Why is the section plane moving in visualization mode (Post) ?

AbrilP
AbrilP Altair Community Member

I have an issue related to the visualization of a CFD analysis. When I put a section plane and animate it, it moves, instead of showing the movement "inside" of it. Such as the current movement as the time passes. Before, when I was studying an individual piece it would let me, but now I have this big cluster of pieces and it does this weird thing. I don't know how to return to the other type of visualization or if it's something I gotta change in some parameter. I tried to put it on Transient, instead of Steady, with a 5 second total time.

Best Answer

  • acupro
    acupro
    Altair Employee
    Answer ✓

    By default the results/variables are output every 100 time steps. With the settings from that image, you're running maybe 11 time steps - so you'll only get one output set. Thus - animating will not advance time steps, as there will be only one time step available. If you go into Solution > Output/Fields - you can indicate to output every time step (Time Step Interval = 1) to get more output sets available in Post. Then animating should then animate the changing results on the slice, since there are multiple output sets, rather than moving/animating the slice itself.

Answers

  • acupro
    acupro
    Altair Employee

    Is this a steady-state simulation - or a transient simulation? Is there just a single time step available in post-processing? If you intended to have a transient run, with multiple output steps, make sure you set that properly in the simulation setup - Solution > Output/Fields and adjust the Time Step Interval (or Time Interval) for Solution Variables.

  • AbrilP
    AbrilP Altair Community Member

    The one from the video is a Transient simulation with the parameters from the picture. But in reality it is a Steady simulation because there are no changes in the flow. It is always the same velocity hitting the figures that are underwater. In the past putting it on transient allowed me to see an animation of the flow hitting the structure and seeing how the current was created, when I did it with streamlines and with a section plane. But now it doesn't matter in which state (Steady or Transient) I process that the visualization plane acts the same way, moving itself one side to another. I don't know if it's related to the time marching stat, maybe it's some other parameter.

    Maybe I am confused with the concepts, I am just a beginner. But yeah, what I need to see is this kind of visualization shown in the video (it's a bit bugged due to other factors):

  • acupro
    acupro
    Altair Employee
    Answer ✓

    By default the results/variables are output every 100 time steps. With the settings from that image, you're running maybe 11 time steps - so you'll only get one output set. Thus - animating will not advance time steps, as there will be only one time step available. If you go into Solution > Output/Fields - you can indicate to output every time step (Time Step Interval = 1) to get more output sets available in Post. Then animating should then animate the changing results on the slice, since there are multiple output sets, rather than moving/animating the slice itself.