Method for calibrating contact parameters of microsized spherical aluminum powder for energetic materials

Abstract

The application provides a kind of microspherical aluminum powder contact parameter calibration method for energetic materials, and the basic principle of the method is to combine discrete element simulation-experiment, compare simulation angle of repose and experimental angle of repose error, take different calibration order for different error, and gradually complete the contact parameter calibration of microspherical aluminum powder for energetic materials.The application first proposes that for microspherical aluminum powder, the inter-particle collision restitution coefficient, sliding friction coefficient, rolling friction coefficient and adsorption energy of the four contact parameters need to be calibrated, and the application first clearly defines the appropriate roughening range of aluminum powder when modeling, the calibration order under different conditions and the contact parameter calibration range, the application reduces the workload of microspherical aluminum powder contact parameter calibration, and promotes the efficient preparation of energetic materials.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of energetic material manufacturing, and relates to parameter calibration of raw materials, in particular to a method for calibrating contact parameters of micron-sized spherical aluminum powder for energetic materials. BACKGROUND

[0002] For most energetic materials, micron-sized spherical aluminum powder is a core component, and its uniform distribution at the microscopic level is of great significance for efficient and safe preparation of energetic materials. In the preparation process of energetic materials, existing detection means cannot observe the distribution of aluminum powder in real time, and simulation means need to be relied on to analyze the movement law of aluminum powder, thereby guiding the control of actual preparation process parameters. In order to accurately predict the movement of micron-sized spherical aluminum powder, its contact parameters need to be determined. Since there are many variables affecting the fluidity of micron-sized spherical aluminum powder at the microscopic level, the calibration is difficult and laborious, and a method for calibrating the contact parameters of micron-sized spherical aluminum powder for energetic materials needs to be proposed to guide the rapid and accurate calibration of the contact parameters and provide support for efficient preparation of energetic materials. SUMMARY

[0003] In view of the problems in the prior art, the purpose of the present application is to provide a method for calibrating the contact parameters of micron-sized spherical aluminum powder for energetic materials, which solves the technical problems of too many variables, high calibration difficulty and large workload in calibrating the contact parameters of micron-sized spherical aluminum powder for energetic materials in the prior art.

[0004] To solve the above technical problems, the present application adopts the following technical solutions:

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

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

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

[0008] Step 3: Determine the calibration sequence:

[0009] Set the values of the contact parameters of the micron-sized spherical aluminum powder, and perform a repose angle simulation; the contact parameters of the micron-sized spherical aluminum powder include the collision restitution coefficient, the rolling friction coefficient, the sliding friction coefficient and the adsorption energy between the particles of the micron-sized spherical aluminum powder.

[0010] If the error between the obtained simulation rest angle and the experimental rest angle obtained in step one is greater than 30%, the calibration order is determined as follows: adsorption energy calibration, collision restitution coefficient calibration, rolling friction coefficient calibration, and sliding friction coefficient calibration.

[0011] If the error between the obtained simulation rest angle and the experimental rest angle obtained in step one is less than or equal to 30%, the calibration order is determined as follows: collision restitution coefficient calibration, adsorption energy calibration, rolling friction coefficient calibration, and sliding friction coefficient calibration.

[0012] Step four, contact parameter calibration is carried out:

[0013] According to the order determined in step three, the rest angle simulation work is carried out to obtain the calibration value of the contact parameter of the micron-level spherical aluminum powder.

[0014] Step five, the calibration value of the contact parameter obtained in step four is integrated, and the calibration work of the contact parameter of the micron-level spherical aluminum powder for energetic materials is completed.

[0015] The application also has the following technical features:

[0016] Specifically and preferably, in step two, when modeling, the roughening multiple of the particle size of the micron-level spherical aluminum powder is 3-10 times.

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

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

[0019] The collision restitution coefficient between the micron-level spherical aluminum powder particles and the 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] Taking the initial value Eads0 of the adsorption energy as the starting point, Eads0=0.0005J / m 3 The assignment of the adsorption energy is gradually increased by the adjustment interval of ΔEads, and a series of rest angle simulation work is carried out, 0.0001J / m 3 ≤ΔEads≤0.0005J / m 3 ; the obtained simulation rest angle under each adsorption energy is recorded, and the simulation work is stopped when the assignment of the adsorption energy is 0.005J / m 3 .

[0021] If the error between all simulation rest angles and experimental rest angles is greater than 0.5%, and no serious particle agglomeration phenomenon is observed during the simulation, the simulation rest angle closest to the experimental rest angle is selected, and then the assignment of the adsorption energy corresponding to this simulation is set as the adsorption energy calibration value, and step 4.2 is continued.

[0022] If the error between all the simulated repose angles and the experimental repose angle is greater than 0.5%, but the simulated repose angle is closest to the experimental repose angle in one simulation process, and serious particle agglomeration does not occur in the simulation, then the simulation in which the simulated repose angle is closest to the experimental repose angle and in which serious particle agglomeration does not occur is selected, and the adsorption energy value corresponding to the simulation is set as the adsorption energy calibration value, and step 4.2 is continued.

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

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

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

[0026] With the initial value e0 of the collision restitution coefficient as the starting point, e0 = 0.5, the value of the collision restitution coefficient is gradually increased or decreased by an adjustment interval Δe in the range of [0.4, 0.7], a series of repose angle simulations are performed, 0.01 ≤ Δe ≤ 0.02; and the simulated repose angle obtained under each collision restitution coefficient is recorded until the value of the collision restitution coefficient is 0.4 or 0.7, and the simulation is stopped.

