基于分布参数燃料电池模型的SOFC-GT混合发电系统模拟  

SOFC-GT hybrid system simulation using a distributed-parameter SOFC model

作　　者：史翊翔[1,2] 包成[3] 蔡宁生[1] 毛宗强[2] 

机构地区：[1]清华大学热能工程系,热科学与动力工程教育部重点实验室,北京100084 [2]清华大学核能与新能源研究院,北京100084 [3]北京科技大学热能工程研究所,北京100083

出　　处：《清华大学学报（自然科学版）》2011年第2期282-288,共7页Journal of Tsinghua University(Science and Technology)

基　　金：国家“八六三”高技术项目(2007AA05Z151);国家自然科学基金资助项目(50706019)

摘　　要：针对混合发电系统模拟需求,建立管式SOFC准二维分布参数模型,沿流道方向考虑传热、传质数学模型,沿电池厚度方向考虑电化学反应以及多孔电极中的多组分气体扩散。结合系统其他部件(燃气轮机、重整器、换热器等)模型,对某公司220 kW SOFC-GT混合发电系统进行模拟分析,模拟了参比工况电池参数分布,研究了可控参数(工作电压、入口燃料流率、燃料循环比率、旁路空气比率)对系统性能、状态点参数及电池参数分布的影响规律。结果表明:系统参比工况稳态运行效率在52%以上,过电位、电流密度和温度沿流道方向变化显著,明显呈现非线性趋势,燃料、固体、空气的温度也有较大差异,在系统运行特性分析中有必要采用分布参数模型以合理描述电池中发生的物理化学变化。High performance modeling and optimized components are important for the development of solid oxide fuel cell/gas turbine（SOFC-GT） hybrid systems.The first part of a two-part paper presents a distributed parameter SOFC model,which is appropriate for system simulations,based on mass,energy,and momentum balances along flow direction and mass,and charge balances across the electrode.The models are quasi 2-D models that enable integration of a micro-level SOFC model into a system-level model.The system model integrated SOFC model with other component models（gas turbine,reformer,heat exchanger,etc） and was validated using experimental steady state performance data for a 220 kW SOFC-GT hybrid system.The system is used to analyze the effects of the main controllable parameters（cell voltage,inlet fuel flow rate,fuel recirculation ratio,and bypass air ratio） on the system performance,state point parameter values and cell parameter distributions.The results show that the hybrid system efficiency at the reference operating conditions can exceed 52%.The polarization voltages,current density and temperature vary nonlinearly along the flow direction.In addition,there are large temperature differences in the fuel,solid structure and air which suggest that a distributed parameter SOFC model must be used for hybrid system modeling to accurately describe the physical and chemical processes.

关 键 词：固体氧化物燃料电池 燃气轮机 混合发电系统 

分 类 号：TM911.47[电气工程—电力电子与电力传动] TK14[动力工程及工程热物理—热能工程]