This paper focuses some fundamental aspects of combined convective and microwave drying of prolate spheroidal solids. A transient mathematical modeling based on the diffusion theory (mass and heat balance equations) written in prolate spheroidal coordinates was derived and the importance of this procedure on the analysis of the drying process of wet porous solid, is also presented. Results pointed to the behavior of the moisture migration and heating of the solid with different aspect ratio. Solids with higher area/volume relationships dry and heat faster.
A disseminated sulfide ore is represented by a two‐component system in which metallically conducting prolate spheroidal particles (simulating elongated mineralization) are randomly scattered throughout an electrolytic host. The Helmholtz equations describing the spatial and frequency dependence of anions and cations in the electrolyte near the surface of a particle are solved in prolate spheroidal coordinates. Expressions for the frequency‐dependent dipole moment induced on the particle by external electric fields transverse or parallel to the long axis of the particle are found by examining boundary conditions related to electrochemical charge transfer between the metallic particle and the electrolyte. The dipole moments of individual particles can be used to determine the effective conductivity spectrum of the mixture as a whole via the simple Maxwell formula or a novel recursive calculation which is accurate for large‐volume fractions of particles. Examples of conductivity spectra from this electrochemical model incorporating elongated particles are presented, and comparison of results with appropriate experimental data indicates good agreement.
Generalized Sturmian Functions in prolate spheroidal coordinates
