Experiment on performance of all-glass vacuum tube solar array heating system

doi:10.11975/j.issn.1002-6819.2017.11.031

	Experiment on performance of all-glass vacuum tube solar array heating system
	Li, Jinping1,2,3 ; Kong, Ying 1,2,3; Xu, Zhe 1,2,3; Si, Zetian 1,2,3
	2017-06-01
发表期刊	Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
ISSN	10026819
卷号	33 期号:11 页码:240-247
摘要	As a kind of conversion device of solar energy, the solar collector is the most important part of the solar heating system. Among various solar collectors, all-glass vacuum tube solar collector is regarded as more favourable than other collectors in both technical and economic perspectives, so domestic and foreign experts have studied several aspects of it. But the current studies usually focus on the heating performance of the solar system during the whole heating season and the influence factors of the collecting efficiency of the all-glass vacuum tube solar collector, and there is barely research on the hourly and dynamic heating performance of solar heating system in a monomer building under different operating ways. With the purpose of studying the above problems, an all-glass tube solar heating system is fabricated on a monomer building, combined with a low-temperature floor radiation heating. The system is composed of 6 groups of standpipe all-glass vacuum tube solar collectors which have uniform structure parameters, a low-temperature floor radiation heating device, a circulating pump, a valve, a conductor and other accessories. Every group of solar collector comprises 40 all-glass vacuum tubes with the external diameter of 58 mm and the length of 1 800 mm, and a storage tank with the volume of 400 L, which is installed on a rack with an angle of 45° facing south. The contour aperture area of solar collector is about 3.85 m2, so the total contour aperture area of the array is about 23.1 m2. The monomer building locates in Minqin County, Gansu Province, China. Its building area is 117 m2 and actual heating area is 87 m2. The operation mode of system is as follows: Daily 17: 30-23: 00 is set to be heating time; during this period, the controller controls the water pump to circulate hot water at a constant flow rate, stop for 5 min every operating for 8 min. In the experiment, the values of various parameters, such as the solar irradiance, the inlet and outlet temperatures of collector array, the tank water temperature, the ambient temperature, the circulating water flow rate and the wind speed, are measured by different sensors. All measured variables are collected and recorded automatically by Agilent 34970A data acquisition instrument every 10 s. The testing period was from November 24th to December 5th, 2015. Then, many important parameters such as the total heat loss coefficient of storage tank, the collection efficiency of solar collector array, the solar energy utilization and the solar heating fraction of the system, and hourly variation of building heat load are theoretically and experimentally investigated. Furthermore, in the actual operation state, the heating effect of the solar heating system is analyzed, and the improvement proposals of operating strategy are provided. The results show that the total heat loss coefficient of storage tank in this system is 25.82-31.53 W/, the collection efficiency of solar collector array is 38%-72%, and the solar energy utilization and the solar heating fraction of the system are 37.1% and 48.3%, respectively; only 54.6% of heat collected by the solar collector is used, the remaining heat is emitted to the environment, and thus the heat loss of system accounts for a large proportion of the total collected heat; under the actual operating state, the heat supply is much more than the heat consumption of building, and especially in the initial period of heating, heat supply reaches more than 10 times that consumed by building, and heat supply and heating time are excessively concentrated. As a consequence, improvement proposals of operating strategy are provided for the solar heating system of the monomer building to reduce the water flux of heating system and advance the heating time. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
关键词	Buildings Collector efficiency Data acquisition Digital storage Electron tubes Energy efficiency Energy utilization Enthalpy Floors Flow of water Glass Heat losses Heating equipment Instrument testing Monomers Solar cell arrays Solar energy Space heating Tanks (containers) Temperature Tubes (components) Water towers Wind Collecting efficiency Collection efficiency Constant flow rates Economic perspective Floor radiation heating Heat consumption of buildings Heating performance Solar heating system
DOI	10.11975/j.issn.1002-6819.2017.11.031
收录类别	EI
语种	中文
出版者	Chinese Society of Agricultural Engineering
EI入藏号	20173304046236
EI主题词	Solar heating
EI分类号	402 Buildings and Towers - 443.1 Atmospheric Properties - 446.1 Water Supply Systems - 525.2 Energy Conservation - 525.3 Energy Utilization - 619.1 Pipe, Piping and Pipelines - 619.2 Tanks - 631.1.1 Liquid Dynamics - 641.1 Thermodynamics - 641.2 Heat Transfer - 643.1 Space Heating - 657.1 Solar Energy and Phenomena - 702.3 Solar Cells - 714.1 Electron Tubes - 722.1 Data Storage, Equipment and Techniques - 723.2 Data Processing and Image Processing - 804 Chemical Products Generally - 812.3 Glass
来源库	Compendex
分类代码	402 Buildings and Towers - 443.1 Atmospheric Properties - 446.1 Water Supply Systems - 525.2 Energy Conservation - 525.3 Energy Utilization - 619.1 Pipe, Piping and Pipelines - 619.2 Tanks - 631.1.1 Liquid Dynamics - 641.1 Thermodynamics - 641.2 Heat Transfer - 643.1 Space Heating - 657.1 Solar Energy and Phenomena - 702.3 Solar Cells - 714.1 Electron Tubes - 722.1 Data Storage, Equipment and Techniques - 723.2 Data Processing and Image Processing - 804 Chemical Products Generally - 812.3 Glass
引用统计	无
文献类型	期刊论文
条目标识符	https://ir.lut.edu.cn/handle/2XXMBERH/114939
专题	能源与动力工程学院
作者单位	1.Western China Energy & Environment Research Center, Lanzhou University of Technology, Lanzhou; 730050, China; 2.China Northwestern Collaborative Innovation Center of Low-carbon Urbanization Technologies, Lanzhou; 730050, China; 3.Key Laboratory of Energy Supply System Drived by Biomass Energy and Solar Energy of Gansu Province, Lanzhou; 730050, China
第一作者单位	能源与动力工程学院
第一作者的第一单位	能源与动力工程学院
推荐引用方式 GB/T 7714	Li, Jinping,Kong, Ying,Xu, Zhe,et al. Experiment on performance of all-glass vacuum tube solar array heating system[J]. Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering,2017,33(11):240-247.
APA	Li, Jinping,Kong, Ying,Xu, Zhe,&Si, Zetian.(2017).Experiment on performance of all-glass vacuum tube solar array heating system.Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering,33(11),240-247.
MLA	Li, Jinping,et al."Experiment on performance of all-glass vacuum tube solar array heating system".Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering 33.11(2017):240-247.