state in the microscopic characterization data, ensuring loading continuity between the local packing model and the reagent layer outside the loading range.

[0055] A localized packing model for the test sample is used to solve for the particle contact response, contact dissipation energy distribution, and hotspot temperature rise history of the test sample. A localized packing model for the reference sample is used to solve for the particle contact response, contact dissipation energy distribution, and hotspot temperature rise history of the reference sample. Both are constrained by the same drop-weight test conditions and retain the actual particle packing state of their respective samples. This model reconstruction method can preserve the microscopic packing differences between the test sample and the reference sample under the same impact boundary.

[0056] In step S103, the impact boundary is used as the loading boundary, and the local loading model of the sample to be tested and the local loading model of the reference sample are used as the calculation objects to solve the transfer process of the input energy of the falling hammer between the drug particles. The particle contact response is used to represent the contact force, relative displacement, and relative motion state formed by the drug particles under impact; the contact dissipation energy distribution is used to represent the spatial distribution and temporal variation of the energy formed by compressive damping, tangential slip, and collision dissipation in the local loading model during particle contact.

[0057] Furthermore, the energy input from the drop hammer is converted into a loading process and applied to the impact side of the locally packed model. Bearing constraints corresponding to the drop hammer test conditions are applied to the bearing side of the locally packed model. The locally packed model of the test sample is solved according to the particle spatial state within the load-bearing range of the test sample to obtain the contact dissipation energy distribution corresponding to the test sample; the locally packed model of the reference sample is solved according to the particle spatial state within the load-bearing range of the reference sample to obtain the contact dissipation energy distribution corresponding to the reference sample. This calculation allows the hot spot temperature rise history to be based on the actual particle contact force transmission process.

[0058] Specifically, the step of solving the particle contact response of the local packing model of the test sample and the local packing model of the reference sample under the impact boundary includes:

[0059] The particle contact response of the test sample and the reference sample is obtained by solving the particle contact response of the test sample and the reference sample under the impact boundary.

[0060] As one implementation method, particle contact calculation relationships are established in the localized loading models of the sample under test and the reference sample, respectively. For adjacent particles, the contact interface is determined based on the positional relationship between particle boundaries; for particles adjacent to the impacted or load-bearing side, the boundary contact relationship is determined based on the impact boundary and load-bearing constraints. During loading, the normal contact state and tangential relative motion state at the particle contact interface are solved according to the calculation time increment to form the corresponding particle contact response.

[0061] The particle contact response of the test sample and the particle contact response of the reference sample were obtained by solving their respective local packing models. Both used the same impact boundary, but the particle spatial state, the phase assignment of the reactants, and the distribution of the contact interface were derived from different samples. This treatment can reflect the influence of different local packing states on impact force transmission and energy dissipation under the same formulation conditions.

[0062] The step of solving the particle contact response of the local packing model of the test sample and the local packing model of the reference sample under the impact boundary includes:

[0063] The particle contact interface involved in impact force transmission is determined in the local loading model of the sample to be tested and the local loading model of the reference sample.

[0064] Specifically, in the local loading model of the sample to be tested, the contact interface of the particles participating in the impact force transmission in the sample to be tested is determined according to the contact relationship or the closable gap between the particle boundaries within the load range of the sample to be tested; in the local loading model of the reference sample, the contact interface of the particles participating in the impact force transmission in the reference sample is determined according to the contact relationship or the closable gap between the particle boundaries within the load range of the reference sample.

[0065] For particles that are already in contact in the initial state, the contact surface between adjacent particle boundaries is directly used as the particle contact interface; for particles that have gaps in the initial state but come into contact during impact loading, the contact surface formed after the gap closes is used as the particle contact interface; for particles that interact with the impacted side or the load-bearing side, the interaction surface between the particle boundary and the corresponding boundary is used as the boundary contact interface. This process can locate the particle contact interfaces that actually participate in force transmission within the load-bearing range, making the contact dissipation energy distribution reflect the local force transmission differences.

[0066] Based on the impact boundary, the contact force and relative motion of the particle contact interface are solved to obtain the particle contact response of the test sample and the particle contact response of the reference sample.

