# Rain Droplets on Leaf--Realistic Water Behavior

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Hey all,

Im trying to  generate an accurate representation of rain drops interacting with a leaf.  I understand it is challenging and multistep process, so I will try to make my questions precise and limited here as I go through this.

Ive noticed that in this real world scenario (see links), parts of the water droplets bounce with great force off of the leaf, reforming spherical shapes, while the other portions of the water, via adhesion forces, forms pools along the leaf.

https://www.shutterstock.com/video/clip-1012286918-slow-motion-close-up-macro-dof-big

Ive seen a lot of excellent showcases of waters physical properties--namely  adhesion and cohesion forces, using both flip and pop fluids.  I have some very  rudimentary stuff working for this based on other peoples workflows.

However, im personally struggling with this initial collision condition where the water droplets either:
1)  literally bounce off the surface and reform spherical shapes (cohesion).
or:
2) form flat high motion pools along the leaf (adhesion).

This seems very promising to me:

I can see  clearly that his work satisfies this condition, provided he provides the water an upwards velocity force to satisfy the initial state.  But the scenario here is a bit different here, Im dropping a spherical fluid source onto an object.  The results I am getting have  very little 'splash' of any kind.  It just seems like the fluid is colliding with an infinitely smooth surface.  Ive tried to turn on bounce in both the static object and the flip fluid (though it defines this 'bounce' as elasticity which seems to be a different property).  I get particles that explode out from the surface, but the overall affect seems 'faked', like the water is detonating directly up, not that it is being busted apart.  If I turn surface tension up high enough I can get it reform angry wobbly spheres (lolz), but then the particles on the surface itself dont behave accurately.........

Im kind of stuck in this odd place where im not sure if I need to experiment with costume force based on proximity, collision point, etc, or if I need to rethink my process altogether.

Any tips would be appreciated!

Im currently using flip, dropping it onto a plane.  Ive got some adhesion and cohesion forces working alongside a pop fluid node.  I dont have my head fully wrapped around anything just yet, but ive provided my file.

Thanks!!!

RAIN_DROP_PRACTICE_C_v001_UPL.hipnc

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