Известия Томского политехнического университета: Инжиниринг георесурсов (Apr 2023)
SIMULATION OF THERMAL PROCESSES IN A SUBMERSIBLE MOTOR OF AN ELECTRIC CENTRIFUGAL PUMP OPERATING IN A PERIODIC MODE
Abstract
Relevance. Today, one of the important trends in the Russian oil and gas industry is the increase in the fund of low-yield wells, in this regard, the improvement of technologies for mechanized production of low-yield wells is relevant. Installations of electric centrifugal pumps have become widespread in mechanized oil production, however, the operation of low-flow wells by electric centrifugal installations is accompanied by a number of complications, in particular, insufficient heat removal from the submersible engine by the flow in the well. A promising method of increasing the efficiency of electric-centric installations in low-flow wells is the implementation of a periodic short-term pumping mode. Object: thermal processes in the «submersible engine – borehole fluid» system of an electric centrifugal pump installation operating in a periodic short-term mode. The purpose of the research is to study the formation of a temperature field in a submersible electric motor and the fluid flowing around it during operation of an electric centrifugal pump in a periodic short-term mode. Methods: modeling of thermal processes in a well based on the numerical solution of the system of heat transfer equations in the «submersible engine – borehole fluid» system. Results. Based on the simulation results, it is shown that the temperature of the submersible electric motor and the liquid reaches maximum values at the initial stage during the well commissioning, during further operation of the well in a periodic short-term mode, the temperature of the submersible motor and the borehole fluid decreases significantly (the heating of the submersible motor and the liquid relative to the initial temperature decreases by more than 2 times). The influence of the power of the submersible engine (after the output of the well to the mode) on the thermal field in the well was investigated and it was found that with an increase in power, the heating of the submersible engine and the liquid increases in proportion to the degree of growth in power. The influence of the duration of pumping and accumulation periods on the temperature of the submersible engine and liquid (after the well is put into operation) has been studied. It is established that with an increase in the duration of the pumping period, the temperature of the submersible engine and the liquid grows, as a result, from the point of view of reducing the amplitude temperature of the electric centrifugal pump installation nodes in the periodic short-term mode, it is necessary to set the shortest possible periods of pumping and accumulation cycles. The results of numerical calculations are compared with experimental data and it is shown that the proposed model can be used to calculate the thermal regime of a submersible engine during operation of an electric center installation in a periodic short-term mode.
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