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

[0028] If the error between a simulated repose angle and the experimental repose angle is less than or equal to 0.5%, then the value of the collision restitution coefficient corresponding to the simulation is set as the collision restitution coefficient calibration value, the rolling friction coefficient calibration value is δ, and 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 the micron-sized spherical aluminum powder particles and the particles is set as the adsorption energy calibration value obtained in step 4.1; the collision restitution coefficient is set as the collision restitution coefficient calibration value obtained in step 4.2; and the sliding friction coefficient is set as μ.

[0031] Take the initial value of the rolling friction coefficient δ0 as the starting point, δ0 = 0.5, if the final simulation of the rest angle obtained in step 4.2 is greater than the experimental rest angle, gradually reduce the assignment of the rolling friction coefficient in the range of [0.3, 0.5] with the adjustment interval of Δδ, carry out a series of rest angle simulations, 0.01 ≤ Δδ ≤ 0.03; record the simulation rest angle obtained under each rolling friction coefficient until the assignment of the rolling friction coefficient is 0.3 to stop the simulation.

[0032] If the final simulation of the rest angle obtained in step 4.2 is less than the experimental rest angle, gradually increase the assignment of the rolling friction coefficient in the range of [0.5, 0.6] with the adjustment interval of Δδ, carry out a series of rest angle simulations, 0.01 ≤ Δδ ≤ 0.03; record the simulation rest angle obtained under each rolling friction coefficient until the assignment of the rolling friction coefficient is 0.6 to stop the simulation.

[0033] If the error of all simulation rest angles and experimental rest angles is greater than 0.5%, select the simulation with the closest simulation rest angle and experimental rest angle, and then set the assignment of the rolling friction coefficient corresponding to this simulation as the rolling friction coefficient calibration value, and continue to step 4.4.

[0034] If the error of a certain simulation rest angle and experimental rest angle is less than or equal to 0.5%, set the assignment of the rolling friction coefficient corresponding to this simulation as the rolling friction coefficient calibration value, and the sliding friction coefficient calibration value is μ, directly proceed to step five.

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

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

[0037] Take the initial value of the sliding friction coefficient μ0 as the starting point, μ0 = 0.5, if the final simulation of the rest angle obtained in step 4.3 is greater than the experimental rest angle, gradually reduce the assignment of the sliding friction coefficient in the range of [0.4, 0.5] with the adjustment interval of Δμ, carry out a series of rest angle simulations, 0.02 ≤ Δμ ≤ 0.04; record the simulation rest angle obtained under each sliding friction coefficient until the assignment of the sliding friction coefficient is 0.4 to stop the simulation.

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

[0039] Select the simulation with the simulation rest angle closest to the experimental rest angle, and set the assigned value of the sliding friction coefficient corresponding to the simulation as the sliding friction coefficient calibration value, and continue step five.

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

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

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

[0043] Take the initial value e0 of the collision restitution coefficient as the starting point, e0=0.5, gradually increase or decrease the assigned value of the collision restitution coefficient in the adjustment interval of Δe in the range of [0.4, 0.7], carry out a series of rest angle simulations, 0.01≤Δe≤0.02; record the simulation rest angle obtained under each collision restitution coefficient until the assigned value of the collision restitution coefficient is 0.4 or 0.7 to stop the simulation.

[0044] If the error of all simulation rest angles and experimental rest angles is greater than 0.5%, select the simulation with the simulation rest angle closest to the experimental rest angle, and set the assigned value of the collision restitution coefficient corresponding to the simulation as the collision restitution coefficient calibration value, and continue step 4.2.

[0045] If the error of a certain simulation rest angle and the experimental rest angle is less than or equal to 0.5%, set the assigned value of the collision restitution coefficient corresponding to the simulation as the collision restitution coefficient calibration value, the rolling friction coefficient calibration value is δ, the sliding friction coefficient calibration value is μ, and the adsorption energy calibration value is Eads, and directly proceed to step five.

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

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

[0048] Take the initial value of adsorption energy Eads0 as the starting point, Eads0 = 0.0005 J / m 3 , gradually increase the assignment of adsorption energy with the adjustment interval of ΔEads, carry out a series of angle of repose simulation work, 0.0001 J / m 3 ≤ ΔEads ≤ 0.0005 J / m 3 ; record the simulation angle of repose obtained under each adsorption energy until the assignment of adsorption energy is 0.005 J / m 3 , stop the simulation work.

[0049] If the error of all simulation angles of repose and experimental angles of repose is greater than 0.5%, and no serious particle agglomeration phenomenon is observed in the simulation process, select the simulation with the closest simulation angle of repose and experimental angle of repose, and then set the assignment of adsorption energy corresponding to this simulation as the adsorption energy calibration value, and continue to step 4.3.

[0050] If the error of all simulation angles of repose and experimental angles of repose is greater than 0.5%, but the simulation with the closest simulation angle of repose and experimental angle of repose appears serious particle agglomeration phenomenon in the simulation process, select the simulation with the closest simulation angle of repose and experimental angle of repose, and no serious particle agglomeration phenomenon, and then set the assignment of adsorption energy corresponding to this simulation as the adsorption energy calibration value, and continue to step 4.3.

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

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

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

[0054] Take the initial value of rolling friction coefficient δ0 as the starting point, δ0 = 0.5, if the final simulation angle of repose obtained in step 4.2 is greater than the experimental angle of repose, gradually decrease the assignment of rolling friction coefficient in the range of [0.3, 0.5] with the adjustment interval of Δδ, carry out a series of angle of repose simulation, 0.01 ≤ Δδ ≤ 0.03; record the simulation angle of repose obtained under each rolling friction coefficient, until the assignment of rolling friction coefficient is 0.3, stop the simulation.

