What is the difference between SECFORC and SPCFORC?

- November 11, 2024 at 12:35 pm
  
  renantequezonctu
  Subscriber
  
  I'm running a uniaxial tensile test simulation in LS-DYNA, using the LCSS data from a physical tensile test and MAT_089 material model. I'd like to capture the instantaneous force output to match the force measured by the load cell in the physical test.
  So far, I've tried the SECFORC and SPCFORC databases, but they produce similar force vs. time graphs. Could you advice which of these two databases - SECFORC or SPCFORC - better represents the force from the physical load cell? Or is there a more accurate method to obtain this output?
- November 12, 2024 at 6:27 am
  
  mohan.urs
  Ansys Employee
  
  Hey,
  The SECFORC outputs the forces at a cross section whereas SPCFORC outputs the forces which are associated with BOUNDARY_SPC command.
  Check out this FAQ which talks about various force analysis Force Analysis — Welcome to the LS-DYNA support site.
  Since this a is uniaxial tension test it should have one fixed support and a displacement or force at the other end so SPCFORC should do the trick. But i would suggest you to go through some literature to make the best choice since you have to match the values to that of the experimental.
  Regards,
  Mohan Urs