Heat Transfer by Conduction resistance through a Cylindrical Wall Formula
|
| \(\large{ R_t = \frac { ln \; \left( \frac {r_2 } { r_1 } \right) } { 2 \; \pi \; k \; l } }\) |
| Symbol |
English |
Metric |
| \(\large{ R_t }\) = thermal resistance |
\(\large{\frac{hr-F}{Btu}}\) |
\(\large{\frac{K}{W}}\) |
| \(\large{ l }\) = length of material |
\(\large{ft}\) |
\(\large{m}\) |
| \(\large{ ln }\) = natural logarithm |
\(\large{dimensionless}\) |
| \(\large{ \pi }\) = Pi |
\(\large{3.141 592 653 ...}\) |
| \(\large{ r_1 }\) = radius inside diameter (ID) |
\(\large{in}\) |
\(\large{mm}\) |
| \(\large{ r_2}\) = radius outside diameter (OD) |
\(\large{in}\) |
\(\large{mm}\) |
| \(\large{ k }\) = thermal conductivity |
\(\large{\frac{Btu-ft}{hr-ft^2-F}}\) |
\(\large{\frac{W}{m-K}}\) |
