Cooling Tower Calculator — Formula
## Cooling Tower Water Balance
Cooling towers reject heat through evaporation, requiring continuous makeup water.
### Formulas
**Heat rejected = m_dot cp delta_T**
**Evaporation rate = 0.00085 x Circulation (m^3/h) x Range (deg C)**
The 0.00085 factor is an approximation for the fraction evaporated per degree of cooling. Blowdown removes concentrated water to limit mineral buildup: **Blowdown = Evaporation / (Cycles - 1)**
**Makeup = Evaporation + Blowdown**
Cooling towers reject heat through evaporation, requiring continuous makeup water.
### Formulas
**Heat rejected = m_dot cp delta_T**
**Evaporation rate = 0.00085 x Circulation (m^3/h) x Range (deg C)**
The 0.00085 factor is an approximation for the fraction evaporated per degree of cooling. Blowdown removes concentrated water to limit mineral buildup: **Blowdown = Evaporation / (Cycles - 1)**
**Makeup = Evaporation + Blowdown**
Esempio Risolto
50 L/s circulation, 8 deg C range, 4 cycles of concentration.
- Heat rejected = 50 x 4.18 x 8 = 1672 kW
- Circulation = 50 x 3.6 = 180 m^3/h
- Evaporation = 180 x 8 x 0.00085 = 1.224 m^3/h
- Blowdown = 1.224 / (4-1) = 0.408 m^3/h
- Makeup = 1.224 + 0.408 = 1.632 m^3/h