liquid mixed in steps using multiple grids

[lander]

1. I generate liquid in a small container by injecting from ID at the bottom of the geometry.
2. the liquid is emptied into a second container with water.
3. the resulting mix is poured into a third bucket.

The simulation volume in the scene as a total is big so I want to use multiple grids to keep the sims efficient.

Issues
a. I fill (inject) the first container with soap but even if I fill it to the brim the fluid reduces down to nothing as I stop the discharge. So there is nothing left to pour into the second container.

b. The water container is filled (brush) source set to non solid.
Do these two grids have to be the exact same cell size?
(I couldn't find the cascade sample scene)
I use the first PhoenixFD001 as a source set to brush with a discharge 100 ( when using the brush option does it matter what the discharge is set to?)

c. Do I use the RGB chanel to manage the shaders when rendering? (It's not a full frame mix (ink in water) shot so I can probably fake it in post if I have to)

[Ivaylo Katev]

"I fill (inject) the first container with soap but even if I fill it to the brim the fluid reduces down to nothing as I stop the discharge. So there is nothing left to pour into the second container."
sounds like low resolution or too thin walls of the container, can you post viewport image?

"Do these two grids have to be the exact same cell size? "
no need to have the same resolution

" Do I use the RGB chanel to manage the shaders when rendering? (It's not a full frame mix (ink in water) shot so I can probably fake it in post if I have to) "
i suppose yes, for the transfer you have to use phoenix texture.

in general, it's good to see this tutorial, if you have still not seen it.

[lander]

Thank's I'll have to be more careful with the grid/thickness settings.
I'm running phoenixFD_adv_22000_max2015_vray_30_x64_25295 and I can't find a "strong surface mode"

Isn't the PhoenixFD sim multi-threaded?

[lander]

As soon as I create a PHXsimulator my framerate drops from 140 to 1.5. that is without simulating anything.
I havn't seen this before so I wonder if maybe I upset some setting in Max. I deleted the 3dsmax.ini but that didn't make any difference.
It's a low end workstation I7 Max2015 12Gb ram with 2xGeForce GTX 650
Any clue as to what may cause this?

Is it possible to mix different liquids? My fluids doesn't seem to mix. I thought activating RGB would do the trick.

[Ivaylo Katev]

what you mean with "framerate"? the viewport refreshing frame rate? i suppose you have old cache files and it tries to display some content

[lander]

So how do I delete that?

I have restarted max and it's only getting worse. Now my PhoenixFD simulation grids look like a messed up "normal pass" -that would be the preview of RGB/Wavelet
If I open up any scene that has no PhFD in it my framerate is in the 240fps area.
As soon as I click to start drawing a PhFD simgrid the framerate drops and everything lags.
I'll start by trying to change to newer nightly build.

OK I upgraded to the latest nightly. Much better.

[lander]

I have sent a file to you (phoenix@chaosgroup.com)
There are two issues that I need some help with.
1. I fill a jar with fluid using brush mode the way the winebottle is filled. But the surface is very disturbed and does not settle (it boils)
2. I have a second simulator that empties into the first. It's not solid and not included in the first ones simulation but it interacts.
I've been using this nighly.
phoenixFD_adv_22000_max2015_vray_30_x64_25347

At the end of the simulation I empty the jar fluid into a different bucket. And the boiling stops as the jar is about half empty.

[tashko.zashev]

Hi,

Thank you for sending us the file. As soon as we have any information will post here.

[lander]

Thank's so much. Let me know if there is anything else you need from me.

[tashko.zashev]

Hi,

Regarding point 1, due to the simulators movement from one point to another in the scenes (frames 170-207), such an liquid flowing is expected. There is an initial forces parameter that you could use to control this behavior. Dynamics > Inertial forces
Try to disable it and make another simulation tests.

About point 2, I think you need to exclude the simulator 1 from the Simulator 2 interaction list as well in order to get the requested result. If it is not the case and you need to achieve different simulation result, please provide more detailed instructions and we will check again.

[lander]

ok, thank's I'll run a test without the Inertial forces option and see if it helps.

But still isn't it odd that as the PhoenixFD002 simulation grid moves through the PhoenixFD001 the grid volume interact. Or does one volume consider a second volume to be a block of air?

[lander]

Did you compute the simulation so that you could see more than the few frames that I sent you?
To be expected it looks very unexpected to me. To me it looks like I have a jet on the right side of the jar pushing the water upwards indefinetly untill it's removed as I empty the jar and the last 30% runs out smoothly.

[lander]

I'll have to do some more R&D on my side to get comfortable with this. But as for now it looks alot better with Inertial forces "off".
But I have found a different problem. I get some nasty artifacts when rendering with caustics. And the artifacts are bucket edge related.
attached a caustic pass.

Any ideas?

[Ivaylo Katev]

well, can you provide some phoenix and vray details. for now try to switch off the light cache of phoenix, this will slow down the rendering, but very probably will resolve the problem.

[lander]

Ha ha!
I'm having a real problem with this reply. All on my side. This is the fourth time I write this. Hope the token does not expire and that I do press "submit" this time. (Ctrl+a, Ctrl+C)
Not sure what info is relevant to this so I'll send the scene to you if that's ok?

-C