A Multi-disciplinary Tool for Space Launch Systems Propulsion Analysis

An accurate predictive capability of coupled fluid-structure interaction in propulsion system is crucial in the development of NASA's new Space Launch System (SLS). This STTR effort will develop a multi-disciplinary tool to improve CFD prediction capability in modeling coupled fluid structure interaction (FSI) phenomena for many SLS propulsion applications such as flexible inhibitors for SRMs. During Phase I, an Application Programming Interface (API) framework with conservative interface treatment will be developed to couple a NASA production CFD solver with a DoD open source nonlinear large deformation Finite Element solver developed by the proposing firm. The multi-disciplinary tool will be rigorously validated against coupled as well as decoupled problems (fluid and structure individually). Phase I will demonstrate the improved pressure oscillation modeling fidelity and provide great insight into the physics of nonlinear FSI leading to thrust oscillations in SRMs. The Phase II effort will conduct more validations and investigations of several SLS FSI phenomena including the physics of flexible inhibitors in triggering unsteady pressure oscillations and flow induced vibration of turbine and inducer blades in liquid rocket engines.