1
$\begingroup$

Summary

I created a basic rocket thruster via two planar inflows (smoke and flame) housed inside of a non-planar cylinder/cone effector (set to collision). The animation is fine with a smaller domain. When I increase the domain size, the smoke and flame clip through the effector without adjusting any other settings. I have applied scale and set origin to center of mass with each object. I would like to know why this is and how it can be avoided

The issue in detail

I am doing some fluid and domain practice to eventually be able to create a nice rocket animation. I created a rough mock up of a thruster exhaust which involves:

  • Two planar circles set to inflow (one for smoke, one for flame)
  • One non- planar effector (set to Collision, Surface Thickness 0.1)
  • One cubical domain

enter image description here

enter image description here

I have no issues with the animation when I bake it with a domain of this size: ~25 m (X) 25 m (Y) 37 m (z)

The problem arises when I scale the domain bigger 3x ( X and Y to 75 m). The smoke and flame start to "seep" through the effector from 4 different points as a result.

enter image description here enter image description here

I have played around with the surface emission of the inflows as well as the surface thickness of the effector and have been able to mitigate this issue some as a result but it completely changes how the flame and smoke look as a result, thereby ruining the intended look.

My hope is that someone could explain to me why and how this occurs as I am perplexed as to how the domain size would effect the inflows. My preconceived understanding was that the domain was simply a force-field of sorts that just prevented the fluids from reaching past a certain area but it would seem it has direct effects on the physics before it's boundaries have even played a role.

Further discoveries

Firstly, I set the domain to have border collisions at bottom (careless mistake but didn't seem to be the cause of my main issue). I also made the walls of the 3D effector much larger which did indeed fix the problem:

enter image description here

I encountered a new problem, however, once I set it all to adaptive domain. This caused the fluids to violently clip through the top of the effector until the domain box expanded larger.

enter image description here

I am a bit stumped as to how to fix this issue as it seems trying to accommodate values and thickness for an adaptive domain is a much more complicated issue.

$\endgroup$
2
  • $\begingroup$ Please share your blend file blend-exchange.com $\endgroup$
    – vklidu
    Feb 5 at 5:01
  • $\begingroup$ Please edit your question to focus at one issue per post. Frame 1-7 image is probably just an issue of scaling domain without increasing domain divisions or what you see is baked result or old cached data. On other hand your edit seems to be an issue based on a different inputs. Thanks to keep it organised so we can better understand to your issue. $\endgroup$
    – vklidu
    Feb 5 at 5:26

1 Answer 1

0
$\begingroup$

I played around with the margin in the adaptive domain settings and found that setting it to 8 resolved the issues of it clipping. I believe I have now found the solution to my own problem, but I am certainly up to having some extra feedback on this issue or perhaps other (better?) ways to go about solving it.

enter image description here

enter image description here

$\endgroup$

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .