为了提高超声速气动构型的升阻比，减小激波阻力，使用反设计方法结合CFD技术优化Licher双翼，实际算例表明，来流马赫数1．7，无粘情况下只需迭代15步即可得到优化结果，优化后翼型波阻可减小25．5％，升阻比提高30．5％。随后依据翼型目标压力分布这一反设计关键点，分析了非零迎角下翼型各边的受力情况，指出了原目标压力分布的不足，并提出了一种新的阶梯形目标压力分布形式，该方法的优化结果可使升阻比提高49．8％。此外基于NS方程的优化结果表明，原目标压力分布的优化效果被削弱，升阻比仅能提高17％，而新目标压力分布的优化结果受到的影响较小，升阻比仍可提高49．2％，说明在考虑流动粘性特征时，阶梯形目标压力分布形式更具实用价值。%An inverse design method has been applied for the Licher biplane with modern computational fluid dynamics (CFD)technique to increase the lift-drag ratio and reduce the shock wave drag during its the supersonic flight regime.An example of numerical simulation demon-strates that the wave drag can be reduced by 25.5%and the lift-drag ratio rises by 30.5% simul-taneously using this optimization algorithm with inviscid flow assumption as the free stream Mach number is 1.7.In addition,it takes about 15 iterations to get convergent results,which demonstrates that the inverse design method in this paper is efficient.A new stair target pressure distribution,as the key of the inverse design method,has been developed to overcome setbacks of the original one by some analyses of aerodynamic forces.With the new target,the lift-drag ratio can increase up to 49 .8%.Furthermore,the Euler equations in the optimization procedure have been replaced by the Navier-Stokes equations to investigate the influence of viscous fluid.The results indicate that the effect of the optimization with the original target pressure distribution is beyond neg-lect,the lift-drag ratio increases only by 17.0%.However,the results of the new stair target pressure distribution,with more potential practical value,stay almost the same level.
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