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TLM nodal state estimator: an alternative method of initializing a two-dimensional diffusion model

Koay, A. L.; Wilkinson, A. J.; Pulko, S. H.


A. L. Koay

A. J. Wilkinson

S. H. Pulko


The transmission line matrix (TLM) method is an established technique for modelling thermal transients in heat transfer systems. However, initial and boundary conditions have always been slightly problematic, particularly when the boundary condition is specified as a temperature (Transmission Line Matrix (TLM) Techniques for Diffusion Applications. Gordon & Breach: London, 1998), for example, when the body of interest is suddenly exposed to a different temperature on its surface. In such a case the modelled solution contains additional dynamics that are associated with the two sub-meshes in the TLM network and the two timesteps necessary for the temperature change to be fully communicated. These initialization problems are related to the fact that the boundary temperature in merely imposed as a fixed value on the network; the fundamental information-carrying quantity, on the other hand, is the pulse, the thermal state of the body being represented by the distribution of pulses. Here, we aim to provide an alternative initialization approach, using nodal state estimation to derive pulse distributions from boundary and initial conditions specified by temperature. Consideration is given to the accuracy of the estimator by comparison with the first timestep solution proposed by Enders (Int. J. Numer. Model. 2002; 15:251-259). Copyright (c) 2008 John Wiley & Sons, Ltd.


Koay, A. L., Wilkinson, A. J., & Pulko, S. H. (2008). TLM nodal state estimator: an alternative method of initializing a two-dimensional diffusion model. International journal of numerical modelling, 21(5), 351-368.

Journal Article Type Article
Acceptance Date Mar 10, 2008
Online Publication Date May 28, 2008
Publication Date 2008-09
Print ISSN 0894-3370
Publisher Wiley
Peer Reviewed Peer Reviewed
Volume 21
Issue 5
Pages 351-368
Keywords TLM; State estimator
Public URL
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