TITLE:
Design of a Three-Dimensional Centrifugal Fan with Controlled Blade Loading Approach
AUTHORS:
Jin Xiong, Xin Ai, Kaibin Wang, Jingyin Li
KEYWORDS:
Centrifugal Fan, Controlled Angular Momentum, High Flow-Rate
JOURNAL NAME:
Open Journal of Fluid Dynamics,
Vol.7 No.3,
September
28,
2017
ABSTRACT: The high flow-rate centrifugal fan needs a three-dimensional impeller to achieve
a high efficiency. In this paper, the design procedure of a high-efficiency
three-dimensional centrifugal fan is presented. First, the main dimensions of the
fan were calculated by using the conventional one-dimensional method. Then,
the blade loading or the angular momentum distribution along the meridional
streamline on the blade surfaces is prescribed. After that, the three-dimensional
blade is determined by using the streamline curvature method. With the aid of
numerical simulations, the performance of the three-dimensional fan was improved
and some of the key influence factors were investigated. The analyses
indicate that, as to the high flow-rate centrifugal fan, the Stanitz modified formula
is recommended to calculate the separation radius, rb. A proper increase in
the separation radius is beneficial for the fan’s performance. It is also indicated
that a decrease in the angular momentum on the hub leads to an increase in total
pressure efficiency, under the condition of a given constant mean angular
momentum at the outlet of the blade. In addition, the installation of a fairing on
the hub plate can improve the fan’s efficiency evidently when the streamline
curvature method is adopted to design the three-dimensional impeller.