Solution of adsorption problems involving steep moving profiles

The moving finite element collocation method proposed by Kiil et al. (1995) for solution of problems with steep gradients is further developed to solve transient problems arising in the field of adsorption. The technique is applied to a model of adsorption in solids with bidisperse pore structures. Numerical solutions were found to match the analytical solution when it exists (i.e. when the adsorption isotherm is linear).

Results of this application study show that the method is simple yet sufficiently accurate for use in adsorption problems with steep moving gradients, where global collocation methods fail or require a prohibitive number of collocation points. The technique is general in nature and may also be applied to a large variety of multiphase transient heat or mass transfer problems involving steep gradients.