Concentration gradient of reactants extending from reaction sites inward inlet periphery of fuel cells

Özgür Aydin, Hironori Nakajima

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Transport of reactants and products to/from reactions sites affects the electrochemical energy conversion performance of fuel cells substantially. At high reactant utilization rates, mass transport can be the performance limiting factor, resulting in significant variations of current and temperature, etc. in the active field. To overcome mass transport limitations, reactants can be supplied at high rates and proper flow fields can be designed, for both of which numerical simulations are quite valuable. In these regards, although the highest care is put on the transport of species within active area of cells/stacks, herein we show the onset of mass transport limitation in the inlet periphery, i.e., extension of the concentration gradient of reactants from reactions sites inward the inlet periphery at high reactant utilization rates. We clarify this phenomenon leaning upon the computational error appearing in the concentration profile of a microtubular Solid Oxide Fuel Cell (SOFC) while simulating its electrochemical performance. For eliminating this error in numerical studies of fuel cells, we propose and demonstrate a practical method. We also determine the critical ratio of consumed/supplied mass fluxes for evaluating relevant (reactant species) SOFC systems in terms of the mass transport limitation in their inlet peripheries.

Original languageEnglish
Pages (from-to)F365-F374
JournalJournal of the Electrochemical Society
Volume165
Issue number5
DOIs
Publication statusPublished - Jan 1 2018

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Renewable Energy, Sustainability and the Environment
  • Surfaces, Coatings and Films
  • Electrochemistry
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Concentration gradient of reactants extending from reaction sites inward inlet periphery of fuel cells'. Together they form a unique fingerprint.

  • Cite this