The Research Of Scour Mechanism And Numerical Simulation Of Trawl Resistant Seabed Basement On Sand Bed

The scour that occurs around trawl resistant seabed basement which was a formof on sand bed was a complex three-dimensional problems, now international anddomestic academics had been carried out several studies for scour mechanism ofsubmarine structure on sand bed, but if we want to get the accurate analysis andforecast, we should carry out a lot of work. The scope and depth of scour of thesubmarine structure was an important reference for the design of the seabed basement.A lot of domestic and international scholar and scientists and technologists havecarried out plenty of research about the scour around submarine structure on sand bed,such as prototype measurement, indoor model test and numerical simulation. They hadput forward a lot of empirical and semi-empirical formula, which were very significantto the research of scour. Numerical simulation which had unique advantages will playa vital role in the future research of scour around seabed basement on sand bed withthe development of computer hardware and CFD.In this paper, we using Fluent and FLOW-3D established the three-dimensionalmathematical model of external flow field and scour around trawl resistant seabedbasement on sand bed, and completed the numerical simulation of external flow fieldand scour on sand bed. The results showed that the mathematical model can besimulated the flow field morphology and scour pit changes around the trawl resistantseabed basement. The numerical simulation can vividly reflect the flow field andvortex system around trawl resistant seabed basement, and fully show the scoured pit’sforming process. The main conditions that affect the scour around trawl resistantseabed basement consist of flow conditions near the trawl resistant seabed basementand sediment conditions. By changing the two factors of the flow velocity andsediment particle size, this article had simulated the scour on sand bed and analyzedthe changes in the trend of maximum scour depth around trawl resistant seabedbasement with the two factors. The results which were practical show that the modelcan predict the scope and depth of the trawl resistant seabed basement sand scour. Theresults were important for long-term instrument posture prediction after laying the seabed basement, and had a guiding role in trawl resistant seabed basement design.