Crown splashes and milk drop photography recreation

Support Particles and Physics Simulations
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Hi everyone,

I’m brand new to Blender, and only have Trimble’s Sketchup for a 3D background, so I’m treading water in the deep end of the swimming pool while I’m trying to learn and get up to speed with Blender. But I have a general question regarding the fluid dynamics aspect of Blender:

After playing with it for a few days, I’m still unable to create a realistic “crown splash”, nor a “milk drop photography” style splash. These are needed for a current project, and honestly, I’ve been a little disappointed with the results so far, though I hope it’s just my inability with the program.

But I’m afraid to waste any more time with Blender’s fluid simulator, if it is unable to create such a result.

Would I be better off using the RealFlow software, or Houdini? I just hate to shell out the money for those types of programs if they can’t manage to make a crown splash any better than Blender can.

Any tips or advice for this pursuit would be appreciated!

Thanks,

Eric

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Just to be sure: Do you need this to be animated or is it for a still image?
If it’s for a still, just model/sculpt the splash to your liking. Sure, this might be quite some work, but on the other hand you have total control over the splash shape…

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Here, an old tutorial: Fluid simulation to create photo-realistic Splash by Andrew Price / blenderguru.com

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crown splash photography is achieved with a flash duration of something like 1/65000th of a second, i’d hate to think how long the simulation time would be to process at that level of detail

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You´d be much better off using these two programs if you can spare the money. The Blender Fluid Sim is severely limited. I have done commercial work with it but you have to know pretty precisely what it can do and what it can not. And sometimes you have to invest quite some time in faking stuff and covering up bad areas of the sim. And it is very difficult to control.

Since Houdini Apprentice is free and Houdini Indie very cheap, perhaps it is possible to create a good looking fluid sim there and then export and render it in Blender. I read that Indie exports to Alembic (don´t now if Apprentice does), so I assume it exports to fbx or obj or something like that as well.
If that is the case it should be possible to generate an obj sequence of your Houdini fluid in Blender.

I you try that route please post if it is successful.

Then there are the Fluid particles in Blender which are SPH particles. You can combine them with a plugin called Cubesurfer. I´ve only got Cubesurfer to run in Blener 2.74, though, but maybe that´s not a problem.

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Fluid particles with pyroevils cubesurfer is good. but hard work.
i’ve been looking at houdini fluids and it is much less low level, a lot of the grunt work is taken of but i’m not sure how easy it would be to take the simulation from houdini indie into blender for lighting/shading/rendering and would you be importing a mesh into blender or a particle system?

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Have you gotten cubesurfer to work with anything different than Blender 2.74?

As for the Houdini Fluids: I assume it is meshed somehow. If it is meshed it can be exported to obj. If it can be exported to obj a whole sequence (one obj per frame) can be exported. Then we can import all the obj into Blender and animate their visibility - i.e. make every mesh visible for a single frame.
Or stream the objs somehow from disk, similar to the Blender Fluid Sim but I´m not sure if that is easyly possible with Python. It would be very useful, though, as it would be better than having al these large mesehs in on single .blend.

I guess the Houdini fluids also use some sort of extra particles to generate foam and spray and stuff like that. This could probably be exported separately somehow. As Point Cloud perhaps?

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i’ve got cubesurfer running on both 2.76 and 2.74 os x yosemite.
time for cubesurfer to run is very dependent on what you have in terms of particle system, it may take forever to build a mesh, best thing to do is run blender from a terminal shell so you can see what it’s doing.

attached video was made in 2.76 with cubesurfer and a fluid particle system.
potential for using Houdini sounds promising will investigate further

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Cool, thanks for the link, Burnin and Nigel for the video. This looks useful for these “controlled” splashes often seen in corn flakes or shower gel commercials.
Looks like I´ve got something to do over the christmas holidays.

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Thanks to all of you for your suggestions and ideas. I’ve been distracted with other projects over the holidays, but as they finish up this week and next, I’ll be back onto this.

Eventually, these will be a series of stills to illustrate a book, but the idea of creating animations to pick and choose certain frames from sounds exciting, but is probably way beyond my current newbie skills with blender.

@@IkariShinji
That’s a neat image! That’s similar to what I’m hoping to create, except I’d like to add the additional rebound droplet and further collisions so popular in milk drop photography. Crown splashes are I’m headed. I’ll start in earnest soon on trying to recreate what you’ve made there. Thanks for showing me it can be done!

Blender is amazing–I hope I can figure it out!

