Experimental And Simulation Study On Mechanical Properties Of Granular Propellants

The study of the mechanical properties of propellant is of great significance to the safe launch of weapons.This paper adopts the method of combining the experiment and simulation to study the quasi-static mechanical properties and dynamic impact mechanical properties of granular propellants at room temperature.The following main conclusions are obtained from the experimental and simulation results:The results of quasi-static compression of single-hole granular propellant particles are basically consistent with the simulation results of Ansys finite element simulation.The experimental results show that the single-hole granular propellant particles have the characteristic of transformation from elastoplastic to linear elastoplastic at room temperature,and different compression rates have little influence on the elastic modulus of the propellant particles,while the strength limit will rise with the increasing of the compression rate.The simulation results show that the stress is concentrated in the middle of the pores of the granular propellant particles,so that the propellant particles present a deformation of “drum shape” in the quasi-quantity static compression experiment.The results of drop impact test of single-hole granular propellant prove that the stress and strain curves of single-hole granular propellant exhibit different characteristics at different impact rates,namely showing obvious linear elastic behavior at low impact rate and showing power-hardening characteristics at high impact rate.The simulation results are basically consistent with the experimental results.The simulation results of the single-hole granular propellant during the impact process show that the stress inside the propellant is transmitted in the form of waves during the impact process,and the stress waves in the middle are superimposed,so that the single-hole granular propellant particles are the bulging deformationoccurred under the impact.The axial deformation of the propellant can be reduced by increasing the elastic modulus and impact stress of the propellant.Based on the simulation of single-hole granular propellant,the impact simulation of the seven-hole granular propellant particles is carried out.The simulation results show that the inner stress and strain of the seven-hole granular propellant is similar to Impact process of single-pore granular propellant.The increase of the hole numbers has little effect on the transfer process of the internal stress of the propellant.