Effects of heat treatments to inner liner material, thermal barrier coating, and outer shell material on lifetime of a combustion chamber

Key factors were investigated to extend the lifetime of a combustion chamber of a large thrust rocket engine. Two-dimensional finite element simulations were conducted to estimate creep damage and low cycle fatigue damage to the inner liner of a combustion chamber wall. In these simulations, the effects of difference of heat treatments to the inner liner material, heat shield by a thermal barrier coating, and thermal expansion of the outer shell on lifetime were examined. It was found that heat shield by a thermal barrier coating had the largest effect in extension of the lifetime though the effect depended on the physical characteristic of the inner liner material. Expansion or contraction of the outer liner during combustion affects the restriction of the inner liner resulting in the extension of the lifetime. By combination of these effects, the lifetime can be extended up to about a factor of 10 longer than that of a combustion chamber without any effects. •The properties of the copper alloy of an inner liner strongly affect the lifetime of a chamber wall.•A thermal barrier coating on the surface of the inner liner effectively extends the lifetime.•The outer shell with a low coefficient of thermal expansion can extend the lifetime.•By combination of these effects, the lifetime will be extended about 10 times longer than normal one.