PRESSURE-BASED HIGH ORDER TVD METHODOLOGY FOR DYNAMIC STALL CONTROL

THE QUANTITIVE PREDICTION OF THE DYNAMICS OF SEPARATING UNSTEADY FLOWS, SUCH AS DYNAMIC STALL, IS OF CRUCIAL IMPORTANCE. THIS STUDY PROPOSES SEVERAL NEW METHODOLOGIES OF SOLVING 3-D NAVIER-STOKES EQUATIONS WITH PRESSURE-BASED ALGORITHM IN BOTH STATIONARY AND MOVING (BODY-FIXED) COORDINATES. THE PROPOSED PRESSURE-BASED ALGORITHM IS EQUALLY EFFICIENT FOR LOW SPEED INCOMPRESSIBLE AND HIGH SPEED COMPRESSIBLE FLOWS, AND APPLICABLE TO THE LAMINAR AND TURBULENT FLOWS. THE CONVECTIVE TERM DISCRETIZATION BY HIGH-ORDER TVD SCHEME TO BE DEVELOPED REQUIRES NO ARTIFICIAL DISSIPATION, AND CAN PROPERLY RESOLVE THE CONCENTRATION TIP VORTICES WITH MINIMUM NUMERICAL DIFFUSION. PROPOSED NEWTON'S ITERATION TECHNIQUE NOT ONLY CAN INCREASE THE CONVERGENCE RATE BUT ALSO CAN STRONGLY COUPLE THE INTERACTION BETWEEN PRESSURE AND VELOCITIES. THE NOVEL HYPERBOLIZATION OF PRESSURE EQUATION CAN SIGNIFICANTLY INCREASE SOLVER'S EFFICIENCY. THE PROPOSED METHODOLOGIES WILL BE IMPLEMENTED BY ADAPTING AN EXISTING ADVANCED CFD CODE, REFLEQS. IN PHASE I STUDY, THE MODIFIED CODE WILL BE DEMONSTRATED BY SIMULATING DYNAMIC STALL ON AN OSCILLATING THREE-DIMENSIONAL WING-BODY CONFIGURATION IN SUBSONIC FLOW REGIME. FURTHER DEVELOPMENT AND VALIDATION WILL BE CARRIED OUT IN THE PHASE II.