Investigation of the flow structure over a nonslender delta wing : effect of yaw angle

Abstract

Paper presented at the 7th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Turkey, 19-21 July, 2010.

In the present work, vortical flow structure of a delta wing of low sweep angle (A=40") was investigated both qualitatively and quantitatively using dye visualization and stereoscopic Particle Image Velicimetry (sPIV) technique. Firstly, the leading edge vortex formation is observed using the dye visualization technique by varying angle of attack within the range of 7°≤α≤17° and yaw angle 00≤θ≤150°. Secondly, changes in flow structure were observed by varying the yaw angle of the delta wing within the range of 0°≤θ≤ 15° for the angle of attack of α=10°. The dye visualization experiments were conducted for investigating the flow structure over the wing qualitatively in the plan-view plane. From PIV experiments, patterns of time­-averaged vorticity, <ω>, streamline, <'¥> distribution of velocity vectors,<V> and transverse, <v>/U and streamwise, <u>/U velocity components and Reynolds stress correlations, <u'v'>/U2 for various angles of attack and yaw angles were obtained in order to reveal the flow mechanism in plan-view plane adjacent to the surface of the wing.