[0055] If the simulation rest angle obtained in step 4.2 is less than the experimental rest angle, gradually increase the assigned value of the rolling friction coefficient in the range of [0.5, 0.6] at an adjustment interval of Δδ, carry out a series of rest angle simulations, 0.01≤Δδ≤0.03, and record the simulation rest angle obtained at each rolling friction coefficient until the assigned value of the rolling friction coefficient is 0.6.

[0056] If the error of all simulation rest angles and the experimental rest angle is greater than 0.5%, select the simulation with the simulation rest angle closest to the experimental rest angle, and then set the assigned value of the rolling friction coefficient corresponding to this simulation as the rolling friction coefficient calibration value, and continue to step 4.4.

[0057] If the error of a certain simulation rest angle and the experimental rest angle is less than or equal to 0.5%, set the assigned value of the rolling friction coefficient corresponding to this simulation as the rolling friction coefficient calibration value, and the sliding friction coefficient calibration value is μ, and directly proceed to step five.

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

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

[0060] Take the initial value of the sliding friction coefficient μ0 as the starting point, μ0=0.5, if the simulation rest angle obtained in step 4.3 is greater than the experimental rest angle, gradually decrease the assigned value of the sliding friction coefficient in the range of [0.4, 0.5] at an adjustment interval of Δμ, carry out a series of rest angle simulations, 0.02≤Δμ≤0.04; record the simulation rest angle obtained at each sliding friction coefficient until the assigned value of the sliding friction coefficient is 0.4.

[0061] If the simulation rest angle obtained in step 4.3 is less than the experimental rest angle, gradually increase the assigned value of the sliding friction coefficient in the range of [0.5, 0.8] at an adjustment interval of Δμ, carry out a series of rest angle simulations, 0.02≤Δμ≤0.04; record the simulation rest angle obtained at each sliding friction coefficient until the assigned value of the sliding friction coefficient is 0.8.

[0062] Select the simulation with the simulation rest angle closest to the experimental rest angle, and then set the assigned value of the sliding friction coefficient corresponding to this simulation as the sliding friction coefficient calibration value, and continue to step five.

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

[0064] Specifically, the step one comprises: weighing a plurality of groups of microspherical aluminum powder with different mass; repeatedly performing several repose angle experiments on each group of microspherical aluminum powder to obtain a plurality of repose angle values; and calculating and obtaining the average experimental repose angle of the plurality of groups of microspherical aluminum powder with different mass, which is the experimental repose angle of the aluminum powder.

[0065] Specifically and preferably, in step one, the repose angle experiment is repeated 3-10 times for each group of microspherical aluminum powder.

[0066] Specifically and preferably, in step one, the mass of each group of microspherical aluminum powder ranges from 10g to 100g, and the average mass of the plurality of groups of microspherical aluminum powder with different mass is W1.

[0067] Specifically, in step two, the modeling process comprises: setting the inter-particle model of the microspherical aluminum powder as the JKR model, generating W1 grams of microspherical aluminum powder particles in the simulation model, and obtaining the repose angle simulation geometric model of the aluminum powder.

[0068] Specifically, in step three, the inter-particle collision restitution coefficient of the microspherical aluminum powder particles is set as e1, e1=0.5; the rolling friction coefficient is set as δ1, δ1=0.5; the sliding friction coefficient is set as μ1, μ1=0.5; and the adsorption energy is set as Eads1, Eads1=0.0005J / m 3 .

[0069] Compared with the prior art, the present application has the following beneficial technical effects:

[0070] (I) The present application first proposes that, for microspherical aluminum powder, the inter-particle collision restitution coefficient, sliding friction coefficient, rolling friction coefficient and adsorption energy need to be calibrated. Among them, the inter-particle collision restitution coefficient of the microspherical aluminum powder reflects the particle collision type, the sliding friction coefficient and the rolling friction coefficient represent the flowability of the particles, in addition, due to the small particle size of the microspherical aluminum powder, the surface adsorption between particles is large, and the particles are easy to agglomerate during preparation, therefore, the adsorption energy between the particles of the microspherical aluminum powder also needs to be considered.

[0071] (II) Based on the above four contact parameters, the present application first proposes a microspherical aluminum powder contact parameter calibration method for energetic material manufacturing combined with discrete element simulation, which clearly defines the appropriate roughening range of the aluminum powder during modeling, the calibration sequence under different conditions and the calibration range of the contact parameters. Through the repose angle experiment, the repose angle is obtained, and the discrete element simulation method is used to further calibrate the contact parameters of the microspherical aluminum powder, complete the contact parameter calibration of the microspherical aluminum powder suitable for the manufacturing of energetic materials, reduce the workload of the contact parameter calibration of the microspherical aluminum powder, and promote the efficient preparation of energetic materials. Attached Figure Description

[0072] Figure 1 A schematic flowchart illustrating the calibration method for contact parameters of micron-sized spherical aluminum powder used in energetic materials.

[0073] The technical solution of the present invention will be further described below with reference to the embodiments. Detailed Implementation

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

[0075] The angle of repose test is performed according to the conventional angle of repose test method known in the prior art, and in accordance with the Chinese national standard GB / T 16913.5-1997.

[0076] The geometric model for the angle of repose simulation and the simulation work were both conducted using EDEM software (a multi-purpose discrete element method modeling software) known in existing technology. Unless otherwise specified, all parameters used are the software default parameters.

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

[0078] The JKR model is a conventional theoretical model known in the art. Specifically, it is a theoretical model for describing the adhesive forces between solid materials, describing the adhesive forces between two solid surfaces, particularly in the elastic deformation region within the contact area.

[0079] Following the above technical solutions, 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 modifications made based on the technical solutions of this application fall within the protection scope of the present invention.

