Psychrometrics of Cooling
Turbine Inlet Cooling:ASME Turbo Expo 2011
Presented by: Annette Dwyer
Munters Corporation
Psychrometrics
10 20 30 40 50 60 70 80 90 100 110 120
Dry Bulb Temperature, Deg. F
0.000
0.005
0.010
0.015
0.020
0.025
0.030H
umidity
Ratio, lb M
oisture/lb Dry A
ir
10 20 30 40 50 60 70 80 90 100 110 120
Dry Bulb Temperature, Deg. F
0.000
0.005
0.010
0.015
0.020
0.025
0.030H
umidity
Ratio, lb M
oisture/lb Dry A
ir
Rain or Fog
Saturation Line or
100% Relative Humidity
10 20 30 40 50 60 70 80 90 100 110 120
Dry Bulb Temperature, Deg. F
0.000
0.005
0.010
0.015
0.020
0.025
0.030H
umidity
Ratio, lb M
oisture/lb Dry A
ir
100%
50%
20%
10%
10 20 30 40 50 60 70 80 90 100 110 120
Dry Bulb Temperature, Deg. F
0.000
0.005
0.010
0.015
0.020
0.025
0.030
Hum
idityR
atio, lb Moisture/lb D
ry Air
100%
50%
10%
20%
10 20 30 40 50 60 70 80 90 100 110 1200.000
0.005
0.010
0.015
0.020
0.025
0.030
Cool Heat
Dew Point Temperature (DP, ºF)The temperature at which existing moisture will condense from the air(forming dew)
Wet Bulb Temperature
Dry
Bul
b Te
mpe
ratu
re
Dew Point Temperature
100%
RH
10%
2030
40
50
60
80
70
10 20 30 40 50 60 70 80 90 100 110 120
Dry Bulb Temperature, Deg. F
0.000
0.005
0.010
0.015
0.020
0.025
0.030H
umidity
Ratio, lb M
oisture/lb Dry A
ir
20%
30%
RH
40%
RH
50%
RH
60%
RH
80%
RH
Measuring the Wet Bulb Temperature
10 20 30 40 50 60 70 80 90 100 110 120
Dry Bulb Temperature, Deg. F
0.000
0.005
0.010
0.015
0.020
0.025
0.030H
umidity
Ratio, lb M
oisture/lb Dry A
ir
100%
50%
20%
10%
2030
40
50
60
80
70
Wet Bulb Depression = 108 - 66
660
1080
10 20 30 40 50 60 70 80 90 100 110 120
Dry Bulb Temperature, Deg. F
0.000
0.005
0.010
0.015
0.020
0.025
0.030H
umidity R
atio, lb Moisture/lb D
ry Air
100%
50%
20%
10%
2030
40
50
60
80
70
Cooling = .90 X (108-66)
DIRECT EVAPORATIVE COOLING
70.2108
10 20 30 40 50 60 70 80 90 100 110 120
Dry Bulb Temperature, Deg. F
0.000
0.005
0.010
0.015
0.020
0.025
0.030H
umidity R
atio, lb Moisture/lb D
ry Air
100%
50%
20%
10%
2030
40
50
60
80
70
780/91.6%
950/45%
1080/9%
70.20/81.2%
390/90%
680/20%
500 /87%
500/30%
A 90% Effective Evaporative Cooler Will Cool 90% of the Wet Bulb Depression
Regardless of the Starting Point
Hum
idity Ratio, lb M
oisture/lb Dry A
ir
Mechanical Cooling
10 20 30 40 50 60 70 80 90 100 110 120
Dry Bulb Temperature, Deg. F
0.000
0.005
0.010
0.015
0.020
0.025
0.030
100%
50%
20%
10%
Warm Air Cool Air
2030
40
50
60
80
70
Chiller Coil
Las Vegas
Fort Myers
Chilled Coils
1000/700
Indirect Evaporative Cooling
2030
40
50
60
80
70
10 20 30 40 50 60 70 80 90 100 110 120
Dry Bulb Temperature, Deg. F
0.000
0.005
0.010
0.015
0.020
0.025
0.030H
umidiity
Ratio, lb M
oisture/lb Dry A
ir
790 0
790/620
PrimaryAir Stream
10 20 30 40 50 60 70 80 90 100 110 1200.000
0.005
0.010
0.015
0.020
0.025
0.030
100%
50%
20%
10%
Secondary Air Stream Exhaust
Cold water
Warm water0 0Indirect /70100
/62
INDIRECT - DIRECT EVAPORATIVE COOLING
1000/700
63.7/0/62 0790/6201000/700
2030
40
50
60
80
70
75.2060.50
63.7/0/62.00
10 20 30 40 50 60 70 80 90 100 110 120
Dry Bulb Temperature, Deg. F
0.000
0.005
0.010
0.015
0.020
0.025
0.030H
umidiity
Ratio, lb M
oisture/lb Dry A
ir
100%
50%
20%
10%Indirect
INDIRECTEVAPORATIVECOOLER
DIRECT EVAPORATIVECOOLER
Direct790/620
Direct Only
73º
INDIRECT - DIRECT EVAPORATIVE COOLING WITH CHILLED WATER ASSIST
1000/700
64.4/0/60.50790/630 75.2060.501000/700
2030
40
50
60
80
70
75.2060.50
64.4/0/61.50
10 20 30 40 50 60 70 80 90 100 110 120
Dry Bulb Temperature, Deg. F
0.000
0.005
0.010
0.015
0.020
0.025
0.030H
umidiity
Ratio, lb M
oisture/lb Dry A
ir
100%
50%
20%
10%IndirectCoil
INDIRECTEVAPORATIVECOOLER
IDXOR CWICOIL
DIRECT EVAPORATIVECOOLER
Direct
790/630
Psychrometrics of Cooling
Turbine Inlet Cooling:ASME Turbo Expo 2011
Presented by: Annette Dwyer
Munters Corporation