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纳米流体作为一种新型换热介质, 其表面张力的变化与流体沸腾换热等热物理性质有着密切的联系.纳米流体通常由“两步法”制得, 其表面张力受温度、纳米颗粒粒径、纳米颗粒体积分数或质量分数等多方面影响.在前人的研究中, 表面张力随流体温度的升高而减小, 随纳米颗粒粒径的增加而增大, 但表面张力随纳米颗粒体积分数或质量分数的变化情况则不一致.通过总结由不同颗粒与不同基础流体组成的纳米流体表面张力的变化趋势, 分析纳米流体表面张力的变化与颗粒亲水性的关系.分析结果表明:亲水型颗粒与疏水型颗粒对纳米流体表面张力的影响恰好相反;亲水型纳米颗粒体积分数或质量分数不同时, 其纳米流体表面张力的变化也不相同.“,”As a new heat transfer medium, the surface tension of nanofluids has an important relationship with the thermophysical properties.Nanofluids mostly prepared with nanopaticles and base fluids by “two-step”method, sometimes with dispersant.The surface tension of nanofluids was influenced by temperature, particle size, particle concentration and so on.It was increased with increasing temperature and particles size, but the trend of surface tension was contradictory in the past research, compared the composition of nanofluids, the difference may caused by nanoparticles or dispersant.The effect of hydrophilic particles and hydrophobic particles on the surface tension of nanofluids was opposite, and for hydrophilic particles, the surface tension changes were not the same at different particle concentrations.