| While flying in the air, the aircraft harass the air and form a plane wave with unsteady velocity, which form a pair of eddy that rotate reversely after the aircraft. It is the eddy that form the aircraft wake vortex. According to the record of NTSB, there are 130 accidents in the USA that caused by aircraft wake voetex. Thus, detection of aircraft wake vortex becomes a key problem on aircraft safety especially on airdrome safety.Aimming at radar detection of aircraft wake vortex, the article analysis hydrodynamics and electromagnetic character of wake vortex, and then it properly assume that numerical simulation of aircraft wake vortex is a solution of passive conservative parameters,which fully describe the evolution of aircraft wake vortex with time and spacing distribution in stable state. Upwind difference method with non-uniform grid spacing is used to solve Passive Conservative parameters. Then, the evolution of RCS in aircraft wake vortex, which changes with time and frequency, is obtained. Finally, the article use OpenGL to construct aircraft wake vortex simulation platform, which show the evolution of aircraft wake vortex vividly.The work of the article is divided into three parts:Firstly, the article establish passive conservative model of aircraft wake vortex, and it present diffuse-convection equation of the passive conservative model, which was solved by one order upwind difference method to obtain two-dimensional distributive gray image of aircraft wake vortex. Then, the article use high order upwind difference format to solve diffuse-convection equation and compare results in different order condition. Finally, aimming at un-uniform grid spacing technology used in solving passive conservative simulation of aircraft wake vortex, the article validate the correctness and superiority of un-uniform grid spacing technology in solving passive conservative simulation and present proper un-uniform grid spacing measure.Secondly, the article deduce RCS model of aircraft wake vortex, which present the relationship between RCS and passive conservative parameters. Then, the article analysis RCS character of C5-A which change with time, frequency and direction. Finally, the article present doppler spectrum and validate correctness of doppler spectrum.Finally, the article present system structure and simulation flow of the wake vortex simulation platform. According to the result of hydrodynamics and electromagnetic analysis, the platform construct hydrodynamics and electromagnetic scatter module and use OpenGL to construct three-dimensional simulation platform, which present evolution of the aircraft wake vortex vividly. |
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