Author(s)

P. D. de Wet, B. M. Halvorsen, & J. P. du Plessis

Abstract

Upon analysis of a set of collected data of Newtonian flow through a porous medium, it is evident that asymptotes exist for some variable dependencies in the transition from packed to fluidised bed. The transition between such asymptotes is governed, amongst others, by parameters such as particle size, particle size distribution, superficial gas velocity and bed height. The powered addition to a power, s, of such asymptotes f0 and f∞, leads to a single correlating equation that is applicable over the whole range of flow rates, namely f s = f s 0 + f s∞. This procedure circumvents the introduction of ad hoc curve fitting measures in the cross-over regions between the asymptotes and subsequent, unwanted jumps in piecewise fitted correlative equations for the dependent variable(s). The aforementioned method of powered addition is applied to the experimental data and the outcomes are discussed.

Keywords