Will become a more integrated part of the design loop
CFD Marine performs advanced CFD analysis (Computational Fluid Dynamics) for the maritime sector. They are now investing in new software that will make their communication with ship designers more seamless.
“Normally, we get a virtual hull that we perform calculations on”, says Hans Jørgen Bjelke Mørch, Chief Executive Officer of CFD Marine.
“We have advanced computer programs that take into account sea currents using detailed geometry without simplifications in the calculations, that we previously used as standard. Models take into account both the air and water and make it possible to calculate any vessel. This method of calculating currents was first used in the aviation and automotive industries. We apply the same techniques, and now the methods we use are as accurate as when testing ship models in test tanks”, he continues.
Using a 3D CAD model, CFD Marine can test characteristics of the vessel without the presence of a physical model:
“The most common analysis we use is the calculation of the object’s resistance and progress in calm water, but we also get out a lot of other data such as currents around the hull and superstructure, as well as the wave pattern around the vessel.
“We often calculate the vessel’s behavior in waves to find additional resistance and loss of speed, as well as stresses on the hull from accelerations. Furthermore, we have begun to examine the vessel’s ability to maneuver in calm water and in waves.
Based on our calculations, ship designers make the necessary adjustments and then we compute the hull again. We don’t need to create a physical model; thus, it gives us a tremendous freedom to be able to test out various solutions in this way”, he asserts.
Previously, it could take weeks just to build the model that is to be tested. Today, we do not have to build any type of model. Instead, we get the answers almost immediately after loading all the parameters the analysis application needs. This requires far fewer resources, it’s faster and much more affordable.
Part of the design loop
The core tool that CFD Marine uses in its calculations is STAR-CCM +. It is this program which allows the actual flow analysis:
“We are currently in the process of implementing NX from Digitread. We opted for this because we need good tools that can communicate with our customers who use design software. Hence, we use NX as an auxiliary tool to be a part of the design loop”, he explains.
Around a year ago, Siemens PLM Software, which develops NX software, acquired the firm behind STAR-CCM+. Thus, STAR-CCM+ is likely to become an integral part of the Siemens PLM package. “We expect that the communication and integration between systems, which already works well today, will be even better in the future. It was one of the reasons behind our decision to invest in the NX software. Another important factor is that many of the major ship design communities in Norway also use NX”, Mørch adds.