Numerical investigations of diffusion coefficients in the context of multi-component gas transport within the Theory of Porous Media

In order to simulate methane oxidation within landfill covers in changing environmental conditions, a computational approach via the extended Theory of Porous Media (eTPM) was created. Its purpose is to gain an overall view on the ongoing processes such as concentration progression of methane, oxygen, carbon dioxide and nitrogen. For that, advective and diffusive transport mechanisms as well as energy production from the exothermic oxidation reaction are considered. Regarding the diffusive gas transport different approaches to model the diffusion coefficient are made use of.