Engineering Thermodynamics: Pass-out Turbine Question

[PaxFinnica96]

Homework Statement

Steam at 30 bar and 500°C enters a pass-out turbine at a rate of 18000 kg h–1. The bulk of this steam is expanded isentropically to a condenser pressure of 0.03 bar, but 32% is bled from the turbine at a pressure of 3 bar for process heating. If the condensate from the process heater is directly pumped back to the boiler, find:
a) Power output from the turbine
(b) the rate of process heating
(c) the efficiency of the plant.

Relevant Equations

m=Qp1/Qp2
Q=m_p (h2-h5)
η=(Qs-Q)/q

Hello Physics Forums,
I have been struggling with this question for some time now and I'm not sure my method is correct - please see attached.
Any help you can give to check I'm on the right lines would be very much appreciated!
Cheers, C

 

[Chestermiller]

I don't understand what you're doing in the section starting with h5=hu-wp, and I don't understand what the parameters represent. Also Vu, and what it's used for.

 

[PaxFinnica96]

Hi Chestermiller, I'm not really sure where I was going with this either and as a result I'm quite confused on where to begin.
I think I should use:
p=1((h1-h4)+(1-0.32)(h4-h2))
to find the power output from the turbine but not sure if I've used the correct equations for (b) and (c).

 

[Chestermiller]

Hi Chestermiller, I'm not really sure where I was going with this either and as a result I'm quite confused on where to begin.
I think I should use:
p=1((h1-h4)+(1-0.32)(h4-h2))
to find the power output from the turbine but not sure if I've used the correct equations for (b) and (c).

If h4 is the 3 bars and h2 is the 0.03 bars, then I agree.

Please say in words your rationale for parts b and c. Also, a complete flow diagram would be helpful.