Simple Equations to Calculate Fall Velocity and Sediment Scale Parameter

Abstract

This paper investigates and compares four simple, continuous equations that can potentially make useful estimates of fall velocity. These estimates span the range of laminar, transitional, and turbulent flow regimes. All equations take advantage of the fact that the fall velocity Reynolds number is a function of only one variable, the Archimedes buoyancy index. Adjusting the coefficients can make a significant improvement in the fit of these equations to data. In the commonly used beach equilibrium profile model,