[0080] Example 1:

[0081] This embodiment presents 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 with experiment, compare the errors of the simulated angle of repose and the experimental angle of repose, and adopt different calibration sequences for different errors to gradually complete the calibration of the contact parameters of micron-sized spherical aluminum powder for energetic materials. For example... Figure 1 As shown, the method specifically includes the following steps:

[0082] Step one, take 13 micron spherical aluminum powder particles and carry out the angle of repose experiment, obtain the experimental angle of repose of aluminum powder: 10g, 20g, 30g of 13 micron spherical aluminum powder with a diameter of 13 microns are weighed respectively, and the angle of repose experiment is carried out respectively, each mass is repeated for 6 times, a total of 18 angle of repose values are obtained; in this embodiment, after calculation, 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 two, based on the discrete element method, an angle of repose simulation geometric model of micron spherical aluminum powder is established, the modeling process includes: the particle size of aluminum powder is coarsened by 10 times (i.e. the particle size of aluminum powder is set to 130 microns), the inter-particle model of micron spherical aluminum powder particles is set as JKR model, 20g of 13 micron spherical aluminum powder particles are generated in the simulation model, and the angle of repose simulation geometric model of aluminum powder is obtained.

[0084] Step three, the calibration order is determined:

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

[0086] In this embodiment, the simulation angle of repose obtained is 45.27°, and the error with the experimental angle of repose is 39.23°, which is greater than 30%, so the contact parameter calibration is carried out in the order of adsorption energy, collision restitution coefficient, rolling friction coefficient and sliding friction coefficient (as shown in steps 4.1 to 4.4 below), until the error between the simulation angle of repose and the experimental angle of repose is less than or equal to 0.5%.

[0087] Step four, the contact parameter calibration is carried out:

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

[0089] The collision restitution coefficient between 13 micron spherical aluminum powder particles and particles is set to 0.5, the rolling friction coefficient is set to 0.5, and the sliding friction coefficient is set to 0.5; the initial value of the adsorption energy is 0.0005J / m 3 , the adsorption energy is gradually increased by an adjustment interval of 0.0005J / m 3 , a series of angle of repose simulation work is carried out, the simulation angle of repose obtained at each adsorption energy is recorded, and the simulation work is stopped when the assignment value of the adsorption energy is 0.005J / m 3 .

[0090] selecting a simulation with the closest simulation repose angle to the experimental repose angle, and setting the value of the adsorption energy corresponding to the simulation as the calibration value of the adsorption energy.

[0091] In the embodiment, the simulation repose angles obtained under each adsorption energy are shown in Table 1:

[0092] Table 1: Simulation repose angles obtained under different adsorption energies

[0093] Adsorption energy / J m 3 ]] Simulated angle of repose / ° Adsorption energy / J m 3 ]] Simulated angle of repose / ° 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] As shown in Table 1, when the value of the adsorption energy is 0.0035 J / m 3 , the simulation repose angle is 75.4°, which is closest to the experimental repose angle of the aluminum powder 74.5°, with an error of 1.2%. However, when the adsorption energy is greater than 0.003 J / m 3 , serious particle agglomeration is observed in the simulation, which is inconsistent with the actual experimental phenomenon. Therefore, the value of the adsorption energy closest to the experimental phenomenon and the experimental repose angle is selected as 0.003 J / m 3 . At this time, the simulation repose angle is 70.31°, with an error of 5.6% from the experimental repose angle. The adsorption energy of 0.003 J / m 3 is selected for the next calibration work.

[0095] Step 4.2: Calibration of the coefficient of restitution

[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 from the initial value of the coefficient of restitution 0.5, gradually increase and decrease the value of the coefficient of restitution in the range of [0.4, 0.7] with an adjustment interval of 0.01, and carry out a series of repose angle simulations. Record the simulation repose angle obtained under each coefficient of restitution until the value of the coefficient of restitution is 0.4 and 0.7. Select a simulation with the closest simulation repose angle to the experimental repose angle, and set the value of the coefficient of restitution corresponding to the simulation as the calibration value of the coefficient of restitution.

[0097] In this embodiment, when the collision restitution coefficient is assigned as 0.54, the simulation angle of repose of the 13-micron spherical aluminum powder reaches the maximum value of 72.19°, which is closest to the experimental angle of repose, with an error of 3.1%. Therefore, the collision restitution coefficient of 0.54 is selected for the next calibration.

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

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

[0100] In this embodiment, when the assignment value of the rolling friction coefficient is 0.58, the simulation angle of repose is 74.1°, which is closest to the experimental angle of repose, with an error of 0.54%. Therefore, the rolling friction coefficient of 0.58 is selected for the next calibration.

[0101] Step 4.4, calibration of the sliding friction coefficient:

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

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

[0104] Step five, the adsorption energy calibration value obtained in step 4.1, the collision restitution 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 are integrated, that is, 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 the 13-micron spherical aluminum powder are a collision restitution coefficient of 0.54, a sliding friction coefficient of 0.64, a rolling friction coefficient of 0.58 and an adsorption energy of 0.003 J / m 3 .

[0106] Example 2:

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

[0108] Step one, take 35-micron spherical aluminum powder particles and carry out the angle of repose experiment, obtain the experimental angle of repose of the aluminum powder: weigh 15g, 25g, 35g of micron-sized spherical aluminum powder with a diameter of 35 microns respectively, carry out the angle of repose experiment respectively, repeat 6 times under each mass, a total of 18 angle of repose values are obtained; in this embodiment, after calculation, 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 two, based on the discrete element method, an angle of repose simulation geometric model of micron-sized spherical aluminum powder is established, the modeling process includes: the aluminum powder particle size is coarsened by 5 times (i.e. the aluminum powder particle size is set to 175 microns), the inter-particle model of micron-sized spherical aluminum powder particles is set as JKR model, 25g of 35-micron spherical aluminum powder particles are generated in the simulation model, and the angle of repose simulation geometric model of the aluminum powder is obtained.

