Hinge Moment Characterization of All Movable Control Surface

Abstract

AbstractA special side wall mounted test set up rig was designed and realized for hinge moment characterization of an all movable control surface. Experiments were conducted on a 1:2 scale down model of the control surface. In the experiment, two different configurations (A & B) were tested. In configuration A, the control surface is mounted on its actuator cover whereas in the configuration B, the control surface without actuator cover is tested. In case of configuration B, a boundary layer bypass plate was used between tunnel test section side wall and the control surface. The test Mach numbers are 2.0, 2.5, 3.0, and 3.5. The control surface was deflected from −10° to 25° during the test using electrical stepper motor. Integral strain gauge force balance has been used to measure the forces and moment on the control surface. Test data have been analyzed. Normal force co-efficient, hinge moment co-efficient, and variation of center of pressure have been presented in this paper. Hinge moment is significantly influenced by the presence of actuator cover, and it is found higher compared to configuration B. Center of pressure is ahead of the hinge line toward the leading edge of the control surface for both the configurations. The hinge moment is unstable for both the configurations. However, it is more unstable in case of configuration A. KeywordsControl effectivenessCenter of pressureHinge momentUnstable hinge moment