纳米颗粒TiO2／HFC134a工质对流换热实验研究  

CONVECTIVE HEAT TRANSFER OF NANOPARTICLES TIO_2 AND HFC134A MIXTURES

作　　者：毕胜山[1] 史琳[1] 

机构地区：[1]清华大学热科学与动力工程教育部重点实验室,热能工程系,北京100084

出　　处：《工程热物理学报》2009年第2期295-298,共4页Journal of Engineering Thermophysics

基　　金：高等学校博士点基金项目(No．50003062);北京市教育委员会科技发展计划重点项目(No．kz200610016009)

摘　　要：本文建立了纳米颗粒/制冷剂工质换热性能实验台,对实验系统进行了检验,并首次进行了纳米颗粒TiO_2/HFC134a工质水平管内的单相对流换热实验研究,纳米颗粒的浓度为0.01、0.025和0.05 g/L,并与纯质HFC134a的结果相比较。结果发现:TiO_2/HFC134a工质的单相对流换热系数降低,且随着纳米颗粒浓度的增大,降低程度增大。分析原因纳米颗粒在换热表面的沉积是造成这一结果的关键因素。In this paper, a new experimental system was built up to investigate the heat transter characteristics of the nanoparticles and refrigerant mixtures. The convective heat transfer of the TiO2 nanoparticles and HFC134a mixtures were investigated with the concentration of nanoparticles ranging from 0.01 g/L to 0.05 g/L. The results indicated that nanoparticles decreased the convective heat transfer coefficient of the refrigerant, and the degradation increased with increasing nanoparticles concentration. The key factor is the surface deposition characteristics.

关 键 词：纳米颗粒TiO2 HFC134A 对流换热 表面沉积 

分 类 号：TK124[动力工程及工程热物理—工程热物理]