IMPELLER BLADE FOR AXIAL FLOW FAN HAVING COUNTER-ROTATING IMPELLERS

Method for determining the camber line and thickness distribution for blades used in a cooling fan with counter-rotating impellers. The camber lines and thickness distributions for the blades of each of the impellers are determined through use of Bezier curves and chosen to reduce boundary layer separation of airflow across the blades. The Bezier control points are altered to produce a set of distributions of the camber lines and thickness distributions, and the most favorable set is found with increased cooling efficiency.