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Mantaflow - liquid refuses to rise above level of inflow object
Confirmed, NormalPublic


System Information
Operating system: Windows 7 Pro - 64-bit
Graphics card: Nvidia GeForce GTX 1060 6gb

Blender Version
Broken: blender-2.90.0-fd8d245e6a80-windows64
Worked: 2.83

Here is what appears to be a bug in the Mantaflow liquid calculations in Blender 2.90

In the first Blender file - manta_vol_bug.blend - the inflow object is within an effector-collision object. When the simulation runs the level of the fluid refuses to rise above the Z-axis of the inflow object. This behaviour does not happen with this file in Blender 2.83

It must also be noted that there is a severe difference of the liquid inflow rate using the same simulation numbers between version 2.83 and version 2.90. That may be a problem on its own, but I cannot say if this has any influence on the Z-axis volume bug that I am seeing.

I have uploaded two video files of the rendered results of this file.

I have also uploaded a second Blender file - mantaflow volume_bug 02.blend - where the volume flow relative to the Z-axis of the inflow object is more obvious. Strangely enough, this file when loaded into Blender 2.83 will show the same incorrect behaviour.

Event Timeline

Richard Antalik (ISS) changed the task status from Needs Triage to Confirmed.Mon, Jun 22, 5:58 AM

This problem is now showing up in the latest release: v2.83.1 LTS