yade-dev team mailing list archive

[Bruno Chareyre <bruno.chareyre@xxxxxxxxxxxxxxx>]

On 29/10/14 17:59, Jerome Duriez wrote:
> Inserting the following lines
>             else
>               if (!hertzOn) {
>                 if (!cundallContactPhysics->meniscus)
> scene->interactions->requestErase(interaction);
>               } else {
>                 if (!mindlinContactPhysics->meniscus)
> scene->interactions->requestErase(interaction);
>               }
> between current lines 128-129 would solve this problem.
>
> Agree ?
Nope. The problem if you do that is that you break the fusionDetection
logic.
There is already a requestErase in the right place [1]. The question is
why it is not reached in your case.
The reason is the data files are incomplete, there is no solution found
for the parameters you use in your script (try with
capillaryPressure=30.e3, you will see the difference).
This result is absolutely wrong: there is always a finite volume when
the particles are in contact, mathematicaly speaking. The real problem
is the missing data.
I've put an explicit error message when it occures [3] : the simulation
is wrong, no point continuing.
I think it fixes the bug.

Meanwhile, I fixed another small thing that would give wrong meniscii
during the first iteration. In [2] "D" should not be zero if positive.

Bruno

[1]
https://github.com/yade/trunk/blob/fbd593a9888c11d0ca3dd1d09161f81362433407/pkg/dem/Law2_ScGeom_CapillaryPhys_Capillarity.cpp#L162
[2]
https://github.com/yade/trunk/blob/fbd593a9888c11d0ca3dd1d09161f81362433407/pkg/dem/Law2_ScGeom_CapillaryPhys_Capillarity.cpp#L120
[3]
https://github.com/yade/trunk/commit/85616e85f3dac5b3bb949ba6d7deff0095909f2e


>
> ------------------------------------------------------------------------
> *From:* Yade-dev
> [yade-dev-bounces+jerome.duriez=ucalgary.ca@xxxxxxxxxxxxxxxxxxx] on
> behalf of Bruno Chareyre [bruno.chareyre@xxxxxxxxxxxxxxx]
> *Sent:* October 29, 2014 6:09 AM
> *To:* yade-dev@xxxxxxxxxxxxxxxxxxx
> *Subject:* Re: [Yade-dev] Some cleaning in capillary law
>
>
>> This seems to me contradictory (zero volume meniscii might "form"
>> between contacting spheres depending on the succion) and, associated
>> to the test l.139 [3], it leads, in some cases, to interactions that
>> are never deleted, even if there is no more geometrical overlap
>> neither a meniscus with a non-zero amount of water (because erase on
>> l.160 might be switched).
> I don't see the problem. Can you please show how to get these
> non-erased interactions?
> Cheers.
> Bruno
>
>
>
>
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-- 
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Bruno Chareyre
Associate Professor
ENSE³ - Grenoble INP
Lab. 3SR
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