FLIP fluids Viscosity?

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Is the FLIP fluid solver designed not to have viscosity (or surface tension), or is this a bug that snuck through? Or is there some other way viscosity should be calculated?
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Wondering the same
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and for friction too, seems that it has no effect
daniel bukovec | senior fx td | weta digital
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I was hoping for this too… and the ability to change viscosity per particle (think liquids with spatially/temporally varying viscosity)
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Yeah, it might be something that they've just not implemented into the solver as I believe other FLIP/PIC solvers do support viscosity.

Perhaps there's a workaround that achieves the same effect?
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I too am now wondering…
http://vimeo.com/14031860 [vimeo.com] << Flip is great… but would be cool to have the other options openly availalbe ( i'm wondering if they're still useable via the micro solvers )
Ian Farnsworth
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Surface Tension is a pretty easy one – can just connect ‘gas surface tension’ into the ‘volume velocity’ input on the flipsolver node and put vel, surface, and collision into the fields.

–still trying to figure out viscosity via the Gas SPH Forces… but I think it will require a bit more setup to get the data applied in the right places.
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Solitude

–still trying to figure out viscosity via the Gas SPH Forces… but I think it will require a bit more setup to get the data applied in the right places.

Can't you just plug Gas Blur or Gas Diffuse DOP into Volume Velocity input to blur vel field and tweak the parameters to?
Tomas Slancik
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The gas surface tension microsolver works a treat ;¬) Using the gas blur however doesnt really work as viscosity effect, as it messes with velocity as whole, i.e the effect of gravity etc is also dampened. Viscosity is more of an internal fluid friction/dampening. Not quite sure how we can get that to work.
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Nick
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hey niko, where are you plugging in the gas suface tension dop? I've tried putting it into a few different places in the dop network, but nothing is affecting the solve.

here's a hip file I've been starting from

Attachments:
flip_visc.hipnc (370.9 KB)

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hi goldleaf
Ive plugged it into the third input “volumeVelocity” on the flip solver it self.
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Nick
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hmm…. I've got it plugged in there, but I'm not getting any changes to the sim. What do you have in the Velocity/Surface/Collision field parameters? Was you tension set really high?

**EDIT**

Nevermid, I forgot I hadn't looked at the included example file for the gas surface tension dop. It shows you need to have vel, surface, collision, respectively in the three fields I asked about.

thanks again!
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