摘要
采用Hotdisk热物性分析仪测量了Al2O3-H2O纳米流体的导热系数,探讨了pH值、分散剂加入量和纳米粒子含量对导热性能的影响.结果表明:最适宜的pH值和分散剂加入量能显著提高水溶液中Al2O3表面Zeta电位的绝对值,增大颗粒间的静电排斥力,悬浮液分散稳定性较好,导热系数较高;从分散稳定和导热系数提高两个方面来考虑,最佳pH值为8.0左右;在0.10%Al2O3-H2O纳米流体中,十二烷基苯磺酸钠的最佳加入量为0.10%.Al2O3-H2O纳米流体的导热系数随纳米粒子含量的增大而非线性增大,且大于现有理论(Hamilton-Crosser模型)预测值.
The thermal conductivity of Al2O3-H2O nano-fluid was measured using a Hotdisk thermophysical analyset, and the effects of pH value, dispersant concentration and nano-particle content （ mass fraction） on the thermal conductivity were investigated. The results show that, when the pH value and the dispersant dosage are both optimal, the absolute value of surface Zeta potential of Al2O3-H2O nano-fluid in aqueous solution significantly improves, thus increasing the electrostatic repulsive force among particles and resulting in better dispersion behavior and higher thermal conductivity of the nano-fluid. Moreover, it is found that pH 8.0 favors the dispersion behavior and the thermal conductivity, that the optimized content of sodium dodecylbenzenesulfonate is 0. 10% for 0. 10% Al2O3-H2O nano-fluid, and that the thermal conductivity of Al2O3-H2O nano-fluid, which is higher than that calculated based on the Hamilton-Crosser model, nonlinearly increases with the mass fraction of nano-particles.
出处
《华南理工大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2008年第11期7-11,共5页
Journal of South China University of Technology(Natural Science Edition)
基金
国家自然科学基金资助项目(20346001)
高等学校博士学科点专项科研基金资助项目(20050561017)
教育部新世纪优秀人才支持计划项目(NCET-04-0826)
中国博士后基金资助项目(20060400219)
作者简介
朱冬生（1964-），男，教授，博士生导师，主要从事强化传热、节能和制冷研究及应用．E-mail：cedshzhu@scut．edu．cn
