Science & Environment
Cooling Tower Evaporation & Blowdown Calculator
Estimate evaporation, drift and blowdown water losses in a cooling tower from circulation rate and cycles of concentration.
Your inputs
Change any value to update the result instantly.
Blowdown rate
2.83 gpm
Evaporation loss
8.5 gpm
Drift loss
0.2 gpm
Total makeup water
11.53 gpm
Formula and working
E = R × ΔT × 0.00085; D = E ÷ (COC − 1); Drift = R × driftRate
- 1
Collect the inputs
Circulation flow rate = 1,000 gpm; Range (ΔT) = 10 °F; Cycles of concentration = 4; Drift loss = 0.02 %
- 2
Apply the formula
E = R × ΔT × 0.00085; D = E ÷ (COC − 1); Drift = R × driftRate
- 3
Result
Blowdown rate = 2.83 gpm
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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