Logarithmic Mean Temperature Differential Formula
|
\( LMTD \;=\; \dfrac{ \Delta T_a - \Delta T_b }{ ln \cdot \dfrac{ \Delta T_a }{ \Delta T_b } }\) |
Symbol |
English |
Metric |
\( LMTD \) = logarithmic mean temperature differential |
\(Btu \;/\; lbm\) |
\(J \;/\; kg\) |
\( ln \) = natural logarithm |
\(dimensionless\) |
\(dimensionless\) |
\( \Delta T_a \) = temperature differential |
\(F\) |
\(K\) |
\( \Delta T_b \) = temperature differential |
\(F\) |
\(K\) |
Logarithmic mean temperature differential, abbreviated as LMTD, also called log mean temperature differential, is used to determine the temperature driving force for heat transfer usually in heat exchangers.
