Method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic material

Abstract

The invention provides a method for calibrating contact parameters of micron-sized spherical aluminum powder for an energetic material, and the basic principle of the method is that discrete element simulation and experiment are combined, errors of a simulation repose angle and an experiment repose angle are compared, different calibration sequences are adopted for different errors, and the contact parameters of micron-sized spherical aluminum powder for the energetic material are calibrated. And gradually completing the contact parameter calibration of the micron-sized spherical aluminum powder for the energetic material. According to the method, it is proposed for the first time that for micron-sized spherical aluminum powder, four contact parameters including the collision recovery coefficient, the sliding friction coefficient, the rolling friction coefficient and the adsorption energy among particles need to be calibrated, and the proper coarsening range of the aluminum powder during modeling, the calibration sequence under different conditions and the contact parameter calibration range are defined for the first time; according to the method, the contact parameter calibration workload of the micron-sized spherical aluminum powder is reduced, and efficient preparation of the energetic material is promoted.

Description

Technical Field

[0001] The invention belongs to the technical field of energetic material manufacturing, relates to parameter calibration of raw materials, and specifically relates to a calibration method for contact parameters of micron-grade spherical aluminum powder for energetic materials. Background Art

[0002] For the vast majority of energetic materials, micron-sized spherical aluminum powder is the core component, and its uniform distribution at the microscopic level is of great significance for the efficient and safe preparation of energetic materials. In the preparation process of energetic materials, it is difficult to observe the distribution of aluminum powder in real time with existing detection methods. It is necessary to rely on simulation methods to analyze the movement law of aluminum powder, and then guide the actual preparation process parameter control. In order to accurately predict the movement of micron-sized spherical aluminum powder, its contact parameters need to be clarified. Since there are many variables that affect the fluidity of micron-sized spherical aluminum powder at the microscopic level, the calibration is difficult and the workload is large. It is necessary to propose a contact parameter calibration method for micron-sized spherical aluminum powder suitable for energetic materials to guide the rapid and accurate calibration of its contact parameters and provide support for the efficient preparation of energetic materials. Summary of the invention

[0003] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method for calibrating the contact parameters of micron-sized spherical aluminum powder for energetic materials, so as to solve the technical problems in the prior art of calibrating the contact parameters of micron-sized spherical aluminum powder for energetic materials, such as large number of fluidity variables, high calibration difficulty and large workload.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions to achieve the above problems:

[0005] A method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic materials, the method specifically comprising the following steps:

[0006] Step 1: Take micron-sized spherical aluminum powder and conduct an angle of repose experiment to obtain the experimental angle of repose of the micron-sized spherical aluminum powder.

[0007] Step 2: Based on the discrete element method, a simulation geometric model of the repose angle of micron-sized spherical aluminum powder is established.

[0008] Step 3: Clarify the calibration order:

[0009] The values ​​of the contact parameters of micron-sized spherical aluminum powder are set to carry out the simulation of the angle of repose; the contact parameters of the micron-sized spherical aluminum powder include the collision recovery coefficient, rolling friction coefficient, sliding friction coefficient and adsorption energy between micron-sized spherical aluminum powder particles.

[0010] If the error between the obtained simulated repose angle and the experimental repose angle obtained in step 1 is greater than 30%, the calibration order is determined as: adsorption energy calibration, collision recovery coefficient calibration, rolling friction coefficient calibration, sliding friction coefficient calibration.

[0011] If the error between the obtained simulated repose angle and the experimental repose angle obtained in step 1 is less than or equal to 30%, the calibration order is determined as: collision recovery coefficient calibration, adsorption energy calibration, rolling friction coefficient calibration, sliding friction coefficient calibration.

[0012] Step 4: Calibrate contact parameters:

[0013] According to the order determined in step three, the repose angle simulation work is carried out to obtain the calibration values ​​of the contact parameters of micron-sized spherical aluminum powder.

[0014] Step five, integrating the calibration values ​​of the contact parameters obtained in step four, thus completing the calibration of the contact parameters of the micron-sized spherical aluminum powder for energetic materials.

[0015] The present invention also has the following technical features:

[0016] Specifically and preferably, in step 2, during modeling, the coarsening multiple of the particle size of the micron-sized spherical aluminum powder is 3 to 10 times.

[0017] Specifically and optionally, the step 4 includes the following steps:

[0018] Step 4.1, obtain the adsorption energy calibration value:

[0019] The collision recovery coefficient between micron-sized spherical aluminum powder particles is set to e, e=0.5; the rolling friction coefficient is set to δ, δ=0.5; and the sliding friction coefficient is set to μ, μ=0.5.

[0020] Starting from the initial value of adsorption energy Eads0, Eads0 = 0.0005 J / m 3 , gradually increase the adsorption energy value with the adjustment interval of ΔEads, and carry out a series of simulation work on the angle of repose, 0.0001J / m 3 ≤ΔEads≤0.0005J / m 3 ; Record the simulated repose angle obtained at each adsorption energy until the adsorption energy is assigned to 0.005 J / m 3 Stop the simulation.

[0021] If the errors between all simulated angles of repose and the experimental angles of repose are greater than 0.5%, and no serious particle agglomeration is observed during the simulation, select a simulation in which the simulated angle of repose is closest to the experimental angle of repose, and then set the adsorption energy corresponding to this simulation as the adsorption energy calibration value, and proceed to step 4.2.

[0022] If the errors between all simulated angles of repose and the experimental angles of repose are greater than 0.5%, but serious particle agglomeration occurs during the simulation in which the simulated angle of repose is closest to the experimental angle of repose, select the simulation in which the simulated angle of repose is closest to the experimental angle of repose and no serious particle agglomeration occurs, then set the adsorption energy value corresponding to this simulation as the adsorption energy calibration value and proceed to step 4.2.

[0023] If the error between a simulated repose angle and an experimental repose angle is less than or equal to 0.5%, the adsorption energy value corresponding to this simulation is set to the adsorption energy calibration value, the collision recovery coefficient calibration value is e, the rolling friction coefficient calibration value is δ, the sliding friction coefficient calibration value is μ, and proceed directly to step five.

[0024] Step 4.2, obtain the collision recovery coefficient calibration value:

[0025] The adsorption energy between micron-sized spherical aluminum powder particles is set to the adsorption energy calibration value obtained in step 4.1; the rolling friction coefficient is set to δ, δ = 0.5; and the sliding friction coefficient is set to μ, μ = 0.5.

[0026] Starting with the initial value e0 of the collision recovery coefficient, e0=0.5, gradually increase or decrease the assigned value of the collision recovery coefficient with an adjustment interval of Δe in the range of [0.4, 0.7], and carry out a series of repose angle simulations, 0.01≤Δe≤0.02; record the simulated repose angle obtained under each collision recovery coefficient, and stop the simulation until the assigned value of the collision recovery coefficient is 0.4 or 0.7.

