复合固体推进剂颗粒脱湿损伤参数反演

Parameters Inversion of Particle Dewetting

关键词:  固体推进剂  细观力学  界面损伤  数值模拟  参数反演

Key words:  Solid propellant  Mesomechanics  Interfacial damage  Numerical simulation  Parameters inversion

摘要:

为确定复合固体推进剂颗粒脱湿损伤参数，采用分子动力学方法建立了复合固体推进剂颗粒夹杂模型，根据Surface-based cohesive方法，在高氯酸铵(AP)颗粒与基体之间的界面处设置接触损伤，对复合固体推进剂的细观损伤过程进行数值仿真计算。将数值仿真得到的应力-应变曲线与试验曲线进行对比，建立颗粒脱湿损伤参数的优化目标函数，通过分步迭代计算，对颗粒脱湿损伤参数进行反演识别。结果表明:根据反演参数计算复合固体推进剂细观损伤过程，颗粒夹杂模型表现出的宏观应力-应变关系与试验结果吻合良好，说明双折线损伤模型可以近似表征复合固体推进剂的脱湿损伤。

Abstract:

In order to obtain particle dewetting damage parameters of composite solid propellants，a particle packing model of the composite solid propellant was created by molecular dynamics method. The surface-based cohesive approach was adopted to set the interfacial damage between ammonium perchlorate (AP) particles and the binder. Meco-damage process of the composite solid propellant was computed by numerical simulation method. Stress-strain curves obtained from numerical simulations were compared with the test results. The optimization target function of particle dewetting damage parameters was established，and the parameters were inverted by the step iterative method. The results show that stress-strain curves of the packing model based on the inversion parameters was in good agreement with the test results. It illustrated that the conduplicate-line damage model can exactly describe the dewetting damage process of the composite solid propellant.