【摘要】 石墨烯在结构及性能上的独特优势赋予了其在现代科学和技术领域不可替代的作用。石墨烯的许多物理化学性质对石墨烯的层数和结构尺寸十分敏感。本研究选取了三种典型的石墨烯纳米颗粒,分别是极少层石墨烯(1#)、少层石墨烯(2#)和多层石墨烯(3#),将它们分别添加在现有的润滑油中,制备了不同质量分数的纳米流体,并对其导热系数、比热容和粘度进行实验测量。结果表明,采用两步法制备的石墨烯纳米流体具有很好的稳定性,通过高速离心机测试发现,其分散性较好,无团聚现象。在温度相同、石墨烯颗粒质量分数也相同的情况下,1#石墨烯所制备的纳米流体具有最优的热物性能,其导热系数较基液最大可以提高143.63%,比热容较基液可以提高23.58%。2#石墨烯所制备的纳米流体热物性能次之,3#石墨烯最差。更多还原

【Abstract】 The unique advantages of graphene in structure and performance give it an irreplaceable role in modern science and technology. Many phy-sical and chemical properties of graphene are very sensitive to the number of layers and structure size of graphene. In this study, three kinds of typical graphene nanoparticles were selected, which were very few layers graphene(1#), few layers graphene(2#) and multilayer graphene(3#), the nanofluids with different mass fraction were prepared by adding them to the existing lubricating oil. The thermal conductivity, specific heat capacity and viscosity were measured. The results show that the graphene nanofluid prepared by the two-step method had good stability, and it had good dispersion and no agglomeration by high-speed centrifuge test. At the same temperature and the same mass fraction of graphene particles, the nanofluids prepared by 1# graphene had the best thermophysical properties. Compared with the base liquid, the thermal conductivity can increase by 143.63%, and the specific heat capacity can increase by 23.58%. The thermal properties of nanofluids by 2# graphene were the second, while the thermal properties of nanofluids by 3# graphene were the worst.更多还原