Introduction Of Axial Flow Fan

Axial fans with a guide shroud only near the trailing edge of the impeller are widely used in the outdoor unit of split-type room air conditioners. In these systems, in addition to compact structure and large air volume, low noise is a key indicator. However, compared with low-pressure fans for power, this type of low-pressure fan has many different characteristics in structural configuration, design method and internal flow phenomenon, and it is not easy to grasp the low-noise design of the fan and its internal flow mechanism. Domestic and foreign research on noise reduction of this type of fan is mostly carried out by experimental means or some specific methods after blade forming, while research on the performance improvement of air conditioner fan blades by bending and sweeping design is rarely reported.
Based on the conventional quasi-three-dimensional design method of axial flow impeller, the leading edge bending and sweeping technology is adopted, and the CFD/CAD method is used to carry out the coupling design of the axial flow fan of the air conditioner to improve the internal flow condition of the fan at the design point and provide a basis for reducing its noise. The three-dimensional Navier-Stokes equations and Spalart-Allmaras turbulence model are used to calculate and analyze the internal flow of the entire outdoor unit, and the performance of the fan is estimated to reduce the corresponding experimental workload.