Surface Flow Visualization Tests on Swept Back Wing Configuration Subjected to Subsonic Flow

Abstract

For this investigation swept-back configuration of the wing has been studied experimentally utilizing the surface flow visualization method. Swept-back wings have been widely implemented to achieve high aerodynamic efficiency under high-speed operation. To understand flow structure over wing the pattern formed by surface flow visualization techniques over wing leeward surface has been well implemented in aerodynamic literature. However, it is desirable to investigate the flow structure formed over swept-back wing under low-speed operation. In this study, an experimental study was conducted using surface flow visualization technique upon swept-back, tapered wing configuration. The wing has aspect ratio of 4 and designed using RAE2822 airfoil configuration. Changes in flow pattern with change in angle of attack have mainly been studied. Oil flow visualization studies showed increase in heavy span-wise flow with an increase in angle of incidence. At low-speed operation, the formation of separation bubble over the airfoil and induced span-wise flow from the presence of sweep and taper create three-dimensional vortex flow structure over the wing.