Describe any two sources of air leak in surface condenser. Also describe effect of air leak on latent heat of steam and cooling water requirements.

1 Answer

Answer :

✓ The main sources of air leakage found in condenser are given below: 1) There is leakage of air from atmosphere at the joint of the parts which are internally under a pressure less than atmospheric pressure. 2) Air is also accompanied with steam from the boiler into which it enters dissolved in feed water. 3) In jet condensers, a little quantity of air accompanies the injection water. 

✓ Effects of Air Leakage in Condenser 1) The performance of condenser is affected by air leakage: 2) The increased amount of air in the condenser, the condenser pressure or back pressure is increased; this reduces the useful work done in the prime mover. 3) Presence of air also lowers the partial pressure of steam which decreases the saturation temperature of steam and hence evaporation enthalpy of steam increases therefore more amount of cooling water required in the condenser. 

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