矩形微流道内Cu/Al核壳结构纳米流体的导热性能  

Flow and heat transfer characteristics of Cu/Al core-shell nanofluids in rectangular microchannels

作　　者：汪靖凯 赵蕾[1] WANG Jingkai;ZHAO Lei(School of Building Services Science and Engineering, Xi'an University of Architecture and Technology,Xi'an 710055, China)

机构地区：[1]西安建筑科技大学建筑设备科学与工程学院,西安710055

出　　处：《功能材料》2021年第2期2131-2135,共5页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(51878535);国家科技部科技支撑计划资助项目(2014BAJ01B01)。

摘　　要：采用还原法制备Cu/Al纳米复合粉,以水-乙二醇为基液,制备不同质量分数的Cu/Al复合纳米流体。利用XRD、SEM、TEM对复合材料的相结构和微观形貌进行了表征,采用紫外-可见分光光度计和热物性分析仪测试了其稳定性,将其应用于矩形流道微通道散热器内,通过实验研究了不同质量分数纳米流体的导热性能。结果表明,采用原位置换还原法制备的Cu/Al纳米复合粉体具有核壳结构,在添加十六烷基三甲基溴化铵分散剂条件下,质量百分数为0.1%,0.3%,0.5%复合Cu/Al纳米流体均具有良好的分散稳定性;随着Cu/Al质量分数的提高,纳米流体的导热系数增大;相对于基液,当纳米粒子浓度为0.5%时,Cu/Al纳米流体导热系数在矩形微道内最大提高39.6%,传热性能显著增强。Cu/Al powders has been prepared by displacement method and Cu/Al nanofluids based on DI-water/ethylene glycol with diffenert nanoparticle mass fraction are prepared.The microstructure and morphology of the Cu/Al powders are investigated by X-ray diffraction(XRD),scanning electron microscope(SEM)and transmission electron microscopy(TEM).The stability of nanofluids is tested using light absorption method and the thermal property analyzer is used to measure the thermal conductivity of nanofluids.The prepared hybrid nanofluids are used to flow through rectangular microchannels.The effects of mass concentration on the heat transfer performance are studied.The analysis results show that this method can prepare the novel core-shell Cu/Al powders.Using CTAB as dispersing agent,the Cu/Al nanoparticles have excellent dispersion stability with the mass concentration of 0.1,0.3,0.5%and the thermal conductivity of hybrid nanofluids increases with the increase of nanoparticle mass fraction.The largest growth rate of the heat transfer coefficients runs up to 39.6%at a mass faction of 0.5%compared with the results of base fluid in rectangular microchannels,and the heat transfer performance of nanofluids is more strengthened.

关 键 词：Cu/Al核壳结构 纳米流体 制备 流动换热 

分 类 号：KT124