Page 14: of Maritime Reporter Magazine (August 2013)

14 Maritime Reporter & Engineering News ? AUGUST 2013 EYE ON DESIGNGeometry at the HeartComputational geometry is at the heart of much of MARIN?s day-to-day business Computational geometry is at the heart of much of MARIN?s day-to-day busi- ness, which includes the hull, appendages and propulsion design and optimization, to the milling of models and detailed CFD calculations. And computational geometry is also set to play a key role in longer-term re- search and development carried out by MARIN, its clients and partners.In 2012, MARIN started a new, long- term project to update and expand its geometry capabilities for hulls, append-ages and propellers. The aim is to en- able designers, CAD and CFD users to model and optimize their designs ef-fectively and interface them with the outside world: from geometry input to analysis, (CFD) calculations and model production.New propulsion design tools New tools were developed to design propellers and to generate suitable pro-peller geometry for panel and RANS codes. First, the well-known Rhinoc-eros 3D modelling suite was selected as the basis for the new CAD tools. Be-cause Rhino has a lot of out-of-the-box features, MARIN could focus on adding value and MARIN-speciÞ c functional- ity. MARIN was able to develop mul- tiple plug-ins for Rhino that are capable of reading and writing various propeller formats, showing the geometry on the screen and enabling the designer to ma-nipulate the propeller design. Accurate representations of propeller geometry could then be generated for detailed cal-culations using MARIN?s unstructured and unsteady RANS code ReFRESCO.Hull lines MARIN?s existing hull lines? design tool ?Geometry Modelling of Ships? (GMS), which has been in develop-ment for over 20 years, will also get a complete overhaul. Over the coming months and years, more and more func-tionality will be re-implemented and expanded as Rhino plug-ins using the current capabilities in GMS as a basis. Hull fairing, as applied in GMS, is one of these unique design capabilities that allow MARIN to design hundreds of hulls a year. There are simply no other tools available that give a designer such speed when drawing and fairing a hull. The existing knowledge and methods will be preserved in the new tools but further expanded with new, even more efÞ cient hull drawing and fairing func- tionality. Christian Veldhuis is project manager at the Ships depart- ment of MARIN, the Maritime Research Institute Nether- lands. MARIN offers simula- tion, model testing, full-scale measurements and training programmes, to the ship- building and offshore industry and governments. e: [email protected] MR #8 (10-17).indd 14MR #8 (10-17).indd 148/1/2013 9:02:38 AM8/1/2013 9:02:38 AM