| Spiral gas-liquid separator is a highly efficient and compact gas-liquid separator with simple structure, and used widely in oil-gas separation in natural gas and oil exploitation industry, air cleaning in compressed air industry and helium separation in aerospace industry. However, the two-phase flow field in spiral separator is loo complex to be characterized using analytical approach. As a result, the effect of spiral structural parameters on separator performance was not well understood. Moreover, it was very difficult to deduce the quantitative formulas for pressure drop and separating efficiency.Based on the above issues, the gas-liquid-two-phase flow in the spiral gas-liquid separator has been studied in terms of the CFD (computational fluid dynamics) simulation and experimental research. Major research work and conclusions are summarized as follows:(1) The state-of-the-art of spiral gas-liquid separator, gas-liquid-two-phase flow simulation, droplet collision and reunite and numerical simulation is reviewed. Research needs and provisions are proposed.(2) The gas turbulent flow field is simulated with CFD soflware FLUENT. The effect of helix configuration parameters upon pressure drop, such as helical number, helical pitch and so on is analyzed. By comparing pressure field contour pictures in different spiral models, the necessary information needed to design high efficiency spiral separator is achieved.(3) On the basis of two-phase flow theory, stochastic tracking model is used for random droplets in the gas-liquid turbulent flow simulation by CFD software FLUENT. The effect of structural parameters of spiral separators on gas-liquid two-phase flow is studied. Furthermore, flow field distribution and separation efficiency are calculated and the track of droplets is demonstrated. The numerical results show that the CFD method is a powerful tool for the design of the spiral separators.(4) A set of experimental system used to measure flow field of spiral separator is constructed, with the experimental data, such as the pressure and flow rate of gas and the weight of drained water etc., being acquired by a computer. A comparison between the experimental measurement and the numerical results reveals that they have same development trends though there exists a little deviation.(5) The calculation formula for pressure drop is deduced analytically. Its coefficients can be obtained from the regression analysis of related numerical simulation data.(6) Finally, a simplified design method for the spiral gas-liquid separator is presentedbased on structural feature and flow behavior of the spirals, which lays a solid foundation for the optimum design of the spiral gas-liquid separators.
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