Nonisothermal Multicomponent Reactive Transport Model for Unsaturated Soil

Abstract

A multicomponent reactive transport model, coupled with an existing thermal, hydraulic, and mechanical model for porous media, is investigated. The model is based on conservation of mass/energy principles for the flow and stress-strain equilibrium for the mechanical behavior. The resultant model is coupled with a geochemical model to capture geochemical interactions. Numerically, the Galerkin FEM is employed for spatial discretization and an implicit Euler method for temporal discretization. The coupling of the transport and geochemical models is achieved through both noniterative and iterative approaches. A series of applications are considered to demonstrate the numerical performance and qualitative behavior, specifically in the context of multicomponent behavior. The model shows good convergence and computational efficiency.

An analytical model for chemical diffusion in layered contaminated sediment systems with bioreactive caps

“…Praveen Kumar and Dodagoudar provide an accurate methodology for numerical simulation of the two‐dimensional contaminant transport through the saturated homogeneous porous media and landfill liners using element‐free Galerkin method (EFGM). The finite element method–based numerical model COMPASS has also been used for the analysis of contaminant diffusion in the layered porous media . Zhang et al investigated contaminant transport in the two‐layered system consisting of compacted clay liner and the aquifer using the numerical method including the finite‐difference method and the numerical inversion of Laplace transform.…”

Diffusive Reactive Transport of Multicomponent Chemicals Under Coupled Thermal, Hydraulic, Chemical and Mechanical Conditions

“…The chemical module of the coupled model included multicomponent reactive chemical transport incorporating an equilibrium geochemical model. The model was employed for the numerical simulation of chemical behaviour under THCM conditions in compacted clays Seetharam et al 2007Seetharam et al , 2011.…”

Simulation of repository gas migration in a bentonite buffer

“…The formulation for moisture and deformation follows that of Thomas and He (1998), with the dissolved chemical behaviour following the work of Seetharam et al (2011). Therefore, only the gas migration equation is described here in detail.…”

“…The initial thermo-hydro-mechanical model was presented by Thomas and He (1998) and extension into chemical transport and reaction behaviour is described by Seetharam et al (2011). Part of this work was initially presented in a report for the Nuclear Decommissioning Authority (Vardon et al, 2010).…”