Heat Transfer
CONDUCTION HEAT TRANSFER
Q
A
(Ti
To)
(RCu
Rasb
Rfib)
500°F
(0.000347
0.2170
7.5758)hr ft2 °F
Btu
64.2
Btu
hr ft2
Conduction-Cylindrical Coordinates
Heat transfer across a rectangular solid is the most direct application of Fourier’s law. Heat
transfer across a pipe or heat exchanger tube wall is more complicated to evaluate. Across a
cylindrical wall, the heat transfer surface area is continually increasing or decreasing. Figure 3
is a cross-sectional view of a pipe constructed of a homogeneous material.
Figure 3 Cross-sectional Surface Area of a Cylindrical Pipe
Rev. 0
Page 11
HT-02
