Cooling Tower Approach

How close the cold water temperature gets to the ambient wet-bulb temperature. A smaller approach means a more effective (but larger) tower. Typical approach is 5 to 10 degrees F.

$$\text{Approach}=T_{\text{supply}}-T_{\text{wet bulb}}$$

Variables

Symbol	Meaning	Unit
$T_{s}upply$	Temperature of cold water supplied from the tower	degrees F
$T_{w}etbulb$	Ambient wet-bulb temperature, the lowest temperature achievable by evaporative cooling	degrees F

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Part of The Blueprint of Water