Thermodynamics: Pass-out Turbine Question

Click For Summary
SUMMARY

The discussion focuses on calculating the power output of a pass-out turbine using the equation p=1((h1-h4)+(1-0.32)(h4-h2)). Participants express confusion regarding the parameters involved, particularly h5, Vu, and the rationale behind the equations for parts (b) and (c). The need for a complete flow diagram is emphasized to clarify the process. The conversation highlights the importance of understanding thermodynamic principles in turbine performance analysis.

PREREQUISITES
  • Understanding of thermodynamic cycles and processes
  • Familiarity with turbine operation and performance metrics
  • Knowledge of enthalpy and pressure relationships in fluid dynamics
  • Ability to interpret and create flow diagrams for engineering systems
NEXT STEPS
  • Study the principles of thermodynamic cycles, focusing on Rankine and Brayton cycles
  • Learn about the specific enthalpy calculations in steam turbines
  • Research flow diagram creation techniques for thermodynamic systems
  • Explore advanced turbine performance analysis methods, including efficiency calculations
USEFUL FOR

Engineering students, mechanical engineers, and professionals involved in turbine design and analysis will benefit from this discussion, particularly those focusing on thermodynamics and fluid mechanics.

PaxFinnica96
Messages
14
Reaction score
0
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
 

Attachments

Physics news on Phys.org
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.
 
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).
 
PaxFinnica96 said:
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.
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 9 ·
Replies
9
Views
2K
Replies
21
Views
9K
Replies
1
Views
2K
Replies
2
Views
1K
  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 33 ·
2
Replies
33
Views
8K
  • · Replies 7 ·
Replies
7
Views
3K