Dynamics of Autohumidifed PEM Fuel Cell Operation
Dynamics of Autohumidifed PEM Fuel Cell Operation
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自动加湿质子交换膜燃料电池运行动态
DOI：
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发表时间：
2006
期刊：
影响因子：
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通讯作者：
J. Benziger
中科院分区：
文献类型：
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作者：
Warren H. J. Hogarth;J. Benziger
报道了一种干馈式自增湿聚合物电解质膜燃料电池（PEMFC）的启动和对负载变化的动态响应。燃料电池电流可以通过注水点燃;所需注水的标准是根据燃料电池尺寸、温度和反应物进料速率推导出来的。观察到稳态多重性，其中燃料电池电流可以是高的（“点燃”）或低的（“熄灭”），具有相同的流速，温度，压力和负载。不同的稳态电压，获得相同的电流取决于操作历史。稳态多重性是由于膜阻力和产水量之间的正反馈。膜水含量由产生的水和通过对流除去的水的平衡确定。当产生的水大于其去除量时，发生电流点燃，使膜水合;当产生的水小于其去除量时，发生电流熄灭，使膜脱水。通过使用质量平衡和本构方程，设计标准的尺寸和操作的自增湿PEMFC。
Start-up and dynamic responses to changes in load are reported for a dry feed, autohumidified polymer electrolyte membrane fuel cell (PEMFC). The fuel cell current can be ignited by water injection; criteria are derived for the required water injection as functions of fuel cell size, temperature, and reactant feed rates. Steady-state multiplicity is observed where the fuel cell current can be either high ("ignited") or low (" extinguished") with the same flow rates, temperature, pressure, and load. Different steady-state voltages were obtained for the same current depending on the operational history. The steady-state multiplicity results from a positive feedback between the membrane resistance and water production. Membrane water content is determined from the balance of water produced and water removed by convection. Current ignition occurs when the water produced is greater than its removal, hydrating the membrane; current extinction occurs when the water produced is less than its removal, which dehydrates the membrane. Through the use of mass balances and constitutive equations, design criteria are obtained for sizing and operating autohumidified PEMFCs.