8 Replies Latest reply on Aug 4, 2014 11:44 PM by Jared Conway

    a sharing violation occured while accessing an unnamed file- and other simulation issues

    John Rhodes

      I'm a previous ANSYS user (from a while ago) and I'm going to be using solidworks simulation in my next job. 

       

      I'm really disappointed in the quality of the simulation software.  I've got installed on three different computers (multiple times on each computer to make sure it's installed right), and I've had nothing but issues with simulation.  This is a total opposite of the the modeling environment, which is works very nicely.

       

      Everything was going well, when suddenly, my simulation wouldn't run.  After meshing, it gave the error "Midside nodes on two edges of an element are merged, element: (reducing mesh tolerance or specifying a higher no. of points for Jacobian check for meshing may help)". 

       

      So, I messed around with the mesh settings.  No luck.  I removed most of model to see if I could still run any simulation, when I got the error message "A Sharing violation occured while accessing an unnamed file".  Then, it stopped solving, but the solver window didn't close, so I couldn't do anything else.  When I closed SW, the solver window stayed open, but I couldn't close it without going to task manager and ending it.

       

      Right there, there were three bugs, the error message that is only meaningful to the SW programming team, the fact that solving can end without closing the window which leaves solidworks in a state that it needs to be restarted, the solving window does not close when SW closes, and the solving window can enter a state where it cannot be closed without going to task manager.

       

      My questions are: why do the two errors occur, how do I fix them, and should I just use ANSYS 2007 instead?  I'm doing very basic simulation, but I have no desire to waste hours of my life fighting crap software.

        • Re: a sharing violation occured while accessing an unnamed file- and other simulation issues
          Jerry Steiger

          John,

           

          I am an ANSYS user who has much less experience with SolidWorks Simulation. The few times that I or my colleagues have used SolidWorks Simulation it has worked well. These have usually been relatively straightforward; when we have more difficult analyses to run it usually falls on me to do it and I do it in ANSYS. That is partially because I am more familiar with ANSYS and partially because I am a bit leary of using SW Sim on the tough stuff. The other guys use SW Sim because it's easy to use, unlike ANSYS. Since you are used to lrunning ANSYS, this probably isn't much of an issue, although I always struggle after not using it for a few months.

           

          From following this forum, it seems to me that SW Sim IS more buggy than ANSYS. On the other hand, a lot of people are getting acceptable results and you say that your simulations are pretty basic, so I wouldn't expect you to have many problems.

           

          In a couple of cases we have run either the same or a very similar analyses in SW Sim and ANSYS and SW Sim was substantially faster. None of the analyses took more than a few minutes to run, so the faster solution time didn't really matter to us.

           

          Meshing does seem to be one of SW Sim's weaknesses. We originally chose ANSYS over the competition, which included COSMOS, the predecessor of SW Sim, because the fellow who did the evaluation thought that ANSYS had the best mesher. (On the other hand, he was most familiar with ANSYS, having used it in school.) The other guys have run into a few cases where they had difficulty meshing parts, but they always managed to work their way around it.

           

          I would worry about what operating system you will need to run such old code.

           

          Jerry S.

            • Re: a sharing violation occured while accessing an unnamed file- and other simulation issues
              John Rhodes

              Thanks.  I still have the old ANSYS machine, so we'll just be using that.

               

              I've had some better luck using very low quality meshes in SW, and I bet I could figure it out if I had enough time, but I know ANSYS very well, and as you said, the mesher is much superior.

              • Re: a sharing violation occured while accessing an unnamed file- and other simulation issues
                Jared Conway

                I haven't used ansys so I can't speak from experience.

                 

                But regarding the mesher, I don't know if I'd say it is a weakness. It can mesh almost anything, it just doesn't have some options tha people want like adding noding a model manually or other elements. But is that important if it has a good GUI, meshes and solves quickly and gives accurate results?

                 

                Regarding buggyness, inherently when you make something more user friendly you also expose it to use by a wider variety of people with a wide skillset. I think a lot of buggyness you see is from people using it with little experience. This makes it look buggy when in fact it is generally user related. With ansys you generally have trained analysts, they have one way to do it, they do it the same way, very easy to test and document that which I think sometimes makes it look less buggy. But again, generally buggy ness is ui related, results are still accurate.

                 

                And regarding running harder problems in ansys. If solidworks simulation had the same physics represented, I would think they are comparable. If you need other physics or a specific solver, sure , take it to another tool. For example super nonlinear with contact, I might take to abaqus

              • Re: a sharing violation occured while accessing an unnamed file- and other simulation issues
                Jared Conway

                Use simulation every day basically and support many customers with simulation and have seen those errors probably 10 times in  10 years. Both well documented in the swx kb. Both generally related to feeding bad geometry into the mesher. Sometimes a bad results location like Dropbox or something. Any chance you are attacking this without getting some guidance from your car on best practices? I'd guess the same ones from ansys would apply so I'd be curious how you'd imposed and checked your geometry before starting the analysis. I'd guess it isn't that the mesher in ansys is better, I'd guess that from your experience you inherently plan around its limitations based on your experience.

                • Re: a sharing violation occured while accessing an unnamed file- and other simulation issues
                  Alessandro Tornincasa

                  Midside nodes on two edges of an element are merged, element: (reducing mesh tolerance or specifying a higher no. of points for Jacobian check for meshing may help)".

                   

                  I've seen this error occuring only with a couple of customers:

                  - in one case one customer wasn't aware he was meshing his assembly with incompatibile mesh. Mesh was failing all the time, therefore he activated an option in the mesh called "incompatibile mesh for failed parts". Mesh was bad quality and the solver also was having a hard time using constraint equations to bond parts

                  - in another case customer had an assembly with thin parts but they didn't have uniform thickness, therefore he couldn't use shell elements. His mesh had very bad quality with very high aspect ratio elements. Reducing mesh size in order to have elements with aspect ratio no more than 10 solved the issue.

                   

                  Generally speaking ansys mesher is much more powerful than solidworks simulation. The other Dassault Systèmes tool that can compare to that capability is SIMULIA ABAQUS.

                  SolidWorks Simulation on the other hand is easy to use, and has an unmatched level of integration, and a much lower cost than high end tools.

                   

                  Unless you're trying to mesh a very complicated assembly (like a car engine, I'm sure you'll be able to carry out your analysis.

                   

                  By the way, I've seen solidworks simulation meshing a car engine with the curvature based mesher. All you need is enough Ram to account for the small elements generated by the small curvature regions.

                   

                  Alex