Understanding Sediment Dynamics at a Shipwreck Site Using CFD Modelling

Abstract

Shipwrecks are important cultural heritage sites offshore. In many instances, given their often long-term emplacement on the seafloor, they offer natural laboratories to study complex interactions between human-induced obstacles and seabed dynamics. Such interactions and induced sediment mobility also pose significant threats to offshore engineering infrastructure, such as turbine monopile foundations. Traditional methods can struggle to capture the nuance of these processes, with real-world surveys measuring effects only after installation, and laboratory models suffering from scale-down inaccuracies. Computational fluid dynamics (CFD) modelling offers an effective means of investigating the effects of obstacles on seabed dynamics, and by using shipwrecks as proxies for infrastructure, it can utilize long-term datasets to verify its predictions. In this study, high-resolution temporal bathymetric data were used in, and to verify, CFD modelling to investigate the interactions between hydro- and sediment dynamics at a shipwreck site in a tidally dominated wreck site. From this comparison, simulations of bed shear stress and scalar transport correlate well with known areas of erosion and deposition, serving as a basis for future scour prediction studies and creating effective tools in offshore renewable infrastructure planning and de-risking.