Introduction To Axial Flow Fan Machine

Axial flow fans with flow conduits only near the tail edge of the impeller are widely used in outdoor units of split room air conditioners. In these systems, in addition to the compact structure and large air volume, low noise is a key indicator. However, compared with low-pressure fans for power, this low-pressure fan has many different characteristics in structural configuration, design method and inflow phenomenon, and it is not easy to grasp the low-noise design of the fan and its inflow mechanism. Research on noise reduction of such fans at home and abroad mostly uses experimental methods or some specific methods after blade forming, while studies on the bending design of air-conditioning fan blades to achieve their performance improvement is rarely reported.
Based on the conventional quasi-three-dimensional design method of axial flow impeller, the leading edge bending technology is used to design the axial flow fan of the air conditioner by using the CFD/CAD method to improve the inflow condition of the fan at the design point and provide a basis for reducing its noise. The three-dimensional Navig-Stokes equation and the Spalart-Allmaras turbulence model were used to calculate and analyze the entire outdoor unit inflow, and the performance of the fan was estimated to reduce the corresponding experimental workload .