[0067] After the particle contact interface is determined, the impact boundary is applied to the local filling model of the test sample and the local filling model of the reference sample, and the contact force and relative motion of the determined particle contact interface are solved respectively. For any particle contact interface, the normal contact force, tangential contact force, normal relative motion, and tangential relative motion are solved based on the normal approach, tangential relative displacement, and relative velocity of adjacent particles at the contact interface. The contact mechanics parameters required for the solution are determined by the material parameters of the reagent particles or the confirmed contact test parameters, and are matched with the corresponding reaction components of the particles.

[0068] As one approach, the contact force and relative motion at the particle contact interface can be solved using a particle contact model in the discrete element method. For example, the normal contact can use the Hertz contact model or the linear spring-damped model, while the tangential contact can use a tangential contact model that works in conjunction with Coulomb friction. The selection of the specific contact model does not change the way the contact dissipation work is determined.

[0069] Furthermore, the work dissipated at the particle contact interface is determined based on the contact force and the time history of relative motion. For the contact interface... During calculation time The contact dissipation work within is expressed as:

[0070]

[0071] in, For the touch interface In calculation time Contact dissipation work within, For normal damping contact force, The normal relative velocity, For tangential contact force, The tangential relative velocity, The integral time is given. For contact interfaces without tangential slip, the tangential term is taken according to the actual relative motion state of the contact interface. Thus, the particle contact responses of the test sample and the reference sample under impact boundary conditions can be obtained respectively.

[0072] Based on the contact dissipation work in the particle contact response of the test sample and the particle contact response of the reference sample, the contact dissipation energy distribution of the test sample and the contact dissipation energy distribution of the reference sample are obtained.

[0073] Based on this, the contact dissipation work in the particle contact response of the test sample is collected according to the spatial location of the particle contact interface to obtain the contact dissipation energy distribution of the test sample; the contact dissipation work in the particle contact response of the reference sample is collected according to the spatial location of the particle contact interface to obtain the contact dissipation energy distribution of the reference sample. The contact dissipation energy distribution includes the spatial location, time history and corresponding particle contact interface of the contact dissipation work, and retains the phase assignment of the reaction components of the particles on both sides of the particle contact interface.

[0074] It should be noted that contact dissipation work is not considered as a single total energy output, but rather as a spatial distribution formed by the particle contact interface. For particle contact interfaces belonging to the contact zone of the reactants, the contact dissipation work is used to convert it into a heat input process; for particle contact interfaces not belonging to the contact zone of the reactants, the contact dissipation work is used to maintain the integrity of the local energy dissipation distribution. This process establishes a correspondence between mechanical contact dissipation and the contact zone of the reactants.

[0075] In step S104, the contact dissipation energy distribution of the test sample and the contact dissipation energy distribution of the reference sample are used as the basis for heat input calculation, and the transient heat transfer response of the contact zone of the reaction components is solved in conjunction with the thermophysical property data of the reagent. The contact dissipation energy distribution of the test sample is used to calculate the hot spot temperature rise history of the test sample; the contact dissipation energy distribution of the reference sample is used to calculate the hot spot temperature rise history of the reference sample. The thermophysical property data of the reagent corresponds to the reaction components and is used to determine the heat conduction and temperature rise process in the contact zone of the reaction components and its adjacent particle regions. For the reference sample, the particle contact response, contact dissipation energy distribution, and hot spot temperature rise history are calculated according to the drop hammer input energy corresponding to the reference ignition data, so that the hot spot temperature rise history of the reference sample corresponds one-to-one with the drop hammer input energy in the reference ignition data.

[0076] The hotspot temperature rise history is used to represent the temperature rise process in the contact area of ​​the reactants under the action of impact dissipation heat input. This process uses the contact dissipation energy distribution as the heat input source and the agent's thermophysical property data as the heat transfer parameter source, so that the mechanical dissipation calculation results can be converted into the thermal response data required for ignition critical state calibration.

