Measurement of the thermal conductivity of SiO2 nanofluids with an optimized transient hot wire method
Measurement of the thermal conductivity of SiO2 nanofluids with an optimized transient hot wire method
复制标题
采用优化的瞬态热线法测量 SiO2 纳米流体的热导率
DOI：
10.1016/j.tca.2018.01.008
复制
发表时间：
2018-03-10
影响因子：
3.5
通讯作者：
Dong, Cong
中科院分区：
文献类型：
--
作者：
Guo, Wenwen;Li, Guoneng;Dong, Cong
纳米流体的热导率增强会受到测量偏差和颗粒尺寸分布的影响。在目前的工作中，去离子水（DW）和乙二醇（EG）为基础的纳米流体的制备和表征。建立了基于瞬态热线法的纳米流体导热系数测量系统，并对两种基液的导热系数测量误差进行了全面分析。为减小加热功率不恒定和自然对流引起的测量误差，确定了合适的热线工作电流和测量时间。在此基础上，采用优化的测量参数对纳米流体的导热系数进行了测量。结果表明，当添加0.5vol. %的改性剂时，导热系数分别提高3.2%和9.6 SiO2-EG和1.0体积% SiO_2-EG，高于DW基纳米流体的结果（1.0%和3.4%）。这可能归因于较高的λ（布朗）值和颗粒形状分布的差异。
Thermal conductivity enhancement of nanofluids can be affected by measurement deviation and particle size distribution. In the present work, deionized water (DW) and ethylene glycol (EG) based nanofluids were made and characterized. A nanofluid thermal conductivity measurement system founded on transient hot wire method was built up and a comprehensive analysis regarding measurement error was made for the two base fluids. The proper hot wire working current and the measurement time were acquired to decrease the measurement error caused by non-constant heating power and natural convection. Then, the nanofluid thermal conductivity was measured with optimized measuring parameters. It was found that the thermal conductivity increases 3.2% and 9.6% for 0.5 vol.% SiO2-EG and 1.0 vol.% SiO2-EG, higher than the result for DW based nanofluids (1.0% and 3.4%). This may be attributed to the higher value of lambda(Brownian) and the difference in particle shape distribution.