The Optimization Design Of The Wing With Low Detectable Structure

Stealth performance is an important viability index of modern fighter. The application of shaping and material stealth-technology is important measure. However, the individual shaping stealth or material stealth technology can not taking into account the aircraft's flight performance and the impact on their surrounding environment, so a stealth structure that combine both the technologies to solve this problem will become another important way. Stealth structure,considering the complex surface shapes and positions of the low detectable aircraft, consists of non-metallic structural materials and absorbing materials, wave-transparent materials and other materials.In this thesis, the research on the wing with stealth structure is carried out. Aircraft stealth structure and the analysis of its radar scattering characteristics are complex. Scattering properties of v arious stealth structures are analyzed with the method of moment, the calculate results shows that the stealth structure has better stealth characteristics. As the size of the leading edge absorbing structures have significant impact on the wing's RCS, it is necessary to optimize the stealth structure of the leading edge. In this thesis those structures are optimized using surrogate model which mainly includes experiment design and approximation approaches. The results of numerical simulation and optimization are helpful for stealth structures design and other structures.At the last chapter of this thesis, an electromagnetic simulation software,CST MWS,is introduced;and the scattering field of plane wave from the wing structures, filled with non-uniform anisotropic plasma in leading edge, is evaluated by employing the software.The dependences of the scattering properties on the parameters of both the incident wave and the plasma are obtained with the plane wave incidence. The results show the wing structure with closed-plasma stealthy technique has good RCS properties.