The role of computational fluid dynamics in understanding shipwreck site formation processes

摘要

Studies indicate that physical processes commonly dominate the initial stages of wreck site formation. Detailed knowledge and understanding of hydro- and sediment- dynamics are therefore imperative for studies dealing with site formation and in-situ preservation. In this investigation, the results of computational fluid dynamic modelling over a shipwreck site are presented, using a high-resolution surface derived from multi-beam echo-sounder data and boundary conditions constrained by field measurements (sediment samples and flow measurements). Simulation of the 3-dimensional flow velocity field around the wreck site, and secondary products derived from the computational model, confirm that flow velocity and turbulence are both amplified by the presence of the wreck, causing changes in the morphology of the flow regime. Flow contraction, the formation of lee-wake vortices behind the structure (accompanied by vortex shedding) and increased turbulence are all observed. Shear-stress and TKE amplification three to four times greater than ambient values are recorded downstream of the wreck structure. Benefits of this approach for studies of site-formation and in-situ conservation include the inexpensive, open-source, and desk-based nature of the investigation.