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I’m surprised that more people haven’t tried simulating Edgerton’s famous milk drop splash. So I was glad to find this thread on blenderartists.

I’m not an artist. (I’m an engineer.) So my render isn’t realistic, material and lighting-wise. But as an engineer, I spent about two weeks obsessing, trying to get Blender’s fluid sim to reproduce the milk drop coronet. (Just for fun.)


I managed to get a semblance of a coronet.

postimg.org/image/s7panklrf/

It’s not easy getting a true coronet.

First, it’s not easy in real life. There’s a white paper about doing it - it involves Reynolds and Weber numbers. (Since I can’t post url’s, you’ll have to search for “Complexities of Splashing.”) Part of the trick requires that the surface liquid be 20% of the drop diameter. (If you look at a youtube of Edgerton’s experiment, you can see the bottom of the container when the milk drop splashes.)

Second, as @Lumpengnom said above, the Blender fluid sim (v2.77a) isn’t that good. Frankly, I’m amazed it worked as well as it did.

It seems that Blender can’t handle a thin sheet of fluid. It needs a certain thickness of fluid for calculations.

Here’s a psuedo-link to a video with the Reference image first, and my sim second. (I slowed the first part of the splash down 50% in my video (post-processing) and sped up the part where the fluid fills the void.)

vid.me/zbCG

I set the scale of the domain in millimeters and the drop is in microns. I played with viscosity and gravity, ratio of drop size to fluid depth, size of domain. Render is at 150.

If some expert figures out how to get Blender to simulate a true coronet, I would be interested in seeing the .blend file.

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Hello ErgonomocMike. I,ve just saw your topic and it’s really interesting for me because I actually work on a milk coronel on Blender ! But finally I’m not sure to understand how you did your image ? Was it made on Blender or with on other software ? And if it was made on Blender, please could you tell me how did you make it (all the links are dead) ?
THX :slight_smile:
Zak’

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I just saw this today as I serched the web as I attempt another milk drop render using FLIPS fluids in Blender 2.82. I got better results with FLIPS and will try to post something soon.

BTW, to answer your question, the image I posted in this forum was from a Cycles Render. It was probably one of the jpg’s from an animation of the render.

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Here’s my latest attempt at both the famous milk drop crown (see the video) and the single drop at the top of the splash using FLIP Fluids in Blender 2.82.

The FLIP documentation says that objects smaller than 20 cm don’t play well in FLIP. So that’s the size of my drop. Also, I don’t know if the “drop” is the volume of the sphere or just liquid on the mesh shell. (It appears to be the volume, from the way the simulation behaves when the drop hits.)

I’ve got a couple days invested in this. But I’m just a novice. Perhaps someone with more knowledge can take my blend file and get it to work exactly right. There are some parameters in FLIP that aren’t yet documented (positive and negative smoothing on the mesh) that could be played with. Also, I need to get more surface tension and perhaps adjust the ratio of FLIP to Blender physics so that the crown will break up into points, instead of sticking together like it does in the video. I used a viscosity half way between water and milk - but the FLIP doc says that the viscosity setting isn’t Real World. So I should have played with that more too.

I hope someone can get a more realistic crown and drop. (From what I read of the original experiment, it wasn’t very easy to get right in the Real World either. Size of drop, depth of milk layer, etc. had to be just right.)

The link to my video of the milk drop: https://jmp.sh/2YriTxj
My blend file: https://jmp.sh/j9Y5z2R

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You only need Blender 2.82
It is jus

splash
splash1920×1080 231 KB
t you need practice
This one is pretty simple mesh but you can add particles and different collision objects and shapes until you get the desired splash

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After Zeluazeman’s post, I remembered that I had totally forgotten that the FLIP Sim (probably still) needs a mesh in the receiving liquid. So I added one.

I also tried a mid scale version. About 350 samples.

Getting better. But not there yet.

I also find a guy on youtube who made a classic crown splash with a FLIP Fluid add-on. I looks to me to modeled in a big scale. (A least a meter.)

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If you try a deeper mesh in Z axis and use more or less initial velocity and different object falling angles etc you will get it
There are many factors in this case

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Here is my modification of your .blend.

The sphere is hand animated to fall. Once it comes in contact with the fluid surface the keyframes switch to slow motion to animate the sphere through the fluid surface while its scale expands. Starting off, with gravity set to zero, all fluids rises upon impact.The gravity is keyframed to slowly increase after the splash lifts for several frames.

Untitled-1
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ap_28_milk_drop.blend (757.7 KB)