John Bell, Lawrence Berkeley National Laboratory
Modeling Electrolytes at the Mesoscale
At small scales, the standard deterministic equations used for modeling fluids break down and thermal fluctuations play an important role in the dynamics. Landau and Lifshitz proposed a modified verion of the Navier-Stokes equations, referred to as the fluctuating hydrodynamics equations that incorporate stochastic flux terms designed to incorporate the effect of fluctuations. These stochastic fluxes are constructed so that the equations are consistent with equilibrium fluctuations from statistical mechanics. In this talk, we present a generalization of fluctuating hydrodynamics to electrolytes. We then discuss some of the properties of the resulting system and show how fluctuations naturally incorporate some of the distinguishing characteristics of electrolytes. We then introduce a finite-volume method for solving the fluctuating hydrodynamics equations and present numerical results illustrating the behavior of electrolytes in some canonical flows.