Fluid particles falling through rigid body object

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Hi, this should be a fairly easy one, i´m just starting out, but could not get my head around it.

i modeled a simple geometry in Cinema 4d, exported it to Houdini.
Then i turned it into a rigid body object.
after that i created a grid, that i assigned emit particle fluid to.

The problem is, that the particles are falling through, i tried the same thing with some primitive objs and it worked. What´s strange is that it falls through, but there is some collision inside the model happening.

I guess it has to do with how Houdini is interpreting my mesh or its collision.

any ideas, what could be the problem?
thank you for your support.

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rigid_body_fluid_problem.png (962.4 KB)

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If you go into the autodopnetwork for your simulation and click the geometry node in there, and then under collisions, I forget if its bullet or RBD, but if you check ‘show collision geometry’ and tamper with the settings you can see how your mesh is working. Put wireframe on to see clearly. Changing to concave, or upping the uniform divisions will be what you're after I think.
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Also your geometrz is not exactly a good choice.

Probablz take a look at this tutorial:
It will give you all to get you started!

https://www.sidefx.com/index.php?option=com_content&task=view&id=2157&Itemid=262 [sidefx.com]
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Hi ispep,

thank you, for your comment, but unfortunately i could not find a proper geometry node in the autodopnetwork:

here´s a screenshot, which one would it be?
It seems that my waterfall is not properly connected to the rest, should there be some kind or merge node?

@baldwithglasses

i´m following exactly that tutorial, but i wanted to create my own geometry.

i just imported a simple base mesh which should turn into a more complete one,
It´s more or less a prove of concept, i will refine it, once it´s working…. (screenshot attached….)

thank you!

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Screen Shot 2015-12-14 at 22.50.16.png (461.2 KB)
Screen Shot 2015-12-14 at 22.57.00.png (122.8 KB)
Screen Shot 2015-12-14 at 22.55.26.png (157.3 KB)

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maybe try putting a reverse sop on your geometry before sending it to dops…houdinis winding order is reversed from most other modelling packages
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Hey there, okay perfect!

If you take a look at the geometry they are using, you will see it is rather “closed” at all times, as it is just some extruded stuff.
Your Mesh has a lot of very thin areas. As Houdini will built a volumetric prepresentation of your mesh, thin areas in the mesh will lead to particles leaking aka not colliding. You can get rind of that by increasing the resolution, but probably not useful for an initial test.

Also the Houdini DOP Net View you posted. Is this your setup?
If so, its is wired up wrong.
The FLip Object need to go in the Flipsolver on the left input.
And the Static Solver need to go in Merge 1.
You also can't Loop stuff like you did between Merge1 and the solver.

Hope this helps
Cheers!
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Hi thanks a lot for both of your tips, i´m gonna look into it.

An yes that´s how it was set automatically, after i did the following steps.

-import model
-create plane
-set model to static object
-set plane as fluid emitter

i did not change anything, this is just, how it was built automatically.

thank you
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Hmm… okay..

Not sure if stuff changed here in H15, I'm still on Houdini 14 and from that perspective it looks like wrong wiring? Maybe a bug?
Cant tell…
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