Filling issue - linked to cell number?

[-greg-]

Hello,

I just got phoenix a few days ago and I'm learning how to use it. I will need to use the liquid simulation pretty soon for a project and I've been experimenting with it. I followed the tutorial on youtube and can get some water coming out of a cylinder. I've built a quick glass to try to fill it up. So now is the time to ask a probably naive question:

Here is what I've found while playing with it. If I decrease the resolution of the grid, it feels as expected, the liquid flows, and even spills out of the full glass. Now if i increase the resolution, the liquid goes out up to a certain point in the glass, and then even though more water gets poured into the glass it stays at the same level. I would think that max or phoenix is limiting the number of cells emitted? If so where should I go to change that limitation? It looks like once it spilled a certain number of cells it then stop generated new ones and it become a closed circuit. Now I've spent quite some time on the forum and tried to find out how to fix that but couldn't come up with a solution. I'm certain I'm not the only one with this issue, and I have to admit I'm probably the one at fault for not knowing Phoenix well enough. I would have thought there would be a particle age parameter included in phoenix or something like that but it doesn't seem like there is. I would assume that the greater the resolution of the grid the better the result would be? Or am i misunderstanding the resolution parameter?

Also when following the tutorial about water I can't get the box to be fully filled either, it always seem to stop at a certain level, hence the idea of a cell number limitation.

Any suggestion?

Thanks a lot.

[Ivaylo Katev]

Hi,
may we see the scene with the problem?

Regards,
Ivo

[-greg-]

Hi Ivo,

Sorry for the late late reply, have been traveling for the past week... I figured out the filling issue by playing with the discharge number, even though increasing the number too high creates a sort of overspill

Now, I am trying to fill up a glass, and get the water to stand still after a few seconds once the glass is properly filled. So far the surface is constantly moving on a 600 frames period and it feels unnatural. I'm trying different settings and will have a better idea if any of those are working or not. I might just post my video tests and share the scene later this week.

Thanks for the quick reply btw.

Greg

[-greg-]

Well,, I'm looking at the sample files and it helps a lot understanding a few things, like increasing the viscocity when the top surface is about to get still. Though it still looks a bit odd in the beer sample, the still surface isn't clean, I assume increasing the resolution would fix that?

[Ivaylo Katev]

the viscosity in the beer sample is not to achieve flat surface, but to decrease the internal circular flow of the liquid. the bubbles make this flow visible and it looks unnatural.
for flat surface i would recommend to use "strong surface mode" option with zero sharpness. for more details see the settled liquid section in the help.

[-greg-]

That makes sense, thanks for the reply I'll do some more testing. Curiously though, as suggested in the help link I am not able to animate the sharpness value, I can animate all the other values but this one.

[etown]

Noticed today that the boundary conditions for X and Y have to be set to "jammed both" for my geometry to fill properly. If you set them to "jammed (-)" the liquid just sits at one level.

[-greg-]

Thanks for the tip etown, I'll try this out as well.