Questions tagged [fluid-simulation]

Questions about the Fluid simulation systems in blender. Blender has two systems for simulating liquids, a SPH (Smoothed Particle Dynamics) system integrated with the particle system, and a Lattice Boltzmann method which can be used create a variety of simulations.

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25
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1answer
2k views

Physics cross-simulation interactions?

For example, rigid bodies and fluid. I know it's kind of possible by setting the rigid bodies as fluid obstacles, but it's not "true" interaction in that the fluid does not affect the rigid bodies... ...
13
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1answer
4k views

Bake Fluid Simulation via CLI or Python?

I would like to run a fluid simulation on a headless Ubuntu machine I have lying around. I did manage to find a bug report on the issue but to no avail. Has anyone else had any success? Or perhaps a ...
6
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2answers
7k views

Water ripples / waves on the surface of an object

I would like to create a character made of water. To do this, I am trying to do it with a simple sphere first. I tried to apply modifiers to the sphere to get it to move and undulate like water ...
3
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2answers
1k views

2D flow simulation over a surface

I'm very new to blender but keen to learn more. I have used a lot of 2 and 3D modelling packages as well as a number of GIS applications. I'm just trying to work out if I can model a fluid flow over ...
12
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2answers
9k views

How to bake multiple fluid simulations in one scene?

If we understood correctly, Blender does not allow more than one domain for fluid simulation in a given scene. This means that any inflow (fluid) object will be transformed into only one domain object ...
11
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3answers
5k views

Different materials for each fluid inflow?

How to assign a different color / material to each inflow object in one simulation (bake)? In the following example we tried to mix two inflows and experience the mixing between the two fluids. ...
9
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2answers
38k views

'Bake data' button not visible in fluid options

(new to blender) i am trying to create a fluid sim in blender 2.83 but in my physics tab under domain there is no 'bake data' button in the options. It's there in all the tutorials i've watched but i ...
4
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1answer
2k views

Jet stream of water

I would like to simulate a stream of water like the one in the picture, but I don't know how to simulate the fast-moving, white water. Should I use particles to simulate foam or is it much better to ...
26
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1answer
3k views

Is it possible to simulate an egg?

Is it possible to simulate an egg? Specifically, I was wondering how to handle simulating the yolk. I was thinking fluid simulation, but it seems you can't a specify different viscosity for ...
18
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2answers
5k views

How to make an object appear to be buried in sand?

My first thought was to use a fluid simulation, but that would act too much like liquid and too little like sand, unless there's some way to configure it differently. Ideally, I want it to look like ...
15
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2answers
2k views

Ink on Porous Paper or Water Bleed Effect

I have seen some rather incredible results out there using smoke and dynamic paint, and as such, I am curious if anyone can come up with a clever simulation of ink onto paper, or, closely, ink into ...
10
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2answers
12k views

How to stop fluid inflow?

I have fluid simulation with an inflow object. I want the inflow to go for 2 seconds, then have the inflow stop (so no more fluid is added) but keep the simulation going (so the existing fluid ...
4
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1answer
2k views

How To Make A Solid Object Drop To The Ground Like It Was Liquid

So I have a simple bouncing ball animation, but I just wanted to something "weird" for the ending. Is there a way to change the ball's material on the fly, where after the last bounce it changes ...
12
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1answer
11k views

Simulate objects falling into water

On the blender website there is this image: What would I need to do to recreate this, cubes and spheres falling instead of fruit would be fine. I believe this uses the cycles render I have never used ...
3
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1answer
3k views

Prevent fluid to flow through the walls of an obstacle

I am trying to make a fluid simulation flow out of the orbits of this skull (I hope this doesn't violate any guidelines), as a little experiment / practice with fluid simulation. The result is not ...
16
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1answer
6k views

How to apply gradient color change in an animation

How to apply color gradient change on a fluid such as in the following figure? The method should be capable to apply to all frames in the animation automatically. Consider it as simulation of being ...
10
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2answers
2k views

How to resume baking fluid simulation?

