Advecting velocity by itself

[RobiDoes3d]

Hey everybody, 

I'm trying to make a custom smoke solver. However, when I try to advect vel by itself it doesn't work as expected. I want the field to expand outward, like this:

But it only expands to its boundary. like this:

 

Does anyone know how to fix this? (without using divergence)

 

advectingVel.hip

Edited February 1 by RobiDoes3d

[Librarian]

@RobiDoes3d
In Houdini, the Gas Advect Node mircoslover can be used for advecting fields based on an existing field. If we have some interaction between fields, The Gas Calculate node can be used to copy information from one field to another. or use this method to blend in endless ways
 

also not Gas advect field  Node
 

Edited February 2 by Librarian

[fencer]

gasresize should do the trick

advectingVel_v02.hip

[RobiDoes3d]

@fencer Thanks, I never thought of using that node outside of a normal sim setup.

@Librarian That level of control would be great, unfortunately,  I still don't understand how you did it. How do @dest, @source, @blenda, and @blendb control the sim? Why is it only calculated on the 1st frame? ...If you haven't already deleted the .hip file, I would love to take a look at it

[Librarian]

@RobiDoes3d I just combined those methods with this 3 days old post . Don't need to be on first Frame, it's Just Test.
https://forums.odforce.net/topic/52695-how-can-i-use-the-microsolvers-to-resize-a-density-field-dynamically/#comment-240203

 

[Librarian]

and this file it's a Must for this stuff .
 

simpleGasSolverInTenSteps.hipnc