Cross flow fan
Cross flow fan consists of motor, impeller(wheel) and housing. The impeller is produced a whole by the plastic injection or the aluminum alloy pressure casting, including multi-leaf, long cylindrical with forward multi-wing blades.
Its operating principle as follows:
When the impeller rotates, the airflow enters the cascade from the open end of the impeller, passing through the interior of the impeller, and is discharged into the volute from the other side of the cascade to form a working airflow. The flow of the airflow in the impeller is complex, while the speed field of the airflow is unsteady. There is a vortex in the impeller, centered near the volute tongue. The existence of the vortex causes a circulating flow at the output end of the impeller. Outside the vortex, the flow line of the airflow in the impeller is arc-shaped. Therefore, the flow velocity at each point on the outer circumference of the impeller is inconsistent. The closer to the vortex core, the greater the velocity, and the closer to the volute, the smaller the velocity. The airflow speed and pressure at the fan outlet are not uniform, so the flow and pressure coefficient of the fan are average. The position of the vortex has a great influence on the performance of the cross-flow fan. The center of the vortex is close to the inner circumference of the impeller and close to the volute tongue. The performance of the fan is good. While the center of the vortex is far away from the vortex, the area of the circulating flow is increased, so efficiency of the fan is reduced.