本文对两种适用于高倍聚光发电供热（HCPV/T）系统的多槽道和微通道水冷换热器进行了实验研究。利用模拟热源模拟了HCPV/T系统中光伏电池工作时的热流密度，分别研究了流量、壁面温度和输入电压对两种换热器传热特性的影响，并利用传热学理论对两种换热器的特点进行分析，获得了两种换热器努赛尔数Nu与雷诺数Re的拟合经验公式。实验结果表明，微通道换热器在低流量下有较强的换热能力，但在高流量下，换热能力无法随流量增大继续提高；多槽道换热器在低流量下换热能力不佳，但在高流量下仍可随流量增大继续提高。
A multichannel and a mini channel water-cooled heat exchanger were proposed and their applications for highly concentrating photovoltaic/thermal (HCPV/T) system were experimentally studied. A simulated heat source was used to simulate the heat flux of a photovoltaic cell in an HCPV/T system, and the influence of the flow rate, surface temperature and input voltage on the heat transfer characteristics of two heat exchangers were studied. Besides, characteristics of the two heat exchangers were qualitatively analyzed by heat transfer theory. The fitting formula of the Nusselt number and the Reynolds number was obtained from the experiment results. Results showed that, the mini channel exchanger has stronger heat exchange capability in the condition of low flow rate, but the heat exchange capability would not increase with the increase of the flow rate in the condition of high flow rate. The heat exchange capability of the multichannel exchanger was poor, while it would increase with the increase of the flow in the condition of high flow rate.
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