Problem with small fluid inflow

I have a kitchen scene where everything was modeled using real world values(metric) and I wanted to make the tap run some water.

But for some weird reason the Inflow object that is the size of the tap’s hole is not giving me a continuous stream of water. It is instead just dropping a few droplets like big giant particles. I’ve bumped the resolution up to 200 and nothing seems to change.

What’s causing this?

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Do we have to guess all your fluid settings and how you have set up the scene aor are you just going to supply a demo blend file for us to review ?

What inflow velocity are you using
Supply a file !

I apologize. I cleaned everything just so to include the sink. You’ll need to bake it, but it was pretty quick on my side.

I did this to keep the file small so I can upload it here.

Kitchen_Sink.blend (1.48 MB)

The inflow object is ridicously small. It has a scale at 0.005 and its dimensions are below 50 µm.
For a domain of 80 centimeters, it corresponds to a 1/160000 ratio.
At scale 1, dimensions of your inflow object are below 10 milimeters. 1/80 of your domain It is still really small inflow.
You should not define such large domain compared to your inflow.
Instead, you should make 2 simulations. One per sink basin.

Oh wow. Then the Fluid system is very limited with what it can do then. If I had a scene where a water hose is shooting water over 5 meters, and the inflow is obviously small it would never work or look right! Let alone doing rivers or tsunami’s…

Makes me question the usefulness of this Fluid system beyond just filling boxes with water as tech demos…

It is really ancient and was done to create simulations of fluid going from a bottle to a glass, or chocolate on a fruit, a biscuit.

Think of it, did you really ever seen a scene like that ?
What you see is 10-15 centimeters of mesh that looks like a turbulent fluid, then you have 2 meters of fluid mesh that is as cylindrical than the water hose and 2 meters of empty hose. You never thought that it could be a moving domain.
You don’t need a fluid simulation for that sequence. You can achieve this by a highly distorted, displaced front side of a cylindrical shape that moves from start of the water hose to its end according to an animation following a spline. plus a little bit of particles.
If you cut this sequence by close-ups of inside of the tubes where fluid simulations are used, you think that the whole video was to done like that. But it is an illusion.

The same way, rivers and tsunamis are often displaced mesh partially masked by particles.
Or when they are made by Hollywood, they are simulations that correspond to a resolution of 512, 1024, 2048 cells … computed on cloud, simulation farms.

OR I can just buy a copy of Realflow for C4D and have better results and a much better time doing it. I just wanted to know if blender could save me some bucks and it can’t. Fluid sim is another feature of blender that is in badly need of updating much like the hair/fur particles.

So I better start saving for it.

Yes. Realfow is at all points greater than Blender’s fluid simulation. It is faster, easier to use etc…
But adapting scale of simulation and being careful of final mesh density are requirements that you will encounter in Realflow, too.

I tried increasing the fluid inflow diameter to see what sort of results I could get.
Here’s the results, with the pertinent information.
(Excuse the poor materials, they were just meant to be quick tests).
I also changed the fluid simulation Time End from 35 to 8 seconds to get a closer to real time result. (as well as a few other modifications).

Fluid Inflow object diameter: 4.87 mm
Fluid domain resolution: 400
Surface Smoothing: 1 (default)
Surface Subdivisions: 0 (default)

Fluid Inflow object diameter: 1 cm
Fluid domain resolution: 500
Surface Smoothing: 2
Surface Subdivisions: 2

Using multiple domains (one for each sink):

Fluid Inflow object diameter: 1.2 cm
Fluid domain resolution: 400
Surface Smoothing: 1 (default)
Surface Subdivisions: 0 (default)