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Ambient Conditions Dry (F) Wet (F) %RH

Average 47 42 67

45.5 43 78

47 46.5 43.5 42.83333333 76 73.66666667

Air from Cooling Tower Dry (F) 58 Wet (F) 54 %RH 73

56 53 81

53 55.66666667 51 52.66666667 87 80.33333333

Air Velocity (m/s) Position Meter 1 Meter 2 Average A 3.8 4 3.9 B 3.3 3.4 3.35 C 4.2 4.5 4.35 D 4.6 4.7 4.65 E 3.8 4 3.9 F 4.5 4.6 4.55 G 3.7 3.8 3.75 H 4.1 4.2 4.15 I 3.6 3.2 3.4 3.955555556 4.044444444 4 Cold Water Return (gal/sec) Vol (gal) Time (sec) Rate (gal/sec) 5 51.8 0.096525097 5 49.82 0.100361301 5 49.83 0.10034116 0.099075852

Temperatures CWS (C) CWR (C) 10.7 13.9 CWS (F) CWR (F) 51.26 57.02

Mass Flow Rate of Air (lbs/hr) On Ambient 14011.94329

Heat Rate based on Air Flow (Btu/h On Ambient 155168.7225

Mass Flow Rate of Water (lbs/hr) 5408.146978

ass Flow Rate of Air (lbs/hr) On CT Flow Average 13745.59025 13878.77

eat Rate based on Air Flow (Btu/hr) On CT Flow Dheat 186042.9599 30874.24

ass Flow Rate of Water (lbs/hr)

Second attempt at calculating the change in enthalpy of the cooling tower. Velocity flow rate of air out of the cooling tower 3" rad dis 6" rad dis 9" rad dis Section A 4.8 5 5.6 Section A 4.2 5.1 4.9 Section A 4.5 4.8 5 Section B 4.3 6 4.6 Section B 4.8 5.7 5.3 Section B 5.1 5.7 3.9 Section C 3.3 4.9 4.9 Section C 4 4.8 4.8 Section C 3.5 3.7 4.2 Average 4.2777777778 5.0777777778 4.8 50524.833333333 59973.633333333 56692.8 0 3 6 9 0 151574.5 359841.8 510235.2 3 3 3 75787.25 255708.15 435038.5 227361.75 767124.45 1305115.5

Change in enthalpy on the air side Ambient air conditions Dry Bulb (F) Wet Bulb (F) Rel Hum %

1 54 48

Air from Cooling Tower Dry Bulb (F) Wet Bulb (F) Rel Hum %

1 58 55

12 0 3 255117.6 vol flow rate (ft^3/hr) 765352.8 133733.86862204

Ave Vel 4.5" Ave Vel 7.5" Ave Vel 12" Vol (ft^3/hr) 22321.187608966 11775.795367732 25046.11181058 59143.094787277 Densities of H2O and air (kg/m^3) H2O vap Dry air 10.85305 1.23139 Vap (lb/ft^3) Air (lb/ft^3) 0.6775342054 0.0768732149

Cpair,in (J/kgK) Cpvap,in (J/kgK) 1006.7022222222 4194.2 Cpair,in (Btu/lbF) Cpvap,in (Btu/lbF) 0.2404608928 1.001826612 0.575421837 AveCpin(Btu/lbF) AveCpout(Btu/lbF) 0.4155750082 0.3696437377

Mass 4.5" Mass 7.5" Mass 12" Mass (lbs/hr) 12844.098778384 6776.0498028528 14412.079668212 34032.228249448

Calculation of change in enthalpy

22.357935442 cu ft/lb dry air mass flow of air h in h out lb H2O/lb air in lb H2O/lb air out lb H2O lost delta h

13.25 10093.122160154 19.4 23.7 0.006 0.009 30.2793664805 43400.425288663

21.8089805236

2 54 47

3 59 56

4 55 50

4 61 57

5 Averages 52 49

5 Averages 59 55

53.8 48.4 77

600000 500000

59 55.8 83

400000 Ave Vel

2 58 56

3 54 48

300000 200000 100000 0

Cpair,out (J/kgK) Cpvap,out (J/kgK) 1006.76 4,188 Cpair,out (Btu/lbF)Cpvap,out (Btu/lbF) 0.2404746936 1.0002926

out(Btu/lbF)

0

2

4

6

Radial Distance (i

0.5489549184 18682.159082626

600000 500000 400000 300000 Row 17

200000 100000 0 0

2

4

6

8

10

Radial Distance (inches)

12

14

Position

0" Rad Dis 1 2 3 4 5 6 7 8 9

Average (m/s) Standard Dev

3" Rad Dis 0 0 0 0 0 0 0 0 0 0 0 0 0

Base Height

4.6 4.2 4.4 4.4 4.5 4.7 3.9 4.3 3.7 4.3 0.32 50787.3 3 152361.9 3 76181.0 228542.9

