HOW TO CALCULATE NOZZLE EFFICIENCY ?

When the steam flow through a nozzle ,some loss in its total heat takes place due to friction between the nozzle surface and the flowing steam . The effect of friction is increase the dryness fraction of steam .

This is due to the fact that the energy lost in friction is transferred in to heat , which tends to dry or super heat the steam,The nozzle efficiency or the coefficient of nozzle is defined as the ratio of useful heat drop to the isentropic heat drop . Mathematically nozzle efficiency.

The following are the three types of nozzles :

Convergent nozzle
Divergent nozzle
Convergent - Divergent nozzle


Convergent nozzle

Divergent nozzle

Convergent - Divergent nozzle