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Bounds on the effective conductivity of two-dimensional composites made of n ≧ 3 isotropic phases in prescribed volume fraction: the weighted translation method

Published online by Cambridge University Press:  14 November 2011

V. Nesi
Affiliation:
Dipartimento di Matematica Pura ed Applicata, Universita' degli Studi de L'Aquila, 67010 L'Aquila, Italy

Abstract

We establish lower and upper bounds which are valid for the overall conductivity of twodimensional composites. They are based on a method which modifies the so-called translation method in a way which makes it effectively much more flexible. When specialised to composites of n > 2 isotropic phases, the new bounds are often strictly better than all the previously known ones. From the mathematical point of view, the improvement is due mainly to a new regularity result in p.d.e.s [2]. From the physical point of view the latter can be interpreted as a result bounding in a suitable sense the fluctuations of the ‘electric field’.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1995

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