Why is this fire turned on and off?

Hi all, I hope you’re doing great :slight_smile:

I attached my rendered video where you can see the fire being turned on and off. I don’t care if the fire is too large or long. I’m concerned about the fire being turned off at certain times.

I think this issue is not related to the animation of the matchstick. After this animation, the matchstick stands still or stops moving but the fire continues to be turned on and off.

I tried every single setting. My trial and error took days but it didn’t succeed. What could be the reason?

I’m using blender 2.80 EEVEE (Old smoke simulation / not mantaflow).

Here are the settings at which I rendered the attached video:

a1995-2062.mkv (132.8 KB)

You have to increase Sampling Subframes.

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This crashes blender while baking. Even if the subframes value = 1. So, I run into another problem :slight_smile: Do you have any tips?
Thank you for giving me the solution,

I just realized that you had a pretty big resolution with adaptive domain.
Crash is probably due to a lack of memory or a bug in 2.80 with adaptive domain.
I don’t remember how stable was smoke in 2.80. I am not sure it was as stable as in 2.79.

So, to reduce memory :
Try to reduce resolution, to transfer a little of wanted simulation cells to Adaptive domain or to High Resolution and to animate domain to make it follow match movement a little bit.

And check if it is not related to a bug, by disabling adaptive domain.

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Hi Zeauro :smile:
Thank you very very VERY much for the useful answer. My domain was too large because the matchstick moves in a large area (some other animations not shown in the video). The fire looked square (something like a pixelated image). That’s why I had to increase the resolution of the domain. Now, your idea is great which is to animate a small domain instead of having a large fixed one. I wish you a happy day. God bless you and your family. Good luck,