fluid jet simulation with 1 dimensional equation
 

Hi All:

I'm in a computer graphics community and trying to simulate fluid jet. It's not in full 3D space. The axis is fixed, and need to see the change of the thickness of the jet along the axis while I perturb the velocity at the inlet position.

The requirement is 1. FAST & STABLE -- it should be realtime 2. need NOT be accurate -- if it 'looks' realistic, that's enough 3. should be able to handle the breakup without much hassle

I found a work by Jens Eggers who used 1D fluid equation to simulate drippling faucet. He derived the equation from NS equation in cylindrical coordinate. I actually got the source code from one of the authors, but it is too slow and complicated as a graphics application.

Can somebody give me a reference or advice?

Re: fluid jet simulation with 1 dimensional equati
 

You may want to the website, put your mouse on the jet figure, then you will see the movie.

http://math.uci.edu/~jskim/simulations.html

Junseok

Re: fluid jet simulation with 1 dimensional equati
 

sorry, I didn't read your post in detail, I missed some the calculation is slow and is not suitable to your case, what I meant is that it is not real time simulation.

Junseok

Re: fluid jet simulation with 1 dimensional equati
 

But your simulation looks really cool! Did it use full NS solver or simplified 1D solver? Do u think it would be possible to simplify your code somehow to make it very fast? ( again, accuracy doesn't matter much )

Re: fluid jet simulation with 1 dimensional equati
 

The numerical code is solving full NS in axisymmetric domain (2D) and for the interface capturing I used phase-field model (Cahn-Hilliard equation), the basic idea is very similar to popular level set method. Jet simulation is complicated process, involving gravity, oscillating inflow velocity, and surface tension effects.

I am not sure how fast is fast in your case. The meaning of fastness is relative.

Junseok

Re: fluid jet simulation with 1 dimensional equati
 

As you may noticed from my simulation result, after pinch-off the droplet has inverted curvature, which is 2D effect, from the 1D you can't get that one because it has multiple solution from 1D point of view.

Junseok