Compressors Interstage Cooling
Where more than one stage of compression is involved, it is desirable from the point of view of maximum efficiency that each stage does an equal amount of work. This can only be realized if the temperature of the air into the second stage is similar to that of the air inducted into the first stage. Cooling by means of a water jacket or finned cylinders will only remove a proportion of the heat generated by compression, because not all the air passing through the compressor will come into contact with the cooled surfaces of the cylinder walls. With an efficient water cooling system applied to a reciprocating compressor cylinder, only about 10 to 15% of the heat generated will be removed. Extra cooling between stages will be needed to bring the temperature down to an acceptable value. This will involve a separate heat exchanger.