Retiming a fire makes it disappear

Phoenix Issues
1

Hi,

I simulated a fire starting from a ‘burning fuel with smoke’ preset. For that purpose I followed this tutorial: Phoenix for 3ds Max

It works nicely.

But then I wanted to retime my fire as it was burning too fast for me. So I followed this tutorial: https://youtu.be/XdXb\_XX5W1Y?si=75XA\_8ybALV\_OX0D

Basically what I did was:

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then:

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And finally I ran the simulation again by clicking on the ‘Start Phoenix simulation’ button.

Surprisingly there is no viewport preview anymore (although ‘Show viewport preview’ is still enabled), and when I do a render my fire is gone.
I can see that new cache files have been calculated though.

Can you tell me what’s wrong?

Thanks a lot,

2

Hello,

In the simulation rollout, there is a Cache Content window. Can you verify that there are cache files being loaded, please? Most likely you are writing your retimed caches somewhere and the input file is not reading it back again. Try to locate it at set it as the new input when the resimulation is done and and you switch it off.

Cheers.

p.s. I’m talking about that window at the bottom.

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3

Hi,

Thanks.
I checked: I do have cache files loaded in this window but here is what I find inside:

[GRID: 198 800 cells, 71x80x35]

- Liquid/Temperature (300.00 : 300.00)

- Smoke (0.00 : 1.00)

- Velocity (0.04 : 1715.70)

[PARTICLES: 0 total]

- Particles of Fire_Faces: 0

* Simulated with Phoenix 5.20.00, Build ID: 20230706 for 3ds Max 2023 from Jul 6 2023
____________________________________________________________________________

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Whereas after the initial simulation I had this:

[GRID: 2 026 920 cells, 133x120x127]

- Liquid/Temperature (300.00 : 2000.00)

- Smoke (0.00 : 1.00)

- Velocity (0.08 : 1632.69)

[PARTICLES: 725 total]

- Particles of Fire_Faces: 725 (Position_phx, Velocity_phx, ID_phx)

* Simulated with Phoenix 5.20.00, Build ID: 20230706 for 3ds Max 2023 from Jul 6 2023
​____________________________________________________________________________

So it looks that for some reason no particules are emitted, plus the number of voxels is really low.

Anyway I found a workaround: I followed advice on this doc Phoenix for 3ds Max and was able to achieve a decent retiming, at least in low resolution it looks good so far.
I just set play back to 0.5 as I wanted and didn’t run any resimulation.

4

Hi,

Thank you for checking that out. In that case can you please send a simplified scene, it that is possible. So we can investigate.

You can use this link to submit the files here (at top right, there is a submit a request button)
https://support.chaos.com/hc/en-us