In Section 5–3 we considered one-dimensional heat conduction and assumed
heat conduction in other directions to be negligible.
Many heat transfer problems encountered in practice can be approximated as being one-dimensional,but this is not always the case.
Sometimes we need to consider heat transfer in other directions as well when the variation of temperature in other directions is significant.
In this section we will consider the numerical formulation and solution of two-dimensional steady heat conduction in rectangular coordinates using the finite difference method.
The approach presented below can be extended to three-dimensional cases.