# Heat Transfer by Conduction Resistance through a Cylindrical Wall

Written by Jerry Ratzlaff on . Posted in Thermodynamics

### Heat Transfer by Conduction resistance through a Cylindrical Wall Formula

$$\large{ R_t = \frac { ln \; \left( \frac {r_2 } { r_1 } \right) } { 2 \; \pi \; k \; l } }$$

Where:

$$\large{ R_t }$$ = thermal resistance

$$\large{ l }$$ = length of material

$$\large{ ln }$$ = natural logarithm

$$\large{ \pi }$$ = Pi

$$\large{ r_1 }$$ = radius inside diameter (ID)

$$\large{ r_2}$$ = radius outside diameter (OD)

$$\large{ k }$$ = thermal conductivity