Terminal velocity and drag coefficient for spherical particles

Empirical correlations and experimental works relating the drag coefficient (C-D) of spheres to the Reynolds number (Re) and Re to the Archimedes number (Ar) were reviewed with a focus on the correlations applicable to the entire Re range. In addition, experiments with various spherical particles and fluids for the entire range of Re were conducted using high-speed video and added to the literature data. One of the correlations from the literature for Re-Ar and a modified correlation for C-D-Re were found to best fit the experimental results. The analysis also established new correlations for Re-Ha (a non-dimensional number for velocity not including particle size) and C-D-Ar. The latter is easier to use than the common C-D-Re curve. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The study reviewed empirical correlations and experimental works on the relationship between drag coefficient (C-D) of spheres with Reynolds number (Re) and Re with Archimedes number (Ar), and found the best-fit correlations for experimental results. New correlations for Re-Ha and C-D-Ar were also established, with the latter being easier to use than the common C-D-Re curve.