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Which of the following statements are correct with respect to regenerative feed heating in a steam cycle? 1. It increases cycle efficiency 2. It increases specific output 3. It reduces the condenser load 4. It improves the steam quality at the end of expansion

Which of the following statements are correct with respect to regenerative feed heating in a steam cycle? 1. It increases cycle efficiency 2. It increases specific output 3. It reduces the condenser load 4. It improves the steam quality at the end of expansion Correct Answer 1 and 3 only 

Concept:

The regeneration in the Rankine cycle is done by the bleeding the steam from the high pressure turbine after the partial expansion of the steam in the turbine, and it preheats the condensed liquid before it returns back to the boiler.

In this way, the amount of heat rejected at the low temperatures is reduced (less mass flow rate) and the mean effective temperature of heat addition is increased, thus cycle efficiency is increased.

The amount of steam that does not get fully expanded in the turbine leads to some reduction in the work output.

The capacity of the condenser is reduced because a small fraction of the steam is not reaching the condenser now.

There won't be any change in steam quality as there is no change in the pressure limits of the regenerative Rankine cycle.

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