The actual task during operation of oil fields with sand manifestations is the protection of the downhole pumping equipment from mechanical impurities. Sand manifestations have a significant impact on the downhole pumping equipment reliability and they lead to failures in the electric submersible pump (ESP) unit due to abrasive wear of parts. Failures of ESP due to mechanical impurities in the produced fluid range from 35 to 50%. At present there are various technological methods for reducing sand production intensity and protecting downhole pumping equipment from mechanical impurities. One of the most common methods of protection against mechanical impurities in downhole pumping equipment is the use of mechanical filters installed both at the bottom of the well and in the composition of downhole pumping equipment. Among the various designs of mechanical filters wireframe filters have the best characteristics. We considered the numerical simulation of a two-phase fluid flow in a wireframe filter of an electric centrifugal pump. The two-phase fluid flow (a mixture of ‘water + sand’) is assumed to be laminar. The distribution of sand particle sizes is given by the Rosin – Rammler formula. Numerical hydrodynamic modeling is performed for two designs of the wireframe and wire filter of the electric centrifugal pump installation: 1) with a standard triangular cross-section of the wire; 2) with an improved cross-sectional profile of the wire in which the sides of the triangular profile are rounded. Three-dimensional geometric models are created in the computer aided design system Compass-3D. As a result of numerical simulation we obtained the two-phase fluid velocity distributions, the trajectory of the sand particles, the diameter of the sand particles distribution (passing through the filter,) and the transit time of the sand particles through the filter. It has been found that the maximum flow rates of a two-phase fluid in a wireframe filter with an improved cross-sectional profile of ESP unit are significantly higher than in a filter with a standard triangular cross-sectional profile of the wire. According to the calculation results we established that the wireframe filter with the improved cross-sectional profile of the wire has a higher value of the hydraulic parameter in comparison with the wireframe filter with the traditional triangular cross-section of the wire. Consequently the improved wireframe has less hydraulic resistance.
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