[0027] If the errors between all simulated repose angles and experimental repose angles are greater than 0.5%, select a simulation in which the simulated repose angle is closest to the experimental repose angle, then set the value of the collision restitution coefficient corresponding to this simulation as the collision restitution coefficient calibration value, and proceed to step 4.3.

[0028] If the error between a simulated repose angle and an experimental repose angle is less than or equal to 0.5%, the collision recovery coefficient value corresponding to this simulation is set as the collision recovery coefficient calibration value, the rolling friction coefficient calibration value is δ, the sliding friction coefficient calibration value is μ, and step five is directly performed.

[0029] Step 4.3, obtain the rolling friction coefficient calibration value:

[0030] The adsorption energy between micron-sized spherical aluminum powder particles is set to the adsorption energy calibration value obtained in step 4.1; the collision recovery coefficient is set to the collision recovery coefficient calibration value obtained in step 4.2; and the sliding friction coefficient is set to μ.

[0031] Starting with the initial value δ0 of the rolling friction coefficient, δ0=0.5, if the simulated repose angle finally obtained in step 4.2 is greater than the experimental repose angle, then gradually reduce the assigned value of the rolling friction coefficient by an adjustment interval of Δδ in the range of [0.3, 0.5], and carry out a series of repose angle simulations, 0.01≤Δδ≤0.03; record the simulated repose angle obtained under each rolling friction coefficient, and stop the simulation until the assigned value of the rolling friction coefficient is 0.3.

[0032] If the simulated repose angle finally obtained in step 4.2 is smaller than the experimental repose angle, gradually increase the assigned value of the rolling friction coefficient with an adjustment interval of Δδ in the range of [0.5, 0.6], and carry out a series of repose angle simulations, 0.01≤Δδ≤0.03; record the simulated repose angle obtained under each rolling friction coefficient, and stop the simulation when the assigned value of the rolling friction coefficient is 0.6.

[0033] If the errors between all simulated repose angles and experimental repose angles are greater than 0.5%, select a simulation in which the simulated repose angle is closest to the experimental repose angle, then set the value of the rolling friction coefficient corresponding to this simulation as the rolling friction coefficient calibration value, and proceed to step 4.4.

[0034] If the error between a simulated repose angle and an experimental repose angle is less than or equal to 0.5%, the rolling friction coefficient value corresponding to this simulation is set as the rolling friction coefficient calibration value, the sliding friction coefficient calibration value is μ, and step five is directly performed.

[0035] Step 4.4, obtain the calibration value of sliding friction coefficient:

[0036] The adsorption energy between micron-sized spherical aluminum powder particles is set to the adsorption energy calibration value obtained in step 4.1; the collision recovery coefficient is set to the collision recovery coefficient calibration value obtained in step 4.2; and the rolling friction coefficient is set to the rolling friction coefficient calibration value obtained in step 4.3.

[0037] Starting with the initial value μ0 of the sliding friction coefficient, μ0=0.5, if the simulated repose angle finally obtained in step 4.3 is greater than the experimental repose angle, then gradually reduce the assigned value of the sliding friction coefficient by an adjustment interval of Δμ in the range of [0.4, 0.5], and carry out a series of repose angle simulations, 0.02≤Δμ≤0.04; record the simulated repose angle obtained under each sliding friction coefficient, and stop the simulation until the assigned value of the sliding friction coefficient is 0.4.

[0038] If the simulated repose angle finally obtained in step 4.3 is smaller than the experimental repose angle, then gradually increase the assigned value of the sliding friction coefficient with an adjustment interval of Δμ in the range of [0.5, 0.8], and carry out a series of repose angle simulations, 0.02≤Δμ≤0.04; record the simulated repose angle obtained under each sliding friction coefficient, and stop the simulation until the assigned value of the sliding friction coefficient is 0.8.

[0039] Select a simulation in which the simulated repose angle is closest to the experimental repose angle, then set the value of the sliding friction coefficient corresponding to this simulation as the sliding friction coefficient calibration value, and proceed to step five.

[0040] Specifically and optionally, the step 4 includes the following steps:

[0041] Step 4.1, obtain the collision restitution coefficient calibration value:

[0042] The adsorption energy between micron-sized spherical aluminum powder particles is set to Eads, Eads = 0.0005 J / m 3 ; Set the rolling friction coefficient to δ, δ=0.5; set the sliding friction coefficient to μ, μ=0.5.

[0043] Starting with the initial value e0 of the collision recovery coefficient, e0=0.5, gradually increase or decrease the assigned value of the collision recovery coefficient with an adjustment interval of Δe in the range of [0.4, 0.7], and carry out a series of repose angle simulations, 0.01≤Δe≤0.02; record the simulated repose angle obtained under each collision recovery coefficient, and stop the simulation until the assigned value of the collision recovery coefficient is 0.4 or 0.7.

[0044] If the errors between all simulated repose angles and experimental repose angles are greater than 0.5%, select a simulation in which the simulated repose angle is closest to the experimental repose angle, then set the value of the collision restitution coefficient corresponding to this simulation as the collision restitution coefficient calibration value, and proceed to step 4.2.

[0045] If the error between a simulated repose angle and an experimental repose angle is less than or equal to 0.5%, the collision recovery coefficient corresponding to this simulation is set to the collision recovery coefficient calibration value, the rolling friction coefficient calibration value is δ, the sliding friction coefficient calibration value is μ, the adsorption energy calibration value is Eads, and proceed directly to step five.

[0046] Step 4.2, obtain the adsorption energy calibration value:

[0047] The collision recovery coefficient between micron-sized spherical aluminum powder particles is set to the collision recovery coefficient calibration value obtained in step 4.1; the rolling friction coefficient is set to δ, δ = 0.5; and the sliding friction coefficient is set to μ, μ = 0.5.

[0048] Starting from the initial value of adsorption energy Eads0, Eads0 = 0.0005 J / m 3 , gradually increase the adsorption energy value with the adjustment interval of ΔEads, and carry out a series of simulation work on the angle of repose, 0.0001J / m 3 ≤ΔEads≤0.0005J / m 3 ; Record the simulated repose angle obtained at each adsorption energy until the adsorption energy is assigned to 0.005 J / m 3 Stop the simulation.

[0049] If the errors between all simulated angles of repose and the experimental angles of repose are greater than 0.5%, and no serious particle agglomeration is observed during the simulation, select a simulation in which the simulated angle of repose is closest to the experimental angle of repose, and then set the adsorption energy corresponding to this simulation as the adsorption energy calibration value, and proceed to step 4.3.

