地面效应下的不同翼型亚声速气动特性分析

采用数值方法研究了亚声速地面效应条件下不同翼型的气动特性,进一步以Ma=0.5来流工况为例,研究了翼型参数和飞行高度对气动特性的影响。计算结果表明在Ma为0.5、迎角为6°的地效情况下,翼型弯度减小,更容易在翼型前缘产生激波阻力;翼型下翼面后缘弯度增大使得后缘压力更高,升力系数和低头力矩相应增大;随着飞行高度的减小,地效作用加强,翼型下翼面压力增大,下翼面的升力增量大于上翼面吸力损失,机翼升力系数和升阻比增加越来越显著。

Aerodynamic Characteristics of Different Airfoil in Subsonic Flow with Ground Effect

Numerical methods are used to study the aerodynamic characteristics of different airfoils in ground effect at subsonic velocity. Taking Ma as 0.5 as the flow condition, the effects of airfoil parameters and flight height on aerodynamic characteristics are studied. The calculation results show that in the case of ground effect with Ma of 0.5 and angle of attack of 6°, reducing the airfoil curvature is easier to generate shock wave drag at the leading edge of the airfoil. Increasing the trailing edge curvature of the lower surface will increase the pressure on the trailing edge, the lift coefficient and the nose down pitching moment increase accordingly. As the flying height decreases, the ground effect enhances, the pressure on the lower surface of the airfoil increases, and the lift increase on the lower surface is greater than the suction loss on the upper surface. The wing lift coefficient and lift-to-drag ratio increase more and more significantly.