Boundary-Layer-Tripping Studies of Compressible Dynamic Stall Flow

摘要

The challenging task of properly tripping the boundary layer of a leading-edge-stalling airfoil experiencing compressible dynamic stall at Reynolds numbers between 3.6x10~5 and 8.1xl0~5 has been addressed. Real-time interferometry data of the flow over an oscillating airfoil have been obtained at freestream Much numbers of 0.3 and 0.45. The airfoil was tripped by separately placing five different trips of varying lengths near the leading edge. The trip heights ranged from 40 to 175 deg. . The resulting flow and airfoil performance were evaluated using the criteria of elimination of the laminar separation bubble that otherwise forms, delay of dynamic stall onset to higher angles of attack, and production of consistently higher suction peaks.