THE INNOVATION PROPOSED HERE IS A HIGH PERFORMANCE, HIGH FIDELITY SIMULATION CAPABILITY TO ENABLE ACCURATE,…

Public award description

THE INNOVATION PROPOSED HERE IS A HIGH PERFORMANCE, HIGH FIDELITY SIMULATION CAPABILITY TO ENABLE ACCURATE, FAST AND ROBUST SIMULATION OF COUPLED CAVITATION AND FLUID-STRUCTURE INTERACTION (FSI) IN FLOWS INVOLVING CRYOGENIC FLUIDS OF INTEREST TO NASA (SUCH AS LOX, LH2, LN2, ETC.). CAVITATION AND OTHER UNSTEADY FLOW-INDUCED PHENOMENA IN SOME COMPONENTS OF LIQUID ROCKET ENGINES AS WELL AS TESTING CAN INDUCE NOT ONLY HIGH-CYCLE FATIGUE BUT ALSO STRUCTURAL FAILURE, AND POSSIBLY EXTENSIVE DAMAGES TO THESE COMPONENTS. THE KEY FEATURES OF THE PROPOSED WORK ARE: (A) ACCURATE AND EFFICIENT UNSTEADY CRYOGENIC CAVITATION SIMULATION METHODOLOGY, AND (B) A ROBUST FIRST PRINCIPLES BASED FLUID-STRUCTURE INTERACTION (FSI) CAPABILITY. ADDITIONALLY, AN OVERSET GRID METHODOLOGY TO SUPPORT OVERLAPPING GRIDS AND HOLE-CUTTING FOR SIMULATING RELATIVE MOTION OF VALVE AND PIPE COMPONENTS WILL BE DEVELOPED ALONG WITH A ROBUST GRID DEFORMATION METHODOLOGY TO MODEL RELATIVE MOTION TO PREDICT THE VIBRATION AND NOISE DURING THE OPERATION OF VALVES FOR CRYOGENIC FLUIDS. THESE METHODOLOGIES WILL BE TIGHTLY COUPLED WITHIN THE FRAMEWORK OF THE LOCI-STREAM CODE WHICH IS A COMPUTATIONAL FLUID DYNAMICS SOLVER ALREADY IN USE AT NASA FOR A VARIETY OF APPLICATIONS. TO SUMMARIZE: THE PROPOSED WORK WILL UPGRADE THE CURRENT CAVITATION MODELS IN LOCI-STREAM, IMPROVE THE NUMERICS OF THE SOLUTION ALGORITHM FROM AN EFFICIENCY POINT OF VIEW, IMPROVE THE COUPLING OF THE CAVITATION MODELS AND THE FSI MODULE WITH LOCI-STREAM, AND WILL RESULT IN AN ACCURATE AND ROBUST PREDICTIVE CAPABILITY TO MODEL THE TRANSIENT FLUID STRUCTURE INTERACTION BETWEEN CRYOGENIC FLUIDS AND IMMERSED COMPONENTS TO PREDICT THE DYNAMIC LOADS, FREQUENCY RESPONSE OF FACILITIES AND TO SUBSTANTIALLY REDUCE THE COSTS OF NASA'S TEST AND LAUNCH OPERATIONS.