[0110] Step three, the calibration order is determined:

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

[0112] In this embodiment, the obtained simulation angle of repose is 49.8°, and the error with the experimental angle of repose is 28.6%°, which is less than 30%, so the contact parameter calibration is performed in the order of the collision restitution coefficient, the adsorption energy, the rolling friction coefficient, and the sliding friction coefficient, until the error between the simulation angle of repose and the experimental angle of repose is less than or equal to 0.5%.

[0113] Step four, contact parameter calibration is performed:

[0114] Step 4.1, the collision restitution coefficient calibration value is obtained.

[0115] The 35-micron spherical aluminum powder particles and the inter-particle adsorption energy are 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; the initial value of the collision restitution coefficient is 0.5, and the assignment of the collision restitution coefficient is gradually increased and decreased by an adjustment interval of 0.01 in the range of [0.4, 0.7], a series of angle of repose simulation work is carried out, and the simulation angle of repose obtained under each collision restitution coefficient is recorded, until the assignment of the collision restitution coefficient is 0.4 and 0.7, the simulation is stopped. Select the simulation with the closest simulation angle of repose and experimental angle of repose, and then set the assignment of the collision restitution coefficient corresponding to this simulation as the collision restitution coefficient calibration value.

[0116] In this embodiment, when the assignment of the collision restitution coefficient is 0.65, the simulation angle of repose of the 35-micron spherical aluminum powder particles reaches the maximum value of 51.57°, which is closest to the experimental angle of repose, and the error is 26.1%, so the collision restitution coefficient of 0.65 is selected for the next calibration work.

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

[0118] The 35-micron spherical aluminum powder particles and the inter-particle collision restitution coefficient are set to 0.65, the rolling friction coefficient is set to 0.5, and the sliding friction coefficient is set to 0.5; the initial value of the adsorption energy is 0.0005 J / m 3 , and the assignment of the adsorption energy is gradually increased by an adjustment interval of 0.0005 J / m 3 , a series of angle of repose simulation work is carried out, and the simulation angle of repose obtained under each adsorption energy is recorded, until the assignment of the adsorption energy is 0.005 J / m 3 , the simulation work is stopped.

[0119] The simulation of the closest angle of repose to the experimental angle of repose is selected, and the collision restitution coefficient corresponding to the simulation is set as the collision restitution coefficient calibration value. If the simulation of the closest angle of repose to the experimental angle of repose is accompanied by serious particle agglomeration, the simulation of the closest angle of repose to the experimental angle of repose without serious particle agglomeration is selected, and the adsorption energy corresponding to the simulation is set as the adsorption energy calibration value.

[0120] In this embodiment, the simulation angle of repose obtained under each adsorption energy is shown in Table 1:

[0121] Table 1: Simulation angle of repose obtained under different adsorption energies

[0122] Adsorption energy / J m 3 ]] Simulated angle of repose / ° Adsorption energy / J m 3 ]] Simulated angle of repose / ° 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] As shown in Table 1, when the adsorption energy is 0.0035 J / m 3 , the simulation angle of repose is 68.99°, which is closest to the experimental angle of repose of 69.8° of aluminum powder, with an error of 1.16%, and no serious particle agglomeration is observed during the simulation, which is consistent with the actual experimental phenomenon. Therefore, the adsorption energy of 0.0035 J / m 3 is selected for 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 restitution coefficient is set to 0.65, and the sliding friction coefficient is set to 0.5. The simulation angle of repose obtained in Step 2 is 68.99°, which is less than the experimental angle of repose of 69.8°. Starting with the initial value of the rolling friction coefficient of 0.5, gradually increasing the collision restitution coefficient by an adjustment interval of 0.01, a series of angle of repose simulations are carried out, and the simulation angle of repose obtained under each rolling friction coefficient is recorded until the simulation stops when the rolling friction coefficient is 0.6. The simulation of the closest angle of repose to the experimental angle of repose is selected, and the rolling friction coefficient corresponding to the simulation is set as the rolling friction coefficient calibration value.

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

[0127] Step 4.4: Obtain the sliding friction coefficient calibration value:

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

[0129] Step five, the calibrated value of the sliding friction coefficient obtained in step 4.1, the calibrated value of the collision restitution coefficient obtained in step 4.1, the calibrated value of the adsorption energy obtained in step 4.3, and the calibrated value of the rolling friction coefficient obtained in step 4.4 are integrated, i.e., 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 the 35-micron spherical aluminum powder particles are a collision restitution coefficient of 0.65, a sliding friction coefficient of 0.5, a rolling friction coefficient of 0.58, and an adsorption energy of 0.0035 J / m 3 .

[0131] Comparative Example 1

[0132] This comparative example gives a calibration method of the contact parameters of the micron-sized spherical aluminum powder for energetic materials, which is basically the same as that of Embodiment 1, except that in step two, the roughening multiple of the aluminum powder particle size during modeling is different. In this embodiment, the roughening multiple of the aluminum powder particle size during modeling is set to 1-2 times. As the multiple is too small, the calculation period is too long, and the simulation result cannot be obtained.

[0133] Comparative Example 2

[0134] This comparative example gives a calibration method of the contact parameters of the micron-sized spherical aluminum powder for energetic materials, which is basically the same as that of Embodiment 1, except that in step two, the roughening multiple of the aluminum powder particle size during modeling is different. In this embodiment, the roughening multiple of the aluminum powder particle size during modeling is set to 15-20 times. As the multiple is too large, the simulation is distorted, and the effective simulation result cannot be obtained.

