STEAM FLOW THROUGH NOZZLES

The steam flow through the nozzle may be assumed as adiabatic flow. Since no heat is supplied or rejected by the steam during flow through a nozzle and there is no work done during the flow of steam. i.e,

Q = 0 and W = 0

Velocity Of Steam :

Steam enters the nozzle with high pressure and low velocity, and leaves with high velocity and low pressure.

The Outlet Velocity (V2) of steam can be found as follows.

Consider a unit mass flow of steam through a nozzle.

Let,

V1 = Velocity of Steam at the entrance of nozzle - m/s

V2 = Velocity of Steam at any section considered - m/s

h1 = Enthalpy of steam entering the nozzle - m/s

h2 = Enthalpy of steam at any section considered - m/s

We get from steady flow equation,

V2 = 44.72 ( h1-h2)^(1/2)

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Mechinopedia For Mechanical Engineers

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