Centrifugal fans, axial fans andRoots FansAs fans commonly used in industry, what is their function? Already what is the difference between them? I will take you to understand.
1. Centrifugal fan
Centrifugal fan is a machine that relies on the input of mechanical energy to increase the gas pressure and discharge the gas, it is a kind of slave fluid machinery.
2、Axial flow fan
Axial fan, that is, the airflow in the same direction as the axis of the fan blade (i.e., the flow of wind and the axis parallel), such as electric fans, air conditioning external fan is the axial flow way to run the fan.
3.Roots fan
Roots fan is a volumetric fan, conveying the air volume is proportional to the number of revolutions, the three-lobe impeller each rotation by the two impellers for three suction and exhaust, compared with the two-lobe type, the gas pulsation becomes less, the load change is small, the mechanical strength is high, the noise is low, and the vibration is also small. There are 2 three-lobe type impellers on the shaft of 2 flat phase rows, the wheel and oval chassis bore surface and the impeller always keep a small gap between the three, because the impeller is the opposite direction of each other and rotate at a constant speed, so that the box and the impeller surrounded by a certain amount of gas by the inhalation of one side of the conveyor to the side of the discharge. The impellers are always kept in the correct phase by the synchronous gears and do not touch each other, thus they can be high-speed and do not need internal lubrication, and they have a simple structure, smooth operation, stable performance, adapt to a variety of uses, and have been used in a wide range of fields.
4. Difference between Roots fan and centrifugal fan:
① The working principle is different, centrifugal fan uses curved airfoils, relying on centrifugal force to fling the gas to the casing, while Roots fan uses two figure-of-eight airfoils, the gap between them is very small, relying on the extrusion of the two blades, the gas will be squeezed to the air outlet;
② Due to the different working principles, generally they work at different pressures, Roots fan outlet pressure is higher, while the centrifugal fan is smaller;
③ The air volume is different, generally the Roots fan is used in the place where the air volume requirement is not big but the pressure requirement is high, while the centrifugal fan is used in the place where the pressure requirement is low and the air volume requirement is big;
④ Manufacturing precision is not the same, Roots fan requires high precision and strict assembly requirements, while the centrifugal fan is more loose.