METHOD TO PREDICT LONG TIME SPAN OF SCOUR AROUND OFFSHORE WIND TURBINE FOUNDATIONS

Martin Dixen, Iris Pernille Lohmann, Erik Damgaard Christensen

Abstract


A new method to predict scour development around offshore structures has been developed. The method has been tested on a monopile. The method consists of table of scour rates, which is used to predict the scour development around the structure at different stages of the scour hole. The scour rate tables have been made based on full 3D numerical simulations of the flow and sediment transport for fixed configurations of the scour hole. When changing the governing parameters which are causing the scour development around the structure, the erosion rate or backfilling rate can be calculated from the mass balance of the sediment. This leads to the scour rates tables that are used to analyses the development of the scour hole under different current conditions. The method has been tested against experimental scour data and showed very promising results.

Keywords


scour; monopile; CFD; current; sediment transport

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