Understanding Brayton Cycle Temperatures: Finding Outlet Flow Rate"

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SUMMARY

The discussion focuses on calculating outlet flow rates in the Brayton Cycle, specifically identifying the necessary temperature values for the Second Law of Thermodynamics (SFEE) application. The user is attempting to determine temperatures T3 and T4, given known parameters such as shaft power, inlet velocity, mass flow rate, and specific heat capacities (cp). The key equation referenced is cp(deltaT) = deltaH, with the user suggesting that T4 - T1 is critical for their calculations. The challenge lies in obtaining T3 on the constant pressure line without provided volumes or heat input data.

PREREQUISITES
  • Understanding of the Brayton Cycle and its thermodynamic processes
  • Familiarity with the application of the Second Law of Thermodynamics (SFEE)
  • Knowledge of specific heat capacities (cp) and their role in energy calculations
  • Basic principles of thermodynamic cycles, including turbine and compressor operations
NEXT STEPS
  • Research methods for calculating temperature at constant pressure in the Brayton Cycle
  • Study the relationship between shaft power and thermal efficiency in gas turbines
  • Explore the impact of mass flow rate on temperature and pressure in thermodynamic cycles
  • Learn about the role of heat input in determining cycle performance and efficiency
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Students preparing for exams in thermodynamics, engineers working with gas turbine systems, and professionals involved in energy cycle analysis.

grolschey
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This is a general concern with finding temperature values at different processes in the cycle, however i do have an example i am stuck on, and can post that if needs be. anyway, if i was required to find the flow rate at outlet, which temperatures would i need to put in the SFEE as i know cp(deltaT) = deltaH, my guess is T4 - T1. how would i go about getting temperature 3 and 4, I can get temperature 2 no problem, my main problem lies with calculating T3 on the constant pressure line, there is no volumes given and neither is the heat input at constant pressure. I basically have the shaft power, the inlet velocity, the mass flow rate, the pressures, cp and gamma, and temperature at inlet, which i assume is T1...?

any help would be great, as i have an exam tomorrow and this seems to be the only sticking point for me.

Thanks in advance

Edit: It has come to my attention that this may well come under the subject of homework-type questions. however as i am not sure, and it seems pretty general to me, i will leave it here which i hope is not to much of a problem, and if required i or a moderator can move the post. :)
 
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nevermind the temperature it has given me is T3 in the cycle, i believe its the turbine inlet conditions given, rather than the compressor, as if it was i would need a max cycle temp to work out the other unkowns.
 

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