摘要
逆电渗析电堆(RED Stack)可以将自然界中广泛存在或通过人工方法制取的盐差能转换为电能。为了有效提高RED电堆的能量转换效率和输出电压,通过建立RED电堆能量转换模型,对采用溶液顺流流程的多个RED电堆(多电极)串联的RED发电系统进行理论研究,探讨RED流道总长,溶液流速以及RED电堆数对系统能量转换效率及输出特性的影响.计算结果表明:在设定参数下,降低溶液流速,增加流道总长和电堆数均能提升RED系统的发电效率.但随流道总长和电堆数继续增加,效率提升的趋势减缓.串联电堆在增加输出电压和功率密度的同时其总内阻随之增加,导致系统输出电流变化对输出电压和电堆功率密度的影响增大.
Reverse Electrodialysis stack(RED stack)can convert salinity gradient energy which exists widely in nature or can be made by artificial methods into electricity.To effectively enhance the energy conversion efficiency and output voltage,the model for RED stack energy conversion was developed,which can be used to research on the series multiple stacks(multiple electrodes)in a co-flow RED system.The effects of total flow passageway length of RED,solution flow velocity and series RED stack numbers on energy conversion efficiency and output characteristics of RED system were discussed.Simulation results show that under the given operation parameters,reducing solution flow velocity and increasing total flow passageway length and RED stack numbers can improve power generation efficiency of the system.But the growth rate will be down with flow passageway length and RED stack numbers increasing continuously.The increase of series RED stack numbers not only enhances the output voltage and power density of the system,but also improves the internal resistance,which leads to a significant influence of system output current on output voltage and power density.
引文
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