细长翼分离涡的布涡计算法

 细长翼在迎角稍大时,前缘卷起螺旋状分离涡,使上表面压力降低,升力增加。涡襟翼技术也是利用前缘涡的这一特性提高升阻比的。为计算有分离涡的机翼特性,须研究分离涡层的卷起和涡层之间相互干扰的计算方法。早期Brown和Michael,Smith等在锥形流假设下,应用细长体理论计算过三角翼的气动特性。Sack和尹协远等放弃锥形流假设,用离散涡代替脱体涡层,但仍用保角转绘法处理横流面内绕翼面流动。这类方法对横截面形状较复杂的细长翼（如带涡襟翼的机翼）,因转绘函数复杂,计算困难。本文为避免转绘带来的困难,采用直接布涡法计算有分离涡的机翼气动特性。

A DISCRETE VORTEX METHOD FOR SLENDER WING VORTEX-SHEET COMPUTATION

A discrete vortex method based on the slender body theory is proposed by setting vortex-elements on the wing and point vortices on the free vortex-sheets to simulate the flow pattern of the rolling-up of vortices separated from the leading-and trailing-edges of a slender wing. The method is particularly convenient for complex configurations, because the computation is needed only in the physical plane without the use. of conforrnal mapping as useally done previously. A 74 swept delta wing and its modification equipped with vortex-and apex-flaps were selected to calculate their separated vortex flow patterns. The computational results appears satisfactory in comparison with the experiments.