低雷诺数下小型无人机翼型气动特性分析

Aerodynamic Characteristics Analysis of the Small Unmanned Aerial Vehicle’s Airfoil at Low Reynolds Numbers

摘要:

以小型无人机翼型研究为背景,利用基于线性稳定性理论的 eN方法对对小型无人机常用的翼型 CLARKY在雷诺数 Re =1.0×105、5×105、1.0×106,迎角由 -5°~20°时的气动性能进行了计算和对比分析。随着雷诺数的增大,翼型上表面的转捩位置不断向前缘移动,气流分离则由完全分离逐渐转变为层流分离泡结构,使得翼型的最大升力系数和临界迎角增大,阻力减小,最大升阻比显著增大,有利迎角逐渐减小,翼型 CLARKY的气动特性逐渐得到 改善。

Abstract:

Based on the research of small UAV, numerical simulations of the flow over airfoil CLARKY Re =1.0×105、5× 105、1.0×106 were used to analyze the aerodynamic performances -5°~20° in a range of low Reynolds numbers with the transition model eN of linear stability theory. The results showed that the airflow separation was gradually transformed intoa laminar separation bubble structure from completely separation, while the transition position on the upper surface of theairfoil was moved toward leading edge continuously with the increase of Reynolds number, and the aerodynamic character.istics of airfoil CLARKY was gradually improved.