Within the DAMEN Group Computational Fluid Dynamics (CFD) is used at several entities at different geographically spread office locations. The use of CFD is widely spread in the maritime industry and, since a couple of years, the use of this technology is significantly increased within the DAMEN Group. Due to the nature of CFD computations, there is a need for High Performance Computing (HPC). After a few years of using a semi-customized solution and building experience, DAMEN has chosen to consolidate a new “fit-for-purpose” HPC simulation platform to accelerate the design and optimization of our boats.
Computational Fluid Dynamics (CFD) models the fluid flow with Navier-Stokes equations, accounting for their nonlinear nature, viscous and turbulent effects. It is a complete method in terms of physical modelling, where very little is left to assumptions. This allows it to be highly accurate and precise, but it also makes it very computationally expensive comparing to most engineering tools in the field.
The Navier-Stokes equations
Computational grid
At DAMEN, CFD is employed to predict ship hull resistance in calm waters, including basic sinkage and trim approximations and self-propulsion characteristics. Accuracy within 3% can be expected for calm water resistance in full scale, for a computational cost of around 100 – 300 core-hours for a single simulation. This means that the simulation is finished after 2 – 5 hours of wall-clock time. This makes it easy to compare and test various ideas early in the design.
Slamming effect
Hull-propulsor interaction
Wakefield behind the ship
Ample resources are needed such that a continuous amount of simulations can be performed simultaneously. While usage is highly fluctuating, it is preferred to find a fixed price agreement to mitigate the risks and to increase visibility. By choosing Gompute’s private cloud environment with fixed resources, DAMEN was able to reduce the cost of a simulation by 40% compared to the previous HPC solution. The number of cores is a result of a technical and economical optimum, fulfilling the usage profile of DAMEN. Extension of capacity is possible to cover up for temporary peaks of usage by means of additional nodes readily available on demand. The platform is also flexible, offering the possibility to reevaluate the needed capacity regularly to take into account use growth.
Fluctuating workload
The purpose of the HPC solution is to serve the different Research departments within the DAMEN Group with a common computational platform enabling collaboration and creating synergy within the company on the use of this technology. A complete HPC simulation platform consolidated in the cloud allows not only share computing power but also the workspace, ensuring real-time collaboration.
The simulation platform is administrated by appointed stakeholders and steered by the budget holders of the several Research departments
The platform features state-of-the-art computing power allowing to run larger simulations and capture more complex phenomena, resulting in better and more accurate results. Moreover, the high performance capabilities available in the platform help to reduce data transfer as now the very large pre- and post-processing tasks are performed directly in Gompute: from grid generation, numerical setup to post-processing.
With the ability to reduce total simulation time by the use of state-of-the art computing power and optimized resources, DAMEN has given CFD a new kick by using it in combination with design optimization tools to minimize resistance and improve the overall hydrodynamic performance of the hull.
With such computational power at their fingertips, the Damen R&D teams now have unlimited access to cutting-edge, state-of-the art solutions for the design and development of the vessels of tomorrow, no matter the design constraints and the level of customization.