不同飞行速度下的共轴式直升机气动特性研究

Research on Aerodynamic Characteristics of Coaxial Helicopter at Different Flight Speed

近年来,共轴式直升机飞行速度越来越快,其气动特性也与常规直升机有比较大的差异。采用求解N-S方程的方法对某共轴式直升机算例样机的气动特性进行了数值计算,计算状态包括五种典型的飞行速度。通过分析全机和桨毂等部件的气动特性计算结果发现,在目前直升机的最高飞行速度范围内,共轴式直升机气动特性受飞行速度的影响比较小。未来随着直升机飞行速度进一步提高,全机和桨毂的阻力增长很快,同时全机和垂尾的偏航力矩变化比较大。研究结果对直升机减阻设计和气动布局选型有重要参考。

In recent years,the coaxial helicopter can fly faster and faster. Compared with the conventional helicopter,their aerodynamic characteristic has relatively large differences. The method of solving N-S equation was adopted to calculate the aerodynamic characteristics of one coaxial configuration helicopter. The calculation state included five typical flight speeds. By analyzing the calculation results of the whole helicopter and each component,it was found that within the maximum flight speed range of current existing helicopters,the aerodynamic characteristics of the coaxial helicopter were less affected by the flight speed. With the further increase of helicopter flight speed,the drag of whole helicopter and rotor hub increased rapidly,and the yaw moment of whole helicopter and vertical tail changes largely. The research results had important reference for the drag reduction design and pneumatic layout selection of new configuration or high speed helicopter.