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Int Pressure
Internal pressure goes from 0 to 1, and simulates the forces between nearby particles and pushes them apart - this makes the fluid fill a greater volume.
Ext Pressure Scale
This parameter goes from 0 to 1, and tries to limit a fluid’s expansion tendency and can be compared comparable to atmospheric pressure. Particles tend to "stick" together with higher values. The substeps and iterations settings in the "Scene" node's → "Solver" tab influence how this parameter acts on the fluid.
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