Peter Wellens defended his PhD-thesis succesfully

On Friday, January 13, Peter Wellens defended his PhD-thesis at Delft University of Technology, entitled “Wave simulation in truncated domains for offshore applications”.

The thesis is about simulating extreme wave impacts on offshore structures. For these simulations, a numerical method is used that is based on the Navier-Stokes equations. The software containing the method is called ComFLOW. It incorporates a cut-cell method to represent structures in the Cartesian grid computational domain and an improved Volume-of-Fluid method to displace the free surface.

The main subject of the thesis is an Absorbing Boundary Condition (ABC) for dispersive waves. An ABC for waves is required to reduce re-reflection of waves at domain boundaries in much the same way as Active Reflection Compensation (ARC) is used in Deltares’ experimental facilities such as the Scheldt flume. It is imperative, especially in longer irregular wave simulations leading up to a wave impact, that re-reflection of waves does not disturb the sea state that we are trying to represent in our model.

Deltares is a partner in the Joint Industry Project (JIP) ComFLOW-3. Our task is to supervise a PhD-student to continue the work on ABCs for waves and to develop improved methods for displacing the free surface. There is also a line of Strategic Research related to ComFLOW, in which we have extended the software with a porous flow module to represent the physics encountered in waves interaction with permeable structures such as breakwaters. In December of 2012 the point was reached that the market turnover exceeded the Strategic Research investment that was made, which was cause for a celebration in itself.