The Beijing AUX Air Conditioning Repair Center explains that a refrigeration compressor is a type of machine that increases gas pressure and plays the role of the "heart" in a refrigeration system. Based on thermodynamic principles, refrigeration compressors can be divided into two main categories: positive displacement and velocity types.
(1) Positive Displacement Refrigeration Compressors
A compressor that forcibly compresses a certain volume of gas, reducing its volume and increasing its pressure, is called a positive displacement compressor. Positive displacement compressors can further be divided into piston-type and rotary-type structures.
- Piston-type Refrigeration Compressor: This uses a crankshaft connecting rod mechanism to convert the rotational motion of the prime mover into reciprocating motion, driving the piston to move back and forth within the cylinder. This causes the volume formed by the piston and the cylinder to continuously change, thereby compressing the gas.
- Rotary-type Refrigeration Compressor: This uses the rotation of the rotor to compress gas. Depending on the form and structure of the rotor, it can be further divided into screw compressors (which can be single-screw or twin-screw), scroll compressors, rolling piston compressors, and vane compressors.
(2) Velocity-type Refrigeration Compressors
In these compressors, the increase in gas pressure is achieved through the conversion of gas velocity. Under the action of high-speed rotating impellers, the speed of the gas is significantly increased. When the gas flow stagnates, the kinetic energy is converted into pressure energy. Such a compressor is called a velocity-type compressor. Velocity-type compressors can be further divided into centrifugal compressors, axial-flow compressors, and mixed-flow compressors.
Source: Beijing AUX Air Conditioning Repair Center http://blog.tianya.cn/blogger/blog_main.asp?BlogID=3486891.
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