Experimental Characterization of Smooth Body Flow Separation Over Wall-Mounted Gaussian Bump

This study was motivated by the need for a benchmark data set for the characterization of smooth body separation over a wall-mounted, Gaussian surface. Skin friction values were computed using a modified oil film interferometry technique that implements a flexible calibration board to correct for perspective and geometric distortions. Experiments were conducted at the University of Notre Dame to show how this method can be used to acquire skin friction values for models with surface curvature. Two test cases conducted at = 2 × 10⁶ and 4 × 10⁶ were investigated. Image data was processed to determine the centerspan streamwise development of the wall shear stress. The results were compared to a spanwise-periodic direct numerical computation at = 2 × 10⁶ to show the method’s effectiveness.