Double Diffusive Natural Convection in Hydrothermal Systems: Numerical Simulation by Lattice Boltzmann Method

The double diffusive natural convection of ore-forming fluid in hydrothermal system is numerically simulated in two dimensions by lattice Boltzmann method (LBM). A buoyancy force proportional to the temperature and concentration is applied to the fluid in a rectangular enclosures according to the Boussinesq approximation. The non-equilibrium extrapolation boundary condition is employed in the horizontal direction, while the isothermal and isoconcentrations boundary conditions are imposed in the vertical direction. The temperature field and concentration field are passively advected by the fluid flow, which obey the same equations as those of the multicomponent mixtures within the lattice Boltzmann framework. The enrichment region of the ore-forming fluid is found to focus on the top of the uplift zone. The results are in agreement with those of the previous studies. The LBM provides an alternative to the numerical simulations of the enrichment of ore-forming elements in hydrothermal systems.