Boundary layer dynamics and sediment transport in swash interactions

This project will explore the water motions that result from the wave that runs down a beach slope as it encounters the next wave coming up. This interaction will be investigated in the zone of the beach that is wetted and dried by waves after they break, technically known as the swash zone. Water motion interactions produced by oppositely moving waves will be studied with laboratory experiments in a wave flume.

Experiments will measure, in detail, flows near the sandy bottom, where sand becomes suspended in the water column. These processes determine whether a beach erodes or becomes wider; whether it steepens or flattens. The study will provide information for future efforts to emulate beaches with mathematical models.

The project will support one PhD student and 6 undergraduate research interns. The interns will be recruited from underrepresented groups through a program in the college of engineering at UW-Madison. Undergraduate interns will design demonstrations on ocean waves for “Science Saturdays,” which are activities geared toward K-12 students.

This project will study wave-driven flow interactions at the swash zone of the beach. Interactions will be studied with laboratory experiments (in a wave flume) that include successive solitary waves. Experiments will be designed to measure boundary layer dynamics and sediment resuspension.

Flow interactions determine the accretion vs erosion balance at the beach and shape the morphology of the beach. The study will propose parametrizations of sediment transport at the swash zone and provide information for future validations of numerical models. The project will support one PhD student and 6 REUs that will be recruited from underrepresented groups through a program in the college of engineering at UW. Undergrads will design demonstrations for “Science Saturdays,” geared toward K-12 students.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.