抄録
In this paper, an example of combination of flow visualization technique and digital image processing technique is reported. Three dimensional laminar separation on a surface of a circular cone is visualized by oil film method. Oil film pattern on a photograph is divided into a matrix consisting of 256 lines with 256 addressable positions per line. 256 brightness lebels can be assigned to each pixel. A unique program is developed to determine the locations of separation and contour lines by means of brightness distribution of the photograph.