Study of aerodynamic uncertainty on the complex slender vehicle at high angle of attack

Abstract

The phenomenon of lateral aerodynamic uncertainty is discovered in the wind tunnel test on the slender vehicle at high angle of attack. To analyze the mechanism of the phenomenon, the numerical simulation method with random pulsation added in the free stream is used, and the aerodynamic uncertainty of the vehicle under the wind tunnel test condition is reproduced by the simulation. The analysis of the flow field leads us to a conclusion that the mechanism of aerodynamic uncertainty is the asymmetry separation, which has a high sensitivity to the disturbance of the flow around the missle. The uncertainty with respect to the angle of attack for a “+” configuration of the main wing is given and the difference of the uncertainty between the “+” and “×” configurations are then analyzed. At last, the action of pulling up through the high angle of attack and the process of temporary atmospheric turbulence are simulated to study the effect of the real flight environment rather than the wind tunnel condition to the aerodynamic uncertainty. Based on these results, it can be concluded that the uncertainty is not looked upon as quite severe in real flight environment as that in the wind tunnel condition, and the maneuverability of flight can be controlled.