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A recursive algorithm has been developed to automatically generate multi-grid meshed wind tunnel wake surveys. Using near-real-time processing of 7-hole probe pressure data to obtain velocity components, the local circulation in the flow was computed and used to determine the grid spacing. This results in a significant reduction in the number of sample stations per survey. Results from a recent test at the 7 by 10 Foot Wind Tunnel at NASA /Ames Research Center are presented.

A wind-tunnel test was conducted for an unswept wing with a half-span Fowler flap. Surface pressures, flow visualization, and wake surveys were obtained for two flap riggings representative of landing configurations. The primary influence of the half-span flap is to create spanwise pressure gradients on the main element and flap. Pressure distributions near the flap tip indicate the presence of two distinct suction peaks on the upper surface. Flow visualization using smoke verifies the existence of two co-rotating vortices near the flap tip that merge before reaching the trailing edge. Seven-hole-probe wake surveys yield values for both profile and induced drag.