Studying the Effect of Geometric Parameters of Axial Fan Twisted Blades inside Different Cross-Sectional Ducts

Abstract

Numerical simulation validated with experimental tests is carried out to study the effects of changing some geometrical parameters concerning the twisted blades of a DC power driven computer-case axial fan having a curved-shape winglet tip including the winglet tip mean bending angle, the winglet tip height and the blade profile leading-edge twisting angle. The winglet tip incidence angle is changed from (90-70) degrees, the blade tip base height is increased by (10) %, and the variation of the blade twisting angle is changed from (35-24) degrees considering the air flow past the rotating fan is isothermal and subsonic, the simulation is performed using the shear stress incorporated K-w turbulence model in the ANSYS-CFX package neglecting the thermal effect considering the flow is passing through rectangular and circular cross-sectional ducts. The results indicated that the fan is more effective using the circular duct regarding that the three investigated parameters have a differential influence on the free stream flow.