The European Physical Journal Special Topics

, Volume 153, Issue 1, pp 111–113 | Cite as

Photothermal deflection measurement of effective gas diffusion coefficient of a porous medium

  • J. H. Rohling
  • J. Shen
  • C. Wang
  • J. Zhou
  • C. E. Gu
Article

Abstract.

In this work, an effective gas diffusion coefficient of a porous medium was measured using photothermal deflection (PD) technique. An in-house made Loschmidt diffusion cell with a photothermal-deflection probe were employed to measure the effective gas diffusion coefficient of a gas diffusion layer (GDL) with a porosity ε ≈ 0.7. The concentration evolutions of CO2 in O2 with and without the GDL were measured, respectively, using a transverse normal PD technique. The concentration variations were used to deduce the gas diffusion coefficients in the presence and absence of the GDL by solving mass diffusion equations. The effective gas diffusion coefficient of the GDL was calculated from the diffusion coefficients using a model of an equivalent resistance to diffusion and found to be 4.39 × 10-6 m2s-1, demonstrating that PD technique can be employed to determine the effective gas diffusion coefficient of a porous medium.

Keywords

Porous Medium EUROPEAN Physical Journal Special Topic Ball Valve Bottom Chamber Equivalent Resistance 

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References

  1. J. Crank, The Mathematics of Diffusion, 2nd edn. (Oxford University Press, New York, 1975) Google Scholar
  2. J.H. Rohling, J. Shen, C. Wang, J. Zhou, C.E. Gu, Appl. Phys. B (in press) Google Scholar
  3. F. Zhang, R.E. Hayes, S.T. Kolaczwski, Trans. IChemE Part A 82, 481 (2004) Google Scholar
  4. J.H. Rohling, J. Shen, J. Zhou, C.E. Gu, A.N. Medina, M.L. Baesso, J. Appl. Phys. 99, 103107 (2006) Google Scholar
  5. T.R. Marrero, E.A. Mason, J. Phys. Chem. Ref. Data 1, 3 (1972) Google Scholar

Copyright information

© EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2008

Authors and Affiliations

  • J. H. Rohling
    • 1
  • J. Shen
    • 1
  • C. Wang
    • 2
  • J. Zhou
    • 1
  • C. E. Gu
    • 1
  1. 1.National Research Council of Canada, Institute for Fuel Cell InnovationVancouverCanada
  2. 2.Institute of Modern Optical Technologies, Suzhou UniversityJiangsuP.R. China

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