We're having a problem with Distributing a FLIP Simulation using Narrow Band. We see a gap appear at the slicing seam.
We have setup simple simulations to demonstrate this, using both DOP Level and SOP Level Flipsolvers. Here's how we set it up:
Houdini: FX 19.5.805
OS: Windows 11
Oceans Shelf -> Flat Tank. Created a Slice By Plane Node in the Network -> Clicked Distribute Particle Fluid button in Particle Fluids Shelf -> Selected Slicing. One Cache sent to the Farm with Narrow Band Off in the Flipsolver, one with Narrow Band On.
Here is an image of the node setup in the Network:
Here are values of parameters within the Network:
Flip Object:
Particle Separation: 0.02
Particle Radius Scale: 1.2
Grid Scale: 2
Narrow Band (FlipSolver):
Narrow Band Bandwidth: 7
Distribution Control Null:
Slice Overlap: 0.05
Particle Overlap: 0.05
In both cases, distribution gives expected results when Narrow Band is OFF.
However, both cases show a gap when Narrow Band is ON. The small gap appears where the slice plane was placed - a gap smaller than the slice and particle overlap defined in the Slicing Control Null. In the image below, the slice plane is shown as red. Only Slice 0 is active.
Here you can see the results with Narrow Band OFF:
However, here you can see the results with Narrow Band ON:
Is there a change we need to make in the node setup when using Narrow Band? Is Narrow Band even an option when using Distributed Simulations?
Many thanks for any help and time!