3 Replies Latest reply on Mar 5, 2013 9:20 PM by Joe Galliera

    Need help setting up a flow simulation

    Mark Cifuentes
    Mark Cifuentes Mar 2, 2013 6:10 PM

      Hello, I just started to learn solidworks flow simulation a few days ago and i've been testing some airfoils. Is there a way to make a simulation like the one in the video below? Where the airfoil gradually increases in the angle of attack?

       

      http://www.youtube.com/watch?v=Ti5zUD08w5s

       

      Thanks

        • Re: Need help setting up a flow simulation
          Joe Galliera
          Joe Galliera Employee Mar 3, 2013 9:56 PM (in response to Mark Cifuentes)

          No, this requires a moving mesh capability that Flow Sim does not current support.

           

          But you can do something similar by running successive FS projects using AoA as the changing parameter.  Simply set up an Angle mate in an Assembly, and drive the changes using this mate.

           

          See sample project for a NACA 0015 airfoil, by clicking here.  Zipped SW Assembly with associated Flow SIm projects set up, which I believe is last saved in SW 2012.

           

          Includes various angles of attack for several Reynold's numbers.

            • Re: Need help setting up a flow simulation
              Jared Conway
              Jared Conway Mar 5, 2013 3:46 PM (in response to Joe Galliera)

              Joe, I think that is the best way to go. That way if you need to turn on transient to look at vortex shedding..etc, it is just matter of flipping a switch. To add to what Joe suggested, the new parametric sweep study in 2013 would make short work of getting that setup.

               

              The only other thing I thought about was creating a velocity dependancy in the inital conditions and using transient analysis. You wouldn't be rotating the wing, you'd be rotating the incoming velocity. I've attached an example of this. In practical application I'd suggest more time between angles of attack and automatic time stepping.

                • Re: Need help setting up a flow simulation
                  Joe Galliera
                  Joe Galliera Employee Mar 5, 2013 9:20 PM (in response to Jared Conway)

                  Three things you need to be conscience of when approaching this transient effect by changing the velocity vector over time are:

                   

                  1) the Computational Domain needs to be able to accomodate all directions that the flow is moving, i.e. both sides behind the trailing edge and above the upper chord would have to be extended;

                   

                  2) when the airflow moves at an skewed angle to the cell faces, you will need more cells to get the same accuracy as when the flow is normal to the cell faces;

                   

                  3) see my referenced post in terms of time step for a transient analysis, and where the time step is sensitive to changing velocity and cell size, because the wall clock time to solve this time dependent problem can be significant.