Dynamic Coupled Thermoelasticity Equations in Analysis of Solid Rocket Motor Shells

Excessive heat transfer causes major defects on the rocket motors. For example, it will reduce mechanical properties of materials or causes melting of internal wall layers when temperature rises. In the other hand, non-uniform distribution of temperature in solid propellant motor shells, in addition to thermal stresses will develop mechanical stresses. Calculating the temperature distribution and thermal and mechanical stresses on the solid rocket motors were interested by the designers. In this paper, the manner of calculating the mechanical and thermal wall stresses on solid propellant rocket motors using dynamic coupled thermoelasticity equations relationships are presented. For this purpose, firstly differential equations governing the issue are resolved using the finite element method. The presented approach is applied and tested on a real rocket and the effect of thermal insulation in wall temperatures and mechanical stresses is shown.