Hub casing contra-rotating type multi-stage axial flow fan

Abstract

The invention discloses a hub casing contra-rotating type multi-stage axial flow fan. The axial flow fan comprises a hub, a rotation casing arranged on the periphery of the hub coaxially, a rotation casing gear, a gear, an external motor, bearings and the like. A plurality of rows of hub movable blades are arranged on the periphery of the hub, and a plurality of casing movable blades are arranged on the inner side of the rotary casing. The casing movable blades and the hub movable blades are arranged alternatively along the axial direction of the hub, and the rotation casing gear is fixed on the periphery of the rotation casing and meshed with the gear which is connected with the external motor. The hub is connected with stators through the bearings, the rotation casing is mounted in fixed casings through the bearings, and the hub and the rotation casing rotate contrarily. According to the axial flow fan, air is fed axially and is discharged axially after being acted by alternate contra-rotation of the hub movable blades and the casing movable blades, so that flow separation of flow guide blades is prevented fundamentally, the flowing is stable and uniform, the whole fan efficiency is improved, and the whole fan pressure ratio is greatly improved.

Description

Technical field: [0001] The invention relates to the technical fields of gas transportation and ventilation, in particular to a multistage counter-rotating axial flow fan. Background technique: [0002] Due to the advantages of large flow rate and high efficiency, axial flow fans have been more and more widely used in industry, but the disadvantage of low pressure rise has become the main factor restricting its wider application. At present, in order to improve the pressure rise of axial flow fans, multiple single-stage impellers and stator blades are often connected in series in engineering to form multi-stage axial flow fans, but this type of fan requires more guide blades, which increases the The separation of the air flow on the guide vanes reduces the efficiency and workability of the whole machine. At the same time, its large axial dimension seriously restricts its industrial application range. [0003] The application of the counter-rotating fan improves the operatin...

AI Technical Summary

Problems solved by technology

However, due to the constraints of the structure and impeller stage configuration of the traditional counter-rotating fan, it is difficult to achieve multi-stage counter-rotating due to only two-stage impellers. Increasing the number of stages of the counter-cycling fan will require more motor devices and will bring shaft Due to a series of problems such as super long distance, it is difficult for the traditional counter-cyclone fan to obtain a higher pressure rise of the whole machine

Images