[0077] Specifically, the calculation of the hot spot temperature rise history of the test sample and the reference sample based on the contact dissipation energy distribution and agent thermophysical property data includes:

[0078] The contact dissipation energy distribution is converted into the heat input process of the contact zone of the reaction components;

[0079] In this conversion process, the contact zone of the reactive components is determined based on the spatial location of the particle contact interface and the phase affiliation of the reactive components in the contact dissipation energy distribution. For the test sample, the contact dissipation work belonging to the contact zone of the reactive components in the contact dissipation energy distribution of the test sample is converted into the heat input history of the contact zone of the reactive components in the test sample; for the reference sample, the contact dissipation work belonging to the contact zone of the reactive components in the contact dissipation energy distribution of the reference sample is converted into the heat input history of the contact zone of the reactive components in the reference sample.

[0080] In time increment Inside, contact interface The heat input is determined by the increment of the contact dissipation work within that time increment:

[0081]

[0082] in, For the touch interface At any moment The heat input within the corresponding time increment. For the touch interface At any moment Contact dissipation work, For the touch interface The contact dissipation work at the previous moment. The heat input history of the contact zone of the reactants can be obtained by calculating the continuous time increment.

[0083] It should be noted that when converting the contact dissipation energy distribution to the heat input history, the heat input location corresponds to the spatial location of the particle contact interface, and the heat input time corresponds to the time history of the contact dissipation work. This processing enables the hot spot temperature rise calculation to incorporate the particle contact response calculation results, avoiding the even distribution of the drop hammer input energy to the reagent layer.

[0084] The transient heat transfer response of the contact zone of the reaction components is solved based on the heat input history and the thermophysical property data of the reagent, so as to obtain the hot spot temperature rise history of the test sample and the hot spot temperature rise history of the reference sample.

[0085] After the heat input history is established, the heat input history of the contact zone between the reactants is used as the heat source term, and the thermophysical properties of the reagent are used as the heat transfer parameters to solve for the transient heat transfer responses of the test sample and the reference sample, respectively. The thermophysical properties of the reagent include the thermal conductivity, density, and specific heat capacity corresponding to the phase of the reactants. The temperature field within the contact zone between the reactants is solved according to the transient heat conduction relationship:

[0086]

[0087] in, For density, For specific heat capacity, For temperature, For time, Thermal conductivity, This refers to the volumetric or surface heat source determined by the heat input history. As one implementation, for any contact interface belonging to the contact area of ​​the reactant components, its heat input in each time increment can be converted into surface heat flux density according to the contact area of ​​the interface, or into a volumetric heat source rate according to the contact area and the equivalent heated thickness. This heat source rate is then applied to the spatial location of the contact interface according to the corresponding time increment and used as the heat source term in the above equation. Using the pre-impact agent layer temperature as the initial temperature, the solution is performed according to the spatial location of the reactant component contact area and its adjacent areas. The temperature of the outer boundary of the solution domain is treated as the pre-impact agent layer temperature to obtain the temperature change over time for each reactant component contact area.

[0088] The temperature rise history of the hot spot in the test sample is the increase in temperature of the contact area of ​​the reactants relative to the initial temperature; the temperature rise history of the hot spot in the reference sample is the increase in temperature of the contact area of ​​the reactants relative to the initial temperature. The temperature rise is expressed as:

[0089]

[0090] in, For a moment The temperature rise, For a moment temperature, The initial temperature before impact. This treatment ensures that the hotspot temperature rise history of both the test sample and the reference sample has a clearly defined source of heat input and thermophysical parameters.

[0091] In step S105, the reference ignition data is first correlated with the hot spot temperature rise history of the reference sample to determine the hot spot state corresponding to the transition from the non-ignition state to the specified ignition state under the drop hammer test conditions, which is taken as the critical ignition state. Then, the drop hammer input energy corresponding to the nominal sensitivity of the test sample is used as the starting point for reverse calculation. The drop hammer input energy is adjusted in the local filling model of the test sample, and the particle contact response, contact dissipation energy distribution and hot spot temperature rise history calculation are repeated. The drop hammer input energy corresponding to the test sample reaching the critical ignition state is used to determine the calculated impact sensitivity value of the test sample.

[0092] The ignition critical state is derived from the ignition state record of the reference sample, while the sensitivity result of the test sample is derived from the inverse calculation of its local packing model. This process can take into account both the measured ignition basis and the microscopic packing differences of the test sample.

