Effective Permittivity of Mixtures: Numerical Validation by the FDTD Method

摘要

The present paper reports the results of an extensive numerical analysis of211u001eelectromagnetic fields in random dielectric materials. The effective permittivity 211u001eof a two-dimensional dielectric mixture is calculated by FDTD simulations of such 211u001ea sample in a TEM-waveguide. Various theoretical bounds are tested in light of 211u001ethe numerical simulations. The results show how the effective permittivity values 211u001elie between Wiener limits, and according to FDTD simulations the values are 211u001ealmost always between Hashin-Shtrikman limits. Calculated permittivity 211u001edistribution is also compared with theoretical mixture models. No model seems to 211u001ebe able to predict the simulated behavior over the whole range of volume 211u001efraction.