鸭式布局机翼非线性气动力计算的一种简化方法

本文提出了一种计算鸭式布局机翼非线性气动力的简化方法，通过引入鸭翼的当量集中涡概念，使计算模型得到简化，大幅度地减少了计算量，加快了收敛速度，算例结果表明：本文方法计算结果与实验是吻合的。

A Simplified Method for Simulating Steady, Unsteady Flow around Canard-Wing Configuration

Much experimental work has been done about canard-wing configurationsin the last quarter century. But canard-wing configuration computations wereconsidered only in a few papers 10, 12], and were limited to steady flow. In computations,the convergence speed of the free vortex position decreases,and the computational time increases exponentially with increasing number ofthe divided elements. For unsteady flow, there are more segments on the freevortex sheet; so, the computational time becomes even much larger, and theconvergence becomes slower. The present paper is believed to be a goodbeginning to remedy the situation. In this paper, a simplified method is presented to calculate the steady, orunsteady flow around the canard-wing configurations. An improved unsteadyNonlinear Vortex Lattice Method is used to simulate the wing, and the canardand its free vortex sheet are modelled with an equivalent concentrated vortex.In present method, the position of the equivalent concentrated vortex in theflow field is determined simultaneously with the position of the free vortexsheet shed from the wing, In computation, the needed initial point of theposition of the equivalent concentrated vortex is selected quite nicely andeasily with a rule suggested in this paper. Through numerical examples, it isshown that effect of interference, improving or aggravating the aerodynamicloads on the wing, depends on the span station of the canard concentratedvortex to a great extent. The aerodynamic loads for the canard-wing configura-tions calculated by the present method agree well with the experiments orother more complicated methods. The idea of introducing an equivalentconcentrated vortex is believed to be the principal contribution of this paper. It is believed that this idea will find application in many problems inaerodynamics which involve interference.