飞翼布局无人机进排气影响及机理分析

进气道尾喷管的存在不仅影响着飞机机身前后的流场特性与压力分布,而且影响着飞机升力特性、阻力特性以及力矩特性.为了研究进排气效应对飞机气动特性的影响,采用计算流体力学(CFD)数值模拟技术,建立飞翼布局无人机(UAV)堵锥整流模型和动力影响模型,其中动力影响模型是根据发动机不同的工作状态,在进气道以及尾喷管截面上设置不同的边界条件,对比分析这两种计算模型在流场特征和气动特性上的差异性,揭示内在的影响机理.进排气效应的研究有助于飞机/发动机的一体化气动综合设计.

Influence of engine inlet and exhaust on flying wing UAV and its mechanism analysis

The inlet and exhaust can remarkably affect the pressure distribution and flow fields properties near the forebody and afterbody of the aircraft, therefore causing certain changes to the lift, drag and momentum characteristics. In order to know how inlet and exhaust affect aerodynamic characteristics of aircraft, computational fluid dynamics (CFD) numerical simulation technology was introduced to build a flying wing unmanned aerial vehicle (UAV) fairing model and an actual model, in which engine inlet and exhaust were taken into account. Boundary conditions of the actual model at the inlet and exhaust cross sections were set according to the different engine working conditions. Comparative analysis shows differences of flow fields and aerodynamic characteristics between these two models and reveals inner effect mechanism of the differences. The study on exhaust effect benefits the comprehensive aerodynamic design of aircraft/engine integrated system.