[0050] If the errors between all simulated angles of repose and the experimental angles of repose are greater than 0.5%, but serious particle agglomeration occurred during the simulation in which the simulated angle of repose is closest to the experimental angle of repose, select the simulation in which the simulated angle of repose is closest to the experimental angle of repose and no serious particle agglomeration occurred, then set the adsorption energy value corresponding to this simulation as the adsorption energy calibration value and proceed to step 4.3.

[0051] If the error between a simulated repose angle and an experimental repose angle is less than or equal to 0.5%, the adsorption energy value corresponding to this simulation is set as the adsorption energy calibration value, the rolling friction coefficient calibration value is δ, the sliding friction coefficient calibration value is μ, and step five is directly performed.

[0052] Step 4.3, obtain the rolling friction coefficient calibration value:

[0053] The collision recovery coefficient between micron-sized spherical aluminum powder particles is set to the collision recovery coefficient calibration value obtained in step 4.1; the adsorption energy is set to the adsorption energy calibration value obtained in step 4.2; and the sliding friction coefficient is set to μ.

[0054] Starting with the initial value δ0 of the rolling friction coefficient, δ0=0.5, if the simulated repose angle finally obtained in step 4.2 is greater than the experimental repose angle, then gradually reduce the assigned value of the rolling friction coefficient by an adjustment interval of Δδ in the range of [0.3, 0.5], and carry out a series of repose angle simulations, 0.01≤Δδ≤0.03; record the simulated repose angle obtained under each rolling friction coefficient, and stop the simulation until the assigned value of the rolling friction coefficient is 0.3.

[0055] If the simulated repose angle finally obtained in step 4.2 is smaller than the experimental repose angle, then gradually increase the assigned value of the rolling friction coefficient within the range of [0.5, 0.6] with an adjustment interval of Δδ, and carry out a series of repose angle simulations, 0.01≤Δδ≤0.03, and record the simulated repose angle obtained under each rolling friction coefficient until the simulation is stopped when the assigned value of the rolling friction coefficient is 0.6.

[0056] If the errors between all simulated repose angles and experimental repose angles are greater than 0.5%, select a simulation in which the simulated repose angle is closest to the experimental repose angle, then set the value of the rolling friction coefficient corresponding to this simulation as the rolling friction coefficient calibration value, and proceed to step 4.4.

[0057] If the error between a simulated repose angle and an experimental repose angle is less than or equal to 0.5%, the rolling friction coefficient value corresponding to this simulation is set as the rolling friction coefficient calibration value, the sliding friction coefficient calibration value is μ, and step five is directly performed.

[0058] Step 4.4, obtain the calibration value of sliding friction coefficient:

[0059] The collision recovery coefficient between micron-sized spherical aluminum powder particles is set to the collision recovery coefficient calibration value obtained in step 4.1; the adsorption energy is set to the adsorption energy calibration value obtained in step 4.2; and the rolling friction coefficient is set to the rolling friction coefficient calibration value obtained in step 4.3.

[0060] Starting with the initial value μ0 of the sliding friction coefficient, μ0=0.5, if the simulated repose angle finally obtained in step 4.3 is greater than the experimental repose angle, then gradually reduce the assigned value of the sliding friction coefficient by an adjustment interval of Δμ in the range of [0.4, 0.5], and carry out a series of repose angle simulations, 0.02≤Δμ≤0.04; record the simulated repose angle obtained under each sliding friction coefficient, and stop the simulation until the assigned value of the sliding friction coefficient is 0.4.

[0061] If the simulated repose angle finally obtained in step 4.3 is smaller than the experimental repose angle, then gradually increase the assigned value of the sliding friction coefficient with an adjustment interval of Δμ in the range of [0.5, 0.8], and carry out a series of repose angle simulations, 0.02≤Δμ≤0.04; record the simulated repose angle obtained under each sliding friction coefficient, and stop the simulation until the assigned value of the sliding friction coefficient is 0.8.

[0062] Select a simulation in which the simulated repose angle is closest to the experimental repose angle, then set the value of the sliding friction coefficient corresponding to this simulation as the sliding friction coefficient calibration value, and proceed to step five.

[0063] Specifically and preferably, the diameter of the micron-sized spherical aluminum powder is 13 microns to 35 microns.

[0064] Specifically, the step one comprises: weighing multiple groups of micron-sized spherical aluminum powders of different masses; repeating the angle of repose experiment for each group of micron-sized spherical aluminum powders for several times to obtain multiple angle of repose values; calculating and obtaining the average experimental angle of repose α of the multiple groups of micron-sized spherical aluminum powders of different masses, and the average experimental angle of repose α is the experimental angle of repose of the aluminum powder.

[0065] Specifically and preferably, in step 1, the repose angle experiment is repeated 3 to 10 times for each group of micron-sized spherical aluminum powders.

[0066] Specifically and preferably, in step 1, the mass range of each group of micron-sized spherical aluminum powder is 10 g to 100 g, and the average mass of multiple groups of micron-sized spherical aluminum powders of different masses is W1.

[0067] Specifically, in step 2, the modeling process includes: setting the micron-sized spherical aluminum powder particles and the particle model as the JKR model, generating W1 grams of micron-sized spherical aluminum powder particles in the simulation model, and obtaining the repose angle simulation geometric model of the aluminum powder.

[0068] Specifically, in step 3, the collision recovery coefficient between micron-sized spherical aluminum powder particles is set to e1, e1 = 0.5; the rolling friction coefficient is set to δ1, δ1 = 0.5; the sliding friction coefficient is set to μ1, μ1 = 0.5; the adsorption energy is set to Eads1, Eads1 = 0.0005 J / m 3 .

[0069] The beneficial technical effects of the present invention compared with the prior art are as follows:

[0070] (I) The present invention proposes for the first time that, for micron-sized spherical aluminum powder, it is necessary to calibrate the four contact parameters of inter-particle collision recovery coefficient, sliding friction coefficient, rolling friction coefficient and adsorption energy. Among them, the collision recovery coefficient between micron-sized spherical aluminum powder particles reflects the particle collision type, and the sliding friction coefficient and rolling friction coefficient represent the fluidity of the particles. In addition, due to the small particle size of micron-sized spherical aluminum powder, the surface adsorption between particles is large and it is easy to agglomerate during the preparation process, so the adsorption energy between micron-sized spherical aluminum powder particles also needs to be considered.

[0071] (II) Based on the above four contact parameters, the present invention proposes for the first time a contact parameter calibration method for micron-sized spherical aluminum powder for energetic material manufacturing combined with discrete element simulation, and clarifies the appropriate coarsening range of aluminum powder during modeling, the calibration order under different conditions, and the contact parameter calibration range. The repose angle is obtained through the repose angle experiment, and the contact parameters of the micron-sized spherical aluminum powder are further calibrated by means of discrete element simulation, completing the calibration of the contact parameters of the micron-sized spherical aluminum powder suitable for energetic material manufacturing, reducing the workload of the calibration of the contact parameters of the micron-sized spherical aluminum powder, and promoting the efficient preparation of energetic materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1 Schematic diagram of the flow chart of the calibration method of contact parameters of micron-sized spherical aluminum powder for energetic materials.

