Lateral Forces on a Slender Body and Their Alleviation at High Incidence

Abstract

A method for alleviation and control of the side force and yawing moment appearing on slender bodies at high angles of attack in symmetrical flight conditions is presented. The effect on lateral forces and moments is achieved by using small, symmetrical jet injection from the nose of the body. Experimental investigation includes the effects of Mach number, Reynolds number, transition strips, and injection rate. Visualization tests are used to demonstrate the effects of jet injection. The results indicate that the injection affects both the stabilization of the separation pattern close to the body and the vortex formation and stability downstream. Alleviation of side forces and yawing moments is achieved at high angles of attack over a large range of subsonic and also transonic speeds. This method can be used also for lateral control at the high angle of attack flight conditions.