Improved Fringe Imaging Skin Friction Analysis Using Automated Fringe Identification

A method for automating the detection of interference patterns for use with the OilDrop Fringe Imaging Skin Friction (Oil-Drop FISF) technique has been developed and tested. A windowed Fourier transform is used to locate regions likely to contain fringes, and a correlation technique is used to determine the exact locations of fringes within the window . Initial testing of the combined technique has shown promise in that it is able to correctly identify approximately seventy to eighty percent of the interference patterns in several test images.