Wang Xufei, Shi Yongqiang, Yang Qingzhen, Xiang Huimin, Zhang Saile
School of Power and Energy, Northwestern Polytechnical University, Xi'an 710129, China.
Sensors (Basel). 2025 Jul 21;25(14):4525. doi: 10.3390/s25144525.
Aircraft, as electromagnetically complex targets, have radar cross-sections (RCSs) that are influenced by various factors, with the inlet duct being a critical component that often serves as a primary source of electromagnetic scattering, significantly impacting the scattering characteristics. In light of the conflict between aerodynamic performance and electromagnetic characteristics in the design of aircraft engine inlet grilles, this paper proposes a metasurface radar-absorbing inlet grille (RIG) solution based on a NACA symmetric airfoil. The RIG adopts a sandwich structure consisting of a polyethylene terephthalate (PET) dielectric substrate, a copper zigzag metal strip array, and an indium tin oxide (ITO) resistive film. By leveraging the principles of surface plasmon polaritons, electromagnetic wave absorption can be achieved. To enhance the design efficiency, a multi-objective Bayesian optimization framework driven by the expected hypervolume improvement (EHVI) is constructed. The results show that, compared with a conventional rectangular cross-section grille, an airfoil-shaped grille under the same constraints will reduce both aerodynamic losses and the absorption bandwidth. After 100-step EHVI-Bayesian optimization, the optimized balanced model attains a 57.79% reduction in aerodynamic loss relative to the rectangular-shaped grille, while its absorption bandwidth increases by 111.99%. The RCS exhibits a reduction of over 8.77 dBsm in the high-frequency band. These results confirm that the proposed optimization design process can effectively balance the conflict between aerodynamic performance and stealth performance for RIGs, reducing the signal strength of aircraft engine inlets.
飞机作为电磁复杂目标，其雷达散射截面（RCS）受多种因素影响，进气道是关键部件，常作为电磁散射的主要来源，对散射特性有显著影响。鉴于飞机发动机进气格栅设计中空气动力学性能与电磁特性之间的矛盾，本文提出一种基于NACA对称翼型的超表面吸波进气格栅（RIG）解决方案。该RIG采用由聚对苯二甲酸乙二酯（PET）介电基板、铜曲折金属条阵列和氧化铟锡（ITO）电阻膜组成的夹层结构。通过利用表面等离激元极化子原理，可实现电磁波吸收。为提高设计效率，构建了由预期超体积改进（EHVI）驱动的多目标贝叶斯优化框架。结果表明，与传统矩形截面格栅相比，在相同约束条件下，翼型格栅将降低空气动力学损失和吸收带宽。经过100步EHVI - 贝叶斯优化后，优化后的平衡模型相对于矩形格栅的空气动力学损失降低了57.79%，同时其吸收带宽增加了111.99%。在高频带，RCS降低超过8.77 dBsm。这些结果证实，所提出的优化设计过程能够有效平衡RIG的空气动力学性能与隐身性能之间的矛盾，降低飞机发动机进气口的信号强度。
