> > Precisely, the effective mass (for a given contact) is not computed in > SimpleViscoelasticRelationships. So cn can be larger than the critical > value for this contact. You agree? >From this equation
> m_eff * dn'' + cn * dn' + kn * dn = 0 we have tc and en: (*) tc = pi 2 m_eff / sqrt( 4 kn m_eff - cn^2 ) (note your delta in brackets) en = exp( -cn tc / 2 / meff ) where we have kn and cn: kn = m_eff / tc^2 * ( pi^2 + ln^2(en) ) cn = -2 * m_eff / tc * ln(en) Then, for pair spheres with mass m1 we have m1_eff = m1/2, en1, tc1 => kn1 and cn1. For pair spheres with mass m2 we have m2_eff = m2/2, en2, tc2 => kn2 and cn2. For pair spheres with mass m1 and m2 we have 1) 1/m12_eff = 1/m1+1/m2, en12, tc12 => kn12, cn12, OR we have 2) 1/kn12 = 1/kn1 + 1/kn2 and 1/cn12 = 1/cn1 + 1/cn2. >From (*) cn^2 can't be more than cn_crit^2 = (4 kn m_eff)... _______________________________________________ Mailing list: https://launchpad.net/~yade-dev Post to : [email protected] Unsubscribe : https://launchpad.net/~yade-dev More help : https://help.launchpad.net/ListHelp _______________________________________________ yade-dev mailing list [email protected] https://lists.berlios.de/mailman/listinfo/yade-dev
