Gas Turbine Handbook : Principles and Practices

380 Gas Turbine Handbook: Principles and Practices
Appendix C-11
Guide for Estimating
Inlet Air Cooling Affects of
Water Fogging
Consider a gas turbine with a mass flow of 500 pounds/second (pps),
compressor efficiency of 80%, a compression ratio of 14:1, and a compressor
discharge pressure of 200 psia. Also consider ambient air at
95°F and 100% Relative Humidity (RH). Calculate the expected compressor
discharge temperature.
From the Pyschrometric Chart the Humidity Ratio is 0.0366
# moisture
#dry⋅ air
First solve for CDT in dry air at 95°F:
R o
Using η c
= c –1
..
CCT
CIT –1
Where
Rc = Compression Ratio
CIT = Compressor Inlet Temperature (°R)
CDT = Compressor Discharge Temperature (°R)
σ = K –1
K
K = C p
C v
= 1.406
C p = Ratio of Specific Heat at constant pressure
C v = Ratio of specific Heat at constant volume