基于磁性纳米流体的直接吸收式太阳能集热器的集热性能

Thermal Performance of Simulated Direct Absorbing Solar Collector with Magnetic Nanofluid

采用磁性纳米流体(MNF)作为直接吸收式太阳能集热器(DASC)的工作介质并研究了其集热性能。将通过超声辅助共沉淀法合成的Fe3O4纳米颗粒分散在乙二醇(E-G)中制备MNF。采用该MNF作为DASC的工作介质时,集热器的导热效率比单纯采用E-G作为工作介质时高,并且可在较低体积分数的条件下获得较高的导热效率。在工作介质的入口处添加磁场可以提高其导热效率。磁场和MNF的协同作用有利于提高DASC系统的集热效率。

This paper presents the thermal performance of a simulated direct absorbing solar collector(DASC)with the application of magnetic nanofluids as heat transfer media.Magnetic nanofluid was prepared with magnetite nanoparticles,which were synthesized viaan ultrasound assisted coprecipitation method,in ethylene glycol as heat transfer media in the DASC.The heat transfer efficiency of DASC using magnetic nanofluid was greater than that using pure ethylene glycol.The higher efficiency could be obtained at a lower particle volume fraction.In addition,the efficiency could be increased when a magnetic field was applied nearby the inlet of DASC.It is indicated that the use of both magnetic field and magnetic nanofluids in DASC could contribute to the heat transfer efficiency of the system.