[0093] It should be noted that this embodiment uses the measured ignition state of a reference sample with the same formulation under drop-weight test conditions to calibrate the critical ignition state, thereby replacing explicit modeling of the exothermic chemical reaction process of the reagent. Since the test sample and the reference sample have the same nominal formulation and are subjected to the same drop-weight test conditions, the contribution of the chemical reaction response to ignition is absorbed in the calibration based on the measured ignition. The calculation process characterizes the differences in mechanical dissipation and thermal response caused by differences in local packing conditions.

[0094] Specifically, the step of calibrating the critical ignition state using reference ignition data and the hot spot temperature rise history of a reference sample, and then inversely determining the starting point based on the nominal sensitivity of the sample under test, includes:

[0095] Based on the reference ignition data and the hot spot temperature rise history of the reference sample, the critical ignition state was calibrated;

[0096] During calibration, a correspondence is established between the ignition state records in the reference ignition data and the hotspot temperature rise history of the reference sample. For the same reference sample or group of reference samples, the reference ignition data is organized according to the order of the drop hammer input energy, and the drop hammer input energy range at which the ignition state changes is determined. One side of this range corresponds to not reaching the specified ignition state, and the other side corresponds to reaching the specified ignition state. The hotspot temperature rise history of the reference sample on the side of this range that reaches the specified ignition state is then used as the thermal response basis for the critical ignition state.

[0097] The ignition critical state is represented by the critical temperature rise history of the contact zone of the reactant components in the reference sample. This critical temperature rise history is derived from the correspondence between the hotspot temperature rise history of the reference sample and the reference ignition data. The maximum temperature rise in the contact zone of the reactant components during the critical temperature rise history is taken as the critical temperature rise level corresponding to the ignition critical state, and is used for comparison with the hotspot temperature rise history of the test sample. For cases where the reference ignition data includes multiple ignition state records, the hotspot temperature rise history of the reference sample corresponding to the state transition interval is selected for calibration, ensuring that the critical state corresponds to the measured ignition state. In other implementations, the ignition critical state can also be characterized by characteristic quantities such as the duration exceeding the set temperature rise level during the temperature rise history. In this case, the inverse calculation of the test sample is compared using the same characteristic quantities.

[0098] For example, the reference sample is subjected to energy input from the falling hammer. If the required ignition state is not reached, energy is input to the adjacent drop hammer. If the specified ignition state is reached, then... and The corresponding reference sample hotspot temperature rise history is correlated with the ignition state record, and the ignition critical state is determined by the hotspot temperature rise history on the side that reaches the specified ignition state. The above example is used to illustrate the calibration method of the ignition critical state, and the source of the reference ignition data and the source of the hotspot temperature rise history are not changed by this example.

[0099] Using the drop hammer input energy corresponding to the nominal sensitivity of the sample under test as the starting point for reverse calculation, the drop hammer input energy is adjusted in the local filling model of the sample under test to obtain the drop hammer input energy that reaches the ignition critical state.

[0100] Specifically, the nominal sensitivity of the sample to be tested is first converted into the drop weight input energy, and this drop weight input energy is used as the starting point for reverse calculation. If the nominal sensitivity of the sample to be tested is the characteristic drop height... Then, the energy input of the falling hammer corresponding to the starting point is expressed as: ;

[0101] in, To inversely calculate the input energy of the falling hammer corresponding to the starting point, For the falling weight, It is the acceleration due to gravity. This represents the characteristic drop height corresponding to the nominal sensitivity of the sample under test.

[0102] by As the initial drop hammer input energy, the particle contact response is solved in the localized loading model of the sample under test to obtain the corresponding contact dissipation energy distribution of the sample under test, and the hot spot temperature rise history of the sample under test is further calculated. The hot spot temperature rise history of the sample under test is compared with the calibrated ignition critical state. The comparison is made by comparing the maximum temperature rise of the contact zone of the reactants in the hot spot temperature rise history of the sample under test with the critical temperature rise level. If the hot spot temperature rise history of the sample under test does not reach the ignition critical state, the drop hammer input energy is increased and the calculation is repeated; if the hot spot temperature rise history of the sample under test exceeds the ignition critical state, the drop hammer input energy is decreased and the calculation is repeated. Through continuous adjustment, the hot spot temperature rise history of the sample under test is brought to the ignition critical state, and the corresponding drop hammer input energy is obtained.

