HIGH-FIDELITY SIMULATION OF TURBOFAN NOISE BROADBAND FAN NOISE CLOSELY TIED TO TURBULENT FLOW ON AND AROUND…

Public award description

HIGH-FIDELITY SIMULATION OF TURBOFAN NOISE BROADBAND FAN NOISE CLOSELY TIED TO TURBULENT FLOW ON AND AROUND THE FAN BLADES REPRESENTS A KEY CHALLENGE TO THE NOISE REDUCTION COMMUNITY DUE TO THE INTERACTION OF A HIGHLY TURBULENT FLOW FIELD WITH COMPLEX, MOVING GEOMETRIES. PREDICTION AND HIGH-FIDELITY SIMULATION OF FAN NOISE DEMANDS A FUNDAMENTAL INNOVATION IN CFD METHODS DUE TO MOVING GEOMETRIES AND ACCURACY REQUIREMENTS. THE OBJECTIVE THIS WORK IS TO DEVELOP A FLEXIBLE APPROACH TO HANDLING MULTIPLE, OVERSET GRIDS FOR USE IN SIMULATIONS OF TURBOMACHINERY. IN PHASE 1 WE WILL DEVELOP AN INNOVATIVE COMPUTATIONAL SOFTWARE TOOL FOR EFFICIENTLY MANAGING MULTIPLE, OVERLAPPING STRUCTURED MESHES IN RELATIVE MOTION. THIS APPLICATION WILL BE USED CONCURRENTLY WITH A COMPRESSIBLE NAVIER-STOKES SOLVER AND IS AN ENABLING TECHNOLOGY IN ENABLING HIGH-FIDELITY SIMULATIONS OF TURBULENT FLOWS IN COMPLEX, MOVING GEOMETRIES. PHASE 1 WILL DEMONSTRATE SOFTWARE FEASIBILITY USING A SIMPLIFIED MODEL OF THE NASA GLENN SOURCE DIAGNOSTIC TEST (SDT) FAN AT REALISTIC TAKE-OFF CONDITIONS. WE PROPOSE A SIMULATION THAT INCLUDES A MOVING "ROTOR" BLADE ROW ADJACENT TO A STATIC BLADE ROW. TAILORED POST-PROCESSING OF SIMULATION RESULTS WILL PROVIDE INFORMATION ON THE TURBULENT FLOW AND IMPLIED TURBULENT NOISE SOURCES INCLUDING UNSTEADY BLADE SURFACE PRESSURES, ACOUSTIC MODES, AND OVERALL RADIATED NOISE. IN PHASE 2 WE FOCUS PRIMARILY ON BROADBAND TURBULENT NOISE SOURCES OF MODERN TURBOFAN ENGINES. BY UTILIZING A REALISTIC NASA SDT FAN GEOMETRY AND TAKE-OFF FLOW CONDITIONS, WE WILL USE OUR NEW TOOLS TO SIMULATE REAL-WORLD SYSTEMS AND COMMERCIALIZE OUR SOFTWARE PRODUCT.