Coupling Multiphysics with Geochemistry: The COMSOL-PhreeqC Interface
Phreeqc is a program for simulating chemical reactions and 1D transport processes in aqueous systems. Several couplings between conservative transport codes and PHREEQC already exist. The methodology used here is based on the operator splitting concept: the transport of the aqueous components and the chemical reactions are solved in two different steps. The Java interface uses the COMSOL Java API and the IPhreeqc dynamic library. Our approach combines the key strengths of both codes: the flexibility of COMSOL for solving all kind of PDE systems and the wide range of chemical capabilities of Phreeqc. This has been achieved with enough performance to face highly coupled non-linear Thermal Hydraulic Mechanical and Chemistry in 3D problems (THMC).