Gas turbine is used to compress the air before entering the combustion chamber. The intercooling in gas turbine is used to cool a gas after compression.

In detail if studied about intercooler then the intercooler is known as the efficiency of compression is enhanced by compressing the gas by keeping an intercooler in between the compressor.

Hence compressing a gas increases it's internal energy which inturn increase its temperature and results in the reduction of density. Hence intercooling is used in gas turbine

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