The Supergen ORE Hub is pleased to present the next topic in our new webinar series sharing the latest insights and innovations in offshore renewable energy research and giving a platform to those working at the forefront of ORE research. Find out more about previous webinars and watch recordings here.
About the webinar
July’s 2024 Supergen ORE Hub webinar included two presentations from members of the ECR community from Dr Aristos Christou from Cardiff University, and Dr Pengpeng He from the University of Dundee. Dr Christou will be discussing highlights of the advantages of numerical simulations of floating structures in offshore environments and the benefit of large-eddy simulations (LES), followed by Dr He who will discuss research into an analytical approach to probabilistically estimate the pullout capacity of strip plate anchors in spatially variable soil.
Speaker: Dr Aristos Christou
Presentation title: Advantages of Numerical Simulations of Floating Structures in Offshore Environments
Abstract: Well developed and validated Numerical Wave Tanks (NWT) have demonstrated their ability to predict complex fluid-structure interactions and recently have been used to improve the efficiency of offshore devices to further exploit offshore renewable energy and reduce the impact of climate change. This presentation highlights the advantages of numerical simulations of floating structures in offshore environments and the benefit of large-eddy simulations (LES). The numerical results demonstrate the local flow hydrodynamics such as the vorticity field, the damping motion and water-surface fluctuations around floating structures. Visualizations of rotational flow structures and energetic eddies near the leading and trailing edges of a floating box interacting with periodic waves in intermediate water depths are presented to highlight the impact of turbulent flow on the functionality of floating devices.
Speaker: Dr Pengpeng He
Presentation title: Pullout Capacity of Offshore Anchors in Spatially Variable Soil
Abstract: Plate anchors have been recognised as an economical anchoring solution for floating offshore structures due to their higher capacity-to-weight ratios. The prediction of anchor pullout capacity often assumes a homogeneous soil with uniform properties over the entire soil mass. However, seabed soils typically exhibit significant spatial variability due to their geological history of soil formation. To account for this inherent spatial variability, this research proposed an analytical approach to probabilistically estimate the pullout capacity of strip plate anchors in spatially variable soil. In this study, the soil properties were represented by random fields, and an analytical framework was developed to estimate the first two moments and the probability density function of the anchor pullout capacity factor. The analytical approach was validated by the Random Finite Element Method (RFEM) over a wide range of soil and anchor parameters. Probabilistic charts were also developed to aid in the probabilistic analysis of anchor pullout capacity.
About the speakers
Dr Aristos Christou earned his PhD from University College London. During his PhD, he developed a Numerical Wave Tank (NWT) based on the Large Eddy Simulation (LES) method to study the interaction of waves with fixed structures and investigate the effect of waves, turbulence and depth varying currents in local flow hydrodynamics. Since 2022 he has been a post-doctoral research fellow at Cardiff University working on EPSRC wave energy project and his current research is funded by EPSRC funding from the eCSE project (ARCHER2-eCSE11-15) via ARCHER2 service at the University of Edinburgh. Part of his research is to further develop the open-source LES-based NWT, which will be later available to offshore renewable energy community, to study the interaction of waves with floating structures.
Dr Pengpeng He is currently Lecturer of Geotechnical Engineering in the Geotechnics Research Group at the University of Dundee. He obtained his PhD degree in Geotechnical Engineering from Western University, Canada, where he focused on the design of large wind turbine foundations. Following his PhD, he worked as a postdoctoral researcher at Dalhousie University, Canada, working on geotechnical code calibration and probabilistic analysis of geotechnical structures. His current research largely focuses on the design of offshore foundations/anchors, offshore site characterisation, offshore geotechnical uncertainty, reliability and risk, and the application of machine learning in offshore geotechnics.
