Matrix27 in harmonic analysis workbench

- March 15, 2024 at 9:52 am
  
  Purinut Lersnimitthum
  Subscriber
  
  I tried to use matrix27 as spring element and I changed the spring joint in workbench to Matrix27 by the code below (element type 4 is spring joint element)
  /PREP7
  et,200,MATRIX27
  KEYOPT,200,2,2
  KEYOPT,200,3,4
  KEYOPT,200,4,1
  R,200,34411799,136089343,0,0,0,0,
  RMORE,-34411799,-136089343,0,0,0,0,
  RMORE,232106005,424813159,0,0,0,0,
  RMORE,-232106005,-424813159,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  RMORE,-34411799,-136089343,0,0,0,0,
  RMORE,34411799,136089343,0,0,0,0,
  RMORE,-232106005,-424813159,0,0,0,0,
  RMORE,232106005,424813159,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  RMORE,0,0,0,0,0,0,
  esel,s,type,,4
  emodif,all,type,200
  ALLSEL
  /SOLU
  This is simple spring and mass system. The point mass attached to small 2D plane strain area at which the MATRIX27 also connected and MATRIX27 connected to 2D plane strain square area where it was subjected to displacement excitation.
  and the result of harmonic response is zero for the entire range of the frequency for both the x and y direction. I would like to know how to fix this.
  
  Thanks.
- March 18, 2024 at 3:46 pm
  
  Chandra Sekaran
  Ansys Employee
  
  I did not check your R definitions but one thing I noticed is you are changing the TYPE to 200 with emodif command. But you also need change the real ID to 200, don't you? Like 'emodif,all,real,200' for the matrix27 properties to take effect.
  '?
  - March 18, 2024 at 7:03 pm
    
    Purinut Lersnimitthum
    Subscriber
    
    Many thanks, the problem is solved????.