Optimal bounds on electric-field fluctuations for random composites
نویسنده
چکیده
The electric field inside a two-phase composite is studied when the composite sample is subjected to a constant applied electric field. Upper and lower bounds on the covariance tensor of the electric field are found in terms of the effective dielectric properties of the composite. The lower bounds are shown to be optimal for two well-known families of microgeometries. Lower bounds on the covariance tensor are found when only the phase area fractions and the two-point correlation function are available. For statistically isotropic composites optimal lower bounds are derived when only the phase area fractions are known. © 2000 American Institute of Physics. @S0021-8979~00!02920-0#
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