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Defining Ansys Superelement SUB File Manually

Photo by  James Owen  on  Unsplash A surprisingly popular blog-post written here is Exporting Stiffness Matrix from Ansys . A sensible follow up question is what can one do with the exported stiffness matrix? In a recent Xansys Forum post, a question was raised on how we can edit the stiffness matrix of a superelement and use it for our model.  An approach presented below is to first create a superelement that has the same number of DOF and nodal location that will serve as a template. An APDL script can then be written to edit the stiffness matrix entries as desired before exporting to a new superelement *.SUB file for use in future models. The self-contained script below demonstrates this.  /prep7 et ,1, 185 mp , ex, 1, 200e3 mp , prxy, 1, 0.33 w = 0.1 ! single element (note nodal locations) n , 1, w, -w, -w n , 2, w, w, -w n , 3, -w, w, -w n , 4, -w, -w, -w n , 5, w, -w, w n , 6, w, w, w n , 7, -w, w, w n , 8, -w, -w, w e , 1, 2, 3, 4, 5, 6, 7, 8 /solu antype , substr     ! analy

CMS circa Ansys 2019 R3

CMS circa 2019R3 Roughly a year ago, I wrote about how you could reuse CMS elements using APDL snippets within Ansys Mechanical. The new feature of Condensed Geometry in recent releases unfortunately does not completely solve the problem; but does get you half way there. To recap, the goal here is to have a part (A) that is complicated/ huge  but now condensed into a teeny-tiny Super-Element. Changes can be quickly made to other parts (B). When combined together (C/D), the model as a whole is smaller and faster to solve since A is reused. This blog post is an update to the earlier post that uses the same technique but takes advantage of two new tools:  Condensed Geometry & Mesh Numbering . To get started, download the Ansys 2019R3 archived file to follow along. Archived File with RST ( 177.0MB )    Link  or Archived File without RST ( 1.5MB )   Link The rough procedure: Create and mesh both Analysis A for CMS part and Analysis B for other parts.  Note down maximum