Jiansheng Xiang, John-Paul Latham, Axelle Vire, Elena Anastasaki, Christopher C. Pain


FEMDEM modelling which combines the multi-body particle interaction and motion modelling (i.e. Discrete Element Model, DEM) with the ability to model internal deformation of arbitrary shape (Finite Element Model, FEM) has been applied to breakwater models. There are two versions of a FEMDEM solver developed; Y3D_D is for deformable materials and is required for dynamic and static stress analysis and Y3D-R is the rigid version often used to numerically construct the armour unit packs. This paper also reports the placement protocols: POSITIT.
FEMDEM modelling deals with solids interactions and is one modelling component that is to be coupled to other modelling technologies e.g. CFD, interface tracking, wave models, porous media etc. so that the key fluid-solid interactions can be modelled in a full scale virtual breakwater alongside work on scaled hydraulic laboratory models and prototype structures. The latest developments of two-way coupled interactions of waves with coastal structures are also described in this paper.


rubble-mound breakwater; fluid-structure interaction; combined finite-discrete element method

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