Problems with fluid simulation

Support Particles and Physics Simulations
1

I’ve tried to simulate a small amount of liquid flowing out of a mug, but for some reason it behaves strange (as seen in the screenshot). Is there a way to solve this issue?

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The fluid domain includes the whole surface beneath the mug, as well as the mug itself. The sphere inside the mug is the source of the liquid and set to “fluid” (not inflow, etc.).
Volume Initialization is set to “both” for all 3 objects (surface, mug and sphere), changing it to “volume” or “shell” doesn’t fix the problem.
Slip Type is set to “no slip”, but again, the other options don’t change anything about the issue. Gravity is turned on.

Please let me know if you need additional information to solve this problem!

2

Is the mug in this position/rotation since the beginning of the animation?

3

Yes, it is.

4

Thats the problem. You need to start the simulation with the mug in the normal position. Then you turn the mug with animation… For the mug to be in this position somebody needs to move it, so that the fluid flows out of it, right?

  1. Make the mug hole point upward, place the fluid in it
  2. Only start moving the mug after 10 or ,20 frames idk… so that you have time for the fluid to adapt to the concave surface of the mug.
  3. Caution not to move it too quickly, otherwise it will splash everywhere(unless thats your goal)
5

Thanks for your reply, I’ll try your solution as soon as possible! The main issue is that once the fluid touches the surface (table) below the mug, its edges seem to bend upwards (screenshot). Will your solution also solve this problem?

6

Check normals on the table. You dont need to use the table as a collider for fluid… Just put the lower edges of the domain at the surface… (Unless you want the fluid to drop on the edge of the table)…

Try reducing the size of the domain as much as you can… It speeds up the calculation…

7

How do normals affect the liquid? Should I remove them entirely?

8

About normals, you just need to “make normals consistent”… for the mug and for the table… go to “edit mode”, select all verts, press SHIFT N

9

Ok, thanks!

10

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You check normals in this overlay menu(in edit mode)… they need to be pointing outward… (these small blue lines)

11

I just tried everything, including modifying the normals and removing them alltogether, but the fluid still keeps doing weird stuff.

12

send the file

13

I’ve uploaded the file here

14

are you using 2.79 or 2.8?

15

read the manual. the current blender’s fluid simulator has got many limitations and is so primitive for being customized and creating realistic-looking water and fluids. After 2.80, Blender will have implemented the Mantaflow Fluid&Smoke Physics which is competitive to industry-standard 3rd party plugins that Maya, 3ds Max, Houdini and C4d use.

16

@SirCruX I’m currently using 2.79b

@robertzaku1 Does that mean that this particular issue isn’t something I can fix (yet)?

17

report it to developer.blender.org

18

have tried it here… i think you should make another mug… its leaking like crazy… idk why its happening…

19

Ok, thanks for your help nonetheless!

20

I had to make fluid simulation for a project recently… it gave me a lot of headache… I advise you to wait for mantaflow in 2.81… maybe… or if you preffer… you can buy FLIP FLUID addon on blender market.