摘要
采用两步法制备体积分数为0.1%0.5%的S iO2-水纳米流体,并利用zeta电位、吸光度和粒度分析表征其悬浮稳定性,研究发现超声振动5 h其悬浮稳定性最佳。采用瞬态热线法测量纳米流体的导热系数,结果表明：纳米流体导热系数的变化与纳米颗粒体积分数和温度的变化成正比,其中25℃时体积分数为0.3%的S iO2-水纳米流体相对于水的导热系数提高11.5%,而在50℃时则提高46.5%。建立纳米流体导热系数模型,与其他模型比较发现,本理论模型更接近于实验值。
Various SiO2-water nanofluids with volume fractions from 0.1% to 0.5% are prepared using the two-step method.The analysis of zeta potential,absorbency and particle size indicates that ultrasonic vibration for 5 h can uniformly disperse Al2O3 nanoparticles in water.Thermal conductivity is measured by the transient hot-wire method,which shows that the thermal conductivity increases with the increase of nanofluid particle volume fraction and temperature.The thermal conductivity of 0.3vol% SiO2-water nanofluid increases by 11.5% at 25 ℃,while it increases by 46.5% at 50 ℃ when compared with water at the same temperatures.A thermal conductivity model of nanofluid is established,which is closer to experimental values than other models.
出处
《济南大学学报（自然科学版）》
CAS
北大核心
2010年第3期247-250,共4页
Journal of University of Jinan(Science and Technology)
基金
山东省自然科学基金(Y2007F28)
山东大学高校院所自主创新计划(200906048)
关键词
纳米流体
制备
稳定性
导热系数
nanofluid
preparation
stability
thermal conductivity
