It is not preferable to use superheated steam in evaporators, because of its very_________________?
Correct answer: D. Low film co-efficient
- A. High temperature
- B. High pressure
- C. None of these
- D. Low film co-efficient
Explanation
Superheated steam must first be desuperheated before condensation begins, and heat transfer from superheated steam has a much lower film coefficient than from condensing saturated steam. This makes it less effective as an evaporator heating medium.
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