ansys

extracting mass and stiffness matrices from ANSYS

I am trying to extract both mass and stiffness sparse matrices from modal analysis using ANSYS 15 software, i used next code :

  !Stiffness
  *SMAT, MatKS, D, import, full, file.full, stiff
  *SMAT, Nod2Bcs, D, import, full, file.full,NOD2BCS
  *print, MatK, matKS.txt 
  *export, MatKS, mmf, matKSMMF.txt 
  !Mass
  *SMAT, MatMS, D, import, full, file.full, MASS
  *SMAT, Nod2Bcs, D, import, full, file.full,NOD2BCS
  *print, MatMS, matMS.txt 
  *export, MatMS, mmf, matMSMMF.txt

I received 2 files in MMF format, one for the mass(matMsmmf.txt) and the other for stiffness (matKSMMF.txt). When I try to apply upper commands for ANSYS 19 or ANSYS 21 i receive next error arise:

*SMA command fails to open the file  file.full

I need some code to overcome this problem or the name of the file that contains required data rather than file.full

Solution

  • Finally, I used the next APDL code with ANSYS Workbench 22R1 and it worked :

    /AUX2 
COMBINE,FULL ! Combine .FULL files
/POST1
*SMAT,MatKS,D,IMPORT,FULL,file.full,STIFF
*SMAT,MatMS,D,IMPORT,FULL,file.full,MASS
*export,MatKS,mmf,matK_MMF.txt
*export,MatMS,mmf,matM_MMF.txt

    It worked pretty well and gave me neat files in mmf format