Elsevier

Chemical Engineering Science

Volume 65, Issue 6, 15 March 2010, Pages 2255-2257
Chemical Engineering Science

Shorter Communication
A general correlation for mass transfer in isotropic and anisotropic solid foams

https://doi.org/10.1016/j.ces.2009.12.016Get rights and content

Abstract

Many open-cell foams exhibit ellipsoidal rather than spherical cells. The extent of the anisotropy of the structure typically increases with decreasing cell density. In dimensionless transport correlations, an anisotropy factor has to be introduced in order to lend them general applicability. This paper reports on such a correlation for mass transfer which has been proven to be useful for ceramic and metallic foams with pore counts between 10 and 45 ppi and porosities between 75% and 95%. Based on this novel correlation it was also possible to apply successfully the Lévêque equation which enables the prediction of mass transfer coefficients from pressure drop data.

Section snippets

Notation

a, b, cpore lengths, m
U0superficial velocity, m/s
εhouter porosity, dimensionless
HgHagen number
ReReynolds number
ShSherwood number
ScSchmidt number

Acknowledgments

This project was financed by the German Research Foundation (DFG) in the frame of the Research Group FOR 583: “Solid Sponges—Application of Monolithic Network Structures in Process Engineering”.

References (6)

  • J. Zeschky et al.

    Polysilsesquioxane derived ceramic foams with gradient porosity

    Acta Materialia

    (2005)
  • T. Dillard et al.

    3D quantitative image analysis of open-cell nickel foams under tension and compression loading using X-ray microtomography

    Philosophical Magazine

    (2005)
  • L.J. Gibson et al.

    Cellular Solids: Structure and Properties

    (2001)
There are more references available in the full text version of this article.

Cited by (18)

  • Interfacial heat and momentum transfer relation for porous media

    2018, International Journal of Thermal Sciences
    Citation Excerpt :

    In fact, the equations proposed in the literature do not take into account the frictional coefficient (xf) which is the part of the friction factor due to the viscous friction only. Moreover, Garrido et al. [25,26] and Dietrich [11] did not consider the longitudinal dimension (l) from the physical point of view, or more precisely: the distance, at which the laminar flow develops within the foam structure. The above sections have shown a few problems to be clarified in order to elucidate the transfer and friction mechanisms occurring in solid foams.

  • Heat transfer performance of structured catalytic reactors packed with metal foam supports: Influence of wall coupling

    2016, Catalysis Today
    Citation Excerpt :

    For the foam herein investigated the same value εT = εH = 89.7% was obtained [13], thus no inaccessible void space was identified. Concerning the thermophysical properties, the density of the metal foam is 2.70 g/cm3 [29] and the heat capacity is 903 J/(kg K) measured at room temperature. The thermal conductivity of the Al alloy is assumed to be constant in the investigated temperature range at a value of 218 W/(m K).

  • CFD modeling of catalytic reactions in open-cell foam substrates

    2016, Computers and Chemical Engineering
    Citation Excerpt :

    Furthermore, better performances are observed also in terms of a reduction of the ratio between pressure drop and reactant conversion. From a literature survey, it results that the properties of foams have been experimentally investigated in several works and correlations for the pressure drop (Boomsma and Poulikakos, 2002; Skibinski et al., 2015), heat-transfer (Giani et al., 2005; Peng and Richardson, 2004) and mass-transfer have been proposed (Giani et al., 2005; Incera Garrido and Kraushaar-Czarnetzki, 2010). Along with experimental investigations, CFD approaches have been applied in order to enhance the understanding of the physical phenomena occurring at the micro-scale.

  • Hydrodynamics and mass transfer in a tubular reactor containing foam packings for intensification of G-L-S catalytic reactions in co-current up-flow configuration

    2016, Chemical Engineering Research and Design
    Citation Excerpt :

    Open cell solid foam (OCSF) can be considered as a promising alternative to fixed beds and monoliths due to their low pressure drop (high voidage in the range of 90%), their good thermal characteristics (for SiC or metallic foams), their good radial mixing and their high external specific surface area. These were the main drivers to divert OCSF from their initial applications like heat exchanger internals or light weight mechanical structures, to use OCSF as structured catalyst supports mainly for gas–solid reactions (Richardson et al., 2003; Bianchi et al., 2012; Giani et al., 2005; Groppi et al., 2007; Incera-Garrido and Kraushaar-Czarnetzki, 2010; Lacroix et al., 2007; Montebelli et al., 2014; Patcas et al., 2007). However, these potential advantages can also be of great interest in reactive three-phase systems.

  • Performance of randomized Kelvin cell structures as catalytic substrates: Mass-transfer based analysis

    2014, Chemical Engineering Science
    Citation Excerpt :

    The correlation was qualitatively in very good agreement with that observed by Incera Garrido and Kraushaar-Czarnetzki (2010).

View all citing articles on Scopus
1

Present address: Pemex, Centro de Ingeniería y Geociencias, Edificio Kaxan, 1er Piso, Sala 2, Carretera Carmen-Puerto Real, Km. 4.5, Cd. del Carmen, Campeche, Mexico

View full text