扇翼飞行器翼型附面层控制数值模拟

基于扇翼飞行器翼型特殊的几何形状及流场特性,在原有翼型的弧形槽下方和后缘加装控制阀门,通过调节阀门开启及开启尺寸的大小,利用弧形槽低压涡所产生的吸力对翼型后缘的附面层进行一定的控制,达到增升减阻的效果。通过采用计算流体力学的方法对其机理及阀门开启尺寸的影响进行了详细计算和分析,研究表明当阀门开启的尺寸为10 mm时,修改翼型的最大升力系数、失速迎角及相同迎角下的升力系数和推力系数均大于基本翼型;随着阀门开启尺寸的增大,修改翼型的最大升力系数和失速迎角均减小,但是在失速前,修改翼型在相同迎角下的升力系数大于基本翼型。此方法可以改变先前通过增大横流风扇的转速来提高其气动性能的做法,减小了能量的消耗,增大了整个飞行器的航程,为扇翼飞行器能够早日投入实际运用奠定了一定的理论基础。

Numerical simulation on boundary layer control method of fanwing aircraft airfoil

Based on the specific geometry of fanwing aircraft airfoil and flow field characteristics, we modify the airfoil by installation of control valves at the trailing edge and below the arc-groove. In order to take advantage of the lower pressure vortex to control the boundary layer of the trailing edge by adjusting the size of valve. CFD method is used to analyze the control method's mechanism and the influence of relative parameter. The calculation results show that when the size of the valve opens to 10 mm, the modified airfoil's maximum lift coefficient and stall angle of attack and the lift and thrust coefficients with the same angle of attack are greater than the basic airfoil. With the increase of the size of valve, the modified airfoil's maximum lift coefficient and stall angle of attack are reduced, but before stalling, the modified airfoil's lift coefficient is larger than the basic airfoil at the same angle of attack. This method gives us a new way to improve fanwing's aerodynamic performance, decrease power consumption and extend the flight range, which lays a certain theoretical foundation for the practical use of the fanwing aircraft as soon as possible.