CLASSIFICATION OF COMPRESSORS

Compressors can be classified on the basis of range of pressures, capacity, pressure ratio and design, and principle of operations.

• On the basis of pressure range, compressors can be classified as– low pressure compressor (below 10 bar)– medium pressure compressor (10−80 bar)– high pressure compressor (80−1,000 bar)– hyper compressor (above 1,000 bar)
• On the basis of capacity, compressors can be classified as– low capacity compressor (below 0.15 m³/s)– medium capacity compressor (0.15−5 m³/s)– high capacity compressor (above 5 m³/s)
• On the basis of pressure ratio, compressors can be classified as– fan (pressure ratio below 1.1)– blower (pressure ratio between 1.1 and 2.3)– compressor (pressure ratio above 2.3)
• On the basis of design and principle of operations, compressors can be classified as shown in Figure 10.1.

Figure 10.1 Classification of Compressors

Positive Displacement Compressor: In this compressor, pressure is raised by decreasing the volume of gas, i.e., positive displacement of gas.

Dynamic Compressor: In this compressor, the kinetic energy imparted to the gas by the rotation of rotor is converted into pressure energy partly in the rotor and rest in the diffuser.