5 Replies Latest reply on May 15, 2012 10:39 PM by Shahrul 88

    Particle Study: Maximum Steps in Cell

    David Harrold

      I'm confused by one of the "Particle Fate" conditions I've run into: Maximum Steps in Cell.

       

      I've read: Help > SolidWorks Simulation > Flow Simulation Help Topics > Particle Study - Settings. According to the help entry, the available particle end conditions are Opening, Absorbed, Maximum Length, Maximum Time, and Maximum Iteration. All of these make sense to me. But when I run some models, I also get "Maximum Steps in Cell," which is not defined in the Help as far as I can tell.

       

      So does anyone know what Max Steps in Cell means?

        • Re: Particle Study: Maximum Steps in Cell
          David Harrold

          I have been looking into this a little further, but I seem to be getting more confused.

           

          I made a simple y-pipe and introduced particles in SW2011, SP0.0, as shown here: (cutaway view)

          y-pipe cutaway.jpg

           

           

          The particle fate is "Max Steps in Cell," but I couldn't find a Help entry that exaplains what this means. The particle path is visible when I zoom in:

          particle trace - max steps in cell.jpg

          The particle bounces off the pipe wall, then is pushed back into the wall and slides along it. Default Wall Condition is set to Reflection, e_n = 0.1, e_t = 0.1

           

          With the mesh shown, it's clear that the particle takes many steps in each cell:

          particle trace - max steps in cell - mesh.jpg

          The particle is  moving from the upper right corner to the lower left, and it's sliding along the pipe wall when it comes to a stop. I would expect the end condition to be "Absorbed" not "Max Steps in Cell" since the particle is on the wall, and it takes multiple steps in each preceeding cell. Also, according to the color, the particle was accelerating from about 90 m/s to 91 m/s when it suddenly reached the end of its path.

           

          Does anyone know what Max Steps in Cell means? Does it mean the particle bounced off a wall too many times in a cell? If so, how many times is too many?

          • Re: Particle Study: Maximum Steps in Cell
            Shahrul 88

            Hi All,

             

            I'm using solidworks to do convection heat transfer in the microcomputer. The problem is my understanding on the number of iterations.

             

            2 simulations are done through 2 different setting on the iteration:

                   1) goals convergence (result obtained as in Pic 1 attached - stop at iteration 56)

                   2) maximum iterations = 42 (result obtained as in Pic 2 attached - stop at iteration 42)

             

            How do I explain about the differences of data ( in this case temperature) at iteration 20 and iteration 30??

            For goals convergence; what is mean by goal convergence?? is it equilibrium state/ condition??

             

            This number of iterations are not explained about time, am I right?

             

            Thanks

             

            Pic 1.JPG

             

            Pic 2.JPG