It happens sometimes that after finishing bake (e.g., for fluid simulation) we wish we could continue the simulation for two more seconds :( How to use the ...
6
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1answer
8k views

For Fluid Simulation, what do the Start, End and Speed settings mean?

How do the Start, End and Speed settings work? Isn't the Speed setting determined by the Start and End settings? For example, say I have 120 frames (at 30fps, thus 4s), and I set "Start: 0", "End: ...
7
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1answer
2k views

How can I make water follow a path?

How can I make water follow a path?
2
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1answer
551 views

Fluid, object, childof constraint animation - won't work

See this video for project example It's a simple project. I'm trying to create a fluid simulation flow out of a cylinder, but the cylinder has a "childof" constraint, paired to the cube above it. The ...
20
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1answer
5k views

How to make a wake behind a boat

The advanced students in my class are about to animate the dual paddle wheel steamboat 3D model that I gave them. I'm wondering if it is possible to attach a 'V' shaped wake behind it, perhaps on a ...
10
votes
1answer
7k views

How to avoid fluid appearing outside collision objects?

In fluid simulation as it is done on a grid with a resolution definable even choosing a higher value for the resolution (as in our example below, 200) it is not enough to have a realistic shape of the ...
10
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1answer
2k views

How can you use vector blur in Cycles with fluids?

I know (at least I believe this to be true) that using cycles motion blur wont work with fluid simulations when rendering, however, I know that vector blurs can be used in place of motion blur. With ...
12
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2answers
8k views

River simulation - different approaches than fluid simulation?

I am in the middle of a project which needs to have a river flowing in it. (You may be familiar with my recent questions; they are all related.) Just for reference and imagination, here's a preview of ...
8
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1answer
694 views

Fluid Simulation: Inflow is stretching to the edge of domain when baked

Here you can see an animation of my fluid sim. The inflow is that small black circle. For some reason, the fluid flows in from the space between the inflow and one edge of the domain... Here are a ...
2
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1answer
4k views

Water Spray Simulation

I am working on a project where water needs to be sprayed so to form 60 deg full cone from the spray nozzle in an animation. I have tried it with inflow and v cylinder but when water leaves out it ...
1
vote
2answers
12k views

Fluid simulation domain visible

Whenever I try to do a fluid simulation, the fluid domain remains visible. I have tried:ctrl+a-scale, turn on/off visibility for render/viewport Here's a video demonstrating my problem: https://...
16
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4answers
15k views

Water leaks through obstacle

Every time I try to hold water with a obstacle, it leaks out. Here is one example I have made. The shape has no holes, and the water is partially contained but slowly leaks out. This has occurred ...
17
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4answers
10k views

Why does the water keep escaping in my fluid simulation?

I am trying to do a water simulation. I have a small cup that I have created in blender (as an obstacle) and my water source (just an oval). My domain box is large enough to encompass both the glass ...
14
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1answer
2k views

How to attach colors (e.g., gradient color) to fluid particles

This is follow up question based on {this post}, indeed. The question is how to attach color attribute to fluid particles? For example when a part of colored fluid (as explained {here}) ...
2
votes
1answer
2k views

How to make this glass more realistic?

I have made this image : As you can see there is something wired going on with the liquid of inside the glass, in fact, I'm doing a fluid simulation here, it looks like the mesh of the fluid doesn'...
1
vote
1answer
8k views

Blender MantaFlow ... no visible result!

Im really wondering why the MantaFlow branch does NOT show me anything. What I mean ... I made a simple cube as a domain, than another one as an obstacle and finally a sphere as a flow. Leave the ...
15
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2answers
2k views

How can I make a fluid simulation in game engine

Is there a way to simulate a fluid in the game engine? It doesn't have to be 100% realistic (but not a cycling 2D animation). It just needs to be recognizable as water. Optimally, there should be a ...
6
votes
1answer
933 views

Hair Particle system and Fluid Simulation interaction

Making a scene with grass made with a hair particle system in a fluid simulation. I was wondering if there is any way for the hair particles to be able to sway based on the fluid simulation. If so how ...
5
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2answers
1k views

Mantaflow: bake always crashes, cannot be resumed

I have problems baking a smoke simulation with Mantaflow, I tried Blender 2.92 and 2.93 Alpha. When baking a (not very complex) simulation, Blender always crashes at around 30% of a 250 frames ...
4
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1answer
2k views

What is the minimum size requirement for a Fluid mesh object in a Fluid simulation?

