中文摘要：

基于纳米粒子表面吸附层的分析,构建包含纳米粒子、分散剂层、类固相层和分散基液的导热单元,利用最小热阻法建立纳米流体的有效导热系数模型,推导出其表达式,并分别讨论纳米粒子粒径、分散剂层和类固相层对纳米流体的有效导热系数的影响。结果表明,考虑类固相层的影响得到的纳米流体的有效导热系数比不考虑其影响得到的数值大;添加分散剂后,纳米流体的有效导热系数随着分散剂导热系数的增大而增大,当纳米粒子较小时分散剂在纳米粒子表面的吸附层对纳米流体导热系数的影响更大。

英文摘要：

Based on the analysis of the absorbed layer on the surface of nanoparticles,a heat transfer unit was developed involving the nanoparticle,surfactant layer,quasi-solid layer and the base fluid.An effective thermal conductivity model of nanofluids was developed by the least thermal resistance method and the formula was deduced.The effects of the nanoparticle size,the surfactant layer and quasi-solid layer on the effective thermal conductivity of nanofluids were discussed.The results indicate that,the effective thermal conductivity of nanofluid would increase if the quasi-solid layer is considered; it increases with the thermal conductivity of the surfactant; the surfactant layers that absorbed on the surface of the nanoparticles have more obvious effect on the effective thermal conductivity of nanofluid when the nanoparticles are smaller.