Science & Environment
Heat Exchanger Effectiveness-NTU Calculator
Determine heat exchanger effectiveness and NTU from capacity rates and UA value.
Your inputs
Change any value to update the result instantly.
Effectiveness
67.4 %
NTU
1.667
Capacity ratio (Cr)
0.75
Cmin
3,000 BTU/hr·°F
Formula and working
NTU = UA ÷ Cmin; ε = (1 − e^(−NTU(1−Cr))) ÷ (1 − Cr·e^(−NTU(1−Cr)))
- 1
Collect the inputs
UA (overall conductance) = 5,000 BTU/hr·°F; Hot fluid capacity rate = 3,000 BTU/hr·°F; Cold fluid capacity rate = 4,000 BTU/hr·°F
- 2
Apply the formula
NTU = UA ÷ Cmin; ε = (1 − e^(−NTU(1−Cr))) ÷ (1 − Cr·e^(−NTU(1−Cr)))
- 3
Result
Effectiveness = 67.4 %
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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