The offshore industry, MARIN and the Universities of Groningen and Delft have worked together successfully in the development of the Volume of Fluid method ComFLOW to study complex free-surface flows around offshore structures.
Large steps forward have been made in previous projects, but there are still some challenges ahead, such as the large computational times and the too high artificial (numerical) dissipation of the waves. The ComFLOW-3 Joint Industry Project aims to continue the development of ComFLOW focusing on new functionality and its validation, and further improvement of present functionality. The objective of the JIP is: To further improve, develop and validate the ComFLOW program for complex freesurface flows in the offshore industry and make it useable for advanced engineering applications by improved functionality and speed-up of the algorithms. The following issues are therefore addressed in the ComFLOW-3 JIP:
- Possibility to model viscous effects in the flow near sharp corners, like bilge keels.
- The ability to study local flow problems by using a local, very dense grid (for example wave impacts on deck girders).
- Possibility to model the dynamics of mooring lines and their influence on motions of offshore structures.
- Validation of new functionality with model tests, which contents can be proposed by the participants.
Improvement of present functionality:
- Computational efficiency by applying parallelisation using multi-core PCs
- Computational efficiency by using better absorbing boundary conditions, which make it possible to use a small computational domain
- Better algorithms for wave propagation.
The project runs parallel to a research project financed by the Dutch government, which supports 3 PhD students, a post-doc and validation model tests. The results of this research project are made available to the ComFLOW-3 JIP.