Design and Validation of a Numerical Model for Inclined Oil-Water Flow

建议的研究旨在开发和验证一个时间相关的，倾斜的油水管流的三维数值模型。倾斜的油-水流通常在威尔斯油井的井下遇到，在该油井的深度处，流体静压太高而不允许溶解的气体从溶液中出来。石油公司使用“生产测井工具”（PLT）在这些威尔斯中进行流体流量测量，作为最大化英国储层石油产量过程的一部分，数值模型将极大地促进对这些PLT测量数据的解释。倾斜油水两相流由于存在间歇性形成和衰减的Kelvin-Helmholtz（K-H）波而变得非常复杂。这些波的作用是在油和水两者的局部速度矢量的幅度和方向上引起大的时间依赖性变化，以及在两相的局部体积分数分布中引起大的时间依赖性变化。它的目的是，数值模型将预测倾斜的油-水流的结构的细节，包括（i）在两个阶段的局部速度矢量分布的时间依赖性变化;（ii）在两个阶段的局部体积分数分布的时间依赖性变化;和（iii）的结构和流动中的间歇K-H波的传播速度。如果该模型在预测宽范围的流动条件下的K-H波的传播速度方面是成功的，则这将极大地促进对新的生产测井技术的解释，该生产测井技术根据K-H波速度的测量来估计油-水混合物的表面速度。将使用实验室流动回路和两种独立的、最先进的测量技术在水包油流动中验证数值模型，所述测量技术使得能够测量分散相（油）的局部速度矢量和待测量的两相的局部体积分数的时间依赖性测量。这些技术是：（i）高速双平面电阻抗断层扫描（EIT）和（ii）本地，多传感器电导探头。两种技术都可以在平均分散相体积分数的高值下操作（例如，对于水包油流，EIT操作高达约45%的油体积分数，并且局部探针操作高达约30%的油体积分数），其中由于来自多个油滴表面的光散射的影响和油-水混合物的不透明性，通常不能使用诸如PIV和LDA的光学技术。鉴于高速，双平面EIT和本地多传感器电导探头的高度新颖和创新的性质，将开展工作，以开发这些技术，使从它们获得的测量是足够的精度，是有用的，在验证的数值模型。由于这两种测量技术都是新颖的，因此拟议研究的一个重要特点是相互交叉检查这些技术。

The proposed research seeks to develop and validate a time dependent, 3D numerical model of inclined oil-water pipe flow. Inclined oil-water flows are commonly encountered downhole in oil wells at depths where the hydrostatic pressure is too high to allow dissolved gases to come out of solution. 'Production Logging Tools' (PLTs) are used by oil companies to make fluid flow measurements in such oil wells, as part of the process of maximising oil production from UK reservoirs, and the numerical model will greatly facilitate interpretation of measurement data from these PLTs. Inclined oil-water flows are highly complex due to the presence of Kelvin-Helmholtz (K-H) waves which intermittently form and decay. The effect of these waves is to induce large, time dependent variations in the magnitude and direction of the local velocity vector of both the oil and water as well as causing large time dependent variations in the local volume fraction distribution of both phases. It is intended that the numerical model will predict the fine detail of the structure of inclined oil-water flows including (i) time dependent variations in the local velocity vector distribution of both phases; (ii) time dependent variations in the local volume fraction distribution of both phases; and (iii) the structure and propagation speed of intermittent K-H waves in the flow. If the model is successful in predicting the propagation speed of K-H waves for a wide range of flow conditions this will greatly facilitate interpretation of a novel Production Logging technique which estimates the oil-water mixture superficial velocity from measurements of the K-H wave speed. The numerical model will be validated in oil-in-water flows using a laboratory flow loop and two independent, state of the art measurement techniques which enable time dependent measurements of the local velocity vector of the dispersed phase (oil) and the local volume fraction of both phases to be measured. These techniques are; (i) high speed dual-plane Electrical Impedance Tomography (EIT) and (ii) the local, multi-sensor conductance probe. Both techniques can operate at high values of the mean dispersed phase volume fraction (e.g. for oil-in-water flows EIT operates up to about 45% oil volume fraction and the local probe operates up to about 30% oil volume fraction) where optical techniques such as PIV and LDA cannot generally be used due to the effects of light scattering from multiple oil droplet surfaces and the opacity of the oil-water mixture. Given the highly novel and innovative nature of both high speed, dual-plane EIT and the local multi-sensor conductance probe, work will be undertaken to develop these techniques such that measurements obtained from them are of sufficient accuracy to be useful in validating the numerical model. Since both measurement techniques are novel, an important feature of the proposed research will be the cross-checking of these techniques against each other.