Computer Graphics Stack Exchange
Computer Graphics Stack Exchange

Questions tagged [fluid-sim]

15 questions
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How could I check the correctness of my result of fluid simulation?

I wrote a particle based fluid simulating program. It's hard to tell if I get the right result. The visualized result seems reasonable, but some part of it looks weird. I don't know wether it's a feature of fluid. Is there some accurate method to…
Yyao
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Code runs differently on different hardware

I wrote a 2D fluid-solver in OpenGL (code here) some time back. While it runs flawlessly on my onboard Intel GPU, the simulation very quickly "blows-up" when same code is run using nvidia card : In the second picture, the fluid is being…
nilspin
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1 answer

Conserving Mass in Liquid Simulation

I am trying to implement a 2D version of Foster and Fedkiw's paper, "Practical Animation of Liquids" here: http://physbam.stanford.edu/~fedkiw/papers/stanford2001-02.pdf Mostly everything works, except for section 8: "Conservation of Mass." There,…
Jared Counts
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Hodge Decomposition in fluid simulations

I have just started implementing a fluid simulator based on the navier stokes equation. I am following Jos Stam's paper to do so. In this paper, it says that the velocity field must be mass conserving. Which I understand as, the velocity that flows…
Mn9
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2 answers

Rigorous and simple explanation for satisfying boundary conditions in Stam and Bridson papers

I read Stable Fluids and the code by Jos Stam and FLUID SIMULATION SIGGRAPH 2007 Course Notes by Robert Bridson. The boundary conditions in the two papers are different in my sight. I don't understand them. How are these two ways related to solving…
Anas Alaa
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4
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Finite difference wave equation shown in paper is wrong?

I'm trying to produce wave surface animations, and I came across this paper: Fast_Water_Animation_Using_the_Wave_Equation_with_Damping. In the paper they go to provide the following equation: At first I just blindly implemented this, but soon saw…
Krupip
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2D metaballs with marching squares and linear interpolation

I struggle do understand how linear interpolation works in the marching square rendering algorithm context. I created simple example in GDScript (Godot) of random floating metaballs to demonstrate the problem: extends Node2D class Blob: var…
Arsenius
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Rendering Fluid Simulations?

I've read about Lagrangian and Eulerian fluid simulations and here's what I take from their methods: Lagrangian - Simulating fluid particles by calculating displacement for each particle Eulerian - Simulating fluid particles by calculating…
Kukuh Rahmat
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Jos Stam's "Stable Fluids" boundary conditions

In the paper Stable Fluids by Jos Stam, I am confused about the boundaries in the set_bnd function in the code. I don't know what kind of boundaries is this. Is it Neumann boundary condition or Dirichlet boundaries? Here is the set_bnd function;…
Anas Alaa
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How are fluid simulations handled in Computer Graphics?

How are fluid simulations handled in Computer Graphics? For a novice, there are hardly any novice friendly tutorials explaining how particles or fluids can be simulated. Things like smoke, crown splashes and fog are they animated by artists as…
Arjan Singh
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2
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1 answer

Fluid sim: CPU vs. GPU

I have very recently started looking into real-time fluid simulation. Idea is to make a game that would use 3D fluid simulation as a core gameplay mechanic. Looking around the web, I found this article that compares the performance of fluid…
Karlovsky120
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Having trouble understanding advection from GPU gems fluid dynamics example

So I am trying to implement a fluid simulation, as described in Chapter 38 of GPU Gems. I am also drawing heavily from the excellent implementation by Pavel. Where I'm getting a bit stuck is with advection. So as I understand it, advection is the…
sak
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How to extract surface of smoothed particle hydrodynamics smoothly?

I'm working on a fluid simulation project where two spheres are simulated using smoothed particle hydrodynamics (SPH). I have generated two sets of particles inside and on the surface of a sphere. You can see the result in this picture: scatter plot…
Hassan
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Rendering a particle system as a smooth blob

What is a good algorithm for rendering a particle system as a coherent mesh, in realtime? I am running a smoothed-particle hydrodynamics fluid simulation, and I would like to render the particles not as balls but as a body of water. I understand…
AnnoyinC
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Particle & Fluid Simulation: Where to learn?

Where can I learn about particle and fluid simulation? Is there a good book available? I want to couple volume rendering with fluid/particle simulation to be able to finally render smoke and ocean with foam etc. Is there a chapter in PBRT on it?
Arjan Singh
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