Design and optimization of low detectable wing structure based on LHM

Low detectable wing structure can meet the aerodynamic, structure and stealth requirement of aircraft wing, but when it is applied to the wing with limited space, its stealth effect is restricted because of its structural characteristics. In order to solve this problem, left-handed material (LHM) is added in the traditional stealth structure in this paper. Firstly, from the viewpoint of stealth design, a typical LHM is selected to study its electromagnetic property by using the backward absorption rate which is calculated from its radar cross section (RCS) at different incidence angles. Then the LHM is used in the wing stealth structure according to its electromagnetic property. With the same RCS reduction effect, the application of LHM can effectively reduce the volume of the stealth structure. Finally, to further enhance the RCS reduction effect, a sandwich low detectable wing structure with LHM is put forward and the structure parameters are optimized by the surrogate model. The results show that the optimal structure RCS is reduced by 15 dB compared to the RCS of metal wing; it is reduced by more than 10 dB compared to the same wing structure without LHM.