MODELING OF VISCOSITY AND THERMAL CONDUCTIVITY OF HYDROCARBONS BASED ON EQUATION OF STATE

Abstract

Based on the geometric similarity of P-V-T, T-μ-P and T-λ-P diagrams, viscosity (μ) and thermal conductivity (λ) models can be derived from an equation of state (EOS). The advantages of an EOS-based viscosity / thermal conductivity model are simple in form, applicable to both gas / liquid, high-pressure / low-pressure, and smooth phase transition of μ / λ in the near-critical region could be achieved. In this work, a modified version of the viscosity model based on Peng-Robinson (PR) EOS, and a newly established thermal conductivity model based on PR EOS were developed. Simple mixing rules were used for extension to mixtures. Extensive tests have been performed on pure hydrocarbons, carbon dioxide and nitrogen, hydrocarbon mixtures containing defined components as well as complex reservoir fluids. The comparison with those typical viscosity / thermal conductivity correlations currently adapted in the petroleum industry shows the superiority of the proposed models.