Pola Aliran Hilir Kipas Aksial Pada Variasi Kelengkungan Sudu Dan Sudut Serang

The velocity field downstream of an axial fan was measured using probe 55 P 51 of a Hot Wire Anemometer. The investigation was focused on the mean velocity in axial, tangential and radial directions. Cambered blade of the axial fan was varied in radii of the circle arc at 53, 83 and 113 mm at various angles of attack at 5, 10, 15 and 20o, while it was operated at constant speed of 475 RPM. The measurement was conducted at position Z/D 0.181, 0.310, 0.440, and 0.569. Integral properties of the flow such as torque, thrust, volume rate, and swirling were computed based on flux of axial and angular momentum from the measured profiles at nearest position of the measurement. The performance of the axial fart was determined by comparing those values. The spread of the flow was also calculated as a consideration to determine the performance of the axial fan. Results indicated that operating the axial fan for 53 min radii of circle arc of blade at 150 of angle of attack, has the highest values of torque, thrust, volume rate and radial spread of the flow. In investigation at angle of attack 100, those values decreased from 53.83 to 113 mm. It could be shown also that swirling does not change linearly with respect to the angle of attack. The variation of radii of circle arc of blade and angle of attack at smaller swirl number gave higher spread of the flow. Key words : velocity field downstream axial flow fan, angle of attack, radii of circle arc