Centrifugal fan and vaneless diffuser thereof

Abstract

The invention discloses a centrifugal fan and a vaneless diffuser thereof. The vaneless diffuser is an airflow channel of an impeller outlet of the centrifugal fan and a volute inlet. In the axial section of an impeller of the centrifugal fan and in the direction perpendicular to the airflow direction, the width A of the vaneless diffuser is smaller than the width B of the impeller outlet, so that airflow has the favorable pressure gradient on an inlet of the vaneless diffuser. Due to the fact that the airflow has the favorable pressure gradient partially on the inlet of the vaneless diffuser, airflow can smoothly flow into the vaneless diffuser, the risk of instable flow of vortexes and the like generated by airflow separation due to the too large adverse pressure gradient of the vaneless diffuser can be reduced as well, energy loss caused by the instable flow is reduced, the pneumatic efficiency of the centrifugal fan is improved, and caused vibration and generated noise are lowered.

Description

technical field [0001] The invention relates to the technical field of centrifugal fans, in particular to a centrifugal fan and a bladeless diffuser thereof. Background technique [0002] The centrifugal fan is a machine that relies on the input mechanical energy to increase the gas pressure and discharge the gas. It is a driven fluid machine. [0003] Such as figure 1 As shown, the centrifugal fan includes a casing, an impeller 3', a rotating shaft 4' and a bearing 5', wherein the casing is formed by connecting the volute 1' and the ring 2' through a bolt assembly, and the volute 1' is provided with a bearing Hole and vent O' out , the ring 2' has an air inlet O' in , and, the air inlet O' in Set coaxially with the bearing hole. [0004] The rotating shaft 4' is rotatable and sealed in the bearing hole of the volute 1' through the bearing 5', and the end of the rotating shaft 4' extending into the cavity is coaxially connected with the impeller 3' through an interferen...

AI Technical Summary

Problems solved by technology

[0010] This vortex flow will dissipate energy through unnecessary kinetic energy, causing a large flow loss, resulting in a decrease in the aerodynamic efficiency of the centrifugal fan and an increase in energy consumption. At the same time, the existence of this unstable flow also affects the vibration of the machine. Negative effects of noise, etc.

Images