Heat rejection accounting in a multi-stage reciprocating air compressor with intercooling. Validate the energy balance statement: The total heat rejected equals (heat rejected during polytropic compression per kg of air) + (heat rejected in the intercooler per kg of air). Choose whether the statement is correct.

Concept/ApproachApply the first law to each stage and the intercooler. Heat removed from the gas occurs during the compression process (if cooled) and additionally in the intercooler between stages.

Energy balanceQ_{total out} = Σ Q_{polytropic (per kg)} + Σ Q_{intercooler (per kg)}Work input is reduced by intercooling since the specific volume at the start of the next stage is lower.

Final AnswerAgree.