Optimal design and operation of dual-ejector PEMFC hydrogen supply and circulation system
Date
2022
Authors
Chen, Li
Xu, Keda
Yang, Zuyong
Yan, Zhen
Dong, Zuomin
Journal Title
Journal ISSN
Volume Title
Publisher
Energies
Abstract
A proton exchange membrane fuel cell (PEMFC) system requires an adequate hydrogen supply and circulation to achieve its expected performance and operating life. An ejector-based hydrogen circulation system can reduce the operating and maintenance costs, noise, and parasitic power consumption by eliminating the recirculation pump. However, the ejector’s hydrogen entrainment capability, restricted by its geometric parameters and flow control variability, can only operate properly within a relatively narrow range of fuel cell output power. This research introduced the optimal design and operation control methods of a dual-ejector hydrogen supply/circulation system to support the full range of PEMFC system operations. The technique was demonstrated on a 70 kW PEMFC stack with an effective hydrogen entrainment ratio covering 8% to 100% of its output power. The optimal geometry design ensured each ejector covered a specific output power range with maximized entrainment capability. Furthermore, the optimal control of hydrogen flow and the two ejectors’ opening and closing times minimized the anode gas pressure fluctuation and reduced the potential harm to the PEMFC’s operation life. The optimizations were based on dedicated computational fluid dynamics (CFD) and system dynamics models and simulations. Bench tests of the resulting ejector-based hydrogen supply/circulation system verified the simulation and optimization results.
Description
Keywords
hydrogen ejectors, dual-ejector system, PEM fuel cell, hydrogen supply and circulation, CFD simulation, optimal design, optimal control, Institute for Integrated Energy Systems (IESVic)
Citation
Chen, L., Xu, K., Yang, Z., Yan, Z., & Dong, Z. (2022). “Optimal design and operation of dual-ejector PEMFC hydrogen supply and circulation system.” Energies, 15(15), 5427. https://doi.org/10.3390/en15155427