초록
Air flow and its pressure at electric fan according to three, four and five blades are analyzed in this study. As the number of blades increases at the same condition of specification, air tends to converge and becomes natural wind but higher power is consumed. And the velocity of wind is decreased as the space between winds becomes narrow. The turbulent flow is happened in the center of the body of revolution and the kinetic energy becomes largest in case of three blades. The pressure is decreased than atmospheric pressure from fan to outlet. As the number of blades increases, the pressure drop becomes smaller and is smallest in case of the fan with three blades. As the study result, The electric fan with three blades is thought to be effective in view of power consumption and design.