Dr Steve Howell (Abercus) and Dr Kevin Black (Partrac) will present the following scour study at the 8th International Conference on Scour and Erosion (ICSE 2016). The conference will take place 12-15 September 2016 in Oxford, UK.
A comparison of the computational fluid dynamics approach for the prediction of seabed scour behaviour with full‑scale survey data from an offshore installation
The obstruction caused by objects on the seabed can cause the tidal flow around them to accelerate, which can lead to scouring of the seabed. Excessive scouring can lead to structural instability and risks to infrastructure such as electrical interconnectors and cabling. A robust understanding of scour potential is, therefore, necessary.
The computational fluid dynamics (CFD) approach is, potentially, a powerful engineering simulation tool for predicting sea bed scour. As with any numerical modelling technique, however, confidence in the simulation approach must be achieved through comparison of the predictions with experimental datasets. Historically, most such comparisons have used laboratory scale experimental data sets for the purpose of CFD validation. Whilst this is extremely valuable, confidence in the approach can be further improved through comparison with good quality full‑scale data from the real environment.
The purpose of the current paper is two‑fold:
To present full‑scale experimental data for scour behaviour from offshore surveys around real structures
To compare this experimental data with CFD predictions for the scour behaviour, to demonstrate the suitability of the CFD approach for modelling offshore scour at full‑scale.
With respect to the full‑scale survey data the paper explores the use of state of the art approaches for the collection of field data on seabed mobility, bathymetric evolution and sedimentation and how strategic datasets can be collected within cost-effective frameworks. Novel approaches to monitoring and survey include the use of benthic flumes, specialised multiple beam sonars for autonomous long‑term monitoring, real‑time transmission of offshore data and calibration‑free sediment sensors.
With respect to the CFD modelling, a comparison of several alternative approaches is presented and the relative accuracy and the associated computational overhead of each approach is discussed. A framework for CFD modelling of seabed scour behaviour is suggested.
Computational fluid dynamics (CFD), numerical modelling, full‑scale experimental data, offshore survey data, comparison, validation.
Dr Steve Howell – Abercus
Riverside House, Riverside Drive, Aberdeen, AB11 7LH, UK
Dr Kevin Black – Partrac
Suite A10, Milburn House, Dean Street, Newcastle Upon Tyne, NE1 1LE, UK