High Instantaneous Efficiency and High Flow Rate Slotted-Plate Solar Collectors

Abstract:

With the highlight of less regards to insulation measures and the key factor of the flow rates, slotted-plate solar collectors possess rather lower thickness and lighter mass, higher heat production, and better matching with various buildings compared with the common plate solar collectors. Results show that a much higher instantaneous efficiency could be obtained by increasing the flow rates suitably in a low-temperature working environment. The average efficiency could reach up to 51% with the maximum instantaneous efficiency of 61%. Based on the analysis of the relation between instantaneous efficiency and flow rates or the relation between instantaneous efficiency and the temperature difference of the inlet and the outlet water, a experiential formula for the optimal flow rate is proposed to improve the heating-up rates and working efficiency. The performances investigation of slotted-plate solar collectors would pave a way for their widespread and positive applications in the near future.

• Periodical: Advanced Materials Research (Volumes 860-863)
• Pages: 88-92
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.860-863.88
• Online since: December 2013
• Authors: Zhen Xing Zhang*, Yong Min He, Xiao Dong Li, Jin Yuan Zhou, Xiao Zhi Liu, Er Qing Xie
• Keywords: Instantaneous Efficiency, Optimum Flow Rates, Slotted-Plate Solar Collectors

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