Please can someone outline the basic requirements of 3d models used for stability and hydrostatics in Maxsurf?
It should be NURBs - .IGES with one closed surface?
how complex can the model be?
can it take other file formats like ,obj or mesh?
Sorry if this is a very basic question I am new to the software and have not yet found where these questions are answered in the documentation if you could direct me I would be most grateful.
hi Ben you need to load the model in Modeler first to set it up for hydrostatics calculations in Stability. There are many file formats that Modeler will accept. You can use NURBS surfaces, mesh surfaces or a combination of the 2. For hysrostatics, any section through the model should form closed, non-intersecting and non-self-intersecting contours. Please refer to the Modeler manual and Stability manual for more details:
these videos should also help explain what to check:
(186) MAXSURF Stability - Hull Model Analysis - YouTube
(186) Combining both NURBS and Trimesh surfaces in a MAXSURF design file - YouTube
Hi Pat, Thanks for your help here. We don't run Maxsurf we supply models to a client who uses it for damaged stability calculations. So we don't have access to Modeller. At the moment I have a steps model created by trimming surfaces back. I have checked it using Rhino 7 and all the normal directions are correct. but it still does work for our client. I believe it is a closed model too. Could you check it for me or offer some further help?
In the past with more simple hull shapes we have made models that worked using Mesh to Nurbs to patch a steps model.
Ideally the model is generated in Modeler and then it will work. For hydrostatics NURBS or Mesh surfaces are required. And at any section they must form a closed section. The model you sent had over 20k IGES entities! MAXSURF is not designed to work with a model of that level of complexity. Reduce the model to the surfaces that define the outer watertight envelope of the hull only; delete all the curves since they are not used for hydrostatics. If the vessel is symmetrical then just define the surfaces on the starboard side.
your model seems to have many superimposed surfaces, everything appears to be in the model twice?
Thanks again. I think I sent the wrong model. Could you kindly take a look at this one?
Also if we model just one half what are the settings to choose in MaxSurf to communicate this?
Thanks so much for this.