非牛顿高凝油的剪切特性

潍北油田高凝油含蜡量高、凝固点高，当温度低于析蜡点时，呈现出非牛顿流体特征，其特性受剪切作用影响较大。为此，开展了非牛顿高凝油的室内剪切降黏降凝实验。研究表明，在剪切作用下，非牛顿高凝油的黏度大幅降低；非牛顿高凝油具有剪切稀释性，且温度越低，剪切稀释性越明显；剪切速率对非牛顿高凝油的凝固温度、凝固时间影响较大，在凝固点附近剪切时，凝固温度可降低56 ℃、凝固时间明显延长；剪切时间对非牛顿高凝油的凝固温度影响很小，对凝固时间影响较大，在凝固点附近剪切20 min（转速100 r/min），凝固时间可延长817 min。

Shear Properties of Non-Newtonian High-pour-point-oil

The wax content and freezing point of the high-pour-point-oil in Weibei Oilfield are high. When the temperatureis below the wax precipitation point，the high-pour-point-oil behaves as a non-newtonian fluid which is greatly affected byshear. Thus，the shear viscosity and pour point reduction experiments of non-newtonian high-pour-point-oil were conducted.The results show that under the shear function，the viscosity of non-newtonian high-pour-point-oil is reduced greatly；the nonnewtonianhigh-pour-point-oil presents shear thinning and the lower the temperature is，the more obvious the shear thinningis；the shearing rate has greater effect on the freezing point and freezing time of non-newtonian high-pour-point-oil；under theshear function near freezing point，the freezing point can be reduced by 56 ℃ and the freezing time is obviously prolonged；the shearing time has little impact on the freezing point and has greater influence in freezing time and when it shears about20 min（the rotational speed is 100 r/min），the freezing time can be prolonged by 817 min.