What is the minimum size requirement for a Fluid mesh object in a Fluid simulation? I've heard and read that if the mesh is too small, it may not act like fluid properly when baking. But, I don't know ...
4
votes
1answer
493 views

Displaying airflow inside of an engine model

Okay so basically I have a model of an engine. The purple shows where all the gas and yes gas not liquid should go. It must collide and be held in by a couple moving parts. The first thing I tried ...
2
votes
1answer
425 views

Fluid Simulation, make the fluid to be absorbed

I have a fluid falling on top of a plane. I want the fluid (water) to be absorbed by the plane, like a cloth would do. How can i do that? Thank you
1
vote
1answer
767 views

How to melt an object then reverse the melt into another object

Hi I am trying to have a text that says "Hi" then melts into liquid, then that liquid reverse melts into text that says "my name is" then melts again. Does anyone have any idea how i can do this?
4
votes
1answer
3k views

How to make my water look Murky?

Blender noob here again! I'm working on making a Swamp scene and I'm curious how I can make my water look murky/smokey. Would I need a smoke simulator in the system too? Or is it a materials thing? ...
3
votes
1answer
2k views

Is it possible to pause and later resume a fluid sim bake?

I have a pretty heavy fluid sim bake going on... by pretty heavy I mean I estimate it will take two weeks to complete! It is likely that during that time I will sometimes want to use Blender for ...
3
votes
2answers
2k views

How to fix this physics problem?

Hello everyone, How to fix this physics problem, the objects pass trough to wall. I increased the Steps per second and Solver iterations in scene settings > Rigid body world. Also, I set the shape to ...
3
votes
1answer
2k views

Fluid: How to convert the simulation to a series of meshes?

Once you've baked your fluid simulation, you can apply the Fluid in the Modifier panel in order to get one mesh that you can edit etc... But how can you get the whole series of meshes, i.e. one mesh ...
2
votes
1answer
414 views

Fluid gets Stuck in the Middle of Pipe

I am trying to simulate fluid running through an array of pipes into a destination tank. The fluid runs fine through my system until it reaches a bend in the pipe and then it just stops. The pipes ...
1
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1answer
2k views

Animating a fluid water fountain

I was trying to make a water fountain and animate water flowing through it. I added the domain and inflow to the mesh but couldn't make the water flow out of the mesh/fountain. It just drops straight ...
1
vote
1answer
566 views

How do see fluids through glass (Eevee)?

I don't see my fluid inside the glass, but i can see the object inside the glass. Does somebody know, what i have to change, to see fluids through glass? Or is this not possible in Eevee? Can i fake ...
1
vote
3answers
414 views

Why does my Mantaflow waterwheel not work?

Apologies if this doesn't light correctly, I omitted the HDRI I was using to save space for upload and download of the .blend. Plug in your HDRI of choice and the scene should look fine (or turn off ...
1
vote
2answers
508 views

How to make fluids come out in a local coordinates?

I'm trying to make a liquid simulation with Mantaflow where the flow of the liquid respects the flow object's local rotation, so it looks like water spraying in different directions. It looks like the ...
0
votes
2answers
505 views

How to fix the weird surface in fluid object

Hi Guys, this is my first time to make a fluid simulation. However, I got some problem. The surface looks so weird. I am trying to make an animation so I do not decide to use sculpt mode to fix it. Is ...
0
votes
1answer
119 views

Mantaflow use in blender

.Blend file I am a blender beginner and after watching some tutorials online I figured I'd give modeling and animation a try. I am trying to make an oil hourglass animation that will move the liquid ...