Numerical modelling of heat transfer in spherical domains by means of the bem using discretisation in time

A combined variant of the BEM called in literature the BEM using discretization in time consists in an approximation of the time derivative
appearing in Fourier's equation by an adequate differential quotient. The next steps of mathematical manipulations and also the numerical algorithm are
similar to a typical boundary element approach. In the paper the method is applied to numerical computations concerning a non-steady heat diffusion in
homogeneous and non-homogeneous spherical domains. In the final part of the paper the results of computations are presented.