PACKAGE DEGREE, EFFECTIVE THERMAL CAPACITY AND EFFECTIVE THERMAL CONDUCTIVITY OF MULTI-GENERATION AND FRACTAL PARTICLE BEDS

摘要

The basic objective, which led to the presented models, was to obtain highest possible package degrees in packed beds with spherical particles. The method is to choose particles with substantially different diameters, e.g., by applying micro or nano fillers at the lower end of the diameter spectrum. The developed models, in the limit of an infinite number of particle generations N, lead to descriptions of fractal geometrical nature. The package degree, the effective specific thermal capacity and the effective thermal conductivity are modeled in detail. The main result of this work is the Fractal Conductivity Model (FCM), which is a self-similar continuation of the Maxwell-Eucken Model (MEM), the Improved Maxwell Model (IMM) and the Gonzo Model (GM). The results illustrate that the FCM for low N, where experimental data exist, agrees well and can be applied to numerically simulate the effective thermal conductivity, K_(eff), for 1 < N < ∞.