影响NEPE推进剂药柱结构完整性主要参数的分析

Analysis on Main Parameters Influencing the Structural Integrality of NEPE Solid Propellant Grains

为研究某型NEPE推进剂药柱受温度、内压及过载等载荷联合作用下的结构完整性,基于近似不可压三维热粘弹性有限元法,建立了发动机药柱的三维有限元计算模型。针对NEPE推进剂的力学特性,采用最大应变能准则给出了不同工作温度下药柱结构的安全系数,讨论了松弛模量与泊松比两种材料参数对药柱结构完整性的影响。结果表明,工作温度较高时药柱结构的安全系数较低,适当降低推进剂的松弛模量或增大泊松比可提高药柱结构的完整性。

To analyze structural integrality of NEPE propellant under working load, a finite element model of solid propellant grain was build based on 3D near-incompressible viscoelastic finite element method, under temperature loading, inner pressure and inertia load. Aiming at mechanical performances of NEPE propellant, structural safety factor of grain was calculated under different working temperatures utilizing the rule of maximum strain energy, and the material parameters of relaxation modulus and passion＇s rate influencing the structural integrality of grain were discussed. The results show that the structural safety factor of grain is poorer under relatively higher working temperature, and it will be help for improving the structural integrality of grain when deducing relaxation modulus or using higher passion^s rate of propellant.