Maniphest T96208

Fluid sim (smoke/fire) has issues with multiple objects in one domain
Closed, Duplicate
Actions

Assigned To
None
Authored By
Robert Nederhorst (rnederhorst)
Mar 7 2022, 12:12 AM
Tags
  • BF Blender
Subscribers
Ethan Hall (Ethan1080)
Omar Emara (OmarSquircleArt)
Robert Nederhorst (rnederhorst)

Description

System Information
Operating system: Win 11
Graphics card: RTX6000

Blender Version
Broken: 3.1.0 RC (March 03)
Worked: N/A

The simulation goes haywire after frame 230. This appears to be an issue with multiple fluid (inflow) objects entering the same fluid domain

Exact steps for others to reproduce the error
see attached blend file. SIm happens very quickly.
After frame 230 the problem will start to become very apparent.

fluid-sim-bug.blend846 KBDownload

Event Timeline

Robert Nederhorst (rnederhorst) created this task.Mar 7 2022, 12:12 AM
Omar Emara (OmarSquircleArt) changed the task status from Needs Triage to Needs Information from User.Mar 7 2022, 8:46 AM
Omar Emara (OmarSquircleArt) added a subscriber: Omar Emara (OmarSquircleArt).

I can confirm the issue. But can you try to narrow down its cause as much as possible. For instance, I disabled Dissolve and Noise and the issue still happened, so they are not the case.
Steps to recreate it from the default settings would be good.

Ethan Hall (Ethan1080) added a subscriber: Ethan Hall (Ethan1080).Mar 8 2022, 2:25 AM

Turn off Use Adaptive Time Steps in the domain object's physics settings. That seems to make the simulation more tame.

Robert Nederhorst (rnederhorst) added a comment.Mar 8 2022, 5:40 PM

Thanks to you both for this. I am trying to really narrow the issue down.

Omar Emara (OmarSquircleArt) added a comment.Jun 7 2022, 1:10 PM

Did you manage to narrow this issue down?

Robert Nederhorst (rnederhorst) added a comment.Jun 7 2022, 1:59 PM

I couldn't reliably do this unfortunately. I did try but it was a bit cagey and the adaptive time step was a bit better. I then adjusted animations, etc and it sorted it out for the most part. Apologies for any wasted time on this.

Omar Emara (OmarSquircleArt) added a comment.Jun 7 2022, 2:04 PM

That's okay. I will try to do that myself.

Omar Emara (OmarSquircleArt) closed this task as a duplicate of T80877: Quick smoke vorticity is broken..Jun 7 2022, 3:05 PM

I narrowed it down to the vorticity of the gas, so merging to that report.