Nowadays the most actual problems for oil producing from marginal wells are under-stream period increasing and specific energy consumption decreasing to raise fluid to the surface. The hydro jet method of the well operating allows solving the above oil production tasks. Despite of the advantages of the hydro jet method of operation, such as the fluid production with high gas content and mechanical impurities, the ability to drain formations with a low inflow, one of the problems is the lack of a simple engineering technique for calculating the hydraulic jet pumps (HJP) characteristics adapted for downhole conditions.
In this article we present testing industrial HJP results with different values of the basic geometric parameter in a wide range of the active (7.2-13.1 MPa) and the passive (0.2-3.1 MPa) flow pressures simulating downhole conditions. 120 characteristics of the hydraulic jet pump operation were obtained. Based on the results of processing the experimental data, the influence of the above parameters on the HJP characteristics was determined: 1) the smaller the value of the basic geometric parameter provides the higher the pressure developed by the GOS; 2) the passive flow pressure increasing at the intake of the HJP leads to a more significant expansion of the cavity-free operation area than a decreasing of the active flow pressure ahead of the nozzle. There were generalized data of experimental hydraulic jet pump characteristics studies, which were obtained in this range of baric conditions. As a result of the experimental data processing, nomograms of the hydraulic jet pump cavitation operating modes were obtained. Also an engineering methodology for calculating the hydraulic jet pump characteristics, which can be used both for selecting the HJP to the wells and for assessing the current operation was developed.
Based on the regression analysis, we obtained analytical dependencies of the cavitation parameters of the hydraulic jet pump (cavitation injection coefficient and cavitation dimensionless pressure drop) on the maximum dimensionless pressure drop corresponding to the zero injection coefficient. The error of the obtained model with respect to experimental characterization studies was estimated.
References
1. Sokolov E.Ya., Zinger N.M., Struynye apparaty (Jet devices), Moscow: Energoatomizdat Publ., 1989, 352 p.
2. Podvidz L.G., Kirillovskiy Yu.L., Raschet struynykh nasosov i ustanovok (Calculation of jet pumps and units), Proceedings of VIGM, 1968, V. 38, pp. 44–97.
3. Cunningham R.G., Jet pump theory and performance with fluids of high viscosity, Trans. ASME, 1957, V. 79, pp. 1807–1820.
4. Drozdov A.N., The technology and technique of oil production by submergible pumps in the complicated conditions, Moscow: MAKS press Publ., 2008, 312 p.
5. Patent no. 2238443 RF, Method for oil production and pump-ejector system for its realization, Inventors: Drozdov A.N., Monakhov V.V., Tsykin I.V.
6. Lyamaev B.F., Gidrostruynye nasosy i ustanovki (Hydrojet pumps and units), Leningrad, Mashinostroenie Publ., 1988, 256 p.
