SOLVING TRANSIENT DIFFUSION-PROBLEMS - TIME-DEPENDENT FUNDAMENTAL SOLUTION APPROACHES VERSUS LTDRM APPROACHES

In the literature, numerical approaches for solving transient diffusio n equations with the boundary element method in the time domain can be classified into two categories, those adopting time-independent funda mental solutions and those adopting time-dependent fundamental solutio ns. In the latter category, there are traditionally two schemes in ter ms for time integration, both of which require a reasonable time-step size to obtain a certain degree of accuracy, although one scheme allow s a larger time step than the other. Few people seem to have realized that there is a connection between time-dependent fundamental solution approaches and the so-called LTDRM (Laplace Transform Dual Reciprocit y Method) approach through the Laplace transformation. Such a connecti on is established here with a brief discussion of the advantages and d isadvantages of each approach under different circumstances. (C) 1998 Elsevier Science Ltd. All rights reserved.