Wing tip vortex structure behind an airfoil with flaps at the tip  

作　　者：YANG Ke XU ShengJin 

机构地区：[1]School of Aerospace, Tsinghua University, Beijing 100084, China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2011年第4期743-747,共5页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant No. 10642002)

摘　　要：In this work, the wing tip vortex structure behind a NACA 0015 airfoil with and without small flaps was studied using a Partical Image Velocimetry （PIV） system. The experiment was carried out in a low speed wind tunnel with a test section of 0.5 m x 0.5 m. The Reynolds number （Re）, defined by the chord length of the wing （C）, was 8.1 x 104. The angle of attack was fixed at 10~. The PIV measurements were made from 0 to 2C, measured from the trailing edge of the model. The dihedral angle of three flaps was -15~, 0~ and 15~, respectively. Compared with the clean airfoil, the one with three flaps significantly changed the wing tip vortex structure, the vorticity and the core of the wing tip vortex. The occurrence of three flaps decreased the gradient of pressure on the two sides of the wing tip, which depressed wing tip vortex formation to some extent. Vortices shed from three flaps influence the evolution of the wingtip vortex generated by the base airfoil. The interaction of those vortices resulted in a weakening of the wing tip vortex.In this work,the wing tip vortex structure behind a NACA 0015 airfoil with and without small flaps was studied using a Partical Image Velocimetry (PIV) system.The experiment was carried out in a low speed wind tunnel with a test section of 0.5 m × 0.5 m.The Reynolds number (Re),defined by the chord length of the wing (C),was 8.1×10 4.The angle of attack was fixed at 10°.The PIV measurements were made from 0 to 2C,measured from the trailing edge of the model.The dihedral angle of three flaps was 15°,0° and 15°,respectively.Compared with the clean airfoil,the one with three flaps significantly changed the wing tip vortex structure,the vorticity and the core of the wing tip vortex.The occurrence of three flaps decreased the gradient of pressure on the two sides of the wing tip,which depressed wing tip vortex formation to some extent.Vortices shed from three flaps influence the evolution of the wingtip vortex generated by the base airfoil.The interaction of those vortices resulted in a weakening of the wing tip vortex.

关 键 词：wing tip vortex FLAP PIV 

分 类 号：O357.1[理学—流体力学] V224.5[理学—力学]