Modeling and simulation for PEM fuel cell performance optimization

在各种类型的燃料电池系统中，质子交换膜燃料电池（PEMFC）由于其效率高、设计简单、工作温度低等优点而备受关注。由于PEMFC设计迭代依赖于实验通常是非常昂贵和耗时的，计算机建模已成为一个有吸引力的研究方向，揭示有效的热和水管理策略是最重要的，在实现所需的性能和寿命的PEMFC操作。我们的初步努力已经建立了一个全面的三维PEMFC模型，考虑到热量和水的管理问题。作为我们正在进行的质子交换膜燃料电池研究工作的延伸，这里提出的项目将旨在将所有重要的物理和电化学过程中产生的质子交换膜燃料电池操作到一个完整的质子交换膜燃料电池模型，更现实地考虑多维，多物种，和多相非等温条件下的运输。为此，我们将特别注意三个新的成分：（a）水相变;（B）二阶电化学动力学;和（c）瞬态行为。由此产生的模型预计将是高度非线性和系统级的动态性质，成功的数值解，这将在很大程度上依赖于先进的数值技术。因此，除了质子交换膜燃料电池模型的发展，另一个流将展开对三维有限元网格自适应的后验误差估计，以响应复杂的流动模式和复杂的传输现象。这将代表自适应有限元方法的PEMFC计算机模拟的第一个应用程序，并帮助实现一个精确的数值解网格控制质量使用显着减少的计算资源。这两个研究工作流最终将合并，然后实施到商用CFD代码中。所得到的软件包有望为PEMFC研究人员提供有用的信息，并为PEMFC的设计、性能优化和成本降低提供有价值的见解和指导。

Among various types of fuel cell systems, proton exchange membrane fuel cell (PEMFC) has become promising owing to its high efficiency, simplicity in design, and low-temperature operating condition. Since PEMFC design iterations relying on experiments are usually very expensive and time-consuming, computer modeling has become an attractive research direction, revealing effective heat and water management strategies are of top importance in achieving the required performance and lifetime of PEMFC operation. Our initial efforts have been made to build up a comprehensive 3D PEMFC model with the heat and water management issue taken into account. As an extension of our ongoing PEMFC research work, the project proposed here will be aimed at incorporating all important physical and electrochemical processes arising during the PEMFC operation into a complete PEMFC model to more realistically account for multi-dimensional, multi-species, and multi-phase transport under non-isothermal conditions. For this purpose, our particular attention will be paid to three new ingredients: (a) water phase change; (b) second order electrochemical kinetics; and (c) transient behavior. The resulting model is expected to be of highly nonlinear and system-level dynamic natures, the successful numerical solution of which will strongly rely on advanced numerical techniques. Therefore, in addition to the steam of PEMFC model development, another stream will be unfolding towards 3D finite element mesh adaptation guided by the a posteriori error estimation in response to the complex flow pattern and sophisticated transport phenomena. This will represent the first application of adaptive finite element methods to the PEMFC computer simulation, and help achieve an accurate numerical solution on meshes of well controlled quality using a significantly reduced amount of computational resources. The two streams of research efforts will be eventually merging and then implemented into a commercially available CFD code. The resulting software package is expected to serve for the PEMFC researchers to obtain useful information and gain valuable insight and guidance for design, performance optimization, and cost reduction of PEMFCs.