Int J Thermophys (2010) 31:975–986
DOI 10.1007/s10765-010-0756-2
Generalized Bruggeman Formula for the Effective
Thermal Conductivity of Particulate Composites
with an Interface Layer
J. Ordóñez-Miranda · J. J. Alvarado-Gil ·
R. Medina-Ezquivel
Received: 16 June 2009 / Accepted: 13 May 2010 / Published online: 30 May 2010
© Springer Science+Business Media, LLC 2010
Abstract Combining the well-known Bruggeman theory and Nan et al. results,
formulas for predicting the effective thermal conductivity of anisotropic particulate
composites with an interface layer are derived. These formulas are valid for a compos-
ite material containing arbitrarily oriented ellipsoidal particles with any aspect ratio,
and they can be expected to be suitable mainly for large volume fractions, when the
thermal interaction between neighboring particles needs to be considered. Results of
the present approach are reduced to simpler formulas for some limiting cases in the
particle shape. Theoretical analysis of the effective thermal conductivity as a func-
tion of volume fraction and shape of the particles is performed. Comparison of the
obtained formulas with previously reported experimental data for the effective thermal
conductivity is also presented.
Keywords Bruggeman theory · Coated particles · Composite materials · Effective
thermal conductivity · Nan formula
1 Introduction
Composites materials have always attracted great interest, due to the fact that they
can inherit the desirable properties of its components while enhancing others. The
J. Ordóñez-Miranda · J. J. Alvarado-Gil (B ) · R. Medina-Ezquivel
Applied Physics Department, Centro de Investigación y de Estudios Avanzados del I.P.N-Unidad
Mérida, Carretera Antigua a Progreso km. 6, A.P. 73 Cordemex, 97310 Mérida, Yucatán, México
e-mail: jjag@mda.cinvestav.mx
J. Ordóñez-Miranda
e-mail: eordonez@mda.cinvestav.mx
R. Medina-Ezquivel
e-mail: rmedina.esquivel@gmail.com
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