关键词: 翼型, 失速, 前缘结节, 流动控制, 流动模式

Abstract:

In recent years， leading-edge serrations as a passive method for wing separation control have attracted significant attention in academia. This paper investigates the influence of two leading-edge tubercles with relatively large-scale wavelengths on the aerodynamics of a full-span wing near critical angles through numerical simulations. Compared to the baseline wing， the stalling process of the two improved wing shapes with larger-scale wavelengths is both slow and stable. By studying the surface flow characteristics through numerical simulations， we found that the wing with serrations having a wavelength of 1.5 times the chord length maintained a singular and regular flow pattern both before and after stalling， while the flow pattern of the wing with a wavelength equal to the chord length transitioned from a singular， regular flow to a more complex combination of multiple flow patterns as the angle increased. A mechanism is proposed to explain this transition in flow patterns， and two flow combination mechanisms are presented to explain the reasons for the different flow patterns.

Key words: airfoil, stall, leading-edge protuberances, flow control, flow pattern