外挂组合体对无人直升机气动特性影响分析

为研究某型无人直升机机身两侧的外挂组合体对其气动特性的影响, 采用求解Navier-Stokes方程的方法, 对直升机机身的气动特性进行数值计算, 并与风洞试验结果进行对比, 验证CFD (computational fluid dynamics)计算方法的准确性和可靠性。计算加装外挂组合体前后的无人直升机气动特性, 包括不同侧滑角和不同挂载状态, 并进行对比分析。结果表明, 外挂组合体对无人直升机的阻力影响较大, 对升力和俯仰力矩等影响较小。加装外挂组合体后, 无人直升机气动特性受侧滑角变化的影响更大, 外挂组合体中的导弹数量变化对无人直升机的阻力影响较大。研究结果可为加装外挂组合体的气动布局和减阻设计提供参考。

Analysis of Influence of Combined External Store on Aerodynamic Characteristics of Unmanned Helicopter

In order to analysis the aerodynamic characteristics of unmanned helicopter combined external stores on the both sides of unmanned helicopter fuselage. The aerodynamic characteristics of the helicopter fuselage are calculated by the method which can solve the Navier-Stokes equation, and the results are compared with the results of wind tunnel test to verify the accuracy and reliability of the CFD (computational fluid dynamics) method. The aerodynamic characteristics of unmanned helicopter installing combined external store are calculated in different yaw angles and different loading conditions. The results show that the combined external stores has a large impact on the helicopter drag, and a less impact on the lift and pitch moment and so on. The aerodynamic characteristic of unmanned helicopter is affected larger by the yaw angle after the installation of weapon. The change of missiles number has a relatively large impact on the helicopter drag. The results can provide an reference for aerodynamic layout of combined external stores and the drag reduction design.