CONDUCTION HEAT TRANSFER
2 p ro L
5.92 x 105
2 (3.14) (0.54 ft) (35 ft)
A 10 ft length of pipe with an inner radius of 1 in and an outer radius of 1.25 in has an
outer surface temperature of 250°F. The heat transfer rate is 30,000 Btu/hr. Find the
interior surface temperature. Assume k = 25 Btu/hr-ft-°F.
2 p k L(Th
Solving for Th:
2 p k L
hr ft °F
The evaluation of heat transfer through a cylindrical wall can be extended to include a composite
body composed of several concentric, cylindrical layers, as shown in Figure 4.