复合固体推进剂中固体填料的安息角测试与仿真

复合固体推进剂含有固体颗粒较多，离散单元法是一种适合固体推进剂生产过程数值仿真的有效方法，颗粒物料的接触参数是保证离散单元法仿真精度的关键。本文以复合固体推进剂的主要组分铝粉和高氯酸铵固体颗粒为研究对象，通过实验测试获得了相关物料的安息角，利用专业离散元软件EDEM仿真模拟了安息角测试实验过程，建立了物料安息角与接触参数之间的联系。研究表明，滚动摩擦系数和滑动摩擦系数越大，安息角越大，物料流动性越差。对比仿真与实验结果，通过逆向反推法确定了物料的滑动摩擦系数和滚动摩擦系数两个关键接触参数。铝粉与高氯酸铵1∶2混合颗粒的滑动摩擦系数为0.2，滚动摩擦系数为0.05。为固体推进剂加工生产过程离散元数值仿真提供了关键基础数据。

Measurement and simulation of the angle of repose of solid filler in composite solid propellant

The composite solid propellant contains many solid particles. The discrete element method is an effective method suitable for the numerical simulation of the production process of the solid propellant. The contact parameters of the granular materials are the key to ensure the simulation accuracy of the discrete element method. In this paper, the main components of the composite solid propellant (aluminum powder and ammonium perchlorate solid particles) were used as the research materials. The angle of repose of the relevant materials was obtained through experimental measurements. The experimental process of the angle of repose measurement was simulated by using the professional discrete element software EDEM. The relationship between the angle of repose of the materials and the contact parameters has been established. The results have shown that the greater the rolling and sliding friction coefficients, the greater the angle of repose and the poorer the fluidity of the material. By comparing the simulation and experimental results, the two key contact parameters of the rolling and sliding friction coefficients of the materials were determined by the backstepping approach. The sliding friction coefficient and the rolling friction coefficient of the 1∶2 mixture of aluminum powder and ammonium perchlorate were 0.2 and 0.05, respectively. It gives important data support for the discrete element numerical simulation of the production process of solid propellants.