## Log Mean Temperature Difference for Counter Current Flow Solution

STEP 0: Pre-Calculation Summary
Formula Used
Log Mean Temperature Difference = ((Outlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid)-(Inlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid))/ln((Outlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid)/(Inlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid))
LMTD = ((Tho-Tci)-(Thi-Tco))/ln((Tho-Tci)/(Thi-Tco))
This formula uses 1 Functions, 5 Variables
Functions Used
ln - Natural logarithm function (base e), ln(Number)
Variables Used
Log Mean Temperature Difference - (Measured in Kelvin) - The log mean temperature difference (LMTD) is used to determine the temperature driving force for heat transfer in flow systems, most notably in heat exchangers. The LMTD is a logarithmic average of the temperature difference between the hot and cold streams at each end of the exchanger.
Outlet Temperature of Hot Fluid - (Measured in Kelvin) - Outlet Temperature of Hot Fluid is the temperature at which the hot fluid exits the heat exchanger.
Inlet Temperature of Cold Fluid - (Measured in Kelvin) - Inlet Temperature of Cold Fluid is the temperature at which the cold fluid enters the heat exchanger.
Inlet Temperature of Hot Fluid - (Measured in Kelvin) - Inlet Temperature of Hot Fluid is the temperature at which the hot fluid enters the heat exchanger.
Outlet Temperature of Cold Fluid - (Measured in Kelvin) - Outlet Temperature of Cold Fluid is the temperature at which the cold fluid exits the heat exchanger.
STEP 1: Convert Input(s) to Base Unit
Outlet Temperature of Hot Fluid: 20 Kelvin --> 20 Kelvin No Conversion Required
Inlet Temperature of Cold Fluid: 5 Kelvin --> 5 Kelvin No Conversion Required
Inlet Temperature of Hot Fluid: 35 Kelvin --> 35 Kelvin No Conversion Required
Outlet Temperature of Cold Fluid: 10 Kelvin --> 10 Kelvin No Conversion Required
STEP 2: Evaluate Formula
Substituting Input Values in Formula
LMTD = ((Tho-Tci)-(Thi-Tco))/ln((Tho-Tci)/(Thi-Tco)) --> ((20-5)-(35-10))/ln((20-5)/(35-10))
Evaluating ... ...
LMTD = 19.5761518897122
STEP 3: Convert Result to Output's Unit
19.5761518897122 Kelvin --> No Conversion Required
19.5761518897122 Kelvin <-- Log Mean Temperature Difference
(Calculation completed in 00.016 seconds)
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Created by Ishan Gupta
Birla Institute of Technology & Science (BITS), Pilani
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Log Mean Temperature Difference for Counter Current Flow
Log Mean Temperature Difference = ((Outlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid)-(Inlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid))/ln((Outlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid)/(Inlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid)) Go
Log Mean Temperature Difference for CoCurrent Flow
Log Mean Temperature Difference = ((Outlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid)-(Inlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid))/ln((Outlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid)/(Inlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid)) Go
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## Log Mean Temperature Difference for Counter Current Flow Formula

Log Mean Temperature Difference = ((Outlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid)-(Inlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid))/ln((Outlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid)/(Inlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid))
LMTD = ((Tho-Tci)-(Thi-Tco))/ln((Tho-Tci)/(Thi-Tco))

## Log Mean Temperature Difference for Counter Current Flow

The Log Mean Temperature Difference for Counter Current Flow in is used to determine the temperature driving force for heat transfer in flow systems, most notably in heat exchangers. The LMTD is a logarithmic average of the temperature difference between the hot and cold streams at each end of the exchanger.

## How to Calculate Log Mean Temperature Difference for Counter Current Flow?

Log Mean Temperature Difference for Counter Current Flow calculator uses Log Mean Temperature Difference = ((Outlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid)-(Inlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid))/ln((Outlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid)/(Inlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid)) to calculate the Log Mean Temperature Difference, The Log Mean Temperature Difference for Counter Current Flow in is used to determine the temperature driving force for heat transfer in flow systems, most notably in heat exchangers. The LMTD is a logarithmic average of the temperature difference between the hot and cold streams at each end of the exchanger. Log Mean Temperature Difference is denoted by LMTD symbol.

How to calculate Log Mean Temperature Difference for Counter Current Flow using this online calculator? To use this online calculator for Log Mean Temperature Difference for Counter Current Flow, enter Outlet Temperature of Hot Fluid (Tho), Inlet Temperature of Cold Fluid (Tci), Inlet Temperature of Hot Fluid (Thi) & Outlet Temperature of Cold Fluid (Tco) and hit the calculate button. Here is how the Log Mean Temperature Difference for Counter Current Flow calculation can be explained with given input values -> 19.57615 = ((20-5)-(35-10))/ln((20-5)/(35-10)).

### FAQ

What is Log Mean Temperature Difference for Counter Current Flow?
The Log Mean Temperature Difference for Counter Current Flow in is used to determine the temperature driving force for heat transfer in flow systems, most notably in heat exchangers. The LMTD is a logarithmic average of the temperature difference between the hot and cold streams at each end of the exchanger and is represented as LMTD = ((Tho-Tci)-(Thi-Tco))/ln((Tho-Tci)/(Thi-Tco)) or Log Mean Temperature Difference = ((Outlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid)-(Inlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid))/ln((Outlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid)/(Inlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid)). Outlet Temperature of Hot Fluid is the temperature at which the hot fluid exits the heat exchanger, Inlet Temperature of Cold Fluid is the temperature at which the cold fluid enters the heat exchanger, Inlet Temperature of Hot Fluid is the temperature at which the hot fluid enters the heat exchanger & Outlet Temperature of Cold Fluid is the temperature at which the cold fluid exits the heat exchanger.
How to calculate Log Mean Temperature Difference for Counter Current Flow?
The Log Mean Temperature Difference for Counter Current Flow in is used to determine the temperature driving force for heat transfer in flow systems, most notably in heat exchangers. The LMTD is a logarithmic average of the temperature difference between the hot and cold streams at each end of the exchanger is calculated using Log Mean Temperature Difference = ((Outlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid)-(Inlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid))/ln((Outlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid)/(Inlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid)). To calculate Log Mean Temperature Difference for Counter Current Flow, you need Outlet Temperature of Hot Fluid (Tho), Inlet Temperature of Cold Fluid (Tci), Inlet Temperature of Hot Fluid (Thi) & Outlet Temperature of Cold Fluid (Tco). With our tool, you need to enter the respective value for Outlet Temperature of Hot Fluid, Inlet Temperature of Cold Fluid, Inlet Temperature of Hot Fluid & Outlet Temperature of Cold Fluid and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well.
How many ways are there to calculate Log Mean Temperature Difference?
In this formula, Log Mean Temperature Difference uses Outlet Temperature of Hot Fluid, Inlet Temperature of Cold Fluid, Inlet Temperature of Hot Fluid & Outlet Temperature of Cold Fluid. We can use 1 other way(s) to calculate the same, which is/are as follows -
• Log Mean Temperature Difference = ((Outlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid)-(Inlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid))/ln((Outlet Temperature of Hot Fluid-Outlet Temperature of Cold Fluid)/(Inlet Temperature of Hot Fluid-Inlet Temperature of Cold Fluid)) Let Others Know