Quick smoke vorticity is broken. #80877

New Issue

Anna · 2020-09-17T11:51:21+02:00

Anna commented

2020-09-17 11:51:21 +02:00

System Information
Operating system: Windows 10.
Graphics card: NVIDIA GeForce RTX 2080 Super

Blender Version
Broken: (version: 2.90.0, branch: master, commit date: 2020-08-31 11:26, hash: 0330d1af29, type: Release
The same is on experimental 2.91
system-info.txt

Worked: (newest version of Blender that worked as expected)
I'm not sure, but in video tutorial of Blender 2.7 is working correctly. Link to vid: https://www.youtube.com/watch?v=BhjK-6t9Gqs&t=2m10s

Short description of error
When you add vorticity to smoke sim it does something crazy,video with 0 vorticity:
smoke_novorticity.wmv

With vorticity value of 3 here is what happens:
smoke_vorticity.wmv
It happens a bit differently on different strength but once you add any vorticity it goes wrongly.

Exact steps for others to reproduce the error
The file is simple - adding icosphere, make couple keyframes to animate it. Add quick smoke, adjust domain. For emitter make temp.diff -1, enable initial velocity. For smoke domain set vorticity to 3.
smoke_voticity.blend

**System Information** Operating system: Windows 10. Graphics card: NVIDIA GeForce RTX 2080 Super **Blender Version** Broken: (version: 2.90.0, branch: master, commit date: 2020-08-31 11:26, hash: 0330d1af29c0, type: Release The same is on experimental 2.91 [system-info.txt](https://archive.blender.org/developer/F8891830/system-info.txt) Worked: (newest version of Blender that worked as expected) I'm not sure, but in video tutorial of Blender 2.7 is working correctly. Link to vid: https://www.youtube.com/watch?v=BhjK-6t9Gqs&t=2m10s **Short description of error** When you add vorticity to smoke sim it does something crazy,video with 0 vorticity: [smoke_novorticity.wmv](https://archive.blender.org/developer/F8891832/smoke_novorticity.wmv) With vorticity value of 3 here is what happens: [smoke_vorticity.wmv](https://archive.blender.org/developer/F8891833/smoke_vorticity.wmv) It happens a bit differently on different strength but once you add any vorticity it goes wrongly. **Exact steps for others to reproduce the error** The file is simple - adding icosphere, make couple keyframes to animate it. Add quick smoke, adjust domain. For emitter make temp.diff -1, enable initial velocity. For smoke domain set vorticity to 3. [smoke_voticity.blend](https://archive.blender.org/developer/F8891839/smoke_voticity.blend)

Anna commented

2020-09-17 11:51:21 +02:00

Added subscriber: @devox

blender-admin commented

2020-09-17 11:51:21 +02:00

#96208 was marked as duplicate of this issue

Germano Cavalcante commented

2020-09-18 20:39:51 +02:00

Added subscribers: @sebbas, @mano-wii

Germano Cavalcante commented

2020-09-18 20:39:51 +02:00

2.7 had another fluid simulation system.
blender 2.7 tutorials no longer apply with 2.8's new fluid system.

Maybe now 3.0 is a high value for turbulence.
I don't think this is a bug.
@sebbas, what do you think?

2.7 had another fluid simulation system. blender 2.7 tutorials no longer apply with 2.8's new fluid system. Maybe now 3.0 is a high value for turbulence. I don't think this is a bug. @sebbas, what do you think?

Anna commented

2020-09-24 14:47:08 +02:00

Even with lower value, 0.07 for example, it starts ok, but if simulation is longer especially with turbulence field on it does that volume noise closer to the end. I'm not sure if this is an expected behavior.