摘要
为了探究含有Au纳米流体的二维太阳能体吸收式集热器的性能,采用控制容积法数值求解了太阳能集热器内部的温度分布,将集热器出口平均温度作为温升的衡量标准,分析了影响集热器温升和效率的主要因素。研究结果表明:集热器内光谱强度在Au等离激元共振波长(500 nm左右)处大幅衰减,证明了金属表面等离激元共振效应可大幅强化光谱吸收特性;集热器内光谱辐射吸收程度影响集热器温度分布,从而影响集热器温升和效率;采用纯水作为工作流体时集热器效率仅39.99%,添加Au纳米粒子比添加Ag纳米粒子具有更高的集热器效率,可达78.75%;流体流速主要影响集热器温升,集热器高度主要影响集热器效率;当流速为0.1 m/s时可获得最大集热器温升36.63 ℃,集热器高度为2.5 cm时可获得最高效率82.98%;粒径和集热器长度对集热器温升和效率影响均不大。
The control volume method is used to numerically solve the temperature distribution in the solar collector and to investigate the performance of a two-dimensional solar collector with Au nanofluids.The average temperature of collector outlet is taken as the measurement standard of temperature rise.The main factors affecting the temperature rise and efficiency of the collector are analyzed.The results show that the spectral intensity of the collector decreases greatly at the wavelength of Au plasmon resonance(about 500 nm),which proves that the effect of metal surface plasmon resonance can greatly enhance the spectral absorption characteristics,and that the degree of spectral radiation absorption in the collector affects the temperature distribution of the collector,thus affecting the temperature rise and efficiency of the collector;the efficiency of the collector is only 39.99%when pure water is used as the working fluid.Adding Au nanoparticles has higher collector efficiency than adding Ag nanoparticles,and the efficiency reaches 78.75%;the fluid velocity mainly affects the collector temperature rise,and the collector height mainly affects the collector efficiency.When the flow velocity is 0.1 m/s,the maximum collector temperature rise of 36.63 ℃is obtained,and when the collector height is 2.5 cm,the maximum collector efficiency of 82.98%is reached;particle size and collector length have little effect on the collector temperature rise and efficiency.
作者
张煜
侯予
陈良
ZHANG Yu;HOU Yu;CHEN Liang(School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an 710049, China)
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2020年第8期44-49,共6页
Journal of Xi'an Jiaotong University
基金
陕西高校青年创新团队支持计划资助项目。
关键词
等离激元共振
集热器
纳米粒子
光谱特性
光热转换效率
plasmon resonance
collector
nanoparticles
spectral properties
photothermal conversion efficiency
