Closure of discussion on Drag coefficient and fall velocity of nonspherical particles

The most commonly encountered particles in the areas of sediment transport, fluidization, sedimentation, etc. are nonspherical. The role of these particles can be ascertained only through the knowledge of drag coefficient and fall velocity. Graphical relationships for the determination of drag coefficient and fall velocity are available in the literature. The graphical relationships are less accurate because they are subject to errors of judgment. Furthermore, these relationships cannot be used for any analytical purposes. In 1954, Schulz et al. collected extensive data for the drag coefficient and fall velocity of nonspherical particles. Based on these data, empirical equations for the drag coefficient and fall velocity of nonspherical particles of natural and mechanical origin are derived from curve fittings and presented. It is hoped that these equations will find use in the analytical modeling of various engineering problems involving fluid-nonspherical particles interaction.