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The article is devoted to the theoretical study of the operation process of the borehole ejection system as part of the tubing string, jet pump and packer installed below; the system implements the hydrojet method of oil well operation. The improved design of the jet pump contains inclined guiding elements placed in its receiving chamber for swirling the injected flow, which results in an increase in the efficiency of the borehole ejection system. Based on the law of conservation of liquid momentum in the mixing chamber of the jet pump and taking into account the inertial pressure component caused by the swirling of the injected flow, there is obtained the relative form of the equation of the ejection system pressure characteristic, the structure of which contains a component that determines the value of the additional dynamic head. According to the results obtained, the additional dynamic head caused by swirling of the injected flow is determined by the ratio of the geometric dimensions of the flow path of the jet pump, the angle of inclination of the elements for creating vortex flows, and the ratio of the power and reservoir fluids. In the case of asymmetric swirling of the injected flow, an increase in the value of the relative displacement of the jet pump decreases the value of the additional dynamic pressure. In order to study the effect of flow swirling on the energy characteristic of the ejection system, the pressure characteristic of the jet pump was transformed into the dependence of its efficiency on the injection coefficient. Jet pump models with the ratio of the cross-sectional areas of the mixing chamber and the nozzle of 5.012 and 6.464, respectively, were used to check the adequacy of the theoretical pressure and energy characteristics obtained during the simulation of the performance process of the concentric ejection system. The average error in the theoretical determination of the pressure and efficiency of the vortex jet does not exceed 8.65% and 6.48%, respectively.

The scope of downhole ejection systems is limited by the low value of the efficiency of the jet pump, the value of which usually does not exceed 35 %. Significant energy losses when mixing flows are the reason for the low efficiency of the jet pump. The energy performance of the downhole ejection system can be increased by creating swirling vortex circulating currents in the flow part of the jet pump. This optimizes the nature of the flow mixing and increases the energy performance of the jet pump. In the process of studying the structures, features of the working process and usage experience of ejection systems designed for drilling, operation and repair of oil and gas wells, it is established that the twisting of the working medium in downhole jet pumps can be carried out using guide elements placed at a certain angle in the oncoming flow and rotation of individual parts of the ejection system by means of an external drive and hydraulic turbines. The use of guide elements and hydraulic turbines necessitates the use of part of the energy of the working flow, which drives the downhole jet pump, to spin the working medium. In oil and gas ejection systems, the twisting of working, injected and mixed streams can be realized, as well as the combined simultaneous twisting of several streams. In the process of analyzing the experience of using vortex jet devices, it has been found that the flow twist allows to increase the injection coefficient of the jet pump by 38.1 %, efficiency – up to 70 %, vacuum in the receiving ch amber – up to 40 %. The increase in the basic geometric pa-rameter of the jet pump reduces the effect of flow twist on the characteristics of the ejection system. Flow twisting in downhole jet pumps can be recommended in the implementation of long-term processes, for example, in the ex-traction of formation fluid, when the value of the efficiency of the ejection system significantly affects the cost of oil production.

Івано-Франківський національний технічний університет нафти і газу ВИЗНАЧЕННЯ РЕЖИМУ РОБОТИ СВЕРДЛОВИННОГО СТРУМИННОГО НАСОСА Анотація. Запропонована методика розв'язку системи рівнянь, які описують напірну характеристику свердловинного струминного насоса. Відповідно до приведеного в роботі алгоритму визначення гідравлічних втрат в робочому потоці на ділянці між робочою насадкою та камерою змішування здійснюється з використанням методу послідовних наближень. Розроблена послідовність проведення розрахункових операцій та програма для їх реалізації. Приведений в роботі розрахунковий алгоритм дозволяє змінювати точність прогнозування напору, створюваного струминним насосом та тривалість процедури його визначення. Реалізація запропонованого розрахункового комплексу може здійснюватись з використанням середовища Delphi та програмних ресурсів PTC Matchad. Ключові слова: нафтогазові ежекційні технології, свердловинний струминний насос, ежекційна система, напірна характеристика, метод послідовних наближень.