考虑剪切速率及温度影响的气油两相流本构方程

Constitutive Equation of Bubbly Oil Considering Shear Rate and Temperature

针对目前关于气油两相流本构方程的研究仅限于极低剪切速率范围,且均没有考虑温度影响的现状,构建气油两相流的制备装置,提出基于图像分析的气油两相流含气率的测定方法,通过Physica MCR 101旋转式流变仪测试不同温度及含气率下较宽剪切速率范围内气油两相流的流变特性,考察剪切速率、温度及含气率对气油两相流流变特性的影响规律,给出适用于不同剪切速率及温度范围的CD15W/40润滑油气油两相流的黏度模型及本构方程。结果表明,在同一剪切速率下,气油两相流的剪切变稀性质随着温度的升高而减弱,随着含气率的增加而增强。气油两相流含气率对其黏度的影响与剪切速率有关,随着含气率的增加,气油两相流的黏度在较低剪切速率下增加,但在较高剪切速率下减小。

So far, the studies of the constitutive equation of bubbly oil have been limited to extremely low shear rate range, and the influence of the temperature has not been considered as well. The bubbly oil preparation device is set up, and the analytical technique based on image processing to characterize bubble content is proposed. The rheological performance of bubbly oil is then tested with Physica MCR 101 rotating theological instrument within a wider range of shear rate under different temperature and bubble content. The influences of shear rate, temperature and bubble content on the rhe01ogical performance of bubbly oil are studied. A novel viscosity model and constitutive equation of CD15W/40 are developed, which can be applied to the situations with various shear rates and temperatures. The results show that at the same shear rate, the features of shear thinning of the bubbly oil are weakened as the temperature rises, while they are strengthened with the bubble content increasing. The influence of bubble content on the viscosity of bubbly oil is dependent on the shear rate. As the bubble content increases, the viscosity increases under lower shear rate, while the viscosity decreases under higher shear rate.