超声速导弹弹头热应力的有限元分析

Finite Element Analysis of Thermal Stress of Supersonic Missile Warhead

摘要: 超声速导弹飞行时面临严重的气动加热，弹头的热应力分析对其安全性至关重要。本文设计了导弹弹头的几何结构，采用四面体单元对其进行离散；考虑了SiC陶瓷材料性能随温度变化的影响，以4.3 Ma飞行环境的气动热为边界条件，建立了其热应力数学模型，进行了温度场与应力场的计算分析。结果表明，超声速弹头的气动热对结构的应力影响较大，驻点温度快速升高导致局部应力集中。本文研究结果可为超声速弹头的结构设计提供理论和数据参考。

Abstract: The supersonic missile is faced with severe aerodynamic heating in flight, and the thermal stress analysis of the warhead is very important for its safety. In this paper, the geometric structure of missile warhead is designed, the tetrahedral element is used to discretize, and the material prop-erties of SiC ceramic varying with temperature is considered. The aerodynamic heat of environment when flighting at the speed of 4.3 Ma is used as the boundary condition. The thermal stress mathematical model is established, and the temperature field and stress field are calculated and analyzed. The results show that the aerodynamic heat of supersonic warhead has great influence on the stress and deformation of the structure. And the rapid rise of stagnation point temperature leads to the local stress concentration. This study can provide theoretical and data reference for the structural design of supersonic warhead.