Study of riblet drag reduction for an infinite span wing with different sweep angles

• 作者: Yufei ZHANG Chongyang YAN Haixin CHEN Yuhui YIN
• 来源期刊: 中国航空学报（英文版）
• 年，卷（期）: 2020,（12）
• 所属期刊栏目: Fluid Mechanics and Flight Mechanics
• 页码范围: 3125-3137
• 页数: 13页
• 语种: 英文

摘要

This paper studies the riblet drag reduction effect for an infinite swept wing under a low Reynolds number using a large-eddy simulation. The results show that the drag reduction ratio is not linear under different sweep angles. The maximum drag reduction ratio in this study is 9.5％for a wing with a 45° sweep angle. The local surface streamline angle and turbulence quantities are cal-culated to analyze the drag reduction mechanism. The results demonstrate that the riblets consid-erably suppress the Reynolds stresses above the wing upper surface, while the turbulence kinetic energy in the near wake is increased. A possible relaminarization phenomenon is observed at the middle part of the wing. Quasi-two-dimensional flow structures are observed near the wall, and a peak frequency is considered as the dominant frequency of the region.