入口数量对旋流器分离天然气水合物浆体流场特性和分离性能的影响

Effects of Numbers of Inlets on Characteristics of Flow Field and Separation Performance of Natural Gas Hydrate Slurry in Hydrocyclone

用计算流体力学(CFD)方法对单入口、双入口和四入口旋流器进行数值模拟,分析这3种入口形式对旋流器的流场特性、湍动能、锥段切向速度以及分离性能的影响。计算结果表明,单入口旋流器的流场和湍动能具有不对称性,对旋流场产生强烈扰动,导致流场的稳定性降低,而双入口、四入口旋流器的流场具有良好的对称性和稳定性;双入口、四入口旋流器的锥段切向速度较大,有利于实现分离;在研究范围内,随着流速的增大,单入口旋流器砂分离效率先增大后减小,而双入口、四入口旋流器则持续增大,3种入口形式旋流器的水合物分离效率和压力降均随流速增大而增大;采用双入口形式更能保持流场稳定、提高分离性能、增大旋流器处理能力。研究工作对于旋流器在海洋天然气水合物开采的现场应用具有一定的指导意义。

The method of computational fluid dynamics(CFD)was applied to simulate hydrocyclones with single,double and four inlets.Effects of these three types of inlets on the flow field characteristics,turbulent kinetic energy,tangential velocity of conical segments and separation performances are analyzed.The results show that the flow field and turbulent kinetic energy in the single inlet hydrocyclones are asymmetrical,which makes strong disturbance to the flow field and reduces the stability of the flow field,and the flow fields in hydrocyclones with double and four inlets have higher symmetry and stability.Tangential velocity in double and four inlets hydrocyclones is larger than the single one,so as to enhance the separation behavior.In the research scope,efficiency of sand separation of the single inlet hydrocyclone increases firstly and then decrease with the increase of velocity of flow,but keeps increasing for double and four inlets hydrocyclones.In addition,natural gas hydrate separation and pressure drop of the three types of hydrocyclones keep increasing.At the same working condition,the double inlets hydrocyclone can keep the flow field stable and improve separation performance as well as increase the capacity of the hydrocyclone.The research work has certain guiding significance for the application of hydrocyclone in gas hydrate exploitation.