yade-users team mailing list archive

[Jan Stránský <question252675@xxxxxxxxxxxxxxxxxxxxx>]

Question #252675 on Yade changed:
https://answers.launchpad.net/yade/+question/252675

Jan Stránský proposed the following answer:
Hi,

@Janek: sorry to disagree. When a bond is stretched, it stores some
potential energy. When the bond is then broken suddenly, this potential
energy is "lost" (dissipated) and in no way "goes to the kinetic energy and
potential energy in other springs".

@Pascal: O.energy.total() just sums all stored energies in O.energy. I
don't have much experience, but I would say it is not 100% safe approach to
rely on this value, e.g. damping in NewtonIntegrator is not tracked and
external work is tracked only indirectly (actually as the change of total
energy :-). Anyway, you can try it yourself on a simple simulation (few
spheres with defined bond breaking).

Accorging to the documentation
of Law2_ScGeom6D_CohFrictPhys_CohesionMoment, energy dissipated from bond
breaking cannot be tracked. But it should not be difficult to implement it.

cheers
Jan



2014-08-06 10:13 GMT+02:00 Janek Kozicki <
question252675@xxxxxxxxxxxxxxxxxxxxx>:

> Question #252675 on Yade changed:
> https://answers.launchpad.net/yade/+question/252675
>
>     Status: Open => Answered
>
> Janek Kozicki proposed the following answer:
> when bond breaks energy goes to the kinetic energy and potential
> energy in other springs. Both are tracked.
>
>
> Pascal Hagenmuller said:     (by the date of Tue, 05 Aug 2014 20:41:42
> -0000)
>
> > New question #252675 on Yade:
> > https://answers.launchpad.net/yade/+question/252675
> >
> > Hello,
> >
> > I am working with clumps composed of spheres. The sphere-sphere contacts
> are cohesive and implemented through the law
> Law2_ScGeom6D_CohFrictPhys_CohesionMoment. All contacts are initially
> cohesive and once broken they remain broken.  The breaking of bonds
> dissipates energy (the energy stored in the elastic spring which breaks).
> >
> > Similarly to the tracking of plastic dissipation
> (O.energy['shearDissip']), is it possible to track the dissipation because
> of bond breaking or is it already tracked somewhere ? If not can I rely on
> O.energy.total() to calculate the bond breaking dissipation as the
> difference between the total energy computed by Yade and the work of
> external force imposed to the system ?
> >
> > Thanks
> >
> > Pascal
> >
> > --
> > You received this question notification because you are a member of
> > yade-users, which is an answer contact for Yade.
> >
> > _______________________________________________
> > Mailing list: https://launchpad.net/~yade-users
> > Post to     : yade-users@xxxxxxxxxxxxxxxxxxx
> > Unsubscribe : https://launchpad.net/~yade-users
> > More help   : https://help.launchpad.net/ListHelp
> >
>
>
> --
> Janek Kozicki                               http://janek.kozicki.pl/  |
>
> You received this question notification because you are a member of
> yade-users, which is an answer contact for Yade.
>
> _______________________________________________
> Mailing list: https://launchpad.net/~yade-users
> Post to     : yade-users@xxxxxxxxxxxxxxxxxxx
> Unsubscribe : https://launchpad.net/~yade-users
> More help   : https://help.launchpad.net/ListHelp
>

-- 
You received this question notification because you are a member of
yade-users, which is an answer contact for Yade.