# How to set coefficient of rolling friction

Hello,
According to Rodaina Aboul Hosn(2017)[1],we can introduce rolling resistance by the rolling stiffness and coefficient of rolling friction.According [2],I use Law2_ScGeom6D_CohFrictPhys_CohesionMoment().I find the rolling stiffness alphaKr[3], but I don't find the coefficient of rolling friction.How can I set coefficient of rolling friction?

In addition, rolling stiffnesses are proportional to the shear stiffness through dimensionless factors alphaKr[3]. I think the shear stiffness is calculated using Young's modulus,right?

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Luc Sibille
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2019-10-21
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2019-10-21
2019-10-21
 Luc Sibille (luc-sibille) said on 2019-10-21: #1

Hello,

Here is the rolling friction coefficient:
etaRoll

Yes the shear stiffness is calculated using the parameter
young
which actually not a Young modulus, but a stiffness modulus of the
particles.

Finally you can find a new paper about theses questions in the
continuity of the one from Aboul Hosn et al, here [1]

Best,
Luc

Le 21/10/2019 à 14:17, Chu a écrit :
> New question #685303 on Yade:
>
> Hello,
> According to Rodaina Aboul Hosn(2017)[1],we can introduce rolling resistance by the rolling stiffness and coefficient of rolling friction.According [2],I use Law2_ScGeom6D_CohFrictPhys_CohesionMoment().I find the rolling stiffness alphaKr[3], but I don't find the coefficient of rolling friction.How can I set coefficient of rolling friction?
>
> In addition, rolling stiffnesses are proportional to the shear stiffness through dimensionless factors alphaKr[3]. I think the shear stiffness is calculated using Young's modulus,right?
>
> Thanks for your any suggestion.
>
>

--
Luc Sibille
Université Grenoble Alpes / IUT1 de Grenoble
Laboratoire 3SR: Sols, Solides, Structures, Risques

Tel lab.: +33 (0)4 76 82 63 48
Tel IUT: +33 (0)4 76 82 53 36

 Bruno Chareyre (bruno-chareyre) said on 2019-10-21: #2

Hi,
Rolling friction is listed just a couple lines below [3].

> I think the shear stiffness is calculated using Young's modulus,right?

Yes. Overall there is only one dimensional stiffness (Young), used to define normal stiffness, the others are defined relatively, by a set of dimensionless coefficients.

Bruno

 Chu (arcoubuntu) said on 2019-10-21: #3

Thanks Luc Sibille, that solved my question.

 Chu (arcoubuntu) said on 2019-10-21: #4

Thanks Bruno, that solved my question.

 manisharma (manisharma11211) said on 2019-10-21: #5

Thanks for this information. It useful