复合纳米流体在直接吸收式太阳能集热器中光热特性的研究
Study on photothermal properties of composite nanofluids in direct absorption solar energy collector
张宇航 1周璐 1吉祝昊 1马红和1
作者信息
- 1. 太原理工大学电气与动力工程学院,山西 太原 030000
- 折叠
摘要
为研究用于直接吸收式太阳能集热器的二元Cu/SiO2 纳米流体的光吸收和光热转换,制备了PVP(聚乙烯吡咯烷酮)表面修饰的一系列不同组分的Cu/SiO2 复合纳米流体,并通过测量实验流体的透射率和闷晒实验,研究了水基复合纳米材料在不同情况下的光吸收和光热转换性能.结果表明,PVP浓度增加对纳米流体在反复加热情况下的热稳定性有明显增强作用,但存在最佳浓度使流体稳定效果达到最佳.闷晒实验结果表明,随着实验次数的增加,测得纳米流体的透射率逐渐升高,宏观表现为流体的稳定性变差、沉淀产生变多.通过复合纳米流体的光热转换实验并结合理论模型分析表明,二元Cu/SiO2 复合纳米流体的光热转换效率与Cu/SiO2 材料的复合比例关系密切且存在最佳复合比例使二者达到最大值.
Abstract
In order to study the light absorbing and photothermal conversion performances of binary Cu/SiO2 nanofluids that can be used in direct absorption solar collector,a series of Cu/SiO2 composite nanofluids with different components modified on the surface of PVP are prepared.The light absorbing and photothermal conversion performances of water-based composite nanomaterials under different conditions are studied through measuring the transmittance of the experimental fluid and conducting sun exposure experiments.Results indicate that an increase in PVP concentration significantly enhances the thermal stability of nanofluids under repeated heating,but there is a peak concentration that maximizes the fluid stability effect.Sun exposure experiment indicates that as the number of experiments increases,the transmittance of the measured nanofluid gradually increases,and the macroscopic manifestation is that the stability of the fluid deteriorates,and more precipitation occurs.Through the photothermal conversion experiment of composite nanofluids and theoretical model analysis,it is shown that the photothermal conversion efficiency of binary Cu/SiO2 composite nanofluids is closely related to the composite ratio of Cu/SiO2 materials,and there is an optimal composite ratio to achieve the maximum value of both.
关键词
纳米流体/稳定性/光热转换性能/表面活性剂/复合比例Key words
nanofluids/stability/photothermal conversion characteristics/surfactant/compositing ratio引用本文复制引用
基金项目
山西省应用基础研究计划项目(20210302123199)
出版年
2024
NETL
NSTL
万方数据