British Reporter — Researchers studying wave breaking have found that axisymmetric ‘spike waves’ can far exceed limits that were previously thought to dictate the maximum height of ocean waves according to University of Oxford.
Researchers studying wave breaking have found that axisymmetric ‘spike waves’ can far exceed limits that were previously thought to dictate the maximum height of ocean waves.
Results from the wave tank demonstrated that axisymmetric wave breaking behaviour was very different to the wave breaking associated with travelling waves.
As the waves formed, a large vertical jet of water erupted from the crest of the wave before going into freefall and colliding with the surface of the water below.
The experiments showed that, unlike travelling waves, the crest height of the spike wave was not restricted by the onset of breaking but by the stability of the jet.
Dr McAllister said: ‘This study has revealed the fundamental mechanisms through which highly directionally spread and crossing waves can become much larger than other waves, accelerating upwards much faster than gravity for a short fraction of time.’
The new research at three orders of magnitude larger than previous experiments reveals significant implications for maritime safety. As Professor Ton van den Bremer, Engineering Science, University of Oxford and Delft University of Technology explains, ‘The spike wave is an idealised example of a type of behaviour that makes so-called crossing seas, where wave systems travel in different directions, so dangerous for shipping and offshore structures.’
Understanding the dynamics of the spike wave could ultimately lead to advances in maritime safety based on improved data on wave height limitations and breaking behaviour in extreme conditions, University of Oxford notes.
