边条/鸭翼对前掠翼和后掠翼气动特性的影响

Effect of strake and canard on aerodynamic characteristics of forward-swept wing and back-swept wing

为分析前掠翼气动布局设计在航空工业中无法得到推广运用的原因,将前掠翼和后掠翼通过加装边条和鸭翼形成简化的边条翼布局、鸭式布局和边条/鸭式布局,从而深入认识前掠翼和后掠翼两种不同布局之间的流动特点以及涡系干扰机理。首先进行算例数值计算,通过对比分析计算结果与试验数据,验证了数值计算方法的可靠性和准确性;然后对不同布局进行数值计算,得到各布局的升力系数曲线;最后通过压力分布云图和流线图对各布局中复杂涡系的干扰机理进行分析。结果表明:基于后掠机翼形成的边条翼布局、鸭式布局和边条/鸭式布局中的涡系之间通过诱导和卷绕作用,涡系相互增强,大幅提高了布局的升力系数并推迟失速迎角,同时加装边条和鸭翼效果更加明显;基于前掠机翼形成的边条翼布局、鸭式布局和边条/鸭式布局中的涡系之间不存在卷绕作用,涡系之间存在碰撞挤压的不利干扰,这使得前掠翼布局在大迎角时的升力系数远远低于相应的后掠翼布局。前掠翼气动布局中的机翼前缘涡在大迎角时无法同鸭翼涡和边条涡相互耦合增强,不能充分地利用非线性升力,这是前掠翼气动布局设计中的一些不足。

In order to analyze the reasons why the design of forward-swept wing aerodynamic configuration cannot be popularized and applied in aviation industry,simplified strake-wing,canard-wing and strake/canard-wing configurations were constituted by fixing strake and canard on forward-swept wing and back-swept wing,so as to deeply understand the flow characteristics and the mechanism of vortices interference between the two different configurations of forward-swept wing and back-swept wing. and First,the reliability and accuracy of numerical computation method were validated by comparing the computing results with experimental data of a standard model. Then,the lift coefficient curves of different configurations were obtained through numerical computation. Finally,the complex vortex interaction mechanism of different configurations were analyzed by pressure contours and streamlines. The results indicate that induction and convolution between vortexes of configurations based on back-swept wing enhance the lift coefficient and increase stalling angle of attack,and the effect was more apparent on the configuration fixed with strake and canard. There is no convolution effect between vortices of configurations based on forward-swept wing,and vortexes of configurations based on forward-swept wing perform an adverse interaction by bumping and squeezing,which makes the lift coefficient of the forward-swept wing much lower than that of the back-swept wing at high angles of attack. The leading-edge vortices of the forward-swept wing cannot be coupled with the canard wing vortices and strake vortices at high angles of attack,and cannot make full use of the non-linear lift force,which is the shortcoming in the aerodynamic layout design of the forward-swept wing.