[0073] The technical solution of the present invention is further described below in conjunction with embodiments. DETAILED DESCRIPTION

[0074] It should be noted that all experimental methods, models and simulation software used in the present invention, unless otherwise specified, are experimental methods, models and simulation software known in the art. For example:

[0075] The angle of repose test refers to the conventional angle of repose test method known in the prior art and refers to the Chinese national standard GB / T 16913.5-1997.

[0076] The establishment of the repose angle simulation geometric model and the repose angle simulation work all use the EDEM software (multi-purpose discrete element method modeling software) known in the prior art. Unless otherwise specified, the parameters used are all software default parameters.

[0077] Discrete Element Method (DEM) is a conventional modeling method known in the prior art, and its basic principle is to model the dynamic mechanical properties of particles by numerical methods.

[0078] The JKR model is a conventional theoretical model known in the prior art. Specifically, the JKR model is a theoretical model for describing the adhesion between solid materials. It describes the adhesion between two solid surfaces, especially the elastic deformation region in the contact area.

[0079] In accordance with the above technical scheme, specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent changes made on the basis of the technical scheme of this application fall within the protection scope of the present invention.

[0080] Embodiment 1:

[0081] This embodiment provides a method for calibrating the contact parameters of micron-sized spherical aluminum powder for energetic materials. The basic principle of this method is to combine discrete element simulation and experiment, compare the error of the simulated repose angle and the experimental repose angle, adopt different calibration orders for different errors, and gradually complete the calibration of the contact parameters of micron-sized spherical aluminum powder for energetic materials. Figure 1 As shown, the method specifically comprises the following steps:

[0082] Step 1, take 13-micron spherical aluminum powder particles and conduct an angle of repose experiment to obtain the experimental angle of repose of the aluminum powder: weigh 10g, 20g, and 30g of micron-grade spherical aluminum powder with a diameter of 13 microns, respectively, and conduct angle of repose experiments, repeat 6 times at each mass, and obtain a total of 18 angle of repose values; in this embodiment, after calculation, it can be obtained that the average mass of the three groups of aluminum powder is 20g, and the average experimental angle of repose is 74.5°, which is the experimental angle of repose of the aluminum powder.

[0083] Step 2: Establish a simulation geometric model of the angle of repose of micron-sized spherical aluminum powder based on the discrete element method. The modeling process includes: coarsening the aluminum powder particle size by 10 times (i.e., setting the aluminum powder particle size to 130 microns), setting the micron-sized spherical aluminum powder particles and the particle model to the JKR model, generating 20 g of 13-micron spherical aluminum powder particles in the simulation model, and obtaining the simulation geometric model of the angle of repose of aluminum powder.

[0084] Step 3: Clarify the calibration order:

[0085] The collision recovery coefficient between 13-micron spherical aluminum powder particles was set to 0.5, the rolling friction coefficient was set to 0.5, the sliding friction coefficient was set to 0.5, and the adsorption energy was set to 0.0005 J / m 3 , carried out the simulation work of the repose angle of 13-micron spherical aluminum powder.

[0086] In this embodiment, the obtained simulated repose angle is 45.27°, and the error with the experimental repose angle is 39.23°, which is greater than 30%. Therefore, the contact parameters are calibrated in the order of adsorption energy, collision recovery coefficient, rolling friction coefficient, and sliding friction coefficient (as shown in steps 4.1 to 4.4 below) until the error between the simulated repose angle and the experimental repose angle is less than or equal to 0.5%.

[0087] Step 4: Calibrate contact parameters:

[0088] Step 4.1, obtain the adsorption energy calibration value:

[0089] The collision recovery coefficient between 13-micron spherical aluminum powder particles was set to 0.5, the rolling friction coefficient was set to 0.5, and the sliding friction coefficient was set to 0.5; the initial value of adsorption energy was 0.0005 J / m 3 Starting from 0.0005 J / m 3 The adsorption energy value was gradually increased by adjusting the interval, and a series of repose angle simulations were carried out. The simulated repose angle obtained under each adsorption energy was recorded until the adsorption energy value was 0.005 J / m 3 Stop the simulation.

[0090] A simulation in which the simulated angle of repose is closest to the experimental angle of repose is selected, and then the value of the collision restitution coefficient corresponding to this simulation is set as the collision restitution coefficient calibration value; if serious particle agglomeration occurs during the simulation in which the simulated angle of repose is closest to the experimental angle of repose, a simulation in which the simulated angle of repose is closest to the experimental angle of repose and no serious particle agglomeration occurs is selected, and then the adsorption energy value corresponding to this simulation is set as the adsorption energy calibration value.

[0091] In this embodiment, the simulated repose angle results obtained under each adsorption energy are shown in Table 1:

[0092] Table 1. Simulated repose angles obtained with different adsorption energies

[0093] <![CDATA[Adsorption energy / J m 3 > Simulated repose angle / ° <![CDATA[Adsorption energy / J m 3 > Simulated repose angle / ° 0.0005 45.27 0.0035 75.4 0.001 50.35 0.004 76.75 0.0015 54.98 0.0045 78.3 0.002 60.15 0.005 80.11 0.0025 65.77 0.003 70.31

[0094] It can be seen from Table 1 that when the adsorption energy is assigned to 0.0035 J / m 3 When the adsorption energy is greater than 0.003 J / m 3 When the particle size was 0.0005 × 100 nm, the particle aggregation phenomenon was observed in the simulation, which was inconsistent with the actual experimental phenomenon. Therefore, the adsorption energy value of 0.003 J / m was selected, which was close to the experimental phenomenon and the closest to the experimental repose angle. 3 At this time, the simulated repose angle is 70.31°, and the error with the experimental repose angle is 5.6%. 0.003J / m 3 The adsorption capacity can be used to carry out the next calibration work.

[0095] Step 4.2, collision restitution coefficient calibration:

[0096] The adsorption energy between 13-micron spherical aluminum powder particles is set to 0.003 J / m 3 , the rolling friction coefficient is set to 0.5, and the sliding friction coefficient is set to 0.5; starting with the initial value of the collision recovery coefficient of 0.5, in the range of [0.4, 0.7], the collision recovery coefficient is gradually increased and decreased with an adjustment interval of 0.01, and a series of repose angle simulations are carried out, and the simulated repose angle obtained under each collision recovery coefficient is recorded until the collision recovery coefficient is assigned to 0.4 and 0.7. The simulation is selected when the simulated repose angle is closest to the experimental repose angle, and then the collision recovery coefficient corresponding to this simulation is set as the collision recovery coefficient calibration value.

