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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

Advice for Enterprising Engineers

This post fits squarely in "other thoughts" category. Some engineers asked for my advice on advancing their careers. To avoid giving bland advice, I hope these strategic framework might help guide their decisions. Be a Hero What does it mean to "Be a Hero"? It means you have to achieve something many people in the company will say is significant. It could be improving a tedious process, solving a customer issue that's been a pain in the rear for too long or introduce a tool that solves an unsolvable problem in the past. Let's call these " Hero Problems ". To be a hero, you will have to first develop an understanding of what the company needs. All companies will have their share of problems. Ask around, pay attention when coworkers say phrases like "I wish we could..." or "this is ridiculous, we should...". These offer clues on real Hero Problems. But why? Why should this be a strategy? This is the " Demand "

Matrix Transfer between MATLAB and Ansys

Matrix Transfer * Reading and writing matrix or arrays to MATLAB and back can be painstaking as described by SimuTech in a well written article  using *TREAD  or *VREAD . Wouldn't it be great to have someone else do the heavy lifting for you on formatting etc? Fortunately there is a Matrix Market format sponsored by NIST that is also supported by Ansys and Matlab. There are two very useful MATLAB functions created just for this purpose: mmread.m   for reading in the Market Matrix file into MATLAB mmwrite.m for writing the matrix into a Matrix Market file Writing Matrix or Arrays from Ansys to be Read by MATLAB In Ansys... /prep7 *dim , c,, 10,10, 1 ! Example Matrix enow = 0 *do , ct, 1, 10              *do , ct2, 1, 10         c(ct,ct2) = ct*ct2     *enddo     *enddo     !!! Writes out Matrix to matlab *dmat , exportmatrix, D, import, APDL, c ! export to matrix file *export , exportmatrix, mmf, mytemp.mtx In MATLAB, the command is simply... c = mmrea