光学学报, 2017, 37 (7): 0722002, 网络出版: 2017-07-10
积尘对槽式太阳能聚光器焦面能流密度分布的影响及聚光优化
Effect of Dust Accumulation on Focal Energy Flux Density Distribution of Trough Solar Concentrator and Concentration Optimization
光学设计 积尘 聚光特性 二次均光反射镜 槽式聚光 能流密度分布 optical design dust accumulation concentration characteristics secondary homogeneous reflector trough concentration energy flux density distribution
摘要
为研究灰尘对槽式太阳能聚光器光学效率和金属管能流分布的影响,从理论上分析了积尘对聚光器光学效率的影响,对槽式太阳能聚光镜积尘工况进行了模拟,应用蒙特卡罗光线追迹法和有限元体积对抛物槽式集热系统传热进行了分析,得到了金属管周向温差(CTD)和能流密度分布。结果表明,积尘对反射光线方向和金属管壁面能流影响较大,由积尘改变壁面能流密度的分布对CTD有一定影响。针对CTD对抛物槽式集热系统的影响,提出了在常规抛物槽式集热器基础上添加一个二次均光反射镜的方法,二次反射镜的添加使金属管周向能流分布趋于均匀,并使金属管的CTD显著降低,减小了积尘工况对聚光集热系统的影响,这一方法为抛物槽式太阳能聚光系统的优化提供了参考。
Abstract
In order to study the effect of dust on the optical efficiency of solar concentrator and the distribution of energy flow in metal tube, the influence of dust on the optical efficiency of the condenser is analyzed theoretically and the dusting conditions of the trough solar concentrator are simulated. Moreover, by analyzing the heat transfer of the parabolic trough collector system using the Monte Carlo ray tracing method and the finite element volume method, the energy flux density and circumferential temperature distribution (CTD) are generated. The results show that the accumulated dust has significant effect on the direction of reflected light and the energy flux density of the metal tube wall surface, and the distribution of the flow density of the wall by the dust has certain influence on CTD. According to the influence of CTD on the parabolic trough collector system, a new method is put forward that a secondary homogeneous reflector is added based on traditional parabolic trough collector system. The addition of the secondary reflector makes the energy flux distribution of the metal tube tend to be uniform and CTD of the metal tube of the new parabolic trough collector system reduce significantly, thus reducing the dust accumulated effect on the spot solar collector system. This method provides some reference for the optimization of parabolic trough solar concentrating systems.
闫素英, 常征, 王峰, 田瑞. 积尘对槽式太阳能聚光器焦面能流密度分布的影响及聚光优化[J]. 光学学报, 2017, 37(7): 0722002. Yan Suying, Chang Zheng, Wang Feng, Tian Rui. Effect of Dust Accumulation on Focal Energy Flux Density Distribution of Trough Solar Concentrator and Concentration Optimization[J]. Acta Optica Sinica, 2017, 37(7): 0722002.