[0097] In this embodiment, when the collision recovery coefficient is assigned a value of 0.54, the simulated repose angle of 13-micron spherical aluminum powder reaches a maximum value of 72.19°, which is closest to the experimental repose angle with an error of 3.1%. The collision recovery coefficient of 0.54 is selected to carry out the next calibration work.

[0098] Step 4.3, obtain the rolling friction coefficient calibration value:

[0099] The adsorption energy between 13-micron spherical aluminum powder particles is set to 0.003 J / m 3 , the collision recovery coefficient is set to 0.54, and the sliding friction coefficient is set to 0.5; the simulated repose angle obtained in step 4.2 is 72.19°, which is less than the experimental repose angle of 74.5°. Starting with the initial value of the rolling friction coefficient of 0.5, the assigned value of the rolling friction coefficient is gradually increased with an adjustment interval of 0.01, and a series of repose angle simulations are carried out. The simulated repose angle obtained under each rolling friction coefficient is recorded until the assigned value of the rolling friction coefficient is 0.6 and the simulation is stopped. Select a simulation with the simulated repose angle closest to the experimental repose angle, and then set the assigned value of the rolling friction coefficient corresponding to this simulation as the rolling friction coefficient calibration value.

[0100] In this embodiment, when the rolling friction coefficient is assigned a value of 0.58, the simulated repose angle is 74.1°, which is closest to the experimental repose angle with an error of 0.54%. The rolling friction coefficient of 0.58 is selected to carry out the next calibration work.

[0101] Step 4.4, sliding friction coefficient calibration:

[0102] The adsorption energy between 13-micron spherical aluminum powder particles is set to 0.003 J / m 3 , the collision recovery coefficient is set to 0.54, and the rolling friction coefficient is set to 0.58; the simulated repose angle obtained in step 4.3 is 74.1°, which is smaller than the experimental repose angle of 74.5°. Starting with the initial value of the sliding friction coefficient of 0.5, the sliding friction coefficient is gradually increased with an adjustment interval of 0.02, and a series of repose angle simulations are carried out. The simulated repose angle obtained under each sliding friction coefficient is recorded until the sliding friction coefficient is assigned to 0.8 and the simulation is stopped. Select the simulation with the simulated repose angle closest to the experimental repose angle, and then set the assigned sliding friction coefficient corresponding to this simulation as the sliding friction coefficient calibration value.

[0103] In this embodiment, when the sliding friction coefficient is assigned a value of 0.64, the simulated repose angle is 74.65°, which is closest to the experimental repose angle, with an error of 0.2%, which is less than 0.5%, and the calibration is completed.

[0104] Step five, combining the adsorption energy calibration value obtained in step 4.1, the collision recovery coefficient calibration value obtained in step 4.2, the rolling friction coefficient calibration value obtained in step 4.3 and the sliding friction coefficient calibration value obtained in step 4.4, the calibration of the contact parameters of the micron-sized spherical aluminum powder for energetic materials is obtained.

[0105] In this embodiment, the contact parameters of 13 μm spherical aluminum powder are collision recovery coefficient 0.54, sliding friction coefficient 0.64, rolling friction coefficient 0.58 and adsorption energy 0.003 J / m 3 .

[0106] Embodiment 2:

[0107] This embodiment provides a method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic materials. The main difference between this method and embodiment 1 is that the calibration order of the four contact parameters is different. In this embodiment, the calibration order is collision recovery coefficient, adsorption energy, rolling friction coefficient, and sliding friction coefficient. Figure 1 As shown, the method specifically comprises the following steps:

[0108] Step 1, take 35-micron spherical aluminum powder particles and conduct an angle of repose experiment to obtain the experimental angle of repose of the aluminum powder: weigh 15g, 25g, and 35g of micron-grade spherical aluminum powder with a diameter of 35 microns, respectively, and conduct angle of repose experiments, repeat 6 times at each mass, and obtain a total of 18 angle of repose values; in this embodiment, after calculation, it can be obtained that the average mass of the three groups of aluminum powder is 25g, and the average experimental angle of repose is 69.8°, which is the experimental angle of repose of the aluminum powder.

[0109] Step 2: Based on the discrete element method, a simulation geometric model of the angle of repose of micron-sized spherical aluminum powder is established. The modeling process includes: coarsening the aluminum powder particle size by 5 times (i.e., setting the aluminum powder particle size to 175 microns), setting the micron-sized spherical aluminum powder particles and the particle model to the JKR model, generating 25g of 35-micron spherical aluminum powder particles in the simulation model, and obtaining the simulation geometric model of the angle of repose of aluminum powder.

[0110] Step 3: Clarify the calibration order:

[0111] The collision recovery coefficient between 35-micron spherical aluminum powder particles was set to 0.5, the rolling friction coefficient was set to 0.5, the sliding friction coefficient was set to 0.5, and the adsorption energy was set to 0.001 J / m 3 , carried out the simulation work of the repose angle of 35-micron spherical aluminum powder.

[0112] In this embodiment, the simulated repose angle obtained is 49.8°, and the error with the experimental repose angle is 28.6%°, which is less than 30%. Therefore, the contact parameters are calibrated in the order of collision recovery coefficient, adsorption energy, rolling friction coefficient, and sliding friction coefficient until the error between the simulated repose angle and the experimental repose angle is less than or equal to 0.5%.

[0113] Step 4: Calibrate contact parameters:

[0114] Step 4.1, obtain the calibration value of the collision restitution coefficient.

[0115] The adsorption energy between 35 micron spherical aluminum powder particles is set to 0.0005 J / m 3 , the rolling friction coefficient is set to 0.5, and the sliding friction coefficient is set to 0.5; starting with the initial value of the collision recovery coefficient of 0.5, gradually increase and decrease the value of the collision recovery coefficient in the range of [0.4, 0.7] with an adjustment interval of 0.01, carry out a series of repose angle simulations, record the simulated repose angle obtained under each collision recovery coefficient, and stop the simulation when the collision recovery coefficient is assigned to 0.4 and 0.7. Select a simulation with the simulated repose angle closest to the experimental repose angle, and then set the value of the collision recovery coefficient corresponding to this simulation as the collision recovery coefficient calibration value.

[0116] In this embodiment, when the collision recovery coefficient is assigned a value of 0.65, the simulated repose angle of the 35-micron spherical aluminum powder particles reaches a maximum value of 51.57°, which is closest to the experimental repose angle with an error of 26.1%. The collision recovery coefficient of 0.65 is selected to carry out the next calibration work.

