DOI: 10.1615/ICHMT.2008.CHT
ISBN Print: 978-1-56700-253-9
ISSN: 2578-5486
ON THE ACCURACY OF THE INCREMENTAL UNKNOWNS IN SIMULATING TRANSIENT HEAT AND MASS TRANSFER PROBLEMS
SINOPSIS
We assess the performances of the Incremental Unknowns numerical schemes when used in solving a time dependent 2D coupled nonlinear heat and mass transfer in a homogenous porous material. The formulation of this coupled heat and mass transfer phenomena is based on the simplified model of De Vries where it is assumed that the heat transfer due to the mass transfer is negligible and that the time variation of the condensed water is also negligible. The system of equations is numerically solved when the material is subjected to ambient and initial conditions in terms of temperature and water content. The results are compared to those obtained using finite differences schemes (Crank Nicolson and Euler Implicit), and the Compact Scheme. Validation tests are performed in 1D situation and results obtained from different schemes are compared among them and against the analytical linear solution. In the 2D situation the system is solved in linear and nonlinear cases using the Incremental Unknowns and the classical finite differences. Time marching solution is achieved in all cases by using ADI method. The numerical results show clearly that either in 1D or 2D situation the Incremental Unknowns performs very well in terms of accuracy and the required CPU time.