Estimates of pressure gradients in PEMFC gas channels due to blockage by static liquid drops
| Autor: | J.W. Van Zee, Sung In Moon, Sirivatch Shimpalee, Murali Sankar Venkatraman, C.W. Extrand |
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| Rok vydání: | 2009 |
| Předmět: |
Pressure drop
Hydrogen Renewable Energy Sustainability and the Environment Chemistry Drop (liquid) Energy Engineering and Power Technology Thermodynamics Reynolds number Proton exchange membrane fuel cell chemistry.chemical_element Condensed Matter Physics Volumetric flow rate Contact angle symbols.namesake Fuel Technology symbols Pressure gradient |
| Zdroj: | International Journal of Hydrogen Energy. 34:5522-5528 |
| ISSN: | 0360-3199 |
| DOI: | 10.1016/j.ijhydene.2009.04.039 |
| Popis: | Numerical analyses are presented to explain the effect of drop size and contact angle on local pressures inside small channels. These pressures and channel characteristics are of interest when water condenses in the gas channels of Proton Exchange Membrane Fuel Cells and hence the study uses Reynolds numbers consistent with as typical utilization of reacting gases in 200 cm 2 flow fields (i.e., 200 < Re < 1500 and stoichiometries of 1.2‐2.0 at 1.0 A/cm 2 ). The analyses were performed using three-dimensional computational fluid dynamic techniques and the results show that pressure drops are minimal until the blockage was greater than 50%. As blockage increased further, due to larger drops or increased hydrophobicity, pressure drop increased. The results of a stagnant drop are supported by visualization experiments, which show minimal distortion of the drop for these low flow rates, small ratios, and hydrophobic contact angles. Proper scaling parameters and design criteria for microchannels validation experiments are presented. a 2009 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved. |
| Databáze: | OpenAIRE |
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