EFFECT OF A SIMULATED ENGINE JET BLOWING ABOVE AN ARROW WING AT MACH 2.0

摘要

An investigation of the effects of a gas jet simulating a turbojet engine exhaust blowing above a cambered and twisted arrow wing has been conducted in the Langley 4-foot supersonic pressure tunnel at a Mach number of 2.0. Nozzle pressure ratios from 1 (jet off) to as high as 64 were tested with both helium and air used as jet gases. The tests were conducted at angles of attack from -2° to 8° at a Reynolds number of 9.84 x 106 per meter. Only the forces and moments on the wing were measured. The results of the investigation indicated that the jet blowing over the wing caused reductions in maximum, lift-drag ratio (L/D)max of about 4 percent for helium and 6 percent for air at their respective design nozzle pressure ratios, relative to jet-off data. Moderate changes in the longitudinal, vertical, or angular positions of the jet relative to the wing had little effect on the wing aerodynamic characteristics.