考虑NEPE推进剂力学性能拉压不对称性的装药结构完整性分析
Structural integrity assessment of NEPE propellant grain considering the tension-compression asymmetry of propellant mechanical property
周东谟 1韩王申 1钟山伟 1陈航 1吴晗旭 1刘向阳2
作者信息
- 1. 中北大学 机电工程学院,太原 030051
- 2. 北京理工大学 宇航学院,北京 100081
- 折叠
摘要
为研究NEPE推进剂拉压不对称性对其装药结构完整性的影响,构建了考虑拉压不对称性的推进剂含损伤非线性本构模型,提出一种考虑拉压不对称性的装药结构完整性评估方法,并对轴向和横向联合过载作用下NEPE推进剂药柱进行了结构完整性分析.结果表明:在轴向和横向联合过载作用下,NEPE推进剂药柱处于拉压共存状态,且药柱的拉伸和压缩区域与推进剂本构模型无关;推进剂的拉压不对称性对其力学响应有一定的影响,考虑拉压不对称性的最大等效应变为1.54,介于分别由拉伸本构计算得到的应变 0.193 和压缩本构计算得到的应变 0.100 之间.考虑拉压不对称性的安全系数为5.68,大于未考虑时的安全系数1.73 和4.98,传统的结构完整性评估方法较为保守.
Abstract
In order to investigate the effect of tension-compression asymmetry of propellant mechanical properties on the structural integrity of Nitrate Ester Plasticized Polyether(NEPE)propellant grain,the unified constitutive equations under tension-compression was established,a method for grain structural integrity assessment considering tension-compression asymmetry was proposed and the structural integrity of NEPE propellant grain under the combined axial and transverse overloads was evaluated.The results indicate that the mechanical state of the NEPE propellant grain is in the coexistence of tension and compression under the combined axial and transverse overloads,and the tension and compression regions in propellant grain is independent of the propellant constitutive behavior;the tension-compression asymmetry of the propellant mechanical properties has a certain impact on its mechanical response.The maximum equivalent strain considering the tension-compression asymmetry is 1.54,which is between the strain calculated from the tension constitutive equation of 0.193 and the strain calculated from the compression constitutive equation of 0.100,respectively.Considering the tension-compression asymmetry,the safety factor is 5.68,which is larger than the safety factor of 1.73 and 4.98 when not considered.The traditional method of structural integrity assessment is conservative.
关键词
NEPE推进剂/拉压不对称/结构完整性/过载/力学响应Key words
NEPE propellant/tension-compression asymmetry/structural integrity/overloads/mechanical response引用本文复制引用
出版年
2024
NETL
NSTL
万方数据