Classification methods in streaming fluids

Abstract

The following considerations refer to granulometric methods using for classification of the forces occurring in moving media. Since it is possible to work in either liquids or gases and in either gravitational or centrifugal fields, there are four main groups of methods; these can be further subdivided on the basis of the use of the counterflow or cross-flow principle. It is not our task to describe this entire field, known under the name of elutriation. Therefore, only those fields of elutriation will be presented which have importance for granulometric measurements and sample preparation, i.e. the problems of hydrocyclones and cyclone air separators as well as the greater part of centrifugal classifiers are excluded.