Claims

1. A method for calibrating the contact parameters of microsized spherical aluminum powder for energetic materials, characterized in that, The method specifically comprises the following steps: Step one, take the micron-sized spherical aluminum powder and conduct a repose angle experiment to obtain the experimental repose angle of the micron-sized spherical aluminum powder; Step two, based on the discrete element method, a simulation geometry model of the repose angle of the micron-sized spherical aluminum powder is established; Step three, the calibration sequence is determined: The numerical value of the contact parameters of the micron-sized spherical aluminum powder is set to carry out the simulation of the repose angle; the contact parameters of the micron-sized spherical aluminum powder include the collision restitution coefficient, the rolling friction coefficient, the sliding friction coefficient and the adsorption energy between the particles of the micron-sized spherical aluminum powder; If the error between the simulation repose angle and the experimental repose angle obtained in step one is greater than 30%, the calibration sequence is determined as: adsorption energy calibration, collision restitution coefficient calibration, rolling friction coefficient calibration, and sliding friction coefficient calibration; If the error between the simulation repose angle and the experimental repose angle obtained in step one is less than or equal to 30%, the calibration sequence is determined as: collision restitution coefficient calibration, adsorption energy calibration, rolling friction coefficient calibration, and sliding friction coefficient calibration; Step four, the contact parameters are calibrated: According to the sequence determined in step three, the simulation of the repose angle is carried out to obtain the calibration value of the contact parameters of the micron-sized spherical aluminum powder; Step five, the calibration value of the contact parameters obtained in step four is integrated to complete the calibration of the contact parameters of the micron-sized spherical aluminum powder used for energetic materials.

2. The method for calibrating the contact parameter of the microsized spherical aluminum powder for energetic materials according to claim 1, characterized in that, In step two, when modeling, the roughening multiple of the particle size of the micron-sized spherical aluminum powder is 3-10 times.

3. The method for calibrating the contact parameters of the microsized spherical aluminum powder for energetic materials according to claim 1, characterized in that, When the calibration sequence is determined as: adsorption energy calibration, collision restitution coefficient calibration, rolling friction coefficient calibration, and sliding friction coefficient calibration, step four specifically comprises the following steps: Step 4.1, the adsorption energy calibration value is obtained: The restitution coefficient of the collision between the micron-sized spherical aluminum powder particles and the particles is set to e , e =0.5; The rolling friction coefficient is set to If the error between all the simulation repose angles and the experimental repose angle is greater than 0.5% and no serious particle agglomeration phenomenon is observed in the simulation process, the simulation whose simulation repose angle is closest to the experimental repose angle is selected, then the assignment value of the adsorption energy corresponding to this simulation is set as the adsorption energy calibration value, and step 4.2 is continued; , If the error between all the simulation repose angles and the experimental repose angle is greater than 0.5% but the simulation whose simulation repose angle is closest to the experimental repose angle has a serious particle agglomeration phenomenon in the simulation process, the simulation which has no serious particle agglomeration phenomenon and whose simulation repose angle is closest to the experimental repose angle is selected, then the assignment value of the adsorption energy corresponding to this simulation is set as the adsorption energy calibration value, and step 4.2 is continued; = 0.5; the sliding friction coefficient is set to Step 4.2, the collision restitution coefficient calibration value is obtained: , If the error between all the simulation repose angles and the experimental repose angle is greater than 0.5%, the simulation whose simulation repose angle is closest to the experimental repose angle is selected, then the assignment value of the collision restitution coefficient corresponding to this simulation is set as the collision restitution coefficient calibration value, and step 4.3 is continued; = 0.5; With the initial value of adsorption energy Step 4.3, the rolling friction coefficient calibration value is obtained: Starting from 0, If the error between all the simulation repose angles and the experimental repose angle is greater than 0.5%, the simulation whose simulation repose angle is closest to the experimental repose angle is selected, then the assignment value of the collision restitution coefficient corresponding to this simulation is set as the collision restitution coefficient calibration value, and step 4.3 is continued; 0 = 0.0005 J / m 3 ,by ​ By gradually increasing the adjustment interval, the adsorption energy was assigned a value, and a series of repose angle simulations were conducted, with a result of 0.0001 J / m. 3 ≤ ​ ≤0 . 0005 J / m 3 Record the simulated angle of repose obtained at each adsorption energy until the adsorption energy is assigned a value of 0.005 J / m. 3 The simulation should be stopped immediately. ​ ​ If the error between the simulated rest angle and the experimental rest 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, and the collision recovery coefficient calibration value is e， The rolling friction coefficient calibration value is ​ The sliding friction coefficient calibration value is ​ , and step five is directly performed. ​ The adsorption energy between the micron-sized spherical aluminum powder particles is set to the calibration value of the adsorption energy obtained in step 4.1; the rolling friction coefficient is set to ​ , ​ = 0.5; and the sliding friction coefficient is set to ​ , ​ = 0.

5. with the initial value of the restitution coefficient e 0 as the start, e 0 = 0.5, gradually increase or decrease the restitution coefficient with an adjustment interval of 0.01 in the range of [0.4, 0.7] ​ , and carry out a series of rest angle simulation work; 0.01 ≤ ​ ≤ 0.02; record the simulation rest angle obtained under each restitution coefficient; ​ If the error between the simulation rest angle and the experimental rest angle is less than or equal to 0.5%, the collision restitution coefficient corresponding to this simulation is set as the collision restitution coefficient calibration value, and the rolling friction coefficient calibration value is ​ The sliding friction coefficient calibration value is ​ , and step five is directly performed. ​ The adsorption energy between the micron-sized spherical aluminum powder particles is set to the calibration value of the adsorption energy obtained in step 4.1; the collision restitution coefficient is set to the calibration value of the collision restitution coefficient obtained in step 4.2; and the sliding friction coefficient is set to the calibration value of the sliding friction coefficient obtained in step 4.

