A sharp interface reduction for multiphase transport in a porous fuel cell electrode

2006 ◽  
Vol 462 (2067) ◽  
pp. 789-816 ◽  
Author(s):  
Keith Promislow ◽  
John Stockie ◽  
Brian Wetton
Keyword(s):  
Fuel Cell ◽  
Proton Exchange Membrane ◽  
Moving Boundary ◽  
Relaxation Times ◽  
Phase Interface ◽  
Gas Diffusion ◽  
Proton Exchange ◽  
Parabolic Differential Equations ◽  
Two Phase ◽  
A Free Boundary Problem

The gas diffusion layer in the electrode of a proton exchange membrane fuel cell is a highly porous material which acts to distribute reactant gases uniformly to the active catalyst sites. We analyse the conservation laws governing the multiphase flow of liquid, gas and heat within the electrode. The model is comprised of five nonlinear-degenerate parabolic differential equations strongly coupled through liquid–gas phase change. We identify a scaling regime in which the model reduces to a free boundary problem for a moving two-phase interface. On each side of the moving boundary the nonlinear system is well approximated by its linearization whose relaxation times are much shorter than the front evolution. Using a quasi-steady reduction, we obtain an explicit leading-order evolution equation for the free surface in terms of the prescribed boundary conditions.

A 3D Single-Phase Numerical Model for a PEMFC Stack

2009 ◽  
Author(s):  
Anh Dinh Le ◽  
Biao Zhou
Keyword(s):  
Fluid Flow ◽  
Fuel Cell ◽  
Proton Exchange Membrane ◽  
Single Phase ◽  
Single Cells ◽  
Three Dimensional ◽  
Gas Diffusion ◽  
Proton Exchange ◽  
Two Phase ◽  
Catalyst Layers

A single-phase, three-dimensional mathematical model has been constructed and implemented to simulate the fluid flow, heat transfer, species transport, electrochemical reaction, and current density distributions in a Proton Exchange Membrane Fuel Cell (PEMFC) stack with parallel-shaped channels. In this study, a complete PEMFC stack with 3 parallel single-cells including the membrane, gas diffusion layers (GDLs), catalyst layers, flow channels, and current collectors was taken into account. The reasonable numerical results show the detailed distributions of fluid flow and species concentrations in the channel and porous media, heat and current transports through the single cells in the stack. Furthermore, this successful modeling of a single-phase PEMFC stack would be a critical step to further develop a general two-phase PEMFC model that could investigate the water management and effects of liquid water on the performance of a fuel cell stack.

Numerical Simulation of Two-Phase Water Behavior in the Cathode of an Interdigitated Proton Exchange Membrane Fuel Cell

2009 ◽  
Vol 7 (1) ◽  
Author(s):  
Peng Quan ◽  
Ming-Chia Lai
Keyword(s):  
Fuel Cell ◽  
Flow Field ◽  
Proton Exchange Membrane ◽  
Gas Diffusion ◽  
Proton Exchange ◽  
Cell Design ◽  
Two Phase ◽  
Water Behavior ◽  
Phase Water ◽  
Exchange Membrane

As an alternative to traditional reactant flow field design, interdigitated flow field configuration is also of interest to fuel cell design engineers and academic researchers. In this work, the two-phase flow behavior inside the cathode of an interdigitated proton exchange membrane fuel cell, including both gas flow channel and porous gas diffusion layer, is numerically studied. The effects of variable design and operational parameters, including channel surface wettability and operating pressure, on water behavior are investigated. A Darcy’s law based porous media model is used for the simulation of the two-phase transport inside the cathode gas diffusion layer, and some interesting two-phase behaviors, such as liquid water distribution under different operating condition, are observed. Compared with the water transport characteristics of a serpentine flow field, the current study shows significant difference for an interdigitated configuration, in terms of two-phase water transport. Although the interdigitated design is generally not considered viable for practical applications in fuel cell, it does provide a convenient platform for fundamental studies of multiphase transport and valuable insights in fuel cell design and optimization.

scholarly journals Modeling the Effects of Using Gas Diffusion Layers With Patterned Wettability for Advanced Water Management in Proton Exchange Membrane Fuel Cells

2018 ◽  
Vol 15 (2) ◽  
Author(s):  
Jaka Dujc ◽  
Antoni Forner-Cuenca ◽  
Philip Marmet ◽  
Magali Cochet ◽  
Roman Vetter ◽  
...  
Keyword(s):  
Fuel Cell ◽  
Proton Exchange Membrane ◽  
Two Phase Flow ◽  
Gas Diffusion ◽  
Proton Exchange ◽  
Ex Situ ◽  
Phase Flow ◽  
Mechanical Compression ◽  
Two Phase ◽  
Exchange Membrane

We present a macrohomogeneous two-phase model of a proton exchange membrane fuel cell (PEMFC). The model takes into account the mechanical compression of the gas diffusion layer (GDL), the two-phase flow of water, the transport of the gas species, and the electrochemical reaction of the reactant gases. The model was used to simulate the behavior of a PEMFC with a patterned GDL. The results of the reduced model, which considers only the mechanical compression and the two-phase flow, are compared to the experimental ex-situ imbibition data obtained by neutron radiography imaging. The results are in good agreement. Additionally, by using all model features, a simulation of an operating fuel cell has been performed to study the intricate couplings in an operating fuel cell and to examine the patterned GDL effects. The model confirms that the patterned GDL design liberates the predefined domains from liquid water and thus locally increases the oxygen diffusivity.

scholarly journals Modelling of Humidity Dynamics for Open-Cathode Proton Exchange Membrane Fuel Cell

2021 ◽  
Vol 12 (3) ◽  
pp. 106
Author(s):  
Fengxiang Chen ◽  
Liming Zhang ◽  
Jieran Jiao
Keyword(s):  
Fuel Cell ◽  
Mass Flow ◽  
Proton Exchange Membrane ◽  
Flow Model ◽  
Transport Theory ◽  
Gas Diffusion ◽  
Proton Exchange ◽  
Operating Conditions ◽  
Output Performance ◽  
Exchange Membrane

The durability and output performance of a fuel cell is highly influenced by the internal humidity, while in most developed models of open-cathode proton exchange membrane fuel cells (OC-PEMFC) the internal water content is viewed as a fixed value. Based on mass and energy conservation law, mass transport theory and electrochemistry principles, the model of humidity dynamics for OC-PEMFC is established in Simulink® environment, including the electrochemical model, mass flow model and thermal model. In the mass flow model, the water retention property and oxygen transfer characteristics of the gas diffusion layer is modelled. The simulation indicates that the internal humidity of OC-PEMFC varies with stack temperature and operating conditions, which has a significant influence on stack efficiency and output performance. In order to maintain a good internal humidity state during operation, this model can be used to determine the optimal stack temperature and for the design of a proper control strategy.

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