乙二醇基纳米流体黏度的实验研究

Relative viscosity of ethylene glycol-based nanofluids

实验研究了3种乙二醇基纳米流体（Al2O3-EG、ZnO-EG、CuO-EG）在不同质量分数（0.5%/3.0%/5.0%/7.0%）下的相对黏度随温度的变化规律，实验所用乙二醇基纳米流体采用两步法配制获得。结果表明：在30～60℃温度范围内乙二醇基纳米流体的相对黏度同温度之间并无较强的函数关系（单调递增或递减）；但在质量分数较高时，3种乙二醇基纳米流体的相对黏度随温度的变化会出现波动，且以非球形颗粒的ZnO乙二醇基纳米流体的波动最为显著；乙二醇基纳米流体的相对黏度均随纳米颗粒体积分数的增大而增大，其中CuO乙二醇基纳米流体相对黏度的增长速度最快，Al2O3乙二醇基纳米流体的增长速度最慢。最后比较分析了文献中相对黏度预测公式与本文实验数据的相符程度。

An experimental study was carried out on the viscosity of ethylene glycol （EG） - based nanofluids containing Al2O3, ZnO and CuO nanoparticles with the particle concentrations of 0.5%/3.0%/5.0%/7.0%（mass）, respectively. Nanofluid samples were prepared by the two-step method without adding surfactant. The relative viscosity of EG-based nanofluids was not a strong monotonous function of temperature within 30-60℃. Nevertheless, the relative viscosity of EG-based nanofluids fluctuated with increasing temperature when mass fraction was high enough, with the fluctuation of ZnO （elongated）-EG nanofluid being more significant. It was also found that the relative viscosity of all the nanofluids tested increased with increasing volume fraction. Among them, CuO-EG increased most intensely while Al2O3-EG increased most moderately. Finally, a comparison analysis was made between the present experimental data and the prediction equations in literature.