输油管线内气液固三相流中沙粒沉积规律的数值模拟研究

Numerical Simulation of Sand Deposition in Gas-Liquid-Solid Flow within Oilfield Pipeline

以苏丹油田Palouge油区的输油管线参数为研究对象,基于多相流混合模型,采用Fluent软件对输油管线内的气液固三相流中的沙粒沉积过程进行了数值模拟,研究了流速、含沙量、含水量、压力和原油粘度对沙粒沉积规律的影响。结果表明:沙粒在输油管线中的沉积分为起始沉积段、过渡段和稳定段。平均沉沙量随流速、含水量的增大而减小,随含沙量的增大而增加,压力为0.2MPa和原油粘度为0.1 Pa.s时,分别达到51.80%和45.76%极小值。沉沙量最大位置随流速、含水量而右移,随含沙量增大而左移,随着压力和原油粘度增大存在一临界值(0.2MPa时4.28m和0.1Pa.s时3.68m)。过渡段宽度随流速和压力增大存在一临界值,随含沙量、含水量和原油粘度的增大存在极值(8%时22.56m,20%时21.80m和0.1Pa.s时22.19m)。过渡段压差直接影响了过渡段的宽度。流速和含沙量对其沉积规律的影响最大。

Taking oilfield pipeline＇ s parameters as the object of study and basing on the mixed model for multi-phase flow, the Fluent was used to simulate deposition process of gas-liquid-solid flow within oilfield pipeline, including the study on the effect of flow velocity, sand concentration, moisture content, pressure and viscosity of crude oil on sand deposition. The results show that the sand deposition can be divided into incep- tion deposition stage, transition stage and stable stage, and the average volume of sand deposition decreases with the increased flow velocity and moisture content and become increased with the sand concentration. The minimum value of 51.80% and 45.76% can be reached when the pressure and viscosity stays at 0.2MPa and 0.1Pa·s, respectively. The location of maximum sand deposition shifts right with the flow velocity and mois-ture content and does left with the sand concentration, and it has a critical value with the increase of the crude oil＇s pressure and viscosity （0.2 M Pa of 4.28m and 0.1 Pa·s of 3.68m, respectively）. The width of deposition transition stage has a critical value with the increase of flow velocity and pressure and has an extreme value with the increase of sand concentration, moisture content and viscosity of crude oil （8% of 22.56m, 0.2MPa of 21.80m and 0.1Pa·s of 22.19m, respectively）. The differential pressure of transition stage affects the width of transition stage directly. Both flow velocity and sand concentration affect the sand deposition greatly.