TLM for diffusion: the artefact of the standard initial conditions and itselimination within an abstract TLM suite

We demonstrate both analytically and numerically, that for the TLM algorith m for numerically solving the diffusion equation the standard initial condi tions for the incident voltage pulses in terms of the initial concentration (or temperature) distribution introduce a significant numerical error. We discover the origin of this error and present an alternative prescription f or computing the node voltages at the first time step which removes this ar tefact and exhibits distinctly improved numerical accuracy. For this, we in troduce the term abstract TLM suite (ATS). An ATS is a numerical scheme whi ch formally parallels a TLM scheme, but the scattering coefficients, rho, a nd tau, may assume values outside the interval [-1, 1] or may not correspon d to the values of a real TLM network. Copyright (C) 2001 John Wiley & Sons , Ltd.