2.7.1: Results Retrieval on Shells
Last updated
Last updated
The example file āSimpleShellESO.ghā (see fig. 2.7.1.1) contains two Python-scripts which will be explained below. The first script retrieves results from Karamba3Dās triangular shell elements:
Two python scripts: the first retrieves shell results (see code block below), the second one performs a simplified variant of an evolutionary structural optimization (ESO) procedure (see section 2.7.2).
Lines 3 and 4 reference the Karamba3D DotNet-assemblies. Depending on how you installed Rhino it might be necessary to adapt the paths. In case that one of them can not be located an error will be issued.
Plug the output of āoutā into a panel. If there is only one line of output, type āGrasshopperDeveloperSettingsā in the Rhino text window and check whether the āMemory load *.GHA assemblies using COFF byte arraysā-option is unhooked.
The retrieval of axial- and bending-energies works via the visitor-pattern (see [2] for details on that). Line 22 creates such a visitor object for the elastic element energies by handing over a reference to a C++ model, a state, a load-case index and possibly a load-case factor. Unless one performs non-linear calculations state ā0ā is the right one to chose.
A shell patch consists of several shell elements. This might lead to some confusion since in the Grasshopper UI shell patches are named āelementsā, in the C++ model however the patches consist of several triangular shell elements. In lines 26 and 27 the property āfe_indā returns the index of a C++ element that corresponds to a given C#-element. In case of shell-patches this corresponds to the first C++-element.
Other shell results like principal stresses can be retrieved directly from the FE-mesh like in lines 29 to 37.