This paper deals with the determination of stress distribution for a centrifugal fan consists of back sheet, ten airfoil blades and shroud by using Finite element Packaged program (NSTRAN). The results showed that the blade trailing edge and the shroud plate have amaximum VonMises stress which exceeds the yield point of the materials. Thickness effect of each part on the stress distribution in the impeller was determined with fixing the other parts thickness.The result showed that the optimum thickness of the plate is (11mm), for shroud is (9mm) for blade is (3mm), for back sheet plate is (11mm) for shroud stiffener is (3mm). the overall results pointed out that the shroud plate is a critical part and has a large effect on the stress distribution than other parts.
Keywords: Centrifugal Fan, VonMises stress, Finite Element, NASTRAN