In the process of use, the impeller is the heart of the fan. The backward curved impeller fan is to some extent different from the type of impeller used by the different fans. During the manufacturing process, the impeller of the equipment is compared with the axial flow. The impeller of the fan is more complex, and its process requirements will be higher when it is operated. According to the blade angle of the impeller outlet, three kinds of impeller flavor can be used: forward, radial and backward.
The angle of the outlet blade of the backward curved impeller fan is β2>90°. When used, the outlet wind pressure is high, but the efficiency is low. The forward-type blades easily accumulate impurities between the impellers and are easily fouled. During the operation, it is mainly used for the general air volume, but the relatively high area is required, and the widely used blades are generally narrow and have a large quantity.
The radial vane of the backward curved impeller fan has a blade outlet angle β2=90°. The structure of the entire device is simple and the production cost is low. The parameters of the device will be between the forward and backward types to some extent. , but the efficiency is low, so the application is not very extensive, but due to its non-fouling characteristics, it is only used in a few occasions such as mines.
The backward-bending impeller blower will have excellent aerodynamic performance during the operation. When it is used, the air blower has large air volume and low pressure, but the efficiency is very high. The domestic general backward-type impeller centrifugal fan, The efficiency can reach 80%-90%, so it is widely used, and because it is not easy to scale, it is widely used in industries, chemical industries, power plants and other fields.
The backward curved impeller fan will be partly the same as the wing due to its blade section, so it is called the backward wing-type blade. During the production process, due to its unique structural characteristics, the impeller is undergoing the production process. The required process is also very strict, and the unique blade form can make it maintain a certain degree of power change under large flow conditions, and has a certain protection effect on the equipment safety of the fan.