Structrue Design And Numerical Simulation Of The High Efficiency Gas-Liquid Mixer

Installation of the high efficiency air and liquid mixer before the Electrical Submersible Pump (ESP) is an effective way to help it work in the high-GOR well. However, the design theory of the system can be hardly built up as neither we know the mix mechanism of the mixer nor the theory of the influence of each factor on the mixer property and the experimental data are available. As a result, The dissertation mainly conducted research and numerical simulation using CFD method on a high efficiency air and liquid mixer which can satisfy the requirement of the high GOR well to explore its workings and the influence of each parameter on the performance of the mixer.Firstly, the present gas processing scheme and the gas treatment situation in Electrical Submersible Pump (ESP) system home and abroad were introduced. CFD numerical simulation of the mixer applied in the pump 98 has been done using the Euler model and the population balance model to explore the mechanisms of the high efficiency air and liquid mixer installed before the Electrical Submersible Pump (ESP),in which the bubble diameter, the flow pressure field and the distribution of the gas in the mixer were attained. The simulation results showed that the impeller outlet high pressure liquid will return to the lowest pressure zone in the blade non-working surface through round hole in the mixer cover, forming a cross-flow with the local flow in the impeller channel, thus resulting in intense shear friction in the zone, which can stop the large-scale bubble from gathering together. The mixer is composed of several parallel units, and when the high gas liquid ratio medium passed through the mixer, the bubble diameter in the unit was smaller than that in the former unit and the gas field will be more uniform gradually.In order to get the most suitable group of structure parameters of the high efficiency air and liquid mixers, several finite element model with different structure parameters, such as the diameter, numbers, section area and the position of the hole and the setting angle of blade outlet, have been simulated and analyzed. A high efficiency gas-liquid mixer which can be applied to the pump 130 has been designed based on the theory of similarity and the influence of the mixing performance of the mixer on the centrifugal pump has been analyzed, which suggested that the application of the high efficiency gas-liquid mixer before the centrifugal pump could improve the performance of the centrifugal pump.