ABSTRACT
The purpose of this work is to optimize the blade design of an axial-flow fan.
Four different chord length and five twisting angle of their blades were studied. The
fan was designed by using NACA 5505 series. The first investigation is conducted to
the blade design in the variation of chord length. The base chord length is constant of
130 mm and the tip is vary from 84, 92, 102 and 110 mm. The second study is in the
variation of twisting angle from 0, 10, 20, 30 and 40o. The performances of the fans
were measured in a Von Mises stress criterion under pressure of 500 Pa. From the
variation of chord length, the shortest length of 84 mm was delivered the lowest
stress. While the variation of twisting angle, the lowest stress is delivered by 40o of
twisting angle. The proposed blade design is presented by using combination of
twisting angle 10, 20, 30 and 40o in single blade model. The blade total length of
446.5 mm is divided into four parts and every part have different twisting angle.
From the stress result, the proposed model was delivered lower stress compared to the
other models.
Keywords: Axial fan, twist angle, chord length, stress analysis, finite element
method.