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通过求解二维可压Navier-Stokes方程,研究了NACA0012翼型加装微型后缘增升装置(miniTED)后的跨声速流场特性,与Gurney flap(GF)对比分析了几何参数对mini-TED后方涡系及翼型气动特性的影响.将mini-TED的几何细节参数定义为弦向长度和有效高度,两者方向正交.在相同迎角下仅改变miniTED的弦向长度,后缘涡系结构虽发生变化,但翼型气动力几乎没有影响;反之仅改变有效高度则后缘涡系和翼型气动力系数同时发生明显改变,且与同等高度下的GF气动系数相近.结果表明:有效高度是影响翼型气动特性的决定因素.有效高度改变了mini-TED后涡系的发生范围,而相对于整个翼型绕流,后缘涡系的大小是影响翼型流场最重要的因素,而涡系的微观结构和形态的改变影响相对很小.加装mini-TED后上表面激波位置后移、下表面激波强度削弱,从而翼型表面压力分布特性发生了改变.随有效高度增大,mini-TED诱导的涡系发生区域随之增大,引流作用增强,翼型升力系数、阻力系数和低头力矩系数提高,同时相同迎角下翼型的升阻比明显提高.
By solving two-dimensional compressible Navier-Stokes equation, the transonic flow field characteristics of NACA0012 airfoil with microTED lifting device (miniTED) were studied. Compared with Gurney flap (GF), the geometric parameters of mini-TED Rear vortex system and airfoil aerodynamic characteristics of the mini-TED geometric details of the parameters defined as the chord length and effective height, both orthogonal direction.At the same angle of attack only to change the chord length of the miniTED, trailing edge eddy Although the structure changes, but the airfoil aerofoil has almost no effect; the contrary only to change the effective height of the trailing vortex and airfoil aerodynamic coefficients significantly changed at the same time, and with the same height under the GF aerodynamic coefficient similar results show: The effective height is the determinant of the aerodynamic characteristics of the airfoil.The effective height changes the occurrence range of the vortex system after the mini-TED, and the size of the trailing edge vortex is the most important one affecting the airfoil flow field Factor, and the change of microstructure and morphology of the vortex system is relatively small.When mini-TED is installed, the shock of the upper surface is shifted backward and the shock strength of the lower surface is weakened, so the pressure distribution on the surface of the airfoil changes. Effective height increase , Mini-TED induced vortex generation region increases, enhancing the drainage effect, the airfoil lift coefficient, drag coefficient, and the coefficient bow torque increase, while significantly improving the airfoil lift to drag ratio at the same angle of attack.