In this study, the viscosity of the fullerene/hydraulic oil nanofluid has been investigated experimentally. The purpose of this research is improving the properties of hydraulic oil by adding fullerene nanoparticles at the volume fractions of 0.05% to 2% in the base fluid. Hence, the nanofluid has been prepared by a two-step method using an ultrasonic homogenizer. The results showed that nanofluid behavior is non-Newtonian in all volume fractions. Moreover, in accordance with other common fluids, the viscosity of the nanofluid declined with rising temperature. The changes of viscosity included two trends. The maximum value of the viscosity at each temperature occurred at concentration of 0.4%, and it decreased at higher concentrations. Furthermore, comparing experimental results with the presented models revealed that previous analytical models are not able to predict the viscosity of the fullerene/hydraulic oil nanofluid. Hence, the response surface methodology has been applied to predict the dynamic viscosity of the hydraulic oil containing fullerene nanoparticle.

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富勒烯/液压油纳米流体的流变行为的实验研究

在这项研究中，已经对富勒烯/液压油纳米流体的粘度进行了实验研究。这项研究的目的是通过在基础流体中以0.05％至2％的体积分数添加富勒烯纳米颗粒来改善液压油的性能。因此，已经使用超声波均化器通过两步法制备了纳米流体。结果表明，在所有体积分数中，纳米流体行为都是非牛顿性的。此外，根据其他常见流体，纳米流体的粘度随温度升高而下降。粘度的变化包括两个趋势。在每个温度下，粘度的最大值出现在浓度为0.4％的位置，而在较高的浓度下则减小。此外，将实验结果与所提供的模型进行比较，发现先前的分析模型无法预测富勒烯/液压油纳米流体的粘度。因此，已经将响应表面方法应用于预测含富勒烯纳米颗粒的液压油的动态粘度。