ANALYSIS OF HEAT

EXCHANGER BY LMTD METHOD

PREPARED BY:-Urvesh Dungarani 140050119506

GUIDED BY:-Chetan K Gohil

BITS EDU CAMPUS

LOGARITHMIC MEAN TEMPERATURE DIFFERENCE(LMTD)

• Defination:Logarithmic mean temperature difference is define as that temperature difference which,if constant,would give the same rate of heat transfer as actually occur under variable condition of temperature difference.

• With help of LMTD ,the value of temperature at any length of heat exchanger or vice versa is easily available.

Logarithmic mean temperature difference for “parallel flow”

And 𝟏𝑪𝒄

=𝒕𝒄 𝟐−𝒕𝒄𝟏

𝑸

∆ 𝑡𝑚=𝜃𝑚 𝑖𝑠 called the logarithmic meantemperature difference (LMTD)

Logarithmic Mean Temperature Difference for “Counter Flow”

=…………(2)

Equation (2) represents equation for LMTD for counter flow Heat exchanger.

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