Session: 06-03-06 Fluid-Structure, Multi-body and Wave-body Interaction VI

Paper Number: 127734

127734 - Environmental Load on an Ocean Semisubmersible Structure in the Presence of Rogue Waves With Currents 

Renewable and low-carbon energy sources are critical to helping to reduce greenhouse gas emissions in the fight against global warming. One method for generating this renewable, low carbon energy is offshore wind farms. A consistent wind source is always dependable for carbon-free energy production, equipment performance, and operational safety. In contrast to on land, offshore wind velocities are often steady. All structures in the offshore areas are subjected to a variety of environmental loadings due to the presence of very large waves and strong currents that can have significant impacts on the operation cycles of such structures. The presence of large waves and strong currents, as well as their interactions with the structures, might produce hazardous operational circumstances for any ocean structures. The operation and safety of the existing structures may be more vulnerable especially when a large wave travels against a strong current and produces abnormally high rogue waves. In this study, the loadings on a semisubmersible structure (SS) due to the presence of large waves, strong currents, and their consequent interactions are considered. An internally developed numerical tool that uses 3D mass-, momentum-, and energy-balanced equations has been employed for numerical simulations. An implicit and explicit commercial code OrcaFlex^TM that uses lumped mass elements to streamline equations was utilized for the comparisons of some results. To explore numerous instances, settings for incident wave and current conditions were systematically changed in the simulations. The SS's geometry and still water depth were maintained constant. In the simulation the SS is anchored at the sea bottom with four mooring lines one from each column’s bottom. All simulations maintained the same SS geometry and air gap.

Presenting Author: Hasanat Zaman National Research Council Canada

Presenting Author Biography: Dr. Hasanat Zaman is a senior research engineer at the Ocean, Coastal, and River Engineering Research Center of the National Research Council Canada (NRC). He has been with the NRC for over 22 years and is involved in various research fields, some of which include ocean hydrodynamics, ocean structures, renewable energy, marine autonomous vehicles.

Authors:

Hasanat Zaman National Research Council Canada
Ayhan Akinturk National Research Council Canada