yade-users team mailing list archive

[Yuxuan Wen <question698173@xxxxxxxxxxxxxxxxxxxxx>]

New question #698173 on Yade:
https://answers.launchpad.net/yade/+question/698173

Hello,

I am thinking of using HertzMindlin or Viscoelastic model for numerical simulation, and I read the source code of both models in advance. And I found that the tangential contact force in both source code is calculated in an incremental way , but the sign of the increments is opposite in these two files. In HertzMinlin course code, the sign of difference is "-", while in the Viscoelastic source code, the sign of difference is "+". I am not very familiar with C++ and I tried my best to understand the meaning behind these two equations, but I am still confused. I wonder if someone who is familiar with these two models can tell me why they are the opposite? Thank you!

In the HertzMindlin source code, the shear force (without the viscous term) is calculated as: 
shearElastic = shearElastic - phys->ks * (incidentVs * dt);
which can be found in line 382 of https://gitlab.com/yade-dev/trunk/-/blob/master/pkg/dem/HertzMindlin.cpp

In the Viscoelastic source code, the shear force (without the viscous term) is calculated as: 
shearForce += phys.ks * dt * shearVelocity;
which can be found in line 125 of https://gitlab.com/yade-dev/trunk/-/blob/master/pkg/dem/ViscoelasticPM.cpp

Best Regards,
Yuxuan Wen

-- 
You received this question notification because your team yade-users is
an answer contact for Yade.