6" Rad Dis 5 5.1 4.9 5.7 5.5 5.4 4.5 4.7 4 4.98 0.53 58792.5 6 352755.2 3 252558.6 757675.7

9" Rad Dis 5.4 4.4 4.6 4.1 4.7 4.3 4.2 4.7 3.9 4.48 0.44 52887.0 9 475983.3 3 414369.3 1243107.8

Unsteady state temperature changes for cold water supply and return (F) Time (sec) Time (min) CWReturn CWSupply Dh(Btu/hr) 0 0 72 107.5 -109908 30 0.5 71.5 98.8 -84520.8 60 1 67.2 93.8 -82353.6 90 1.5 69.1 89.9 -64396.8 120 2 70.2 85.5 -47368.8 150 2.5 71.8 82 -31579.2 180 3 73.4 79.5 -18885.6 210 3.5 74.3 76.4 -6501.6 240 4 75.3 73.2 6501.6 270 4.5 76.4 71.8 14241.6 300 5 76.6 69.8 21052.8 330 5.5 77.6 68 29721.6 360 6 77.7 66.7 34056 390 6.5 78.1 65.6 38700 420 7 77.9 64.8 40557.6 450 7.5 78.2 63.7 44892 480 8 77.6 62.9 45511.2 510 8.5 77.7 62.3 47678.4 540 9 77.6 61.9 48607.2 570 9.5 77.1 61.3 48916.8 600 10 76.7 60.8 49226.4

11" Rad Dis 0 0 0 0 0 0 0 0 0 0 0 11 0 2 237991.7 475983.3

630 660 690 720 750 780 810 840 870 900 930 960 990 1020 1050 1080 1110 1140 1170 1200 1230 1260 1290 1320 1350 1380 1410 1440 1470 1500

10.5 11 11.5 12 12.5 13 13.5 14 14.5 15 15.5 16 16.5 17 17.5 18 18.5 19 19.5 20 20.5 21 21.5 22 22.5 23 23.5 24 24.5 25

76.1 75.5 74.7 74.3 74.1 73.4 72.9 72.5 72.1 71.8 71.6 71.4 70.5 70.5 70 69.6 68.9 68.7 68.3 67.8 67.1 66.6 66.5 66.2 66.2 66 66 65.3 65.2 64.7

60.4 60.1 59.7 59.3 59.1 58.8 58.6 58.3 57.9 57.7 57.5 57.2 57 57 56.7 56.5 56.2 56 56 55.7 55.4 55.4 55.4 55.7 55.4 55.2 55.1 55 55 54.8

48607.2 47678.4 46440 46440 46440 45201.6 44272.8 43963.2 43963.2 43653.6 43653.6 43963.2 41796 41796 41176.8 40557.6 39319.2 39319.2 38080.8 37461.6 36223.2 34675.2 34365.6 32508 33436.8 33436.8 33746.4 31888.8 31579.2 30650.4

Ambient Air Dry Bulb (F) Wet Bulb (F) Rel Humidity

44 38

45 40

44 39

48 42

CT Air Dry Bulb (F) Wet Bulb (F) Rel Humidity

52 52

48 50

48 47

48 46

Information obtained from the psychrometric chart Ambient Air CT Air lbH2O/lbDryAir 0.004 lbH2O/lbDryAir Btu/lbDryAir 15.21 Btu/lbDryAir ft^3/lbDryAir

0.0072 19.64 12.97

118041.4 Mass Flow Rate (lb/hr) 9101.1 Loss of water at steady state (lbH2O/hr) 29.1 Heat transferred from the water to the air (Btu/hr) 40317.9 Mass Flow Rate of Water into the top of the Cooling Tower (lb/hr) 5 gallons of water = 43 lbs Approximately 50 seconds to fill a 5 gallon bucket Mass Flow Rate (lb/sec) 0.86 Mass Flow Rate (lb/hr) 3096

46 41 62%

45.4 40

Velocity Profile 500000 400000 Velocity

49 48.75 98%

300000 200000 100000 0 0

3

6

Radial Distance (inch

Tower (lb/hr)

Cold Water Supply and Return Temps (F)

Temperature (F)

110 100 90 80 70 60 50

0

5

10

15

Time (min)

Dh(Btu/hr) 60000 r)

30000

20

25

Dh(Btu/hr) 60000 Dh (Btu/hr)

30000 0 -30000

0

5

10

-60000 -90000 -120000 Time (min)

15

20

25

Velocity Profile

000

000

000

000

000 0 0

3

6

Radial Distance (inches)

n Temps (F)

20

25

9

12

15

20

25