Numerical investigations on transient behaviours of two 3-D freely floating structures by using a fully nonlinear method
- 158 Downloads
Two floating structures in close proximity are very commonly seen in offshore engineering. They are often subjected to steep waves and, therefore, the transient effects on their hydrodynamic features are of great concern. This paper uses the quasi arbitrary Lagrangian-Eulerian finite element method (QALE-FEM), based on the fully nonlinear potential theory (FNPT), to numerically investigate the interaction between two 3-D floating structures, which undergo motions with 6 degrees of freedom (DOFs), and are subjected to waves with different incident angles. The transient behaviours of floating structures, the effect of the accompanied structures, and the nonlinearity on the motion of and the wave loads on the structures are the main focuses of the study. The investigation reveals an important transient effects causing considerably larger structure motion than that in steady state. The results also indicate that the accompanied structure in close proximity enhances the interaction between different motion modes and results in stronger nonlinearity causing 2nd-order component to be of similar significance to the fundamental one.
Keywordsfully nonlinear interaction two floating structures transient behaviours potential flow QALE-FEM method
Unable to display preview. Download preview PDF.
- Dean RG, Dalrymple RA (1991). Water wave mechanics for engineers and scientists. World Scientific Publishing Co., Singapore, 170–187.Google Scholar
- Smith BG (2007). Extreme waves and ship design. 10th International Symposium on Practical Design of Ships and Other Floating Structures, Houston, USA.Google Scholar
- Yan S, Ma QW (2008). Numerical investigations on responses of two moored 3D floating structures to steep waves. Proc Int Offshore and Polar Engng Conf (ISOPE2008), Vancouver, Canada, 322–310.Google Scholar
- Yan S, Ma QW, Cheng X (2011a). Fully nonlinear hydrodynamic interaction between two 3D floating structures in close proximity. Journal of Offshore and Polar Engineering, 21(3), 178–185.Google Scholar
- Yan S, Ma QW, Cheng X (2011b). Fully nonlinear simulation of two floating structures in close proximity subjected to oblique waves. Proc Int Offshore and Polar Engng Conf (ISOPE2011), Hawaii, USA, 104–112.Google Scholar