A cross-flow fan is a fluid that cross-flow fan through the fan impeller twice, the fluid flows in the radial direction and then flows out in the radial direction. The intake and exhaust directions are in the same plane, and the exhaust body is evenly distributed along the width of the cross-flow fan. Because of its simple structure, small size, and high dynamic pressure coefficient, it can reach a long distance. It is widely used in laser instruments, air conditioners, air curtain equipment, dryers, hairdryers, household appliances, and grain combine harvesters.