Simulation of Fluid Structure Interaction in Overexpanded Cold Gas Rocket Nozzles using the DLR TAU Code

Abstract

During the transient startup and shutdown process of a rocket engine high side loads occur, due to unsymmetrical flow patterns. The resulting deformation, and its retroactive effect onto the internal flow, may excite the nozzle structure and can lead to its fatal damage. Flow separation at the nozzle wall amplifies the deformation. To investigate and predict the effects and the underlying mechanisms a simulation environment, coupling the DLR TAU code to the structural analysis tool MSC Nastran, was used to simulate the flow structure interaction and its scalability in sub-scale cold gas rocket engine nozzles.