In this study, the cooling performance of nanofluids in car radiators was investigated. A car radiator, temperature measuring instrument, and other components were used to set up the experimental device, and the temperature of nanofluids passing through the radiator was measured by this device. Three kinds of nanoparticles, γ-Al2O3, α-Al2O3, and ZnO, were added to propylene glycol to prepared nanofluids, and the effects of nanoparticle size and type, volume concentration, initial temperature, and flow rate were tested. The results indicated that the heat transfer coefficients of all nanofluids first increased and then decreased with an increase in volume concentration. The ZnO-propylene glycol nanofluid reached a maximum heat transfer coefficient at 0.3 vol%, and the coefficient decreased by 25.6% with an increase in volume concentration from 0.3 vol% to 0.5 vol%. Smaller particles provided a better cooling performance, and the 0.1 vol% γ-Al2O3-propylene glycol nanofluid had a 19.9% increase in heat transfer coefficient compared with that of α-Al2O3-propylene glycol. An increase in flow rate resulted in a 10.5% increase in the heat transfer coefficient of the 0.5 vol% α-Al2O3-propylene glycol nanofluid. In addition, the experimental temperature range of 40–60°C improved the heat transfer coefficient of the 0.2 vol% ZnO-propylene glycol nanofluid by 46.4%.

中文翻译：

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ZnO-PG、α-Al2O3-PG和γ-Al2O3-PG纳米流体在汽车散热器中的传热性能比较

在这项研究中，研究了纳米流体在汽车散热器中的冷却性能。采用汽车散热器、测温仪等部件搭建实验装置，通过该装置测量纳米流体通过散热器的温度。将γ-Al2O3、α-Al2O3和ZnO三种纳米粒子加入丙二醇制备纳米流体，并测试纳米粒子的大小和类型、体积浓度、初始温度和流速的影响。结果表明，随着体积浓度的增加，所有纳米流体的传热系数先增大后减小。ZnO-丙二醇纳米流体在0.3 vol%时达到最大传热系数，随着体积浓度从0增加，传热系数降低25.6%。3 体积％至 0.5 体积％。较小的颗粒提供了更好的冷却性能，与 α-Al2O3-丙二醇相比，0.1 vol% 的 γ-Al2O3-丙二醇纳米流体的传热系数增加了 19.9%。流速的增加导致 0.5 vol% α-Al2O3-丙二醇纳米流体的传热系数增加 10.5%。此外，40-60°C 的实验温度范围将 0.2 vol% ZnO-丙二醇纳米流体的传热系数提高了 46.4%。5 vol% α-Al2O3-丙二醇纳米流体。此外，40-60°C 的实验温度范围将 0.2 vol% ZnO-丙二醇纳米流体的传热系数提高了 46.4%。5 vol% α-Al2O3-丙二醇纳米流体。此外，40-60°C 的实验温度范围将 0.2 vol% ZnO-丙二醇纳米流体的传热系数提高了 46.4%。