| At present, the main problems existing in civil gas/liquid separation system are: useful energy is completely or partly consumed in multiphase flow and, secondly, separation is not thorough when froth and emulsification produce. The main deficiencies in natural gas processing are the separation of treating process and gas/fluid separating, the complexity of process, too many equipments and low economic efficiency. In order to solve the above problems, civil scholars working in oil industry has been doing unremitting research in isolation technique and made certain progress, but still could not solve the problem completely. One kind of midget highly efficient revolving turbine separator, which gathers gas/liquid separation and natural gas processing and shaft merit output in one body, is developed by American MPPT Corporation to solve the problems completely. The separator has some advantages, such as compact structure, high separating efficiency, strong compatibility and full use of available energy, etc.. At abroad, the separator is being tested in the offshore platform and land oil-gas field at present and good progress is made. However, the internal structure of separator and relative fundamental research is secret. Therefore, it is necessary to conduct the detailed research on it. The paper conducts a thorough systematic research on revolving turbine separator in forms of theoretical analysis, structural design, numerical simulation and experiment. The research of the separator has very important theory and application value in gas/liquid separation and natural gas process, and for that civil oil industry possesses the proprietary intellectual property rights of revolving turbine separator as well. The main contents and conclusions of the research are as follows:Based on the basic principle of the rotary turbine separator, the overall structure of a rotary turbine separator is preliminary analyzed. It includes several basic components: two-phase nozzle, separating rotor, gas & liquid exports, axle, sealed and lubricated part.Based on the two-phase nozzle theoretical models, i.e. uniform theoretical model and Rudinger isothermal model, variable velocity ratio isothermal model and the droplet Two-phase fluid coupling model used for two-phase nozzle design and parametric analysis are studied in this paper, in which the coupling effect between gas and liquid in the nozzle as well as controlling flow parameters are fully considered. The possible condition that fluids in the nozzle are in the same temperature is theoretically analysed. The condition for the droplet Two-phase fluid coupling model can be simplified as variable velocity ratio isothermal model is presented. The two-phase nozzle models are comparisiond and the droplet Two- phase fluid coupling model is proved to be reasonable. A program for two-phase nozzle design and parametric analysis is compiled and preliminary parametric calculation is done .By changing the value of some droplet characters in the two-phase nozzle model, the sensitivity of nozzle performance on the characters of droplet is studied. The effect of two-phase nozzle's parameters to its performance is analyzed through droplet Two- phase fluid coupling model. And the energy distribution between gas and liquid is estimated. According to the parameter analysis, the standard for optimal nozzle design and performance is determined. A method for rapid design of approximate nozzle geometric parameter is developed on the basis of Rudinger isothermal theory.The performance of two-phase nozzle off-design is analyzed. And two models calculating the performances of two-phase nozzle under off-design work conditions are presented and comparisiond, i.e. the heat transfer off-design work conditions model and the isothermal off-design work conditions model. For two-phase nozzle given the geometric parameters, the relationships of load ratio, inlet pressure and temperature, mass flow of gas fluid and efficiency of the nozzle are studied in the paper. The relative contents also include the influence of heat transfer to nozzle performance and the factors influencing two-phase Mach number and velocity of sound.Based on Rudinger isothermal model, variable velocity ratio isothermal model and the droplet Two-phase fluid coupling model, four two-phase nozzles are designed. And numerical simulation is done using Fluent. The simulation results and theoretical results under off-design work conditions are comparisiond and proved the correctness of the theory. The numerical simulation results of four nozzles are comparisiond and the two-phase nozzle fit for rotating turbine separator is selected. Two-phase nozzle theory is further verified through experiments.According to the research of two-phase nozzle, the detailed structure of rotary turbine separator is designed. The rotary turbine separator includes: the surface of separation, separation wheel, gas & liquid discharging devices etc., the gas-liquid reaction nozzle which can increase the output shaft power, the gas reacting impeller, etc.. The rotational speed of separator and the motion of droplet on the separation surface are systematically analyzed. And qualitative analysis of part of them is done by simple numerical simulation. The simulation results can guide the optimal design of the separator structure. The sealing system, shaft and bearing system of the separator are designed and verified. The design of rotating turbine separator is completed and experimental prototype is manufactured.A simple laboratory experiment of separator prototype is done. The main factors influencing rotaryspeed of separator, output of shaft power and separation efficiency are analysed in this paper, and thestructure of the separator is assessed.Numerical simulation of the phase change of two-phase flow in the designed nozzle is finished using Fluent, and the application of the separator in the area of gas dehydration is initially studied.
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