Optimization of an Electrochemical Gas Separation and Inerting System
Date
2022-06-17
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Journal of The Electrochemical Society
Abstract
Aircraft fuel tank inerting is typically accomplished by supplying nitrogen enriched air (NEA) into the ullage (volume of air above the fuel level in the tank). We have developed a novel on-board electrochemical gas separation and inerting system (EGSIS) to generate NEA for fuel tank inerting. EGSIS is an electrically powered system that functionally combines a proton exchange membrane (PEM) fuel cell cathode with an electrolyzer anode. Water management is important in such a PEM-based system because proton transfer requires proper hydration of the membrane. Extremes of both dryout and flooding conditions should be avoided for optimal EGSIS performance. Previous single-cell EGSIS experiments revealed that supplying liquid water at the anode will maintain sufficient membrane hydration even when the system is operated under dry cathode conditions. However, it was difficult to avoid flooding at low cathode air stoichiometries when parallel flow field channels were employed. Here, we implement various strategies to optimize EGSIS performance such as using serpentine and interdigitated flow field channels, as well as a double-layer gas diffusion layer with graded hydrophobicity to mitigate flooding and improve water management. We also present a theoretical analysis of various stack configurations for a practical EGSIS module.
Description
This article was originally published in Journal of The Electrochemical Society. The version of record is available at: https://doi.org/10.1149/1945-7111/ac76e1
Keywords
airplane fuel tank, air separation, inerting, nitrogen-enriched air, fuel cell, electrolyzer, optimization, stack, water management
Citation
Aryal, Utsav Raj, and Ajay K. Prasad. 2022. “Optimization of an Electrochemical Gas Separation and Inerting System.” Journal of The Electrochemical Society 169 (6): 063514. https://doi.org/10.1149/1945-7111/ac76e1.