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Flyaway particles in viscous FLIP


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I'm running a FLIP sim that I would like to make fairly viscous (read: blood from a wound). If I crank the viscosity high (2500 - 5000) I can see some general slowdown, but the problem is I still get lots of little flyaway particles and after meshing the result still looks very particle-y. I've toyed with surface tension, but have found that it either makes no apparent difference or it just makes the sim explode. Any idea on how I can make my viscous fluid more "stringy"/viscous? The emitter is very small as the scene is fairly small--I actually had to scale up the imported alembics so that the character's head is about a meter high, as "real life" size was too tiny for me to get anything useful out of FLIP. I'm testing at a particle separation of 0.002, doing more detailed tests at 0.0005. Could it just be a matter of cranking those down to ridiculous sim times for it to look less like popcorn? (Unfortunately posting the file isn't do-able, any more info needed I'm happy to supply.)

Boosting reseeding to oversampling 48/bandwidth 3 seems to help with the overall feel, but just delays the flyaways, doesn't eliminate them.

Thanks for any help! 

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Hey @bentway23 you shouldn't need to crank the particle separation that much.

Try to have the scene scale to correct scale or slightly bigger (blood wound maybe make it half a meter or 0.5 houdini unit)

To make it more stringy try to increase the density on the physical tab of the flip object to maybe 2500 or so.

Try to use a bit of viscosity and some surface tension but those parms shouldn't need to go crazy high.

But the main thing is to have some very good velocity to have a nice burst so it doesn't explode but it makes some interesting shapes

Something like this for the velocity

If you can post a sample scene (not the one u r working with) I can debug it for u



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I had heard that there were gods, wise and benevolent, who walk the earth and visit the forums to ease the troubles of mankind. I was dubious once; now, no longer, for you are obviously such a god.

That was perfect. I reduced my viscosity from 2500 to 5, boosted the density to about 5K, and it's exactly what I was looking for! I had been varying the velocity of the emitters, and now they're not just making particles fly away, but rather making interesting, gooey shapes. Thanks so much!

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