Prediction of the settling velocity of irregularly shaped particles

This work presents a new empirical relationship between Reynolds number Re, and Archimedes number Ar. From this relationship it is possible to calculate the free settling (terminal) velocity of irregularly shaped (e.g. crushed) solids in water. Experimental terminal velocities for various size fractions from earlier works were correlated with the new equation. The data refer to crushed quartz and galena particles. The new relationship gives for a very wide range of Archimedes numbers (flow regimes) a good correlation between experimental and calculated terminal velocities. Comparisons with the Ganguly relationship also showed a good agreement for the prediction of the terminal velocities. The current work shows that the terminal velocities in water can be calculated with a single equation for various irregularly shaped solids and for various size fractions. (C) 2001 Published by Elsevier Science Ltd. All rights reserved.