计量学报2011，Vol.32Issue(4)：356-360,5.DOI:10.3969/j.issn.1000-1158.2011.04.15
磁性液体在均匀磁场中的瞬态双热线导热系数的测试
Measurement of Thermal Conductivity of Magnetic Fluids under External Uniform Magnetic Field Using Transient Hot-wire Method
摘要
Abstract
Polymeric a-olefin based magnetic fluids sealed in two glass tubes were placed in external magnetic field. To eliminate the end effect and the natural convection induced by magnetic field force and gravity force, the transient hot wire (THW) instrument was developed for accurate measurements of the thermal conductivity of magnetic fluids. The hot wire apparatus was calibrated utilizing distilled water and anhydrous alcohol as reference fluids, which showed that the experimental system has a high accuracy. Effects of the direction of external magnetic field to the magnetic fluids with different volume fraction of suspended magnetic particles were measured. Results indicated that: when the direction of external magnetic field was parallel to the heat flow (the temperature gradient) , the thermal conductivity of the magnetic fluid increased greatly. The conductivity increased almost linearly with the strength of the magnetic field, the higher the particle concentration, the more increment was. On the other hand, when the magnetic field was perpendicular to the heat flow, little change in the thermal conductivity was found.关键词
计量学/导热系数/磁性液体/均匀磁场Key words
Metrology/ Thermal conductivity/ Magnetic fluids/ Uniform magnetic field分类
通用工业技术引用本文复制引用
顾邦明,王正良,张立桥,陈善飞..磁性液体在均匀磁场中的瞬态双热线导热系数的测试[J].计量学报,2011,32(4):356-360,5.基金项目
浙江省科技攻关项目(2007C21025) （2007C21025）
宁波市自然科学基金(2008A610064) （2008A610064）
宁波市科技项目(2009B20059) （2009B20059）
