In this chapter, let us study how well the proposed mixing theories agree with the real world. After all, an effective description of matter is ultimately a project that grows from practical needs. As we have noticed in the earlier chapters, in none of the mixing models could the exact effective permittivity be derived with full rigour. Approximations had to be made in the analysis to be able to take into account the effect of the randomness of the structure on the dielectric interaction. Were those assumptions justified? The approximations earn their legitimation from the success of the mixing models in predicting macroscopic properties of heterogeneous media. Because dielectric data exist for many types of natural and human-made materials, it is time to ask what kind of averages of the components are the dielectric properties of these materials and how do they match against the models.
Applications to natural materials, Page 1 of 2
< Previous page Next page > /docserver/preview/fulltext/books/ew/pbew047e/PBEW047E_ch13-1.gif /docserver/preview/fulltext/books/ew/pbew047e/PBEW047E_ch13-2.gif