Simulation and exergy analysis of a hybrid Solid Oxide Fuel Cell (SOFC)–Gas Turbine System
Simulation and exergy analysis of a hybrid Solid Oxide Fuel Cell (SOFC)–Gas Turbine System
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DOI：
10.1016/j.energy.2006.03.006
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发表时间：
2006-12
期刊：
影响因子：
9
通讯作者：
F. Calise;M. D. d’Accadia;A. Palombo;L. Vanoli
中科院分区：
文献类型：
--
作者：
F. Calise;M. D. d’Accadia;A. Palombo;L. Vanoli
本文对固体氧化物燃料电池-燃气轮机（SOFC-GT）混合动力系统进行了仿真和火用分析。在SOFC反应器模型中，假设只有氢参与电化学反应，堆的高温推动内部蒸汽转化反应完成；假定未反应气体在SOFC堆的下游燃烧室中被完全氧化。压缩机和燃气轮机是基于它们的等熵效率进行建模的。换热器和热回收蒸汽发生器均采用管中管逆流布置，采用热效率- ntu方法进行模拟。为了评估不可逆性和热力学低效率的分布，不仅要对整个工厂进行能量和火用平衡，还要对每个组件进行能量和火用平衡。对不同的操作压力、燃料利用系数、燃料-空气比、蒸汽-燃料比和电流密度进行了模拟。结果表明，对于1.5MW系统，使用适当的最重要设计变量值可以实现接近60%的电效率；特别是工作压力和电池电流密度。如果将热损失回收也考虑在内，则全球效率约为70%。
The simulation and exergy analysis of a hybrid Solid Oxide Fuel Cell–Gas Turbine (SOFC–GT) power system are discussed in this paper. In the SOFC reactor model, it is assumed that only hydrogen participates in the electrochemical reaction and that the high temperature of the stack pushes the internal steam reforming reaction to completion; the unreacted gases are assumed to be fully oxidized in the combustor downstream of the SOFC stack. Compressors and GTs are modeled on the basis of their isentropic efficiency. As regards the heat exchangers and the heat recovery steam generator, all characterized by a tube-in-tube counterflow arrangement, the simulation is carried out using the thermal efficiency-NTU approach. Energy and exergy balances are performed not only for the whole plant but also for each component in order to evaluate the distribution of irreversibility and thermodynamic inefficiencies. Simulations are performed for different values of operating pressure, fuel utilization factor, fuel-to-air and steam-to-fuel ratios and current density. Results showed that, for a 1.5MW system, an electrical efficiency close to 60% can be achieved using appropriate values of the most important design variables; in particular, the operating pressure and cell current density. When heat loss recovery is also taken into account, a global efficiency of about 70% is achieved.