6 Replies Latest reply on Feb 20, 2014 12:51 AM by Jared Conway

    How to judge the result of analysis

    Feizc Zc

      I am the beginner in the study of solidworks simulation. I just wonder that although I did followe all the steps in accordance with the tutorial, the result of my own analysis were almost all different from the tutorials`.   Some of them are slightly different (around 1-3%), but there are some analysis reults were even reach to about 15% bigger than the tutorial. Some of them can be explained for the difference from meshing size. However, it doesn`t explained the results difference that happened between the examples exactly same. Does the version difference makes the analysis result difference?

        • Re: How to judge the result of analysis
          Jared Conway

          Version and sp may have some influence on the general values. However you can't blindly look at mins and maxes only. My guess is overall the values are very close. It could also be the use of solver, slight changes in models...etc. I wouldn't focus on the absolutes and rather that you are within reason.

          • Re: How to judge the result of analysis
            J. Mather

            Feizc Zc wrote:

             

            .... but there are some analysis reults were even reach to about 15% bigger than the tutorial. ...

            Can you attach file here?

              • Re: How to judge the result of analysis
                Feizc Zc

                The following link is an example I posted on here weeks ago.

                It include the detailed operation steps and the model file.

                 

                https://forum.solidworks.com/message/410043#410043

                  • Re: How to judge the result of analysis
                    Jared Conway

                    where is the 15% discrepency?

                     

                    is this something you can work with yoru reseller on?

                      • Re: How to judge the result of analysis
                        Feizc Zc

                        I learn solidworks by myself. I don`t have any after sell service from reseller.

                         

                        The 15% discrepency happened on an case study I finished 2days ago. I don`t mean I am querying the accuracy and functionality of  solidworks simulation. Just want to know how to find the reason that why my calculation results were often different from the tutorials`

                         

                        The case is that conduct a one degree distortion along axial dirction on a spot welding tube, the calculated twisting force from tutorial was 8584.9N.m.   My own analysis result shows the twisting force was around 10,000N.m

                          • Re: How to judge the result of analysis
                            Jared Conway

                            in your original post you state that there is up to 15% discrepancy in a tutorial example, it sounds like the problem is with a case that you've tried yourself and that the tutorials are matching quite well (1-3%). that is a good first step. now we understand you're comparing simulation with a hand calculation or with physical results.

                             

                            Let's start with what you're using as your measuing stick. What equation are you using? What inputs? What assumptions does the equation make etc....

                             

                            Here's an example. Had a customer that was doing a beam deflection problem. Simulation and hand calcs weren't matching. Checked the equation he was using and his equation was only good for slender beams that were much longer than they were thick. Once the correct equation was used, the values were very close to simulation. Considering simulation doesn't make any assumptions, it was accepted as the "correct" value and when tested physically came out very close.