亚音速升力面气动敏感性导数计算

 具有任意曲线前缘的亚音速升力面的气动敏感性导数由核函数法给出。用自适应积分法计算弦向积分,用Multhopp法结合抽去奇点,计算Mangler积分主值。将积分核展成Chebyshef多项式的渐近展开式以保证结果的收敛性。最后将广义力系数及其敏感性导数表示成简单形式,对椭圆、矩形和后掠机翼作了计算,所得结果在升力面理论精度范围内与直接由核函数法得到的结果一致;而且所得到的偏导数可在飞机设计中分析综合用于多学科优化。

AERODYNAMIC SENSITIVITIES FOR SUBSONIC LIFTING-SURFACE

Aerodynamic sensitivity for subsonic lifting-surface with arbitrary curved leading edge is evaluated by kernal function method. The chordwise integration is carried out by an adaptive quadrature algorithm. Mangier principal value integral is calculated by Multropp method combined with subtracting points of singularity. The kernal of Mangier integral is expanded into an asymptotic expansion of chebyshef polynomials in order to assure the convergence of results. The expression of generalized force coefficients and the corresponding sensitivity derivatives are derived into very concise forms by means of an appropriate series representation for load distribution and the calculation of upwash velocity in Trefftz plane. Illustrative calculations for elliptic, rectangular and sweptback wings show that the force coefficient result of sensitivity derivative method are actually identical with that of direct kernal function method within the accuracy of lifting-surface theory, but the partial derivatives obtained hereby can be used for multidisciplinary optimization by decomposition for aircraft design.