Expand Vel Field ( don't want use divergence )

[Ultraman]

Hey Guys .

I want to Ask how can Expand my Velocity Field without using any divergence  (my vel coming from sop source ) .
maybe below picture tell more , what i'm talking ..

Thanks as Always 

 

Edited May 12, 2020 by Milad Savar
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[anim]

if you are talking about smoke/pyro solver, then the only way to have true expansion is using divergence, since the main point of fluid sim is that it's nondivergent so that you either provide goal divergence that will allow it to expand or contract or avoid pressure projection altogether and therefore lose fluid motion

 

[Ultraman]

1 hour ago, anim said:

if you are talking about smoke/pyro solver, then the only way to have true expansion is using divergence, since the main point of fluid sim is that it's nondivergent so that you either provide goal divergence that will allow it to expand or contract or avoid pressure projection altogether and therefore lose fluid motion

 

thanks for quick response Tomas  .

there is hip file .. and  i'm taking about pyro  stuff 
i know true expand is divergence but i need only expand vel field to more cover my density around  ( it's possible in sop , but i wanna know how can do it in DOP )
 

Example.hip

[k2p8]

You may try to tweak the gasresizefluiddynamic. If you dive in, you ll find a sopsolver with ResizeBounds data. Inside merge a bound of your velfield from sop with the out node (don't forget to tag the merge node as display).

It some sort of a minimum of the 2 bounds so your sim will expand of the vel field at the next frame.

[Ultraman]

1 hour ago, k2p8 said:

You may try to tweak the gasresizefluiddynamic. If you dive in, you ll find a sopsolver with ResizeBounds data. Inside merge a bound of your velfield from sop with the out node (don't forget to tag the merge node as display).

It some sort of a minimum of the 2 bounds so your sim will expand of the vel field at the next frame.

thanks ,  i'm not talk about resize container ,  if is it your means . ( i know my question is little dump ,  sorry about that ) ..

i'm speak about expand vortex vel , which coming from sop source 

Edited May 12, 2020 by Milad Savar

[toadstorm]

I have a DOP solution for you, but to be honest you might just want to make your vortex bigger in SOPs rather than handle it in DOPs.

What you need to do is use the Gas Extrapolate DOP, along with an SDF generated from the original volume source SOP, to expand the vortex's reach. This means you need to make a surface SDF in SOPs that's large enough to handle the widest bounds that your vortex would need to reach. You then have to source v to a temporary field instead of directly to vel, run Gas Extrapolate on that tempvel field, then use Gas Linear Combination to add tempvel to vel and complete the sourcing operation.

extrapolate_vel_toadstorm.hiplc

[Ultraman]

1 hour ago, toadstorm said:

I have a DOP solution for you, but to be honest you might just want to make your vortex bigger in SOPs rather than handle it in DOPs.

What you need to do is use the Gas Extrapolate DOP, along with an SDF generated from the original volume source SOP, to expand the vortex's reach. This means you need to make a surface SDF in SOPs that's large enough to handle the widest bounds that your vortex would need to reach. You then have to source v to a temporary field instead of directly to vel, run Gas Extrapolate on that tempvel field, then use Gas Linear Combination to add tempvel to vel and complete the sourcing operation.

extrapolate_vel_toadstorm.hiplc

Thanks a lot Henry , that what i wanted ..