[0117] Step 4.2, obtain the adsorption energy calibration value:

[0118] The collision recovery coefficient between 35-micron spherical aluminum powder particles was set to 0.65, the rolling friction coefficient was set to 0.5, and the sliding friction coefficient was set to 0.5; the initial value of adsorption energy was 0.0005 J / m 3 Starting from 0.0005 J / m 3 The adsorption energy value was gradually increased by adjusting the interval, and a series of repose angle simulations were carried out. The simulated repose angle obtained under each adsorption energy was recorded until the adsorption energy value was 0.005 J / m 3 Stop the simulation.

[0119] A simulation in which the simulated angle of repose is closest to the experimental angle of repose is selected, and then the value of the collision restitution coefficient corresponding to this simulation is set as the collision restitution coefficient calibration value; if serious particle agglomeration occurs during the simulation in which the simulated angle of repose is closest to the experimental angle of repose, a simulation in which the simulated angle of repose is closest to the experimental angle of repose and no serious particle agglomeration occurs is selected, and then the adsorption energy value corresponding to this simulation is set as the adsorption energy calibration value.

[0120] In this embodiment, the simulated repose angle results obtained under each adsorption energy are shown in Table 1:

[0121] Table 1. Simulated repose angles obtained with different adsorption energies

[0122] <![CDATA[Adsorption energy / J m 3 > Simulated repose angle / ° <![CDATA[Adsorption energy / J m 3 > Simulated repose angle / ° 0.0005 51.57 0.0035 68.99 0.001 53.15 0.004 72.31 0.0015 55.81 0.0045 76.27 0.002 58.94 0.005 79.38 0.0025 61.57 0.003 64.47

[0123] It can be seen from Table 1 that when the adsorption energy is assigned to 0.0035 J / m 3 When 0.0035 J / m was selected, the simulated repose angle was 68.99°, which was closest to the experimental repose angle of aluminum powder (69.8°), with an error of 1.16%. No serious particle agglomeration was observed during the simulation, which was consistent with the actual experimental phenomenon. 3 The adsorption capacity can be used to carry out the next calibration work.

[0124] Step 4.3, obtain the rolling friction coefficient calibration value:

[0125] The adsorption energy between 35 micron spherical aluminum powder particles is set to 0.0035 J / m 3 , the collision recovery coefficient is set to 0.65, and the sliding friction coefficient is set to 0.5; the simulated repose angle obtained in step 2 is 68.99°, which is smaller than the experimental repose angle of 69.8°. Starting with the initial value of the rolling friction coefficient of 0.5, the assignment of the collision recovery coefficient is gradually increased with an adjustment interval of 0.01, and a series of repose angle simulations are carried out. The simulated repose angle obtained under each rolling friction coefficient is recorded until the assignment of the rolling friction coefficient is 0.6 and the simulation is stopped. Select a simulation with the simulated repose angle closest to the experimental repose angle, and then set the assignment of the rolling friction coefficient corresponding to this simulation as the rolling friction coefficient calibration value.

[0126] In this embodiment, when the rolling friction coefficient is assigned a value of 0.58, the simulated repose angle is 69.7°, which is closest to the experimental repose angle, with an error of 0.14%, which is less than 0.5%.

[0127] Step 4.4, obtain the calibration value of sliding friction coefficient:

[0128] Since the error between the simulated repose angle and the experimental repose angle in step 4.3 is less than 0.5%, 0.5 is directly taken as the calibration value of the sliding friction coefficient.

[0129] Step five, combining the calibration value of the sliding friction coefficient obtained in step 4.1, the calibration value of the collision recovery coefficient obtained in step 4.2, the calibration value of the adsorption energy obtained in step 4.3, and the calibration value of the rolling friction coefficient obtained in step 4.4, the calibration of the contact parameters of the micron-sized spherical aluminum powder for energetic materials is completed.

[0130] In this embodiment, the contact parameters of 35 μm spherical aluminum powder particles are collision recovery coefficient 0.65, sliding friction coefficient 0.5, rolling friction coefficient 0.58 and adsorption energy 0.0035 J / m 3 .

[0131] Comparative Example 1:

[0132] This comparative example provides a method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic materials. The method is basically the same as Example 1, except that in step 2, the coarsening multiple of the aluminum powder particle size during modeling is different. In this example, the coarsening multiple of the aluminum powder particle size during modeling is set to 1 to 2 times. As a result, the multiple is too small and the calculation cycle is too long, so the simulation result cannot be obtained.

[0133] Comparative Example 2:

[0134] This comparative example provides a method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic materials. The method is basically the same as Example 1, except that in step 2, the coarsening multiples of the aluminum powder particle size during modeling are different. In this example, the coarsening multiple of the aluminum powder particle size during modeling is set to 15 to 20 times. As a result, due to the large multiple, the simulation is distorted and no effective simulation results are obtained.

Claims

1. A method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic materials, characterized in that: The method specifically comprises the following steps: Step 1, taking micron-sized spherical aluminum powder and conducting a repose angle experiment to obtain an experimental repose angle of the micron-sized spherical aluminum powder; Step 2: Based on the discrete element method, a simulation geometric model of the repose angle of micron-sized spherical aluminum powder is established; Step 3: Clarify the calibration order: The values ​​of the contact parameters of the micron-sized spherical aluminum powder are set to carry out the simulation of the angle of repose; the contact parameters of the micron-sized spherical aluminum powder include the collision recovery coefficient, rolling friction coefficient, sliding friction coefficient and adsorption energy between the micron-sized spherical aluminum powder particles; If the error between the obtained simulated repose angle and the experimental repose angle obtained in step 1 is greater than 30%, the calibration order is determined as: adsorption energy calibration, collision recovery coefficient calibration, rolling friction coefficient calibration, sliding friction coefficient calibration; If the error between the obtained simulated repose angle and the experimental repose angle obtained in step 1 is less than or equal to 30%, the calibration order is determined as: collision recovery coefficient calibration, adsorption energy calibration, rolling friction coefficient calibration, sliding friction coefficient calibration; Step 4: Calibrate contact parameters: According to the order determined in step 3, the repose angle simulation work is carried out to obtain the calibration value of the contact parameters of micron-sized spherical aluminum powder; Step five, integrating the calibration values ​​of the contact parameters obtained in step four, thus completing the calibration of the contact parameters of the micron-sized spherical aluminum powder for energetic materials.

2. The method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic materials according to claim 1, characterized in that: In step 2, during modeling, the coarsening multiple of the particle size of the micron-sized spherical aluminum powder is 3 to 10 times.

