柱状螺旋导叶旋流分离器分离特性数值模拟

Numerical Simulation of Separation Properties in Cylindrical Helical Diffuser Cyclone Separator

针对深水生产油气海底混相输送的局限性,设计了柱状螺旋导叶旋流气液分离器,采用RNG k-ε湍流模型与mixture多相流模型对分离器流场及相分布进行了模拟分析,考察了螺距、螺旋圈数等结构参数对相分布及静压分布的影响。结果表明:螺旋通道可以保证油气混相在流动过程中形成明显的气液分离界面,溢流孔有助于分离的气相及时从集气管中排出;螺距的大小是控制旋流强度的关键参数,螺距越小,旋流场越强,相应的能耗也越大;螺旋圈数的增多有利于气液两相充分进行旋流分离;所设计分离器在较大的气液比范围内都具有较好的分离效果。

Cylindrical helical diffuser cyclone separator was designed to solve the limitation of subsea multiphase mixing transportation. Flow field and phase distribution properties were simulated by RNG k-ε turbulence model and mixture multiphase model; the effects of thread pitch and cycles on phase distribution and pressure distribution were studied. The results showed that oil and gas mixture flowing in the helix channels can form obvious gas and liquid interface; overflow holes contribute to exhaust the gas from helix channel to gas collecting tube timely. Thread pitch is the key parameter to control the rotational intensity; the smaller the thread pitch,the greater the swirl intensity. The energy consumption is also great accordingly. The increasing number of cycles can contribute to sufficient centrifugal separation of oil and gas. The seperator designed has preferable separation quality in wide range of gas and liquid ratio.