One of the most popular models adopted to describe the gas transport in porous electrodes is the dusty-gas model (DGM). However, such a model is commonly applied under the assumption of uniform pressure, which is incompatible with the DGM formulation and does not allow fluxes to obey reaction stoichiometry. In such a case, the model fails to predict partial pressure profiles. In this study, the quantification of the error in the prediction of concentration overpotential, due the inconsistent assumption of uniform pressure, is obtained by simulating the gas transport in solid oxide fuel cell anodes in a broad range of conditions. Simulations show that an inconsistent use of the dusty-gas model may lead to relative errors in the prediction of concentration overpotential as large as 60%, especially in binary H2/H2O mixtures.
Dusty-gas model with uniform pressure: A numerical study on the impact of a frequent inconsistent assumption in SOFC electrode modeling
BERTEI, ANTONIO;NICOLELLA, CRISTIANO
2015-01-01
Abstract
One of the most popular models adopted to describe the gas transport in porous electrodes is the dusty-gas model (DGM). However, such a model is commonly applied under the assumption of uniform pressure, which is incompatible with the DGM formulation and does not allow fluxes to obey reaction stoichiometry. In such a case, the model fails to predict partial pressure profiles. In this study, the quantification of the error in the prediction of concentration overpotential, due the inconsistent assumption of uniform pressure, is obtained by simulating the gas transport in solid oxide fuel cell anodes in a broad range of conditions. Simulations show that an inconsistent use of the dusty-gas model may lead to relative errors in the prediction of concentration overpotential as large as 60%, especially in binary H2/H2O mixtures.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
