The coupling thermal and mechanical effect on submerged nozzles is important in the design of modern rockets upon thermal loading and aerodynamic pressure. In this paper, a simulation with the subroutine of nonuniform pressure and nonuniform heat transfer coefficient was conducted to study the thermo-structural response of a submerged nozzle at the pressure 6 MPa and stagnation temperature 3200 K. Both the aerodynamic parameters and heat coefficients were obtained through analyzing the flow field. It was found that the thermal loading had an important influence on the stress of throat insert for the solid rocket motor (SRM). The hoop stress increases at first and then decreases with the increase of time for the throat insert. The ground hot firing test of SRM with a submerged nozzle was carried out. The experimental results showed that the structural integrity of the submerged nozzle is very normal during SRM operation. The present method is reasonable, which can be applied to study the thermo-structural response of submerged nozzle for SRM.

中文翻译：

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固体火箭发动机热力和机械耦合对水下喷嘴影响的数值模拟

浸入式喷嘴上的热力和机械效应耦合对现代火箭在热负荷和空气动力压力下的设计很重要。本文用压力不均匀和传热系数不均匀的子程序进行了模拟，研究了浸入式喷嘴在6 MPa压力和3200 K停滞温度下的热结构响应。获得了空气动力学参数和热系数通过分析流场。研究发现，热负荷对固体火箭发动机（SRM）的喉管插件应力有重要影响。环向应力首先增加，然后随着喉部插入件时间的增加而减小。使用浸没式喷嘴对SRM进行了地面热烧制测试。实验结果表明，在SRM操作过程中，浸入式喷嘴的结构完整性非常正常。该方法是合理的，可用于研究SRM浸入式水口的热结构响应。