Disputation: Christopher Lawrence

Doctoral candidate Christopher Lawrence at the Department of Mathematics, Faculty of Mathematics and Natural Sciences, is  defending the thesis Extreme Wave Statistics of Surface Gravity Waves over Bathymetry for the degree of Philosophiae Doctor.

Picture of the candidate.

Doctoral candidate Christopher Lawrence

The PhD defence and trial lecture will be partially digital and streamed directly using Zoom. The host of the session will moderate the technicalities while the chair of the defence will moderate the disputation.

Ex auditorio questions: the chair of the defence will invite the audience to ask questions ex auditorio at the end of the defence. If you would like to ask a question, click 'Raise hand' and wait to be unmuted.

Trial lecture

Prerecorded trial lecture:
"Numerical analysis and control of lift-based wave energy devices"

Main research findings

Rogue waves are unexpected and unusually larger waves than their surrounding and can be dangerous to ship and offshore structures. In normally distributed wave fields also known as Gaussian sea, rogue waves actually exist, but their population can be greatly enhanced when the sea state deviates from Gaussian. Extreme deviation from Gaussian can be provoked by non-uniform bottom as a wave field propagates into shallower water. In this work, I studied how water waves propagate through varying bathymetry. 
Recent experiments of long-crested irregular waves propagating over a shoal showed that the deviation from Gaussian statistics occurs in the velocity field and is different from deviations in the surface elevation. In my thesis work, I developed a numerical code that is able to predict wave propagation in variable depth including the velocity field. The flexibility of numerical simulation allows me to investigate different types of bottom topography with different incoming waves. These simulations are useful to design new experiments. It turns out that the statistics of the surface elevation and the velocity field can be qualitatively different.

 

Published Nov. 24, 2021 2:26 PM - Last modified Nov. 24, 2021 2:47 PM