[0103] To ensure the determinism of the inverse calculation process, an energy range convergence method is used for adjustment. Starting with the inverse calculation point as the initial energy, the energy endpoints before and after reaching the ignition critical state are determined. The calculation range is then gradually narrowed within this energy range until the difference between two consecutive calculated drop hammer input energies meets the numerical accuracy determined by the drop hammer test resolution. The drop hammer input energy at this point is taken as the drop hammer input energy required for the sample to reach the ignition critical state. This adjustment process is always performed within the locally packed model of the sample under test.

[0104] The calculated impact sensitivity value of the sample under test is obtained based on the energy input of the falling hammer when it reaches the critical ignition state.

[0105] After the reverse calculation is completed, the drop hammer input energy required for the test sample to reach the ignition critical state is converted into a characteristic drop height to obtain the calculated impact sensitivity value of the test sample. If the drop hammer input energy required for the test sample to reach the ignition critical state is... The calculated impact sensitivity value of the sample to be tested is expressed as: ;

[0106] in, The impact sensitivity value of the sample to be tested is calculated. Energy is input to the drop hammer to bring the sample to the critical ignition state. For the falling weight, This represents gravitational acceleration. Through this conversion, the resulting energy is transformed into a characteristic drop height corresponding to the impact sensitivity characterization method of the falling hammer.

[0107] The calculated impact sensitivity value of the test sample is derived from the drop hammer input energy required to reach the ignition critical state in the local loading model of the test sample. This calculation process uses reference ignition data and the hot spot temperature rise history of the reference sample as the calibration basis for the ignition critical state, and combines the spatial state of the agent particles, the distribution of contact dissipation energy, and the hot spot temperature rise history within the load range of the test sample to determine the calculated impact sensitivity value, so that the calculation results can reflect the difference in impact response caused by the difference in local loading state of samples with the same formulation.

[0108] Example 2

[0109] Please see Figure 2 As shown, this embodiment discloses an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements any of the above-described methods for calculating the impact sensitivity of fireworks and firecracker agents.

[0110] Since the electronic device described in this embodiment is the electronic device used to implement the method for calculating the impact sensitivity of fireworks and firecrackers in this embodiment of the invention, those skilled in the art can understand the specific implementation and various variations of the electronic device in this embodiment based on the method for calculating the impact sensitivity of fireworks and firecrackers described in this embodiment of the invention. Therefore, how the electronic device implements the method in this embodiment of the invention will not be described in detail here. Any electronic device used by those skilled in the art to implement the method for calculating the impact sensitivity of fireworks and firecrackers in this embodiment of the invention falls within the scope of protection of this invention.

[0111] Example 3

[0112] Please see Figure 3 As shown, this embodiment discloses a computer-readable storage medium storing a computer program, which, when executed by a processor, implements any of the above-described methods for calculating the impact sensitivity of fireworks and firecracker agents.

[0113] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, as a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, all or part of the processes or functions described in the embodiments of the present invention are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via a wired or wireless network. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more sets of available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. A semiconductor medium can be a solid-state drive.

[0114] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed in this invention can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0115] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0116] In the several embodiments provided by this invention, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0117] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0118] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0119] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

