An air-cooled proton exchange membrane (PEM) fuel cell system is designed and under manufacture for telecommunication back-up power. To enhance its competence in various environments, the system thermal feature is optimized in this work via simulation based on a computational fluid dynamics (CFD) model.

The model is three-dimensional (3D) and built in the commercial CFD package Fluent (ANSYS Inc.). It makes the full-scale system-level study feasible by only considering the system essences with adequate accuracy. Through the model, the optimization is attained in several aspects. Firstly, structural sources of a notable thermal disparity under an extremely low environmental temperature (−40 °C) are identified. Secondly, system design modifications are explored including elimination of interruptions in the airflow, implementation of fins, relocation of the system fan, etc. At last, an operation setting, the intake airflow magnitude, is also studied for a more uniform airflow and in turn a suppressed temperature disparity inside the system. Following the guidelines drawn by this work on the system design and the operation setting, the air-cooled fuel cell system can be expected with better performances and a longer lifetime. In addition, this work demonstrates the effectiveness of a compact 3D CFD model in improving a fuel cell system design and operation.

气冷质子交换膜（PEM）燃料电池系统已设计并正在生产中，用于电信后备电源。为了增强其在各种环境中的能力，通过基于计算流体动力学（CFD）模型的仿真，在这项工作中对系统的散热功能进行了优化。

该模型是三维（3D）模型，内置在商用CFD软件包Fluent（ANSYS Inc.）中。仅考虑适当的系统本质，就可以进行全面的系统级研究。通过该模型，可以在多个方面实现优化。首先，确定了在极低的环境温度（−40°C）下具有显着热差异的结构源。其次，研究了系统设计的修改，包括消除气流中断，散热片的实现，系统风扇的重新安置等。最后，还研究了运行设置（进气流量大小），以实现更均匀的气流，进而抑制了系统内部的温度差异。遵循这项工作在系统设计和操作设置方面制定的指导方针，空气冷却的燃料电池系统有望获得更好的性能和更长的使用寿命。此外，这项工作证明了紧凑型3D CFD模型在改善燃料电池系统设计和运行方面的有效性。