Stainless Steel Centrifugal Blower Fan Backward Curved For Industrial Boiler

Backward curved centrifugal blower mass flow rate brushless dc electric motor high efficiency fan vibration four points

Centrifugal fan vibration is very big, what is the reason?

1. The vibration caused by the pulsation of the bellows vortex. The structure design of the inlet bellow is not reasonable, which causes the air flow in the inlet bellow to produce a violent vortex, and it is accelerated and expanded in the inlet collector of the centrifugal fan, thus stimulating a large pulsating pressure wave. The vibration characteristics are as follows: the pressure wave is often irregular, and the amplitude increases with the increase of flow rate.

2. Vibration caused by local eddy current in air duct. The design of some components of the air duct (elbow, diffusion pipe section) is not reasonable, resulting in poor airflow flow. Local eddy current or airflow interference and collision in the air duct cause pressure pulsation of the air flow, thereby exciting noise and vibration of the air duct. Its vibration characteristics: the vibration is irregular, and the amplitude increases with the increase of load.

3, centrifugal fan shell and duct wall stiffness is not enough to cause vibration. Where the stiffness is weaker, the amplitude is larger.

4. Rotation stall. When the airflow Angle of attack reaches the critical value, the airflow will leave the convex surface of the blade, and the boundary layer separation will occur, resulting in a large number of areas of eddy current, resulting in the wind pressure drop of the fan. Rotational stall mainly occurs in axial flow fans, and in the impeller and blade diffuser of centrifugal fans, due to the reduction of flow, rotational stall will also occur.

Characteristics of vibration caused by rotational stall:

(1) The vibration part is often in the inlet box and outlet air duct of the fan.

(2) Vibration mostly occurs on the fan of imported louver type regulating baffle and backbending blade.

(3) Strong vibration occurs when the baffle opening is 0-30%, and it drops to the normal value when the baffle opening is more than 30%.

(4) When the rotation stall occurs, the flow and pressure of the centrifugal fan produce strong pulsation.

 
Key Features 

• Impeller diameter: 90~3500 mm 
• Speed of mainshaft: 560~2900 rpm
• Pressure range: 3000~25425 Pa
• Flow range: 1297~83305 m3/h
• Air Temperature: 20~1000 Celsius degree

• Material: Cast Iron, Carbon Steel, Stainless Steel.

• Efficiency: 80%-90%

Please advise us the USAGE and following Parameter.Our engineering Dept will recommend the most suitable product for you.