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FIRST METHOD

Input parametersHot water temperature 40.5 C

Cold water temperature 29.5 C

Wet bulb temperature 26 C

Range of cooling tower 11 C

Approach 3.5 C

Diameter of fan 3.8 m

Diameter of fan hood 3.9 m

Avarage air velocity at exit 6 m/s

Density of water 1000 Kg/m^3

Density of air 1.2 Kg/m^3

Specific heat capacity of water 4.178 kj/kgK

Air mass flow rate of fan hood (G) 86.1202368 kg/s

Water mass flow rate( L) 111 kg/s/cell

Water mass flow rate/air mass flow rate 1.288895666

Enthalpy pick up water

(H2-H1) = L/G(t2-t1)[1+0.0008(t2-32)]

H2-H1 26.6042295 BTU/lb of a

Heat balance calculation

G(H2-H1) = L(T1-T2)+Ev x cold water temperature

Heat removing capacity of water = Heat rejection rate in the process

Heat removing capacity of the tower 1260.139399 Kcal/sec

Heat rejection rate in the process 18184118.35 BTU/Hr

Is almost equal Hence Heat balance is establishedOther ParametersAir flow calculation 71.766864 m^3/sec

Approach 3.5 C

Range 11 C

Drift loss 0.3996 m^3/hr

Evaporation loss 6.725268 m^3/hr

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Dry bulb teperature 30 C

Wet bulb temerature 26 C

Relative humidity 72 %

If fan RPM reduced to 50%(an approximately 40% reduction in air flow rate)

0.1 bar at

45.8 C

29.5 C

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COOLING TOWER DESIGN

Second me

104.9 F Estimate outlet85.1 F Enthalpy of air outlet

78.8 F Enthapy of air inlet at

19.8 F

6.3 F

L/G

Air mass flow rate

Calculate towedelta ha

1 BTU/Lb F

T has

85.1 53.1

87.08 55.13

71.766864 m^3/sec 95 63.04

880966.3645 lb/hr/cell 0.111 m^3/sec/cell 399.6 m^3/hr/cell 96.98 64.83

102.92 70.94

104.9 73.02

ir 14.63233 Kcal/kg of air

(Ka*V)/L

Determine the loading

Ka

4536501.837 Kcal/Hr

4580579.413 Kcal/Hr

This Tower characteristic Graph

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86 F

78.8 F

Determine

40.5 C

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hod

air temperature 35 C 95 Ft 37.5 C or 99.5 F saturated 145 kj/kg 62.35 BTU/lb

et bulb tem 26 C or 78.8 F 80 kj/kg 34.4 BTU/lb

1.411616

78.63327 Kg/s

characteristic by the simpsion rule13 kj/kg 5.59 BTU/lb

ha has-ha 1/(has-ha)

34.4 18.7 0.053476

37.195 17.935 0.055757

48.375 14.665 0.06819

51.17 13.66 0.073206

59.555 11.385 0.087835

62.35 10.67 0.093721

0.071247

1.41069

factor as per graph 2.5 GPM/ft^2 1111.5 lbs/hr/ft^2

100

cooling water temperature 10F above wet bulb temperature

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the tower dimentions

Tower hight 15.67981 ft 4.779207 m

Area of tower 121345.6 ft^2 11273 m^2