Lifetime prediction of a typical rocket combustion chamber by means of viscoplastic damage modeling

The lifetime of a launch vehicle is determined by the cyclic lifetime of its major components. In this regard, the combustion chamber of a rocket engine is one of the most important components of a launch vehicle. It undergoes extreme cyclic thermomechanical loading during its operation. Due to its high thermal conductivity and ductile behavior, the application of copper alloy as the liner material of the cooling channels is well established. However, it is well known that after several engine cycles the wall of the cooling channels becomes thinner and bulges towards the interior of the chamber before crack of the cooling channel wall eventually occurs. This failure mode which limits the lifetime of the thrust chamber is known as the „doghouse“ effect.