Finding Turbine Inlet State - Thermodynamics

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Magnawolf
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Homework Statement


max. Turbine work output rate: 6.0MW
Turbine isentropic efficiency: 90%
Turbine exit state (isentropic): 40KPa, x=92%
Turbine and pump actual process are assumed adiabatic

Find turbine inlet state: Pinlet, Tinlet, Sinlet

Homework Equations


W = ΔH
h = hf + xhfg

The Attempt at a Solution


I find hexit = hf + 0.92hfg

where hf = hf @ 40KPa = 317.62 on sat. liquid table and hfg=2318.4. So then I find hexit = 2450.18 kj/kg.

Then I do Wturbine = h1 - h2' to find h1 = hinlet = 8636.1 kj/kg. I then tried to look up that h on the superheated table to find the pressure and temperature and stuff but that's way too high of a number. I need help!
 
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Magnawolf said:
Then I do Wturbine = h1 - h2' to find h1 = hinlet = 8636.1 kj/kg. I then tried to look up that h on the superheated table to find the pressure and temperature and stuff but that's way too high of a number. I need help!

How? Where did you get Wturbine ? (units of kW/kg/s) You don't have a a mass flow rate to find Wturbine.
Have you included the entire problem statement?