基于数值模拟的有限翼展吹气控制研究

Numerical simulation of blowing control based on limited wingspan model

以大攻角下增加升力、减小阻力为目的,采用计算流体力学方法,针对在有限展长的三维机翼模型上进行的局部开口吹气控制进行了数值研究。利用结构网格及相应的非定常流计算方法对吹气流动控制进行了数值仿真,分析了吹气动量系数、吹气位置等参数(重点研究吹气口展向位置)对气动特性的影响。研究表明:应用吹气技术可获得较好的气动特性,且能延迟边界层的分离;当吹气动量系数为0.000216且吹气口位于0.2c～0.205c时,二维模型升力系数增加8.2%,阻力系数减小17.2%;当开口长度是有限三维模型翼展的1/5、吹气动量系数为0.003,并在z为2.1～2.4m处引入吹气控制时,三维模型的升力系数增加22.6%,升阻比增加9.5%;对于本文的三维有限翼展机翼模型,当吹气口位于z为2.1～2.4m时可以获得最好的控制效果。

In this paper, active control technologies are studied to increase the lift and reduce the resistance at high angles of attack by means of computational fluid dynamics. Some numerical simulations on blowing control have been promoted by structured grid, unsteady calculation methods and 3D wing model with local blowing. It is also analyzed how the blowing parameters and locations would affect the aerodynamic characteristics, especially on the spanwise position effect to the aerodynamic characteristics. The research results show that blowing can obtain better aerodynamic characteristic and delay the separation of boundary layer. When the Ci=0.000216 and the chord position of blowing located on the 0.2c～0.205 c, the lift coefficient of 2D model increases by 8.2% and drag coefficient decreases by 17.2%. The lift coefficient increases by 22.6% and the lift-to-drag ratio increases by 9.5%, when the span of the blowing is one fifth of the wing when the Ci=0.003 and the spanwise position of blowing locates on the z=2.1～2.4m. The best control effect of 3D model can be achieved when the blowing control locates on the z=2.1～2.4m of the span.