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The purpose of this study is to investigate the two-
dimensional flowfield of the axial fan blade by utilizing the
theories and numerical methods for turbomachine. With the aid of
Vortex-Lattice method, the blade surface is divided into several
panels and each element is described by varying singularity
strength to calculate the velocity and pressure distributions.
The gasdynamic properties of blade are thus computed. In
addition, the influence for various blade geometric parameters
and inflow conditions are studied. The outcomes show that a
large stagger angle results in an increase of blade surface
pressure and a decrease of fan''s overall efficiency. Both the
positive and negative incidence angles would induce the
separation occurred on blade surface. Regards the number of
blade, the lower surface appears backwash easily for a fan with
less number of blade; however, too many blades may obstruct the
flow. Moreover, the rounded leading edge and thin thickness are
suggested to gain a better stability and performance of the fan.
Besides, the maximum thickness of blade should locate in the
vicinity of blade center.
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