title: Analytical solution for compositional profile driven by gravitational segregation and diffusion.
abstract: An alternative analytical solution is presented, based on irreversible thermodynamics, that describes the equilibrium distribution of the components of a nonideal fluid mixture in a one-dimensional hydrostatic and isothermal system. In such a system, the vertical compositional profile of the fluid at equilibrium will be determined by the interaction of gravitational and chemical potentials. Our alternative analytical solution estimates this profile from the overall composition of the fluid. It is thus more general than the existing solution, which requires knowledge of the fluid composition at a given depth and assumes that the vertical compositional profile of this fluid is already at equilibrium. The solution is demonstrated by comparison against results obtained from previously published molecular dynamics simulations of segregation in a binary mixture and against numerical simulations of a real hydrocarbon reservoir system.
authors.affiliation: Department of Earth Science and Engineering, Imperial College London, London SW7 2AZ, United Kingdom.
authors.forename: O
authors.initials: O
authors.lastname: Obidi
authors.affiliation: Department of Earth Science and Engineering, Imperial College London, London SW7 2AZ, United Kingdom.
authors.forename: A H
authors.initials: AH
authors.lastname: Muggeridge
authors.affiliation: Department of Earth Science and Engineering, Imperial College London, London SW7 2AZ, United Kingdom.
authors.forename: V
authors.initials: V
authors.lastname: Vesovic