| For the past few years, the rapid development of offshore oil and gas industry needs the gas-liquid separation technology to be compact, highly active and economic. But there are many kinds of faults in the existing gas-liquid separators, such as high pressure drop, wheels within wheels, failure-prone and so on. By numerical simulation and theoretical analysis, the paper presents a compact axial flow vane-guide cyclone separator with inner drum. And the flow field characteristics and separation performance of the separator is investigated, which lays the foundation for its industrialized popularization and application. The main contents and conclusions of research are following.Based on the basic principle of cyclone separation, the structure of a axial flow vane-guide cyclone separator is preliminary analyzed. The geometric model of the axial flow vane-guide cyclone separator is built. Using the CFD software, FLUENT, and the RNG k-& turbulence model, the paper obtains the impact of structural variety of the separator on the characteristic parameters of gas flow field. Using the dispersed phase model (DPM), the paper obtains the impact of the variety of separator structure and operating condition on the separation efficiency. So, it is presented that the separator includes several basic components: spiral inlet vanes, cone-shaped inner drum, case, liquid collector, expansion section and so on.It is discovered by investigating that the inner drum existing in the separation zone can prevent the swirl near the gas outlet diffuse inversely. So the strength and stability of the flow field is enhanced and the separation effect is improved. The incident angle of inlet vanes,β, plays a more important role than the number of inlet vanes, Nv, during the influence on flow field. The increase ofβleads to the increase of the rotation strength, pressure drop and separation efficiency. The decrease of Nv brings the slight fluctuations of the velocity and the separation efficiency is almost unaffected. The flow field is most stable while the coning of outer and inner drum is the same. Moreover, for the separation zone, the larger the length is and the bigger the coning is, the better the separation effect and the pressure recovery effect of the expansion section is. While the draining gap is larger than the exhaust, the pressure of the exhaust will decrease, which will lead to the decrease of separation efficiency. All these laws provide a reference for the selection of the separator structure.Based on the separation process and the stability requirement, the separator prototype is designed and manufactured. After that, the performance of the prototype is evaluated through experiments. It is shown that the pressure drop of the prototype will significantly reduce but the separation efficiency will not vary acutely with the increase of back pressure. For the same guide vane and liquid flow, the pressure drop and separation efficiency will both increase with the increase of gas flow. While the liquid flow and gas flow is stable, the pressure drop and separation efficiency will both increase with the increase ofβ. Furthermore, with the increase of gas flow, the increasedβbrings about larger and larger growing rate of pressure drop and gradually weakened impact on the separation efficiency. At the same gas flow rate, the separation efficiency will increase by degrees on the whole with the gradually increase of liquid volume and the increase of liquid flow leads to obvious decrease of the pressure drop when the GLR is comparatively large. The consistency of the experimental and numerical simulation results shows that the simulation method adopted in the paper is feasible.During the repeatable experiments, the performance of the separator prototype is stable. There is still significant room for its separation efficiency. Therefore, the application prospect of the axial flow vane-guide cyclone separator is fairly broad, which means great practical significance to the oil & gas production industry.
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