We show that the general boundary condition DaWax + a@ = 0 (D is the diffusion coefficient and a is a ## constant) in TLM diffusion modelling can be expressed accurately in terms of a voltage reflection coefficient p = ( A x -a A t ) / ( A x + aAt), where Ax is the spatial resolution and At is the
Boundary conditions in TLM diffusion modelling
โ Scribed by Xiang Gui; Donard de Cogan
- Publisher
- John Wiley and Sons
- Year
- 2005
- Tongue
- English
- Weight
- 213 KB
- Volume
- 19
- Category
- Article
- ISSN
- 0894-3370
- DOI
- 10.1002/jnm.599
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โฆ Synopsis
The connection algorithms used in transmission-line matrix (TLM) modelling of diffusion processes for describing boundary conditions in both link-line and link-resistor nodal configurations have been derived. The new algorithms regarding the inhomogeneous Robin condition enhance the capability of the TLM method in simulating thermal or particle diffusion phenomena. A number of boundary treatments in the existing literature have been found to be special cases of our results. The Dirichlet-type boundary condition is also discussed. TLM numerical results using the new algorithms, particularly with the link-resistor model for achieving signal synchronization, are shown to be in excellent agreement with the available analytical solutions.
๐ SIMILAR VOLUMES
An approach of using a current-controlled voltage source analogy to account for a general boundary condition of particle or thermal flux in transmission-line matrix (TLM) diffusion modelling has been developed. For mass diffusion, this boundary condition is expressed as D aClax + a C = 0, where C is
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