Microblowing for High-Angle-of-Attack Vortex Flow Control on a Fighter Aircraft

Abstract

Effectiveness of the microblowing technique for controlling forebody vortex asymmetry at high angles of attack has been investigated in low-speed wind-tunnel experiments with the F-15E fighter aircraft configuration. One blowing-port installation, based on previous experiments with generic forebody shapes, was evaluated. At very high angles of attack (a > 50 deg), microblowing was effective in generating and controlling yawing moment levels comparable to those demonstrated by high-pressure jet nozzle blowing, while requiring only 1/100 as much mass flow, demonstrating the leveraging available through controlling the vortex flowfield at the point of instability. The microblowing port configuration employed was unable to generate usable yawing moments at moderate angles of attack (α≤35 deg). Control-port optimization promises to improve microblowing effectiveness in the intermediate α range