On the basis of the effective medium theory and the classical viscosity prediction model proposed by Pal et al, the apparent viscosity and rheological properties of the water in crude oil emulsion with natural surface active components such as asphaltene and resin are predicted. The adsorption and entrainment of continuous phase by the surfactants molecular, which leads to the increment of effective water fraction, is the inducement of Non-Newtonian behavior in the bulk emulsion. The two actions of promoting and counteracting effects on the effective water fraction are considered separately and represented by Water Fraction Factor and Particle Reynolds Number Factor respectively. The Water Fraction Factor takes into account the positive effect of water fraction and drop size distribution in microscope, while the Particle Reynolds Number Factor reflects the negative effect of shear rate at different drop size. A new prediction model taking the influence of nearly all factors such as drop size distribution, shear rate, water fraction into consideration was built. Measured viscosity of emulsion of the crude oil and water from an oilfield was used to verify the predicted results of the model, which proves that the new model is high in accuracy with a maximum relative error of 11.44%.%基于有效介质理论,在Pal等学者提出的经典黏度模型基础上,对含沥青质、胶质等界面活性成分的原油包水乳状液黏度及流变特性进行预测.界面活性分子对连续相的吸附与夹带,导致有效含水率的增加,是乳状液具有非牛顿性的诱因.将促进与阻碍乳状液有效含水率增加的正反2种作用分开考虑,并用含水率因子和颗粒雷诺数因子分别表征.含水率因子考虑了含水率及微观液滴分布对促进作用的影响;颗粒雷诺数因子着重体现不同液滴微观分布时剪切的破坏作用.建立了考虑微观液滴分布、剪切速率、含水率等多因素影响的黏度预测模型,油田现场原油、矿化水乳状液数据验证表明,所建模型具有较好的预测精度,预测结果的最大相对误差为11.44％.
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