Science & Environment
Heat Exchanger LMTD Calculator
Compute the log mean temperature difference for counter-flow or parallel-flow heat exchangers.
Your inputs
Change any value to update the result instantly.
LMTD
69.52 °F
ΔT1
80 °F
ΔT2
60 °F
Flow type
1
Formula and working
LMTD = (ΔT1 − ΔT2) ÷ ln(ΔT1 ÷ ΔT2)
- 1
Collect the inputs
Hot fluid inlet temp = 200 °F; Hot fluid outlet temp = 140 °F; Cold fluid inlet temp = 80 °F; Cold fluid outlet temp = 120 °F; Flow arrangement = 1
- 2
Apply the formula
LMTD = (ΔT1 − ΔT2) ÷ ln(ΔT1 ÷ ΔT2)
- 3
Result
LMTD = 69.52 °F
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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