4 Replies Latest reply on Oct 21, 2008 2:07 PM by John Scott

    Pressure Simulation Not Accurate

    John Scott
      I'm applying 17in of Hg to a face with the area of 771in^2.

      So I apply -8.35psi and the face displaces 1.418in. I know this face does not displace this extreme in the real world. So I double check by applying 6438psi to the face and it now displaces 0.0002in.

      Why the drastically different results? I'm pretty basic with FEA so please keep your answers basic.
        • Pressure Simulation Not Accurate
          Vince Adams
          Hi John, it could be a handful of things. Was there No Penetration contact? Were you accidentally looking at displacement in different areas? Did you accidentally change the units when you changed the loads?

          If none of these and if the only thing that changed was the pressure value (-8.35psi to 6438 psi), I'd need to see some images or the model to go further.

          -- Vince
            • Pressure Simulation Not Accurate
              John Scott
              It has to be something I'm doing...or not doing. I have attached images of the displacement plots below of the two scenarios.

              If this enough info Vince?
                • Pressure Simulation Not Accurate
                  John Scott
                  I just ran additional studies on small, medium & large doors. I can get the results to match up on large door only. Will recheck all my work???

                  Keeping all restraints, pressure, force (per size door) the same for all and using default settings. Maybe I will try copying mesh from pressure study to force study since model is the same.
                    • Pressure Simulation Not Accurate
                      John Scott
                      Okay, this thread can be ended. I got my results to match up, for reasons unknown. Just went back and re-did everything.

                      CosmosWorks may be more buggier than SW. I'm noticing strange things like...when using configuration to perform design variations CW goes back and converts all previous studies from pressure to force. I have gone back redone this and created a new config and CW again goes back and converts all previous studies to force...?

                      Definitely cannot rely on this CW and its results other than to use it as a BASIC design tool providing BASIC design direction.