There are significant differences between rotary fans and Roots blowers in multiple aspects. The following is a detailed comparison between the two:
1、 Working principle
1. Rotary fan:
Rotary fan belongs to a type of centrifugal fan, which works by using centrifugal force to suck in air or gas, and then generating a high-pressure force difference through the high-speed rotation of the internal rotor to provide flow power.
Another explanation is that rotary fans rely on the movable blades on the rotor to compress air.
2. Roots blower:
The Roots blower squeezes air through the meshing of two impellers (also known as the engagement between a double rotating gear and a sleeve).
As the rotor rotates, the space between them gradually decreases, allowing gas to be drawn in and compressed through the intake port, and finally discharged through the exhaust port.
2、 Structural characteristics
1. Rotary fan:
Having impellers and rotating components, the structure is relatively complex.
The flow rate can be adjusted by adjusting the speed.
2. Roots blower:
Composed of two concentric rotors rotating and meshing together, the structure is relatively simple.
Usually designed as a constant flow pattern, direct flow regulation is not possible (but can be indirectly adjusted by adjusting the speed or bypassing the air).
3、 Scope of application and performance
1. Rotary fan:
The pressure is relatively high, but the flow rate is relatively small.
Suitable for occasions with low air volume requirements but high pressure requirements.
The noise is relatively low (but still produces noise during high-speed operation), and the energy consumption may be high.
3. Roots blower:
Capable of delivering larger air volume and lower pressure.
Suitable for conveying dry, clean, and non corrosive gases.
The operation is relatively stable and efficient, with a long service life.
The noise is relatively high (but can be improved through noise reduction measures).
4、 Output air quality
1. Rotary fan:
Due to its structural characteristics and working principle, the output air may contain a certain amount of oil.
2. Roots blower:
The gaps between rotors and between rotors and cylinders are tightly controlled, and the discharged gas is not contaminated by lubricating oil, so the output air does not contain oil.
5、 Other precautions
1. Rotary fan:
Small size and easy installation.
Strong resistance to load changes and stable air flow.
Equipped with an air chamber for smooth air dispersion.
Excellent material, clever structure, and performance.
Easy maintenance and minimal malfunctions, with a long service life (but regular maintenance and upkeep are important).
2. Roots blower:
The displacement is 1-150 cubic meters per minute, and the speed is 800-1700 revolutions per minute (specific parameters depend on the model and specifications).
Attention should be paid to temperature limitations when using (usually not exceeding 40 ℃).
Due to its oil-free output air and wide applicability (including sewage treatment aeration, pneumatic conveying, and other fields), it is more suitable for places with higher air quality requirements.
In summary, there are significant differences between rotary fans and Roots blowers in terms of working principles, structural characteristics, applicability and performance, as well as output air quality. When choosing, comprehensive consideration should be given to specific needs and application scenarios.
