Question:-
The effect of friction in a steam nozzle is to
Option (A)
Increases velocity and increases dryness fraction
Option (B)
Increases velocity and decreases dryness fraction
Option(C)
Decreases velocity and increases dryness fraction
Option(D)
Decreases velocity and decreases dryness fraction
Correct Option:
(C)
Question Solution:
Due to fluid friction the expansion process is no longer isentropic, but is irreversible and still adiabatic (Q=0). Friction reduces the enthalpy drop by 10 to 15% and thus reducing the exist velocity. Being adiabatic condition, the heat generated due to friction goes back to steam and improves the dryness friction at exist due to heating effect
question-answer-faq-2827