Chapter 2, Problem 156P

Consider a water pipe of length $L=17\text{ m}$, inner radius $r_1=15\text{ cm}$, outer radius $r_2=20\text{ cm}$ and and thermal conductivity $k=14\text{ W/m}\text{.K}\text{.}$

Heat is generated in the pipe material uniformly by a 25-kW electric resistance heater. The inner and outer surfaces of the pipe are at $T_1={60}^o\text{C }$ and $T_2={80}^o\text{C,}$ respectively. Obtain a general relation for temperature distribution inside the pipe under steady conditions and determine the temperature at the center plane of the pipe.