Link for citation: Kostarev N.A., Trufanova N.M. Numerical simulation application to analyzing heating cable efficiency during mining high viscous oil. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 1, рр. 99-110. In Rus.

The relevance of the study is caused by noticeable increase in hard-to-recover oil reserves in recent years, associated with the steady depletion of light, low-viscosity carbon deposits. Heavy, high-viscosity oils and natural bitumens are characterized by high content of asphaltenes, resins and paraffins, which leads to technological difficulties and a number of complications in fluid extraction and transportation. To solve the problems associated with the production of hard-to-recover oil, it is necessary to apply additional technological operations aimed at reducing the viscosity of the fluid, which leads to an increase in the cost of produced raw materials. One of such methods can be heating the wellbore with a heating cable in order to maintain the required temperature of the flow and maintain oil fluidity. The main disadvantage of this method is high energy consumption, which can be reduced using mathematical modeling methods for heat and mass transfer in an oil well, which allow evaluating the thermal effect of the heating cable and determining the required technological characteristics of the equipment for trouble-free operation of the well. The aim of the research is to study the effect of the heating cable on operation of wells with high-viscosity oil, as well as to determine the necessary technological parameters of heating at which oil retains its fluidity and ensures normal operation of downhole pumping equipment. Object: a vertical section of an oil well, where a heating cable is used to reduce the viscosity of the fluid, located in one of the fields in the Republic of South Sudan. Methods: experimental determination of the rheological and thermophysical properties of oil using laboratory equipment, methods of differential scanning calorimetry and rheometry, the results of which were used as input data for mathematical modeling of heat and mass transfer in an oil well with a heating cable in order to assess the thermal effect of its operation. Numerical modeling of partial differential equations was carried out using the finite volume method in the Ansys Fluent software package. Results and conclusions. The fields of temperatures, static pressure and velocities in an oil well were obtained taking into account the rheological and thermophysical properties of the extracted raw materials during heating cable operation with different power and without it. It is shown that the presence of a heating cable in the well has a favorable effect on the performance, leads to decrease in oil viscosity by several orders of magnitude, decrease in the pressure drop in the lift pipes by several MPa due to decrease in viscous friction losses and increase in the average flow rate. It was found that the production efficiency in the well under consideration can be increased by replacing the heating cable with a high-temperature cable of greater length, which will lead to increase in the flow rate and the overhaul period of the electric submersible pump, by maintaining oil viscosity above the critical value throughout the entire section of the well.