Investigation of the temperature distribution in a heterogeneous reservoir during fluid filtration, taking into account thermodynamic effects

Abstract

The purpose of the work is to study the temperature field in a formation with heterogeneous permeability during non-stationary non-isothermal two-phase filtration of oil and water, taking into account Joule–Thomson and adiabatic effects. The novelty of the study lies in the establishment of patterns of temperature distribution during two-phase filtration in a formation with heterogeneous permeability, non-monotonic temperature changes associated with two-phase filtration. Numerical experiments have shown that during non-stationary two-phase non-isothermal filtration of water and oil in the bottomhole region of the formation in its heterogeneous zone, temperature formation occurs at different rates in the angular distribution at the initial moments of well operation. In this case, depending on the ratio of the permeabilities of the formation and the heterogeneity zone and on the initial water saturation of the formation, during two-phase filtration in the heterogeneity region relative to the homogeneous one, either a decrease in temperature or, vice versa, an increase in temperature can be observed. The results obtained can be used when interpreting temperature measurement data using multi-sensor borehole equipment in formations with heterogeneous permeability in the presence of multiphase flows, and solving problems of the ecology of freshwater horizons.