Two Phase Flow Modeling of Wind Influences on Wave Breaking

University Of Maine, Orono ME

Investigators

Abstract

Wave-breaking is of critical importance for transferring energy from wind into the ocean, and for dissipating some of the energy contained in the wave field. However, the detailed, three-dimensional dynamics involved in this process is poorly resolved in numerical models. This project will improve a high-resolution modeling approach in which the motions in both the air and water side are represented in the same modeling framework, and the instantaneous location of the interface between the two sides is accurately captured as the wave evolves. This model will be applied to shoaling waves for the first time. The results from this study will lead to a fundamental understanding of the two-way coupling between air and water during wave breaking in the open ocean and the surf zone. It will significantly advance our understanding of the effect of oblique and opposing wind on breaking waves. The project will also include outreach efforts to students and general public about coastal issues and STEM areas. The research objective of this proposal is to investigate the energy dissipation during wave breaking with special attention to the influences of wind. The effect of oblique and opposing wind on breaking is currently poorly understood and will be examined in this study. Building upon the investigators previous experience in computational fluid dynamics modeling of violent free surface flow, a three-dimensional two-phase flow Navier Stokes Solver with a novel interface capturing scheme and Large Eddy Simulation model will be used to resolve the fully coupled dynamics of air and water at the interface of a breaking wave. This work will be the first attempt to investigate the evolution of air-sea interaction during wave breaking from deep to shallow water using a three-dimensional two-phase flow and a Large Eddy Simulation model. It will also be the first comprehensive study of air-sea interaction within the surf and swash zone and the effect of oblique and opposing wind on breaking waves. The results from this study will improve the parameterization of breaking induced energy dissipation, momentum and energy exchange between wind and waves and storm surge. The project will engage middle- and high-school girls, from rural areas of Maine and encourage them to careers in science and engineering through an established outreach program at University of Maine.