Soret Effect for a Ternary Mixture in Porous Cavity: Modeling With Variable Diffusion Coefficients and Viscosity

Abstract

A porous cavity filled with methane (C1), n-butane (nC4), and dodecane (C12) at a pressure of 35.0MPa is used to investigate numerically the flow interaction due to the presence of thermodiffusion and buoyancy forces. A lateral heating condition is applied with the left wall maintained at 10°C and the right wall at 50°C. The molecular diffusion and thermal diffusion coefficients are functions of temperature, concentration, and viscosity of mixture components. It has been found that for permeability below 200md the thermodiffusion is dominant; and above this level, buoyancy convection becomes the dominant mechanism. The variation of viscosity plays an important role on the molecular and thermal diffusion.