Research Of The Performance To The Self-supercharged Dynamic Hydrocyclone

Due to the deepening exploit of the oil field, some loose cement layer, and the production pressure, oil extraction liquid trends to have an increasingly sand content year by year. Currently, hydrocyclones are widely used in removing the grits from the oil extraction liquid, and show advantageous performance.To solve the problem of dispelling grit off the oil extraction liquid, we designed a self-supercharged dynamic hydrocyclone for dispelling grit. By adopting rational structure of the hydrocyclones and suitable control of putting in and out the raw material, it shows good separation efficiency and a certain capacity of pressurizing to ensure that the fluid in the cyclone separation unit does not produce pressure drop, while providing certain energy input to the downstream unit operation.This article uses the three-dimensional modeling software Pro/E to establish a three-dimensional geometric model of self-supercharged dynamic hydrocyclone for dispelling grit, uses pre-processing software Gambit of Fluent to differentiate three-dimensional model into meshes, and based on RNG k-εturbulence model, calculates a single phase flow field and two-phase flow field of hydrocyclone separately by using the fluid analysis software Fluent.In the calculation and research of single-phase flow field, by analyzing the three-dimensional distribution of the whole flow field, we make the comparison with the traditional static hydrocyclone flow field, and the results show that the single-phase flow field distribution of the self-supercharged dynamic hydrocyclone for dispelling grit is reasonable and consistent with the design concept. Turbocharged performance of the equipment mainly relies on the function of the overflow impeller, and therefore this article focuses on the circumstances that how overflow structure of the export acts on the pressure performance of the device. This paper analyzes the reasonable forms how the overflow outlet pipe are placed, and the results indicate that equipment shows best pressure performance when the square section tube is settled in the cutting direction; we propose two sets of pressure loss reduction programs in overflow export and demonstrate their feasibility, the results show that these two programs are not suitable for the device mentioned in the particular structure; we study the circumstance that how the external diameter of overflow impeller acts on the supercharger performance of the equipment, and the results show that increasing the impeller external diameter can significantly improve the pressure performance of the equipment. The operating parameters influencing the pressure performance of the equipment are calculated as well, and get the relationships between the pressure performance of the equipment and the changes of motor speed, split ratio and feed flow rate.In the calculation and research of two-phase flow field, we attain the path of particles moving in the device, which is consistent with the path in static hydrocyclone. The result shows that the design of cyclone in this article is reasonable and the separation of solid and liquid can be achieved in hydrocyclone. By calculating the separation efficiency of different sizes of particles in the device, we finally get that:separation diameter of the device d50 is about 43μm, and the separation limit d98 is about 80μm. In this paper, we use Rosin-Rammler distribution to describe the actual size distribution of sand particle, and the actual separation performance of particles in the device is calculated, where the separation efficiency is about 92.1%.The calculations mentioned above show that the flow field distribution of the self-supercharged dynamic hydrocyclone for dispelling grit designed in this paper is rational. It has outstanding separation and supercharged performance and can meet the requirements of industrial production.