纳米冷冻机油热导率的实验研究.pdf

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2015年第34卷第2期
CHEMICAL INDUSTRY AND ENGINEERING PROGRES
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研究开发
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纳米冷冻机油热导率的实验研究
娄江峰,张华,王瑞祥2
(1上海理工大学能源与动力工程学院,上海2000332北京建筑大学环境与能源工程学院,北京10003)
摘要:采用两步法,以聚乙烯呲咯烷酮(PVP)为表面活性剂,制备了不同种类的纳米冷冻机油并对其分散稳定
性进行了实验研究。采用 Hot Disk热常数分析仪,测量了40℃下纳米冷冻机油(纳米材料为TiO2、Al2O3、Fe2O3
石墨和碳纳米管,体积分数为0.05%、0.1%、0.2%、0.5%、1%和2%)的热导率,分析研究了颗粒体积分数
粒径、材质以及表面活性剂等因素的影响。结果表明:納米冷冻机油的热导率随着颗粒体积分数的提高而增大;
相同体积分数下随着颗粒粒径的増大而减小,而相同粒径下又随着颗粒材质热导率的提高而增大;同时分散稳
定性优的纳米冷冻机油热导率较高。基于纳米粒子的体积分数、粒径、团聚理论和布朗运动开发了納米冷冻机
油热导率预测模型,并与实验数据进行比较,发现预测值与90%的实验数掲偏差在士3%以内,平均偏差1.6%
关键词:納米粒子;表面活性剂;分散;热导率;粒径;预测模型
中图分类号:TB612;TB383
文献标志码:A
文章编号:1000-6613(2015)02-0495-05
DOI:10.16085/j.iss,1000-6613.2015.02.030
Experimental study on the thermal conductivity of nano-refrigeration-oill
LOU Jiangfeng ZHANG Hua, WANG Ruixiang
( School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai 20093, China
School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture
Beijing 100044, China>
Abstract: Naphthenic nano-refrigeration-oils (NROS) with different types of nanoparticles were
prepared by two-step method with polyvinyl pyrrolidone ( VP)as surfactant. The dispersion stability
and the thermal conductivity of the NROS were investigated experimentally by Shimadzu Uv-vis
Hot Disk thermal constant analyzer, respectively. The NROS with various nanparticles (including
Tio2. Al203, Fe203 graphite and NT)with volume fractions of 0.05% 0.1%, 0.2%,0.5%, 1%
and 2% were tested at C. And the influence of volume fraction, particle size, material and surfactant
was analyzed. The results show that the thermal conductivity of NROS increases with the increase of
nanoparticle volume fractions. The thermal conductivity of NROS shows a downward trend when the
particle size increases at the same volume fraction. While at same particle size it improves with the
thermal conductivity of particle material. Besides, the NROS with better dispersion stability have
higher thermal conductivity. A model for predicting the thermal conductivity of NROS was developed
based on volume fraction, particles, aggregation theory and Brownian movement of nanoparticles. The
predictions of the model agree with 90% of experimental data within the deviation of+3%, and the
mean deviation of 1.6%
Key words: nanoparticles; surfactants; dispersion; thermal conductivity; particle size; prediction model
收稿日期:2014-09-09;修改稿日期:2014-10-08
第一作者:娄江峰(1985-),男,博士研究生,主要从事纳米制冷
基金项目:国家自然科学基金(51176124)、上海市曙光计划(跟踪)技术的研究。联系人:张华,教授,博士生导师,主要从事制冷空调
(10GG21)及上海市研究生创新基金( WWCXSL1101)项目。
与新能源利用方向的研究。E-mailzhanghua3000163.com