3. ​ ; with the initial value of the rolling friction coefficient ​ 0 as the start, ​ 0=0.5, if the simulation rest angle obtained in step 4.2 is greater than the experimental rest angle, gradually reduce the assignment of the rolling friction coefficient in the range of [0.3, 0.5] with an adjustment interval of ​ 0.01≤ ​ ≤0.03; record the simulation rest angle obtained under each rolling friction coefficient; If the simulated angle of repose obtained in step 4.2 is smaller than the experimental angle of repose, then within the range of [0.5, 0.6]... ​ The rolling friction coefficient was assigned by gradually increasing the adjustment interval, and a series of repose angle simulations were carried out, 0.01≤ ​ ≤0.03; Record the simulated angle of repose obtained for each rolling friction coefficient; If the error of all the simulated repose angles and the experimental repose angles is greater than 0.5%, select the simulation whose simulated repose angle is closest to the experimental repose angle, and then set the assignment of the rolling friction coefficient corresponding to the simulation as the rolling friction coefficient calibration value, and continue to step 4.

4. If the error between the simulation angle of repose and the experimental angle of repose is less than or equal to 0.5%, the rolling friction coefficient corresponding to this simulation is set as the rolling friction coefficient calibration value, and the sliding friction coefficient calibration value is directly obtained in step five. μ , directly to step five; Step 4.4, obtain the sliding friction coefficient calibration value: Set the collision recovery coefficient between the micron-level spherical aluminum powder particles and the particles as the adsorption energy calibration value obtained in step 4.1; set the collision recovery coefficient as the collision recovery coefficient calibration value obtained in step 4.2; set the rolling friction coefficient as the rolling friction coefficient calibration value obtained in step 4.3; with the initial value of the sliding friction coefficient μ 0 as the starting value, μ 0 = 0.5, if the simulation rest angle obtained in step 4.3 is greater than the experimental rest angle, then gradually reduce the assignment of the sliding friction coefficient in the range of [0.4, 0.5] with an adjustment interval of Δμ 0.02≤ Δμ ≤0.04; record the simulation rest angle obtained under each sliding friction coefficient; If the simulation angle of repose obtained in step 4.3 is less than the experimental angle of repose, gradually increase the assignment of the sliding friction coefficient in the adjustment interval of [0.5, 0.8] to carry out a series of simulation of the angle of repose, 0.02≤ Δμ ≤0.04; record the simulation angle of repose obtained under each sliding friction coefficient; Δμ If the simulation angle of repose obtained in step 4.3 is less than the experimental angle of repose, gradually increase the assignment of the sliding friction coefficient in the adjustment interval of [0.5, 0.8] to carry out a series of simulation of the angle of repose, 0.02≤ Δμ ≤0.04; record the simulation angle of repose obtained under each sliding friction coefficient; Δμ If the simulation angle of repose obtained in step 4.3 is less than the Select the simulation whose simulated repose angle is closest to the experimental repose angle, and then set the assignment of the sliding friction coefficient corresponding to the simulation as the sliding friction coefficient calibration value, and continue to step five.

4. The method for calibration of contact parameters of microsized spherical aluminum powder for energetic materials according to claim 1, characterized in that, When the calibration order is determined as: collision recovery coefficient calibration, adsorption energy calibration, rolling friction coefficient calibration, sliding friction coefficient calibration, the step four specifically comprises the following steps: Step 4.1, obtain the collision recovery coefficient calibration value: The inter-particle adsorption energy of the micron-sized spherical aluminum powder particles is set to Eads , Eads = 0.0005 J / m 3 ; The rolling friction coefficient is set to δ, δ = 0.5; the sliding friction coefficient is set to μ, μ = 0.5; with the initial value of the restitution coefficient e 0 as the start, e 0 = 0.5, gradually increase or decrease the restitution coefficient in the range of [0.4, 0.7] with an adjustment interval of 0.01 Δe 0.01≤ Δe ≤0.02; record the simulation of the rest angle obtained under each restitution coefficient; If the error of all the simulated repose angles and the experimental repose angles is greater than 0.5%, select the simulation whose simulated repose angle is closest to the experimental repose angle, and then set the assignment of the collision recovery coefficient corresponding to the simulation as the collision recovery coefficient calibration value, and continue to step 4.

2. If the error between the simulation rest angle and the experimental rest angle is less than or equal to 0.5%, the collision restitution coefficient corresponding to this simulation is set as the collision restitution coefficient calibration value, and the rolling friction coefficient calibration value is δ, the sliding friction coefficient calibration value is μ , and the adsorption energy calibration value is Eads, Step five is directly performed; Step 4.2, obtain the adsorption energy calibration value: The collision restitution coefficient between the micron-sized spherical aluminum powder particles is set to the collision restitution 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. With the initial value of adsorption energy Eads Starting from 0, Eads 0 = 0.0005 J / m 3 ,by ΔEads By gradually increasing the adjustment interval, the adsorption energy was assigned a value, and a series of repose angle simulations were conducted, with a result of 0.0001 J / m. 3 ≤ ΔEads ≤0 . 0005 J / m 3 Record the simulated angle of repose obtained at each adsorption energy until the adsorption energy is assigned a value of 0.005 J / m. 3 The simulation should be stopped immediately. If the error of all the simulated repose angles and the experimental repose angles is greater than 0.5%, and no serious particle agglomeration phenomenon is observed in the simulation process, select the simulation whose simulated repose angle is closest to the experimental repose angle, and then set the assignment of the adsorption energy corresponding to the simulation as the adsorption energy calibration value, and continue to step 4.

