Wall boundary condition in AcuTrace

K. Yamamoto
K. Yamamoto Altair Community Member
edited October 17 in Community Q&A

Hi, experts.

In the analysis results (animation) by acutrace of the tutorial ACU-T: 6000 Static mixer, the particles do not appear to be reflected by the wall set as the reflecting wall. Even in my own model (analysis of particle behavior in a tank filled with water in a single-phase flow), reflection does not occur on the wall set as the reflecting wall (restitution coefficient is the default value of 1.0) in the animation, and the particles disappear when they reach the reflecting wall. The final coordinates of the particles output in end.file were also coordinates on the wall surface.

Also, the outlet of the ACU-T: 6000 static mixer is set to the stopping wall, but the particles that reach the outlet appear to disappear from the animation. This does not seem to be different in nature from the terminating wall.
In acutrace, do particles that reach the wall disappear regardless of whether the wall is set to reflecting, stopping, or terminating?

In my model (analysis of particle behavior in a tank filled with water in a single-phase flow), low-density particles (0.9 g/cm3) rise due to buoyancy and disappear after reaching the wall at the top of the tank (reflecting wall). And high-density particles (1.6g/cm3) sink due to gravity and also disappear after reaching the bottom of the tank (reflecting wall).
Could you please explain why particles are not reflected by the reflecting wall and disappear?

Thank you.

Tagged:

Answers

  • acupro
    acupro
    Altair Employee
    edited October 17

    According to the documentation, Simple BC type = wall and type = slip should both translate to the default reflecting wall behavior in AcuTrace.  (In the tutorial, the outlet Simple BC type = outflow would not have the same default treatment, and the particles should leave the domain.)

    I've tested a simple model in 2024.1, and the particles with the default settings resulting in AcuTrace reflecting wall and COR 1.0 get 'captured' by those boundaries, remain visible, and can move along those boundaries.  However I really don't see the expected 'bounce' with COR 1.0 - so there's still likely some sort of deficiency in AcuTrace.

    Do you have access to the latest release - 2024.1 - for testing on your model?

Categories