为研究纳米流体稳定性并增强换热机理，在乙二醇/去离子水基液中，采用原液化学生长法制备了不同质量浓度（1%，2%，3%，4%和5%）的氧化硅-乙二醇/水纳米流体，通过Zeta电位测量和透射扫描电镜实验表征纳米流体的稳定性。实验测量并研究了温度和质量浓度对纳米流体的导热系数和粘度的影响。依据实测结果，利用格子玻尔兹曼方法对圆管内纳米流体的流动与换热特性进行数值模拟研究。结果表明：二氧化硅颗粒在基液中具有良好的稳定性；纳米流体的导热系数随温度和质量浓度的提高而增大；纳米流体的加入可以显著提高基液的对流换热系数，当质量浓度为5%时对流换热系数的提高幅度可达到25.5%。

To investigate nanofluid stability and enhance heat transfer mechanism，silicon oxideglycol/water nanofluids of different mass concentrations (1%，2%，3%，4% and 5%) were prepared in ethylene glycol/deionised water medium using the insitu chemical growth method，and its stability was characterised by Zeta potential measurements and transmission scanning electron microscopy images.The effects of temperature and mass concentration on the thermal conductivity coefficient and viscosity of the nanofluids were measured and investigated experimentally.Based on the measured results，the flow and heat transfer characteristics of the nanofluid inside the circular tube were investigated by numerical simulation using the lattice Boltzmann method.The results show that the silicon dioxide particles have good stability in the base fluid.The thermal conductivity coefficient of the nanofluid increases with increasing temperature and mass concentration.The addition of nanofluid can significantly improve the convective heat transfer coefficient of the base fluid.When the mass concentration is 5%，the convective heat transfer coefficient can be increased by 25.5%.

TK121

黑龙江省自然科学基金-中国杰出青年基金(YQ2021E008)