Xflow modelling for investigation of fluid structure interaction of artificial reef: application to burial effect

Abstract

Artificial reefs are presented as a possible response to the shrinking biological resource in coastal strip. They are intended to protect, regenerate, concentrate and enhance populations of marine organisms ( Miller et al ., 2007 ). The fluid-structure interaction generates changes in the flow regime, resulting in the formation of basins around the reefs by vortices above the structure ( Sumer et al ., 2001 ). The mean velocity correlated with the turbulent kinetic energy allows to study the sediment transport process in turbulent flow ( Mazzuoli et al ., 2020 ). Modelling of fluid-structure seabed interaction (FSSI) was realized on the software Xflow 2020. The evolution of the burial depth leads to an increase in the turbulent kinetic energy. This evolution correlates with the mean velocity and shows an evolution of the sediment transport in time. The dynamics of a saturated sand was supposed similar to a pseudo viscous fluid ( Chávez-Modena et al ., 2020 ; Ouda and Toorman, 2019 ; Zhou et al ., 2014 ). A two phases flow modelling with a sand defined by the Herschel-Buckley viscous model was realized. The result showed the same transport processes explained by ( Mazzuoli et al ., 2020 ). The innovation of this article is to highlight turbulence as the principal reason of reef burial. A predictive method to characterize structure burial during time was showed by multiphase modelling.