STRUCTURAL ANALYSIS OF THE CYCLIC LOADING OF REGENERATIVELY COOLED COMBUSTION CHAMBER WALLS USING 2D AND 3D FINITE ELEMENT MODELS

Kurzfassung

A coupled thermal and structural 3d quasi stationary Finite Element (FEM) analysis of a typical rocket combustion chamber wall during a full cycle including pre cooling, hot run, post cooling and relaxation is presented. The results of this 3d analysis are compared with the results of 2d plane strain and 2d generalized plane strain analyses. Finally, a post-processing method is applied in order to estimate the combustion chamber life time. This life time estimation method takes into account the standard Low Cycle Fatigue part as well as additional parts – accounting for the quasi static (or ratcheting) fatigue and the thermal degradation of the chamber wall material.