亚声速翼身融合无人机概念外形参数优化

为了兼顾翼身融合（BWB）布局无人机（UAV）的气动、隐身和结构重量要求，应用优化方法研究了某亚声速翼身融合无人机概念方案的外形设计问题。外形优化设计流程包括全机参数化几何外形模型、气动分析、机翼根部弯矩计算、雷达散射截面（RCS）分析、代理模型的建立和外形参数优化计算。选择了三种不同优化目标研究翼身融合无人机外形优化问题：①未配平状态升阻比最大；②配平状态升阻比最大；③配平状态升阻比尽量大和机翼弯矩尽量小。通过优化结果的对比分析，揭示了配平约束和机翼弯矩目标对优化设计结果的影响。研究结果表明：计入配平约束能够有效提高配平升阻比；将配平状态升阻比尽量大和机翼根部弯矩尽量小作为优化目标能够获得合理的优化外形。

Configuration Optimization of Subsonic Blended Wing Body UAV Conceptual Design

A configuration optimization method for a notional subsonic unmanned aerial vehicle (UAV) with a blended wing body (BWB) is proposed for simultaneous considerations of the requirements of aerodynamics, stealth and structural mass. The process of the configuration optimization consists of parametric configuration modeling, analysis for the aerodynamic characteristics, computation of the wing bending moment, prediction of radar cross section (RCS), creation of the surrogate model and optimization for the configuration parameters. Three cases with different design objectives for the configuration optimization of the blended wing body unmanned aerial vehicle are studied: ① maximization for the lift to drag ratio without the trim constraint; ② maximization for the lift to drag ratio with the trim constraint; and ③ maximization for the lift to drag ratio and minimization for the wing bending moment with the trim constraint. Impacts of the trim constraint and the wing bending moment on the optimal designs are investigated through the comparisons of the optimal results. It concludes that the inclusion of the trim constraint can increase the lift to drag ratio of the unmanned aerial vehicle configuration under the trim condition, and the lift to drag ratio and wing bending moment should be simultaneously considered as the design objectives to obtain a practicaloptimal configuration of the blended wing body unmanned aerial vehicle.