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How to implement 8 cores rather than 1 (LS-Dyna Solver)

    • MohammadMahdi

      Hi. We recently bought "Ansys Ls-Dyna HPC 8 cores" but do not know how to change our previous 1-core analysis (SMP-single precision) into HPC 8-core analysis. Before, I used to run my .k files with APDL>LS-DYNA solver with no HPC. How about now?

      1. To increase the No. of processors from 1 to 8, should I change anything in my original .k file?
      2. Should I use another solver than what I already used? I used to run my k files with SMP-single precision?
      3. Please take a look at the picture below, that is what I tried. Is that what I am supposed to do?

      Thank you in advance for your valuable help.

    • MohammadMahdi
      The problem was related to the server definition. Now, it's fixed and I'm able to run my .k files using DMP without changing anything in my original .k file.
      However, the results I get from HPC-DMP-Intel MPI(8 cores) are different from when I use SMP-single precision (1 core). I changed nothing in my .k file. Please let me know which one I can trust? SMP-one core or HPC-8 core?
    • Reno Genest
      Ansys Employee

      When you run HPC-DMP, you are using the MPP version of the LS-DYNA solver and you will get slightly different results with different number of cores. For example, the same model run with MPP 1 core will be give slightly different results than with 2 cores, or 4 cores, or 6 cores, etc.
      You could run with SMP 8 cores and consistency checking and get the same results as with 1 SMP core. I recommend you try it:

      How much is the difference (in percentage) between MPP 8 cores and SMP 1 core?


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