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**1. The problem statement, all variables and given/known data**

A steam turbine in a small electric power plant is designed to accept 4500 kg of steam at 60 bar and 500oC and exhaust the stem at 10 bar.

Part C.

In off-peak hours, the power output of the turbine in part a) (100% efficient) is decreased by adjusting a throttling valve that reduces the turbine inlet steam pressure to 30 bar while keeping the flow rate constant. Compute T1, the steam temperature to the turbine, Tr, the steam temperature at the turbine exit, and the power output of the turbine.

**2. Relevant equations**

Sautrated steam table, superheated water table, linear interpolation

P=m (H2-H1)

Entropy balance

**3. The attempt at a solution**

I know a valve is isenthalpic so I worked out for the new tempature of the steam and got 484C . I know turbines are isentropic so the entropy will remain the same from inlet to outlet. My only question is will my outlet pressure change from changing my inlet pressure from 60to 30 bar? or do I keep it the same as the problem statement in the first part which is 10 bar? Or is the pressure changing at the outlet as well? If it is how is it changing?

Any and all help is appreciated

Best regards,

D