Angular Velocity and Kinetic Energy Partitioning in a Saturated Saltation Cloud: High-Speed PTV Measurements

Saltation involves coupled particle translation and rotation. Particle rotation can potentially influence trajectory height, length, and energy exchange with the flow by generating a Magnus-type force. Previous studies report spin rates of hundreds of revolutions per second yet often simplify or neglect spin direction. Here, we use high-speed particle tracking to simultaneously resolve both the translational and angular velocities of saltating particles traveling within a saturated cloud. We focus on how spin direction and energy partitioning evolve with elevation and direction of motion, and speculate on what these changes imply for saltation dynamics.