3. The method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic materials according to claim 1, characterized in that: The step 4 specifically includes the following steps: Step 4.1, obtain the adsorption energy calibration value: The collision recovery coefficient between micron-sized spherical aluminum powder particles is set to e, e = 0.5; the rolling friction coefficient is set to δ, δ = 0.5; the sliding friction coefficient is set to μ, μ = 0.5; Starting from the initial value of adsorption energy Eads0, Eads0 = 0.0005 J / m 3 , gradually increase the adsorption energy value with the adjustment interval of ΔEads, and carry out a series of simulation work on the angle of repose, 0.0001J / m 3 ≤ΔEads≤0.0005J / m 3 ; Record the simulated repose angle obtained at each adsorption energy until the adsorption energy is assigned to 0.005 J / m 3 Stop the simulation work; If the errors between all simulated repose angles and experimental repose angles are greater than 0.5%, and no serious particle agglomeration is observed during the simulation, then select a simulation with the simulated repose angle closest to the experimental repose angle, and then set the adsorption energy corresponding to this simulation as the adsorption energy calibration value, and proceed to step 4.2; If the errors between all simulated repose angles and experimental repose angles are greater than 0.5%, but serious particle agglomeration occurs during the simulation in which the simulated repose angle is closest to the experimental repose angle, select the simulation in which the simulated repose angle is closest to the experimental repose angle and no serious particle agglomeration occurs, and then set the adsorption energy value corresponding to this simulation as the adsorption energy calibration value, and proceed to step 4.2; If the error between a simulated repose angle and an experimental repose angle is less than or equal to 0.5%, the adsorption energy value corresponding to this simulation is set as the adsorption energy calibration value, the collision recovery coefficient calibration value is e, the rolling friction coefficient calibration value is δ, and the sliding friction coefficient calibration value is μ, and step 5 is directly performed; Step 4.2, obtain the collision recovery coefficient calibration value: The adsorption energy between micron-sized spherical aluminum powder particles is set to the adsorption energy calibration value obtained in step 4.1; the rolling friction coefficient is set to δ, δ = 0.5; the sliding friction coefficient is set to μ, μ = 0.5; Starting from the initial value e0 of the collision recovery coefficient, e0=0.5, gradually increase or decrease the value of the collision recovery coefficient in the range of [0.4, 0.7] with an adjustment interval of Δe, and carry out a series of repose angle simulations, 0.01≤Δe≤0.02; record the simulated repose angle obtained under each collision recovery coefficient; If the errors between all simulated repose angles and experimental repose angles are greater than 0.5%, select a simulation with the simulated repose angle closest to the experimental repose angle, and then set the value of the collision restitution coefficient corresponding to this simulation as the collision restitution coefficient calibration value, and proceed to step 4.3; If the error between a simulated repose angle and an experimental repose angle is less than or equal to 0.5%, the collision recovery coefficient value corresponding to this simulation is set as the collision recovery coefficient calibration value, the rolling friction coefficient calibration value is δ, and the sliding friction coefficient calibration value is μ, and step 5 is directly performed; Step 4.3, obtain the rolling friction coefficient calibration value: The adsorption energy between micron-sized spherical aluminum powder particles is set to the adsorption energy calibration value obtained in step 4.1; the collision recovery coefficient is set to the collision recovery coefficient calibration value obtained in step 4.2; and the sliding friction coefficient is set to μ; Starting with the initial value δ0 of the rolling friction coefficient, δ0=0.5, if the simulated repose angle finally obtained in step 4.2 is greater than the experimental repose angle, then gradually reduce the assigned value of the rolling friction coefficient by an adjustment interval of Δδ in the range of [0.3, 0.5], and carry out a series of repose angle simulations, 0.01≤Δδ≤0.03; record the simulated repose angle obtained under each rolling friction coefficient; - If the simulated repose angle finally obtained in step 4.2 is smaller than the experimental repose angle, gradually increase the assigned value of the rolling friction coefficient in the range of [0.5, 0.6] with an adjustment interval of Δδ, and carry out a series of repose angle simulations, 0.01≤Δδ≤0.03; record the simulated repose angle obtained under each rolling friction coefficient; - If the errors between all simulated repose angles and experimental repose angles are greater than 0.5%, select a simulation with the simulated repose angle closest to the experimental repose angle, and then set the value of the rolling friction coefficient corresponding to this simulation as the rolling friction coefficient calibration value, and proceed to step 4.4; If the error between a certain simulated repose angle and an experimental repose angle is less than or equal to 0.5%, the rolling friction coefficient value corresponding to this simulation is set as the rolling friction coefficient calibration value, and the sliding friction coefficient calibration value is μ, and step five is directly performed; Step 4.4, obtain the calibration value of sliding friction coefficient: The adsorption energy between micron-sized spherical aluminum powder particles is set to the adsorption energy calibration value obtained in step 4.1; the collision recovery coefficient is set to the collision recovery coefficient calibration value obtained in step 4.2; and the rolling friction coefficient is set to the rolling friction coefficient calibration value obtained in step 4.3; Starting with the initial value μ0 of the sliding friction coefficient, μ0=0.5, if the simulated repose angle finally obtained in step 4.3 is greater than the experimental repose angle, then gradually reduce the assigned value of the sliding friction coefficient in the range of [0.4, 0.5] with an adjustment interval of Δμ, and carry out a series of repose angle simulations, 0.02≤Δμ≤0.04; record the simulated repose angle obtained under each sliding friction coefficient; - If the simulated repose angle finally obtained in step 4.3 is smaller than the experimental repose angle, gradually increase the assigned value of the sliding friction coefficient in the range of [0.5, 0.8] with an adjustment interval of Δμ, and carry out a series of repose angle simulations, 0.02≤Δμ≤0.04; record the simulated repose angle obtained under each sliding friction coefficient; - Select a simulation in which the simulated repose angle is closest to the experimental repose angle, then set the value of the sliding friction coefficient corresponding to this simulation as the sliding friction coefficient calibration value, and proceed to step five.

