Abstract
Many air conditioners use fan systems for heat exchange. Vibratory motion and noise in the air conditioner occur when the aerodynamic force of the rotating fan blades act on the cabinet of the air conditioner. On the other hand, reaction force corresponding to the aerodynamic force occurs, and then the reaction force transmitted to the motor-feet. Finally, these transmitted forces excite support-structure of the motor. We calculated the aerodynamic force and pressure fluctuation on fan blades by CFD software "PHOENICS" and we also calculated the reaction force, using the results of CFD analysis. Based on the calculation result of pressure fluctuation on fan blade, we proposed the improved blade shape. Finally, we demonstrated that the proposed fan blade show good characteristics of the reaction force.
