Gas Turbine Compressor Efficiency
Gas Turbine Compressor Efficiency
(OP)
I know that this subject has been covered before on this site. However, I was interested in learning more about tracking compressor efficiency using enthalpy. I have access to an excel add-in that will calculate enthalpies and entropies based on pressure, temperature, and humidity. This excel add-in is based on ASHRAE tables and it's accuracy has been documented.
The basic formula that I am using is eff = (H2s-H1)/(H2-H1).
Where:
H1 = Actual Enthalpy In
H2s = Isentropic Enthalpy Out
H2= Actual Enthalpy Out
I was wondering if this is an accurate way of performing a compressor efficiency calculation, and any other advice would be appreciated as well.
Thank You
The basic formula that I am using is eff = (H2s-H1)/(H2-H1).
Where:
H1 = Actual Enthalpy In
H2s = Isentropic Enthalpy Out
H2= Actual Enthalpy Out
I was wondering if this is an accurate way of performing a compressor efficiency calculation, and any other advice would be appreciated as well.
Thank You





RE: Gas Turbine Compressor Efficiency
"We don't believe things because they are true, things are true because we believe them."
RE: Gas Turbine Compressor Efficiency
RE: Gas Turbine Compressor Efficiency
"We don't believe things because they are true, things are true because we believe them."
RE: Gas Turbine Compressor Efficiency
if it's a polytropic process you need to follow a polytropic path with specified efficiency,
this is usually a iterative procedure unless you are able to integrate a simplified model,
you may find some numerical examples in http://www.prode.com/docs/pppman.pdf
RE: Gas Turbine Compressor Efficiency
I thought that comparing real enthalpy and isentropic enthalpy was like comparing the reversible aspect of the process to the non-reversible aspect. Is this correct?
RE: Gas Turbine Compressor Efficiency
still we can create models and simulate processes,
for a compression cycle a polytropic path can be defined as t*dS/dt = C
and since for real fluids properties are not constant you need to integrate pin=>pout to calculate tout and work.