[0120] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for calculating the impact sensitivity of fireworks and firecracker agents, characterized in that, include: Obtain detailed characterization data of the sample to be tested and the reference sample with the same formulation, and read the drop hammer test conditions, reference ignition data, agent thermophysical property data and the nominal sensitivity of the sample to be tested; The impact boundary is determined according to the drop hammer test conditions, and the local filling models of the test sample and the reference sample are reconstructed respectively. This includes: mapping the drop hammer test conditions to the microscopic characterization data of the test sample and the reference sample with the same formulation to obtain the load range of the test sample and the load range of the reference sample; and reconstructing the local filling models of the test sample and the reference sample respectively based on the spatial state of the drug particles within the load range of the test sample and the load range of the reference sample. The particle contact response of the test sample's local filling model and the reference sample's local filling model are solved under the impact boundary to obtain the corresponding contact dissipation energy distribution. This includes: aggregating the contact dissipation energy in the particle contact response of the test sample according to the spatial position of the particle contact interface to obtain the contact dissipation energy distribution of the test sample; aggregating the contact dissipation energy in the particle contact response of the reference sample according to the spatial position of the particle contact interface to obtain the contact dissipation energy distribution of the reference sample; the contact dissipation energy distribution includes the spatial position, time history and corresponding particle contact interface of the contact dissipation energy, and retains the phase attribution of the reaction components of the particles on both sides of the particle contact interface. Based on the contact dissipation energy distribution and reagent thermophysical property data, the hot spot temperature rise history of the test sample and the hot spot temperature rise history of the reference sample are calculated respectively. This includes: converting the contact dissipation energy distribution into the heat input history of the contact area of ​​the reaction components; solving the transient heat transfer response of the contact area of ​​the reaction components based on the heat input history and reagent thermophysical property data to obtain the hot spot temperature rise history of the test sample and the hot spot temperature rise history of the reference sample; wherein, for the reference sample, the particle contact response, contact dissipation energy distribution and hot spot temperature rise history are calculated according to the drop hammer input energy corresponding to the reference ignition data, so that the hot spot temperature rise history of the reference sample corresponds one-to-one with the drop hammer input energy in the reference ignition data. The critical ignition state is calibrated using reference ignition data and the hotspot temperature rise history of a reference sample. The starting point is then determined by inversely calculating the impact sensitivity value of the sample under test, based on the nominal sensitivity limit of the sample under test. This includes: Based on reference ignition data and the hotspot temperature rise history of reference samples, the critical ignition state is calibrated. This includes: for the same reference sample or group of reference samples, organizing the reference ignition data according to the order of the drop hammer input energy, and determining the drop hammer input energy range where the ignition state changes. One side of this range corresponds to not reaching the specified ignition state, and the other side corresponds to reaching the specified ignition state. The hotspot temperature rise history of the reference sample on the side of the range that reaches the specified ignition state is used as the thermal response basis for the critical ignition state. Using the drop hammer input energy corresponding to the nominal sensitivity of the sample under test as the starting point for inverse calculation, the drop hammer input energy is adjusted in the local filling model of the sample under test to obtain the drop hammer input energy that reaches the ignition critical state. This includes: adjusting using an energy range convergence method, using the starting point for inverse calculation as the initial energy, determining the energy endpoints that have not reached the ignition critical state and the energy endpoints that have reached the ignition critical state, and then gradually narrowing the calculation range within this energy range until the difference between the drop hammer input energies obtained from two adjacent calculations meets the numerical accuracy determined by the drop hammer test resolution. The drop hammer input energy corresponding to this point is taken as the drop hammer input energy that the sample under test reaches the ignition critical state. The calculated impact sensitivity value of the sample under test is obtained based on the energy input of the falling hammer when it reaches the critical ignition state.

2. The calculation method according to claim 1, characterized in that, The microscopic characterization data are three-dimensional characterization data that can characterize the spatial state of the drug particles and distinguish the phase affiliation of the reaction components. The reference ignition data are the ignition state records of the reference sample with the same formulation under the drop hammer test conditions. The nominal sensitivity of the test sample is the characteristic drop height of the nominal formulation corresponding to the test sample.

3. The calculation method according to claim 1, characterized in that, The microstructure data mapping the drop weight test conditions to the test sample and the reference sample with the same formulation includes: The impact area of ​​the test sample and the impact area of ​​the reference sample are determined based on the contact projection between the drop hammer head and the surface of the reagent layer. By extending the impact area of ​​the test sample and the impact area of ​​the reference sample along the direction of the falling hammer load transmission, the load range of the test sample and the load range of the reference sample are obtained.

4. The calculation method according to claim 1, characterized in that, The step of solving the particle contact response of the local packing model of the test sample and the local packing model of the reference sample under the impact boundary includes: The particle contact interface involved in impact force transmission is determined in the local loading model of the sample to be tested and the local loading model of the reference sample. Based on the impact boundary, the contact force and relative motion of the particle contact interface are solved to obtain the particle contact response of the test sample and the particle contact response of the reference sample.

5. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method according to any one of claims 1 to 4.

6. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method described in any one of claims 1 to 4.

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