The Numerical analysis of an anode-supported high temperature DIR-PSOFC operating conditions with considering the maximum allowable temperature difference

Document Type : Full Lenght Research Article

Authors

Faculty of Engineering, The University of Guilan

Abstract

In the present study, the operating conditions of an anode-supported high temperature direct internal reforming (DIR) planar solid oxide fuel cell (SOFC) are numerically analyzed. SOFCs are the energy conversion devices that produce electricity and heat directly from a gaseous fuel by the electrochemical combination of that fuel with an oxidant. A planar SOFC consists of an interconnect structure and a three-layer region often referred to as the PEN (Positive electrode/Electrolyte/Negative electrode) composed of two ceramic electrodes, anode and cathode, separated by a dense ceramic electrolyte.  A 1D mathematical model based on the species and the energy balances is conducted to investigate the concentration of the gas components in the channels and the cell temperature distribution in both solid structures and gas channels. In addition, the electrochemical model of the cell is applied to determine its performance parameters. A synthesis gas with 10% pre-reformed methane as fuel stream is fed to the cell and the water-gas shift, the methane-steam reforming and the electrochemical reactions are considered as mass and heat sources/sinks. The effects of the air ratio and the fuel utilization factor on the temperature field and the performance of the cell are examined through parametric analysis to determine the optimum operating conditions of the cell. The investigations are performed to ensure no cracking will occur due to cell crucial temperature difference. The results indicate that increasing the fuel utilization factor from 0.45 to 0.85 leads to increase the value of the maximum temperature difference across the PEN layer from 101K to 145K while it decreases from 177K to 124K by increasing the air ratio from 6.5 to 12.5. In order to achieve the maximum power density by considering the maximum allowable temperature difference across the cell, the value of the fuel utilization factor and the air ratio are obtained 0.85 and 9, respectively.

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References

[1]     Achenbach E. Three-dimensional and time-dependent simulation of a planar solid oxide fuelcell stack. J Power Sources 1994;49:333–48.
[2]      Ferguson JR, Fiard JM, Herbin R. Three-dimensional numerical simulation for variousgeometries of solid oxide fuel cells. J Power Sources 1996;58:109–22.
[3]      Iwata M, Hikosaka T, Morita M, Iwanari T, Ito K, Onda K, et al. Performance analysis of planar-type unit SOFC considering current and temperature distributions. Solid State Ionics. 2000;132:297-308.
[4]     Yakabe H, Ogiwara T, Hishinuma M, Yasuda I. 3-D model calculation for planar SOFC. J Power Sources 2001;102:144–54.
[5]      Aguiar.P, Chadwick.D, Kershenbaum.L, Modeling of an indirect internal reforming solid oxide fuel cell, Chem. Eng. Sci. 57 (2002)1665–1677.
[6]      Aguiar P, Adjiman CS, Brandon NP. Anode-supported high temperature direct internal reforming solid oxide fuel cell. I: modelbased steady-state performance. J Power Sources 2004;138:120–36.
[7]     Aguiar P, Adjiman CS, Brandon NP. Anode-supported high temperature direct internal reforming solid oxide fuel cell: II. Modelbased dynamic performance and control. JPower Sources 2005;147: 136–47.
[8]      Colpan CO, Dincer I, Hamdullahpur F. Thermodynamic modeling of direct internalreforming solid oxide fuel cells operating with syngas. J Hydrogen Energy 2007;32,787-795.
[9]      Meng Ni, Dennis Y.C. Leung, Michael K.H. Leung. Modeling of methane fed solid oxide fuel cells: Comparison between proton conducting electrolyte and oxygen ion conducting electrolyte J Power Sources 183 (2008) 133–142
[10]   Dong HyupJeon A comprehensive CFD model of anode-supported solid oxide fuel cells .ElectrochimicaActa 54 (2009) 2727–2736
[11]  Iwai H, Yamamoto Y, Saito M, Yoshida H. Numerical simulation of hightemperaturedirect-internal-reforming planar solid oxide fuel cell. Energy 2011:1–10.
[12]   Singhal SC, Kendall K, editors. High temperature solid oxide fuel cells: fundamentals, design and applications. Oxford: Elsevier; 2003. p. 12–7.
[13]   M.W. Chase, NIST-JANAF thermochemical tables, fourth edition, J. Phys. Chem. Ref. Data, Monograph 9 (1998) 1–1951.
[14]  Meng Ni, Dennis YC Leung, Michael KH Leung. Electrochemical modeling and parametric study of methane fed solid oxide fuel cells. J Energy Conversion and Management;2009.50.268- 278.
[15]  Bove, R. and S. Ubertini, Modeling Solid Oxide Fuel Cells: Methods, Procedures and Techniques. 2008: Springer.

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History

  • Receive Date: 08 February 2014
  • Revise Date: 24 April 2014
  • Accept Date: 29 December 2015

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