A riser with CFD cell of 24x24x1632 cells was simulated and images was generated at the start of the simulation with Ascent. But as the CFD cell number increased to 80x80x5440, it doesn’t generate images anymore. The Ascent images for both cases are shown below. Any suggestions?
hard to diagnose without inputs
Unfortunately, this case can’t be shared within the forum as discussed during our user meeting. The case file can be shared within the public directory if needed.
@Yupeng - was this the problem that we worked around by making sure the slice filter (y=0) intersected all domains?
yes, you are correct.
Update: my initial explanation (slice filter lying on domain boundary) was incorrect.
The problem is simply that when there are many MPI ranks without data, the compositor was misbehaving. The fix is in Ascent, not Viskores. Tiled rendering overwrites valid pixels · Issue #1698 · Alpine-DAV/ascent · GitHub
You can build with Ascent git HEAD to pick up the fix, or wait until the next Ascent release which should include this fix. Ensuring that all the domains intersect the slice plane is a valid workaround.