Difference between three blade roots blower and two blade roots blower:

Many people think that the three blade roots blower has one more leaf than the two blade roots blower, but they simply think that under the condition of the same radius of the center to the outer circle, the two blade roots blower has a larger exhaust volume than the three blade roots blower, which is a wrong view.

For the involute impeller, since the area utilization coefficient has nothing to do with the number of impeller heads, that is, when the involute impeller is selected, the two blade and three blade fans have the same displacement when their main parameters are the same. When the blade profile is selected properly, the theoretical gas transmission capacity of three blades is greater than that of two blades.

1. When the center distance and the radius of the outer circle are the same, the displacement of the three blade Roots fan with circular blade is larger than that of the two blade Roots fan. The displacement of the fan with involute blades has nothing to do with the number of rotor heads.

2. The mechanical performance of three blade roots is better, which can better ensure the clearance between impellers and between impellers and casing than that of two blade roots.

3. The vibration and noise of the three blade roots blower is smaller than that of the two blade roots blower, and the life of the bearing used on the three blade roots blower is about 15% longer than that used on the two blade roots blower. Moreover, the three blade rotor can use twisted blade rotor to reduce its noise and vibration, while the two blade rotor cannot use twisted blade structure due to structural limitations.

4. Three blade Roots fans, especially twisted blade fans, are more and more used in automotive supercharging due to their good noise and dynamic balance performance. With the development of machining technology, mass production of three blade straight blade rotors is no longer a problem. The efficiency of machining twisted blade rotors on CNC machine tools is also increasing. As the three blade rotor blower has obvious advantages over the two blade rotor blower, its application will be more extensive.