Comparisons of Unsteady Flow Fields About Straight and Swept Wings Using Flow Visualization and Hotwire Anemometry.

摘要

The three-dimensional, spatial and temporal unsteady flow characteristics induced by dynamic sinusoidal oscillations of different sweep geometry finite wings were investigated. The span-dependent, finite wing flow interactions between unsteady wingtip and leading edge vortical structures were documented for three sweep configurations (30 deg forward, zero, and 30 deg aft) using flow visualization and hotwire anemometry techniques. The three dimensional flow field about the wings was investigated by recording flow visualization and hotwire data at numerous span locations from wingtip to wingroot. Hotwire velocity data was collected across the chordlength of each wing from leading to trailing edge. The hotwire data confirmed hypotheses formulated during flow visualization analyses and added quantifying magnitude information. All data recorded during these tests illustrated highly repeatable unsteady flow patterns which indicate promising beneficial aerodynamic flow characteristics when compared to static test at identical geometries. Keywords: Hot wire anemometers; Three dimensional flow; aerodynamic characteristics; Swept wings; Wing tip vortices. (EDC)