Modelling the influence of characteristics, orientation and positioning of beach buildings on airflow and aeolian sediment transport patterns in the surrounding area

Coastal zones worldwide have always been attractive to human populations because of their rich resources and recreational values. This leads to an increasing number of buildings at the beach-dune interface, such as hotels, restaurants, vacation houses and pavilions. Buildings at the beach locally change the airflow patterns in their surrounding area depending on their size, shape, orientation and positioning with respect to neighbouring buildings. These building-induced changes in wind flow field (speed and direction) alter aeolian sediment transport which, in turn, influence the morphologic patterns around
buildings. For beach buildings placed in front of the dunes, these forced bedforms around buildings could negatively affect the dunes by e.g. trapping the sediments upwind of the buildings slowing down the dune growth. Furthermore, a large amount of sediment deposition or an intense erosion around buildings cause malfunctions in buildings. Coastal managers are responsible to define regulations for the design and placement of buildings at the beach. Understanding the airflow patterns and aeolian sediment transport around buildings could help to gain most benefits from buildings at the beach in regard to steering more sediments to dunes, or minimising their negative influence on dunes growth. To achieve this aim, a numerical model is developed using OpenFOAM and the influence of several parameters on airflow structures, aeolian sediment transport patterns and bedform development around buildings is investigated.