# Heat Transfer Coefficient of a Pipe Wall

Written by Jerry Ratzlaff on . Posted in Thermodynamics

The resistance to the flow of heat by the pipe wall material can be expressed by the heat transfer coefficient of the pipe wall.

## Heat Transfer Coefficient of a Pipe Wall FormulA

 $$\large{ h_{wall} = \frac{ 2 \; k }{ d_i \; ln \; \left( \frac{ p_o }{ P_i } \right) } }$$

### Where:

 Units English Metric $$\large{ h_{wall} }$$ = heat transfer coefficient of a wall $$\large{\frac{Btu-ft}{hr-ft^2-F}}$$ $$\large{\frac{W}{m-K}}$$ $$\large{ ln }$$ = natural logarithm $$\large{dimensionless}$$ $$\large{ p_i }$$ = pipe ID $$\large{in}$$ $$\large{mm}$$ $$\large{ p_o }$$ = pipe OD $$\large{in}$$ $$\large{mm}$$ $$\large{ k }$$ = thermal conductivity $$\large{\frac{Btu-ft}{hr-ft^2-F}}$$ $$\large{\frac{W}{m-K}}$$