Le jeudi 31 mai 2007 11:30, Igor Peterlik a écrit : > Dear getfem experts, > > First, thanks for providing such a great FEM code. I found > it really useful for my research. > > And now, the problem. I want to model > a deformation of a silicon cylindric object. According to > real lab measurements, Mooney-Rivlin material with constants > C_10=2.94e+03 and C_01=-1.11e+03 should be suitable for > realistic modelling of the object.
Indeed, i am not an expert in Mooney-Rivlin material constants. It may be understandable that if the constant C_01 is to much negative, the poly-convexity of the law could be lost (but really, I did not study this at all). Are you sure the values you obtained are in an acceptable range ? The constants in the Getfem brick are defined as follows (strain energy) : W = C_01 ( I_1(C) - 3) + C_10 (I_2(C) - 3) where $C = (\nabla \phi)^T \nabla \phi$ is the right Cauchy Green tensor and I_1, I_2 the two first usual invariants. Is it the definition you expected ? Yves. ------------------------------------------------------------------------- Yves Renard ([EMAIL PROTECTED]) tel : (33) 04.72.43.80.11 Pole de Mathematiques, INSA de Lyon fax : (33) 04.72.43.85.29 Institut Camille Jordan - CNRS UMR 5208 20, rue Albert Einstein 69621 Villeurbanne Cedex, FRANCE http://math.univ-lyon1.fr/~renard ------------------------------------------------------------------------- _______________________________________________ Getfem-users mailing list [email protected] https://mail.gna.org/listinfo/getfem-users
