Breaking waves
In physics, a breaking wave is a wave whose amplitude reaches a critical level at which some process can suddenly start to occur that causes large amounts of wave energy to be dissipated. At this point, simple physical models describing the dynamics of the wave will often become invalid, particularly those which assume linear behavior.
The most generally familiar sort of breaking wave is the breaking of water surface waves on a coastline. Because of the horizontal component of the fluid velocity associated with the wave motion, wave crests steepen as the amplitude increases; wave breaking generally occurs where the amplitude reaches the point that the crest of the wave actually overturns. Certain other effects in fluid dynamics have also been termed "breaking waves", partly by analogy with water surface waves.
Current research projects for surface waves are: Breaking waves on beaches; an experimental and numerical study. This is lead by our staff Atle Jensen
Wave impact
Violent impact of water waves on structures will cause large damages from the huge forces from the waves. The impact create velocities and pressures that are a lot larger than kinematics and dynamics which are associated with ordinary gravity waves.
Current research projects for wave impact: Experiments and simulations of solitary wave impact of a vertical wall.
This is being lead by our staff Atle Jensen
Internal waves
Internal waves are gravity waves that oscillate within, rather than on the surface of, a fluid medium. They arise from perturbations to hydrostatic equilibrium, where balance is maintained between the force of gravity and the buoyant restoring force. A simple example is a wave propagating on the interface between two fluids of different densities, such as oil and water. Internal waves typically have much lower frequencies and higher amplitudes than surface gravity waves because the density differences (and therefore the restoring forces) within a fluid are usually much smaller than the density of the fluid itself. Internal wave motions are ubiquitous in both the ocean and atmosphere.
Current research projects for internal waves are: Investigation of breaking internal waves is lead by Professor John Grue from UiO
Slide generated waves
Impulse waves generated by falling rock masses can sustain huge amplitudes if the rock masses fall into a geometrically confined water body, such as dams, lakes and fjords. The potential disaster for settlements along the shore of such a confined water body is obvious if impulse waves can be generated in the vicinity. An example of such a disaster is the 1934 Tafjord rockslide, killing 34 people in the Tafjord settlement in Western Norway when a huge rock fell into the fjord.
Current research projects for slide-generated waves are: This is being lead by our staff Atle Jensen
Surface waves
It is difficult to give a general and precise definition on what wave motion is. But a wave is a signal that propagates from one position in a media to another with a characteristic speed. These waves can be very different and how they are generated is dependent on in which fluid they appear.
However, water waves can be caused by gravity or surface tension and surface waves in the ocean or the atmosphere can be generated by the earth’s rotation. Even though the properties are very different, a lot of the mathematical models that are used worldwide are the same.
Current research projects for surface waves are: Kinematics of steep waves by John Grue, Atle Jensen and Karsten Trulsen.