4. The method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic materials according to claim 1, characterized in that: The step 4 specifically includes the following steps: Step 4.1, obtain the collision restitution coefficient calibration value: The adsorption energy between micron-sized spherical aluminum powder particles is set to Eads, Eads = 0.0005 J / m 3 ; Set the rolling friction coefficient to δ, δ = 0.5; Set the sliding friction coefficient to μ, μ = 0.5; Starting from the initial value e0 of the collision recovery coefficient, e0=0.5, gradually increase or decrease the value of the collision recovery coefficient in the range of [0.4, 0.7] with an adjustment interval of Δe, and carry out a series of repose angle simulations, 0.01≤Δe≤0.02; record the simulated repose angle obtained under each collision recovery coefficient; If the errors between all simulated repose angles and experimental repose angles are greater than 0.5%, select a simulation with the simulated repose angle closest to the experimental repose angle, and then set the value of the collision restitution coefficient corresponding to this simulation as the collision restitution coefficient calibration value, and proceed to step 4.2; If the error between a simulated repose angle and an experimental repose angle is less than or equal to 0.5%, the collision recovery coefficient value corresponding to this simulation is set as the collision recovery coefficient calibration value, the rolling friction coefficient calibration value is δ, the sliding friction coefficient calibration value is μ, the adsorption energy calibration value is Eads, and step 5 is directly performed; Step 4.2, obtain the adsorption energy calibration value: The collision recovery coefficient between micron-sized spherical aluminum powder particles is set to the collision recovery coefficient calibration value obtained in step 4.1; the rolling friction coefficient is set to δ, δ = 0.5; the sliding friction coefficient is set to μ, μ = 0.5; Starting from the initial value of adsorption energy Eads0, Eads0 = 0.0005 J / m 3 , gradually increase the adsorption energy value with the adjustment interval of ΔEads, and carry out a series of simulation work on the angle of repose, 0.0001J / m 3 ≤ΔEads≤0.0005J / m 3 ; Record the simulated repose angle obtained at each adsorption energy until the adsorption energy is assigned to 0.005 J / m 3 Stop the simulation work; If the errors between all simulated repose angles and experimental repose angles are greater than 0.5%, and no serious particle agglomeration is observed during the simulation, select a simulation with the simulated repose angle closest to the experimental repose angle, and then set the adsorption energy corresponding to this simulation as the adsorption energy calibration value, and proceed to step 4.3; If the errors between all simulated repose angles and experimental repose angles are greater than 0.5%, but serious particle agglomeration occurs during the simulation in which the simulated repose angle is closest to the experimental repose angle, select the simulation in which the simulated repose angle is closest to the experimental repose angle and no serious particle agglomeration occurs, and then set the adsorption energy value corresponding to this simulation as the adsorption energy calibration value, and proceed to step 4.3; If the error between a simulated repose angle and an experimental repose angle is less than or equal to 0.5%, the adsorption energy value corresponding to this simulation is set as the adsorption energy calibration value, the rolling friction coefficient calibration value is δ, and the sliding friction coefficient calibration value is μ, and step 5 is directly performed; Step 4.3, obtain the rolling friction coefficient calibration value: The collision recovery coefficient between micron-sized spherical aluminum powder particles is set to the collision recovery coefficient calibration value obtained in step 4.1; the adsorption energy is set to the adsorption energy calibration value obtained in step 4.2; and the sliding friction coefficient is set to μ; Starting with the initial value δ0 of the rolling friction coefficient, δ0=0.5, if the simulated repose angle finally obtained in step 4.2 is greater than the experimental repose angle, then gradually reduce the assigned value of the rolling friction coefficient by an adjustment interval of Δδ in the range of [0.3, 0.5], and carry out a series of repose angle simulations, 0.01≤Δδ≤0.03; record the simulated repose angle obtained under each rolling friction coefficient; - If the simulated repose angle finally obtained in step 4.2 is smaller than the experimental repose angle, gradually increase the assigned value of the rolling friction coefficient in the range of [0.5, 0.6] with an adjustment interval of Δδ, and carry out a series of repose angle simulations, 0.01≤Δδ≤0.03; record the simulated repose angle obtained under each rolling friction coefficient; - If the errors between all simulated repose angles and experimental repose angles are greater than 0.5%, select a simulation with the simulated repose angle closest to the experimental repose angle, and then set the value of the rolling friction coefficient corresponding to this simulation as the rolling friction coefficient calibration value, and proceed to step 4.4; If the error between a certain simulated repose angle and an experimental repose angle is less than or equal to 0.5%, the rolling friction coefficient value corresponding to this simulation is set as the rolling friction coefficient calibration value, and the sliding friction coefficient calibration value is μ, and step five is directly performed; Step 4.4, obtain the calibration value of sliding friction coefficient: The collision recovery coefficient between micron-sized spherical aluminum powder particles is set to the collision recovery coefficient calibration value obtained in step 4.1; the adsorption energy is set to the adsorption energy calibration value obtained in step 4.2; and the rolling friction coefficient is set to the rolling friction coefficient calibration value obtained in step 4.3; Starting with the initial value μ0 of the sliding friction coefficient, μ0=0.5, if the simulated repose angle finally obtained in step 4.3 is greater than the experimental repose angle, then gradually reduce the assigned value of the sliding friction coefficient by an adjustment interval of Δμ in the range of [0.4, 0.5], and carry out a series of repose angle simulations, 0.02≤Δμ≤0.04; record the simulated repose angle obtained under each sliding friction coefficient, and stop the simulation until the assigned value of the sliding friction coefficient is 0.4; If the simulated repose angle finally obtained in step 4.3 is smaller than the experimental repose angle, gradually increase the assigned value of the sliding friction coefficient in the range of [0.5, 0.8] with an adjustment interval of Δμ, and carry out a series of repose angle simulations, 0.02≤Δμ≤0.04; record the simulated repose angle obtained under each sliding friction coefficient; - Select a simulation in which the simulated repose angle is closest to the experimental repose angle, then set the value of the sliding friction coefficient corresponding to this simulation as the sliding friction coefficient calibration value, and proceed to step five.

5. The method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic materials according to claim 1, characterized in that: The diameter of the micron-grade spherical aluminum powder is 13 microns to 35 microns.

6. The method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic materials according to claim 1, characterized in that: The step 1 comprises: weighing multiple groups of micron-sized spherical aluminum powders of different masses; repeating the angle of repose experiment for each group of micron-sized spherical aluminum powders for several times to obtain multiple angle of repose values; calculating and obtaining the average experimental angle of repose α of the multiple groups of micron-sized spherical aluminum powders of different masses, and the average experimental angle of repose α is the experimental angle of repose of the aluminum powder.

7. The method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic materials according to claim 5, characterized in that: In step 1, the repose angle experiment is repeated 3 to 10 times for each group of micron-sized spherical aluminum powders.

8. The method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic materials according to claim 5, characterized in that: In step 1, the mass range of each group of micron-sized spherical aluminum powder is 10 g to 100 g, and the average mass of multiple groups of micron-sized spherical aluminum powders of different masses is W1.

9. The method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic materials according to claim 8, characterized in that: In step 2, the modeling process includes: setting the micron-sized spherical aluminum powder particles and the particle-to-particle model as the JKR model, generating W1 grams of micron-sized spherical aluminum powder particles in the simulation model, and obtaining the repose angle simulation geometric model of the aluminum powder.

10. The method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic materials according to claim 1, characterized in that: In step 3, the collision recovery coefficient between micron-sized spherical aluminum powder particles is set to e1, 0.4≤e1≤0.5; the rolling friction coefficient is set to δ1, 0.4≤δ1≤0.5; the sliding friction coefficient is set to μ1, 0.4≤μ1≤0.5; the adsorption energy is set to Eads1, 0.0005 J / m 3 ≤Eads1≤0.0015J / m 3 .

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