Multi-blades centrifugal fan and group design method thereof

Abstract

The invention discloses a multi-blades centrifugal fan and a group design method thereof. The multi-blades centrifugal fan comprises a volute shell, a blade wheel and a volute tongue arranged in the volute shell, and a collecting ring arranged on the side of the volute shell. The blade wheel comprises a wheel disc, a wheel cap, and a blade. The blade is double circular arc form, and an inlet incidence angel beta 1of the blade is 75 degrees-90 degrees, an outlet incidence angel beta 2 of the blade is160 degrees-180 degrees. The inlet and outlet radius of the blade are 160 mm and 202 mm respectively. The connected position of the two circular arcs Rf is 180 mm-195 mm, and an incidence angel beta f of the two circular arcs is 90 degrees-120 degrees. The volute shell is formed by the connection of four smooth circular slices which center on the four angles of an equal base side. The ratio of the width of the volute shell, the width of the collector, and the axial length of the impeller is 1.31:0.26:1. The volute tongue is a bionic structure based on a leading edge profile line of a long-eared owl airfoil type. The design method of the multi-blades centrifugal fan is that the blade, the volute shell, and the volute tongue are orderly improved designed in groups. The multi-blades centrifugal fan has the advantages that the flow separation degree can be reduced, the efficiency is increased, the pneumatic property is improved obviously, the design method enable to reduce calculated amount and is higher in reliability.

Description

technical field [0001] The invention relates to the field of aerodynamics, in particular to a multi-blade centrifugal fan and a grouping design method thereof. Background technique [0002] Compared with conventional backward centrifugal fans, multi-blade centrifugal fans have the advantages of high pressure coefficient, large flow coefficient, and compact structure, but they also have disadvantages such as serious flow separation, low efficiency, and huge energy waste. Therefore, how to eliminate or alleviate The phenomenon of flow separation and the reduction of flow loss play a vital role in improving the aerodynamic performance of multi-blade centrifugal fans, expanding the application range of multi-blade centrifugal fans, and developing energy-saving and environmentally friendly products. [0003] At present, the bottleneck restricting the substantial improvement of the performance of multi-blade centrifugal fans is the optimal design method of collectors, impellers an...

AI Technical Summary

Problems solved by technology

However, most of these works focus on the improvement or optimization of a single component of the fan, without careful consideration of the matching between the dynamic and static components, especially the impeller and the volute, which limits the further improvement of the fan efficiency

In fact, limited by the size of the structure, most of the multi-blade centrifugal fans do not have diffusers, and the non-axisymmetric effect between the impeller and the volute is very obvious. The comprehensive design of the multi-blade centrifugal fan system based on the accurate simulation of real flow is still relatively limited. scarcity

Images