PERFORMANCE OF AN ISOLATED TWO-DIMENSIONAL WEDGE NOZZLE WITH FIXED COWL AND VARIABLE WEDGE CENTERBODY AT MACH NUMBERS UP TO 2.01

摘要

A wind-tunnel investigation has been conducted to determine the aeropropulsion per¬formance (thrust minus drag) of an isolated, two-dimensional wedge nozzle with a simulated variable-wedge mechanism and a fixed cowl. The investigation was conducted statically and at Mach numbers from 0.60 to 1.20 in the Langley 16-foot transonic tunnel and at a Mach number of 2.01 in the Langley 4-foot supersonic pressure tunnel. The ratio of exhaust jet total pressure to free-stream static pressure was varied up to 27 depending on free-stream Mach number. The results indicate that the aeropropulsion performance of the two-dimensional fixed-cowl variable-wedge nozzle is slightly lower (0.7 to 1.4 percent of ideal thrust) than that achieved for a two-dimensional wedge nozzle with a translating shroud, although part of the difference in performance is attributed to internal-performance differ¬ences. The effects of cowl boattail angle, internal expansion area ratio, and wedge half-angle on the performance of the two-dimensional wedge nozzle are discussed.