NDC'01

STOCHASTIC MODELLING OF COUPLED TRANSPORT PROCESSES THROUGH POROUS MEDIA BY PERCOLATION THEORY

Csaba Mészáros¹, István Farkas¹ and Ágnes Bálint²
1. Department of Physics and Process Control, Szent István University
Páter K. u. 1., H-2100 Gödöll, Hungary
E-mail: csmeszaros@fft.gau.hu, ifarkas@fft.gau.hu
2. Department of Chemistry and Biochemistry, Szent István University
Páter K. u. 1., H-2100 Gödöll, Hungary
E-mail: balint@gikk.gau.hu

Keywords: coupled heat and mass transport, percolation, phase transitions

ABSTRACT

A new modelling strategy for the general problem of the coupled heat and mass transfer problem through porous media is elaborated explicitly taking into account of the thermodynamic state dependence of conductivity and coupling coefficients.
In a first approximation the general scaling relations concerning percolative systems are applied for description of discrete changes of the conductivity coefficients at fixed values of the coupling coefficients. The temperature and moisture level functions are computed in the same approximation for a sequence of values of the percolative probability. In the final step the coupled heat and moisture flow shape is refined via calculation of the relaxation rates characterizing the effects of the critical slowing down taking place at percolative phase transitions. The refinement is performed by randomization of the initial solution of the coupled systems by algorithms elaborated for applications of the Monte-Carlo methods at solving of such stochastic problems.