COMPUTATIONAL FLUID DYNAMICS AND FLIGHT TEST INVESTIGATION OF AIRPLANE STALL DYNAMICS WITH WING CONTAMINATION – PHASE I

摘要

A research program is under way torninvestigate factors influencing transportrnairplane stall onset at take off. Methodologiesrnhave been developed to study thernunsteady aerodynamics of dynamic stall forrnboth straight- and swept-wing airplanerntypes. The conditions associated with therntake off maneuver with wing contaminationrnare replicated in flight tests at altitude andrncomplemented by ground runs. A roughnessrnmodel is introduced to simulate arbitraryrnwing contamination. An unsteady Navier-rnStokes analysis using two modifiedrnturbulence models will simulate therncombined effects of roughness, pitch raternand ground proximity. Prediction of thernunsteady flow separation on airplane wingsrnin ground effect will be accomplished byrnanalytically linking the flight test results andrnCFD simulations. CFD results arernpresented for a steady state rough-airfoilrncase and for a clean oscillating airfoil inrnand out of stall. The analytical approach isrnoutlined and results are presented, includingrnflight test data from the first phase, detailsrnof roughness simulation, instrumentationrndiagnostics and CFD validations.