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Abstract: Understanding and parameterising the onset of, and energy dissipation within, breaking surface gravity waves are far from completely understood. In this seminar, I will present an inertial-scaling-based parameterisation aimed at constraining the energy dissipation rate in individual breaking waves, using experimental data collected in our double-ended wind-wave flume under varying wave group and wind speed conditions. The model proposed builds upon the existing physical argument from literature (Drazen et al. 2008), but extends the framework in which to better account for the overturning crest dynamics and subsequent two-phase flow evolution. It will be demonstrated that the energy dissipation rate can be effectively scaled using only local measurements of breaking wave geometry. Using this refined scaling, I will also touch on the long-standing question of predicting the strength of breaking (characterised by the breaking strength parameter, b). The results show that b exhibits a cubic dependence on local wave steepness, along with an additional dependence on crest-front steepness.

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