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风挡雨刷在飞行过程中易出现被气流吹离复位位置、飘起现象,阻碍飞行员视野,严重影响飞行安全。选取某型机风挡雨刷作为优化对象,采用了结构、非结构混合网格的办法,在机身壁面附近生成结构化网格,在雨刷机构表面生成非结构化网格,用Interface面将两部分结合生成雨刷最终计算模型。利用Fluent软件,基于N-S方程和S-A湍流模型,采用时间平均法对不可压缩流的参数进行时均化,计算了不同飞行状态下,风挡雨刷在复位位置以不同角度停放及增加扰流板时所受气动力,对风挡雨刷的外形及停放角度进行优化,比较分析了优化前后雨刷所受气动力。仿真计算结果表明,雨刷合理的停放角度、在刷臂上加装扰流板能有效引导风挡雨刷迎风面气流的方向,从而减小雨刷迎风面所受气动力。通过试飞验证了数值计算的可靠性及优化方案的可行性,为风挡雨刷预紧力的设置及复位位置的确定提供依据。
Windshield wipers prone to being blown away from the reset position during the flight, floating phenomenon, hinder the pilot’s vision, seriously affecting flight safety. Select a type of windshield wipers as the optimization object, the use of structured, unstructured hybrid grid approach to generate a structured grid near the fuselage wall, the surface of the wiper mechanism to generate unstructured grid with Interface will be two parts Combined with the resulting wiper final calculation model. Using Fluent software, based on Navier-Stokes equations and SA turbulence model, the time-averaged method was used to time-average the parameters of the incompressible flow. When the windscreen wipers were parked at different angles and the spoiler was added under different flight conditions By aerodynamic force, the windshield wiper shape and parking angle optimization, comparative analysis of the wiper force before and after optimization. The simulation results show that the proper parking angle of the wiper can effectively guide the direction of the airflow on the windward side of the windshield wiper, thus reducing the aerodynamic force on the windward side of the wiper. Through the test flight, the reliability of numerical calculation and the feasibility of the optimization scheme were verified, which provided the basis for the setting of the windscreen wiper preload and the determination of the reset position.