Transient heating of buried cables

The paper develops exact methods of computing the thermal performance of buried cables, based on a solution of the relevant differential equations given by Jaeger in 1956. The approach differs from that of other workers, who have used approximate methods of calculation. It is shown that the integrals occurring in the exact solution only require a small amount of computation, and if there is very great demand for this information, it could easily be codified by one of the national computing organizations. The results obtained by the exact method are compared with those of other workers, particularly Whitehead and Hutchings (1938), and it is shown that, although their methods are generally satisfactory, they can lead to large discrepancies in particular cases, especially for small heating times. Calculations are made for a particular cable to show the application of the method.