采用"两步法"制备了含有不同质量分数的TiO2-水纳米流体,并观察了其稳定性。测量了不同质量分数的纳米流体在15~40℃时的粘度,结果表明,纳米流体的粘度随颗粒浓度的增加而增大,随温度的升高而以指数形式降低,并且各种纳米流体的粘度随温度的变化趋势相似。结合实验数据,对已有粘度计算公式进行修正,提出了涉及温度和颗粒浓度的纳米流体粘度计算公式。
TiO2-water nanofluids with different concentration were prepared by the two-step method,and the stability were researched.The viscosities of nanofluids with various mass fraction of TiO2 nanoparticles were measured at 15-40℃.The results showed that the viscosity of the nanofluids increased with increasing nanoparticles concentration and diminished exponentially with increasing temperature.Besides,the variation trends of viscosity with temperature for all concentrations of nanofluids were similar.A new equation for calculating the nanofluids viscosity by considering particle concentration and temperature was proposed based on the experimental data,which corrected the previous equations and could well predict the experimental results of TiO2-water nanofluids.