Structure Design And Optimization Approach For Low RCS Screws

Abstract

With the rapid development of radar stealth and detection technology, large numbers of screws and rivets have become a major factor that affecting the aircraft’s invisibility. This is because these components have a significant impact on the overall radar cross section of the aircraft, when the electromagnetic scattering characteristic of strong scattering sources is greatly reduced. By analyzing the scattering contribution of the head and body to the screw, it has been obtained that the geometric structure of the head plays a primary role in influencing the overall radar cross section of the screw. According to the scattering mechanism and stealth principle, a shape design method for the low RCS screw is proposed, and then we investigated the scattering characteristic of the octagonal, hexadecagonal, and circular head screws respectively. Furthermore, a structure optimization approach for low RCS screws is introduced which takes the angle of the incident wave into account. This has resulted in the development of a corresponding triangular screw with low detection capabilities. The simulation results show that within the operating frequency band of radar, the triangular head screw has a maximum RCS reduction of approximately 30.1dB compared to a traditional round head screw in [-90°,90°]. On average, there is a reduction of 12.6dB. The simulated results demonstrate the effectiveness and feasibility of the proposed design and optimization method for low RCS screw structures