不同后掠角三角翼的静态地面效应数值模拟

采用数值模拟的方法研究了不同后掠角三角翼的静态地面效应,通过对气动力和流场特性的分析发现,随着后掠角的减小,地面对迎风面下流动的阻滞作用增强,地效导致的迎风面气动力增量也随之增大。地效导致的背风面气动力增量同样随着后掠角的减小而增大,但在不同的后掠角范围内,地效诱导背风面气动力增量的机理不同：中大后掠角下,其主要通过增强前缘涡强度诱导更大的吸力,而小后掠角下,其主要通过促进前缘涡向内扩散增大吸力范围。

Numerical simulation to static ground effect of delta wings with different sweep angles

In this paper, the static ground effect of delta wings with different sweep angles is investigated by numerical simulation. The analyses of aerodynamic force and flow field characteristics show that in ground effect, the "block effect" of ground enhances the windward surface pressure; with the sweep angle decreasing, the "block effect" will be further strengthened, and thus the windward surface aerodynamic force increments due to ground effect increase. Besides, the leeward surface aerodynamic force increments due to ground effect also increase with the sweep angle decreasing, but flow physics is not the same for different sweep angles:for medium and high sweep angles, the leeward surface aerodynamic force increments due to ground effect are attributed to the increase of the suction induced by the enhanced leading edge vortex; for low sweep angles, they are attributed to the suction area extension, which results from the movement of the dispersive leading edge vortex.