STUDY OF THE INFLUENCE OF FLUID FLOW SWIRLS ON THE HYDRAULIC RESISTANCE OF A PIPELINE

Abstract

Background With the increase in the volume of pumping oil and oil products, as well as the significant importance of measures to ensure energy-efficient operation of main pumping units (MPU), according to the Federal Law dd. November 23, 2009 No. 261-ФЗ «On energy conservation and on improving energy efficiency and on amendments to separate legislative acts of the Russian Federation», the development of recommendations for reducing energy costs in oil transportation is an important technological task. Operating experience of oil main pipelines (MP) indicates that the use of dragreducing additives (DRA) is one of the most effective ways to reduce the energy consumption of MPU (increase the throughput of MP). The determination of the effectiveness of DRA is carried out in the process of pilot industrial tests for oil pressure vessels, which require material resources and time, and conducting research in laboratory conditions is complicated by the presence of an unreliable transfer of the results of laboratory experiments to real oil pumping conditions. An analysis of the world experience in the application of DRA in oil pipelines was made, which showed that the effectiveness of using DRA to reduce hydraulic friction losses in the pipeline depends on many factors, such as the properties of the pumped oil, the solubility of the additive, and the rate of dosing of the additive into the transported medium, flow regime (Reynolds number), multiphase flow. One of the solutions to the above problem is to reduce hydraulic friction losses in the oil pipeline, based on the use of vortex fluid flow, since overcoming hydraulic resistance in the pipeline accounts for 33.9 % of electric energy costs. Aims and Objectives The aim of the work was to assess the effect of fluid flow swirls on the hydraulic resistance of the pipeline. The following tasks were solved: to conduct computer modeling in the SolidWorks Flow Simulation software package (hereinafter referred to as the PC) to obtain the dependence of the flow rate and pressure drop along the pipeline length on the experimental bench model; determine the most effective design parameters of the pipe with a spiral channel (spiral twist step) for the prototype experimental bench (DN 15); calculate the coefficient of hydraulic resistance of the pipeline when pumping fluid with swirling and without swirling flow. Methods The article presents the results of computer simulation obtained by the finite volume method in the SolidWorks Flow Simulation software package, the dependences of the flow rate and pressure drop along the length of the pipeline for various diameters during the vortex flow of an incompressible fluid through the pipeline. Results Recommendations have been developed on the design of the spiral channel in the pipe to increase the efficiency of the use of the vortex flow in order to reduce hydraulic resistance when pumping an incompressible fluid. The results obtained allow us to conclude that it is advisable to conduct further experimental studies in this direction in order to develop a method to increase the throughput of the pipeline.