3. If the error of all the simulated repose angles and the experimental repose angles is greater than 0.5%, but the simulation whose simulated repose angle is closest to the experimental repose angle has a serious particle agglomeration phenomenon in the simulation process, select the simulation whose simulated repose angle is closest to the experimental repose angle and has no serious particle agglomeration phenomenon, and then set the assignment of the adsorption energy corresponding to the simulation as the adsorption energy calibration value, and continue to step 4.

3. If the error between the simulation angle of repose and the experimental angle of repose is less than or equal to 0.5%, the adsorption energy value corresponding to this simulation is set as the adsorption energy calibration value, and the rolling friction coefficient calibration value is δ, The sliding friction coefficient calibration value is μ , and step five is directly performed. Step 4.3, obtain the rolling friction coefficient calibration value: The collision restitution coefficient between the micron-sized spherical aluminum powder particles is set to the collision restitution 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 ; with the initial value of the rolling friction coefficient δ 0 as the start, δ 0=0.5, if the simulation rest angle obtained in step 4.2 is greater than the experimental rest angle, gradually reduce the assignment of the rolling friction coefficient in the range of [0.3, 0.5] with an adjustment interval of Δδ 0.01≤ Δδ ≤0.03; record the simulation rest angle obtained under each rolling friction coefficient; If the simulated angle of repose obtained in step 4.2 is smaller than the experimental angle of repose, then within the range of [0.5, 0.6]... Δδ The rolling friction coefficient was assigned by gradually increasing the adjustment interval, and a series of repose angle simulations were carried out, 0.01≤ Δδ ≤0.03; Record the simulated angle of repose obtained for each rolling friction coefficient; If the error of all the simulated repose angles and the experimental repose angles is greater than 0.5%, select the simulation whose simulated repose angle is closest to the experimental repose angle, and then set the assignment of the rolling friction coefficient corresponding to the simulation as the rolling friction coefficient calibration value, and continue to step 4.

4. If the error between the simulation angle of repose and the experimental angle of repose is less than or equal to 0.5%, the rolling friction coefficient corresponding to this simulation is set as the rolling friction coefficient calibration value, and the sliding friction coefficient calibration value is directly obtained in step five. μ , directly to step five; Step 4.4, obtain the sliding friction coefficient calibration value: Set the collision recovery coefficient between the micron-level spherical aluminum powder particles and the particles as the collision recovery coefficient calibration value obtained in step 4.1; set the adsorption energy as the adsorption energy calibration value obtained in step 4.2; set the rolling friction coefficient as the rolling friction coefficient calibration value obtained in step 4.3; with the initial value of the sliding friction coefficient μ 0 as the start, μ 0=0.5, if the simulation rest angle obtained in step 4.3 is greater than the experimental rest angle, gradually reduce the assignment of the sliding friction coefficient in the range of [0.4, 0.5] with an adjustment interval of Δμ 0.02≤ Δμ ≤0.04; record the simulation rest angle obtained under each sliding friction coefficient until the simulation is stopped when the assignment of the sliding friction coefficient is 0.4; If the simulated angle of repose obtained in step 4.3 is smaller than the experimental angle of repose, then within the range of [0.5, 0.8]... Δμ The adjustment interval is gradually increased, and the sliding friction coefficient is assigned a value. A series of repose angle simulations are carried out, 0.02≤ Δμ ≤0.04; Record the simulated angle of repose obtained for each coefficient of sliding friction; Selecting the simulation of the experimental angle of repose closest to the simulation, and then the corresponding sliding friction coefficient of the simulation is set as the sliding friction coefficient calibration value, and the step five is continued.

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

6. The method for calibration of contact parameters of microsized spherical aluminum powder for energetic materials according to claim 1, characterized in that, The step one comprises: weighing a plurality of groups of micron-level spherical aluminum powder with different mass; repeatedly performing the angle of repose experiment for each group of micron-level spherical aluminum powder for several times to obtain a plurality of angle of repose values; and calculating and obtaining the average experimental angle of repose alpha of the plurality of groups of micron-level spherical aluminum powder with different mass, which is the experimental angle of repose of the aluminum powder.

7. The method for calibrating the contact parameters of the microsized spherical aluminum powder for energetic materials according to claim 5, characterized in that, In step one, the angle of repose experiment is repeatedly performed for each group of micron-level spherical aluminum powder for 3-10 times.

8. The method for calibrating the contact parameters of the microsized spherical aluminum powder for energetic materials according to claim 5, characterized in that, In step one, the mass of each group of microsized spherical aluminum powder ranges from 10 g to 100 g, and the average mass of multiple groups of microsized spherical aluminum powder with different masses is W 1.

9. The method for calibrating the contact parameter of the microsized spherical aluminum powder for energetic materials according to claim 8, characterized in that, In step two, the modeling process includes: setting the inter-particle model of the micron-sized spherical aluminum powder particles as the JKR model, generating the W 1 gram of micron-sized spherical aluminum powder particles, obtaining the angle of repose simulation geometric model of the aluminum powder.

10. The method for calibration of contact parameters of microsized spherical aluminum powder for energetic materials according to claim 1, characterized in that, In step three, the coefficient of restitution for collisions between micron-sized spherical aluminum powder particles is set to e 1, 0.4 ≤ e 1 ≤ 0.5; the coefficient of rolling friction is set to δ 1, 0.4 ≤ δ 1 ≤ 0.5; the coefficient of sliding friction is set to μ 1, 0.4 ≤ μ 1 ≤ 0.5; the adsorption energy is set to Eads 1, 0.0005 J / m 3 ≤ Eads 1 ≤ 0.0015 J / m 3 .

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