Influence of 0°-15° attack angle on aero-optical imaging deviation of a blunt-nose vehicle.

ABSTRACT

A turbulent flow field is created in a vehicle's head during high-speed flight, and this flow field causes the airborne optical system's receiving target images to be displaced, blurred, and jittered. In this study, we examine the impact of a 0°-15° angle of attack on the aero-optical imaging deviation. With the use of modeling and meshing software, we created a model of a conventional blunt-headed vehicle. Computational fluid dynamics calculations were performed using finite element analysis software; the ray equations were solved iteratively by the Runge-Kutta method. Finally, the imaging deviation data were obtained by using reverse ray tracing and tracing stop criteria. The findings demonstrate that, as the angle of attack increases from 0° to 15°, the thickness of the nonuniform flow field above the vehicle flow field cross-section axis gradually increases. As the density of the nonuniform flow field through which light propagates increases, so does the corresponding refractive index and the aero-optical imaging deviation.