Two-Phase and Non-Newtonian Flows

Abstract

Two-phase turbulent flow covers an enormous range of technically important situations. The two phases can be solid/fluid or fluid/fluid; if the former, the solid phase may be flexible or rigid, spherical or non-spherical. The concentration of one phase in the other may be such that individual morsels of one phase may be regarded as isolated, or such that adjacent morsels interact strongly. The characteristic dimensions of the distribution of one phase in the other may be such, relative to the dimensions characterizing the flow, that the two-phase mixture may be regarded as a continuum, or not. Most of these situations are extremely complicated, and relatively little of a scientific nature has been done, the literature consisting for the most part of the results of observation organized by dimensional reasoning and empirical models. In the space available here, we will be able to give detailed attention only to the simplest case, that of rigid, spherical particles, separated sufficiently to be considered isolated, and small enough so that the flow in their vicinity may be taken as simple. However, we will outline some of the considerations which are relevant to the other, more complicated cases.