In fact, air compressor and compressor are two completely different mechanical products with certain commonness and connection. Their use scenarios and working principles are different, not as we usually think that air compressor is compressor.
The concept and difference between the two
An air compressor is an air compressor. Mainly used for compressed air mechanical products, in many places will be used. For example, one of the most commonly used functions of air compressor is to compress air for power, which is widely used in the power industry. In addition, it can also be used to cool and separate gas, transport gas and so on. It plays a very important role in life and work.
The compressor is a general term, is a kind of low-pressure gas to high-pressure gas driven fluid machinery. And there are many kinds of compressors, such as refrigerant compressor, hydrogen compressor and air compressor and so on. The air compressor is just one of the compressors.
Many people think that air pump is air compressor. Air pump is a long time ago said that the piston type air compressor, now air compressor types are more, screw machine, oil-free machine, energy-saving frequency conversion air compressor and so on. The principle of air pump and air compressor is different.
The two principles
Working principle of air compressor:
Taking screw air compressor as an example, the working cycle of screw compressor can be divided into three processes: intake, compression and exhaust. As the rotor rotates, each pair of meshing teeth successively complete the same working cycle.
1. Air intake process: when the rotor rotates, the space of the tooth groove of the male and female rotors is the largest when it turns to the opening of the air intake end wall. At this time, the space of the tooth groove of the rotor is connected with the air inlet. Because the gas in the tooth groove is completely discharged when the exhaust is completed, the tooth groove is in a vacuum state. When it turns to the air inlet, the external gas is sucked in and enters the tooth groove of the male and female rotors along the axial direction 。 When the gas is full of the entire groove, the end face of the rotor inlet side turns away from the air inlet of the casing, and the gas in the groove is closed.
2. Compression process: when the suction of the male and female rotors is finished, the tooth tips of the male and female rotors will be closed with the casing, at this time, the gas will not flow out in the groove. The meshing surface gradually moves to the exhaust end. The groove space between the meshing surface and the exhaust port becomes smaller and smaller, and the gas in the groove is compressed to increase the pressure.
3. Exhaust process: when the meshing end face of the rotor turns to be connected with the exhaust port of the casing, the compressed gas starts to exhaust until the meshing surface of the tooth tip and the tooth groove moves to the exhaust end face. At this time, the space between the meshing surface of the male and female rotors and the tooth groove of the exhaust port of the casing is 0, that is to say, the exhaust process is completed. At the same time, the length of the tooth groove between the meshing surface of the rotor and the air inlet of the casing reaches the maximum, The intake process is repeated.
Working principle of process compressor:
Taking the common centrifugal compressor as an example, the turbine (or motor) drives the main shaft impeller of the compressor to rotate. Under the centrifugal force, the gas is thrown into the diffuser behind the working wheel. A thin zone is formed in the middle of the working wheel, and the gas in front enters the impeller from the steam inlet part in the middle of the working wheel. As the working wheel rotates continuously, the gas can be continuously thrown out, thus maintaining the continuous flow of gas in the air compressor. The pressure of gas is increased by centrifugal action, and the gas can leave the working wheel at a great speed. The speed of gas is gradually reduced by the diffuser, and the kinetic energy is converted into static pressure energy, which further increases the pressure. If the pressure of a working impeller is not enough, the outlet pressure can be achieved by connecting the multi-stage impellers in series. The series connection between stages is realized by bending and reflux. This is the working principle of centrifugal compressor.