摘要
导热系数是衡量纳米流体强化换热的最重要的参数,但在不同学者的研究中,对于同一种纳米流体所测得的导热系数却有很大差别。本文针对影响纳米流体导热系数实验测量的因素进行研究,在相同的实验条件下,分别运用Hotdisk导热仪和闪光法导热仪对水基二氧化钛纳米流体的导热系数进行了测量。实验结果表明,用Hotdisk法的测量结果比用闪光法测得的高21%～34%。通过计算分析发现:自然对流是引起纳米流体导热系数测量结果多变的重要原因之一。
Thermal conductivity is the most important parameter to estimate the enhancement of heat transfer of nanofluids.But the thermal conductivities reported by different researchers are usually quite different.Therefore,the factors that influence the measurement of the thermal conductivity of nanofluids were investigated in the present work.The thermal conductivities of aqueous TiO2 nanofluids were measured by both the hot disk method and the laser flash method,respectively,under otherwise the same experimental conditions.The results obtined in the hot disk method were 21%~34% higher than those by the laser flash method.It was found by calculation that free convection in the nanofluid is one of the main reasons for the diversity of experimental results of thermal conductivity.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2013年第4期592-597,共6页
Journal of Materials Science and Engineering
基金
国家自然科学基金-广东联合资助项目(U0934006)
国家自然科学基金资助项目(51106031)
广东省教育部产学研结合资助项目(2011B090400374)
关键词
纳米流体
导热系数
实验测试法
自然对流
分散剂
nanofluid
thermal conductivity
experimental technique
free convection
dispersant
