PNNL

Abstract

A numerical model based on smoothed particle hydrodynamics (SPH) for reactive transport and mineral precipitation in fractured and porous materials was developed. Because of its Lagrangian particle nature, SPH has several advantages for modeling Navier-Stokes flow and reactive transport including: i) in a Lagrangian framework there is no non-linear term in the momentum conservation equation, so that SPH allows accurate solution of momentum dominated flows; ii) complicated physical and chemical processes such as surface growth due to precipitation/ dissolution and chemical reactions are easy to implement. In addition, SPH simulations explicitly conserve mass and linear momentum. The SPH solution of the diffusion equation with fixed and moving reactive solid-fluid boundaries was compared with analytical solutions and the Lattice Boltzmann simulations of Kang et al [12]. To illustrate the capabilities of the model, coupled three-dimensional flow, reactive transport and precipitation in a fracture aperture with complex geometry were simulated.