Two questions about archived thread727-53543:
1. GSC ended the thread by saying, "Setting linear or piecewise linear elastic properties with poisson ratio > 0.495 could give fairly good results at small deformations only." I would think that using a Poisson's ratio >= 0.49, even for small strains, leads to serious numerical errors ( p. 42). Has anyone besides GSC obtained reasonable FEA results for nearly incompressible materials by using a Poisson's ratio and bulk modulus (instead of Young's modulus) from small-strain linear elasticity theory?
2. Earlier in the thread (5 jun 03) jgough said, "In this case his uniaxial tension test should suffice to provide a value for C10. Theoretically it shouldn't matter what deformation mode he uses (as long as his material is isotropic, which it should be)...." Since rubber's stress-strain curve is very different for compression than tension, why shouldn't the deformation mode of the uniaxial test matter when determining constants for a hyperelastic material model?
1. GSC ended the thread by saying, "Setting linear or piecewise linear elastic properties with poisson ratio > 0.495 could give fairly good results at small deformations only." I would think that using a Poisson's ratio >= 0.49, even for small strains, leads to serious numerical errors ( p. 42). Has anyone besides GSC obtained reasonable FEA results for nearly incompressible materials by using a Poisson's ratio and bulk modulus (instead of Young's modulus) from small-strain linear elasticity theory?
2. Earlier in the thread (5 jun 03) jgough said, "In this case his uniaxial tension test should suffice to provide a value for C10. Theoretically it shouldn't matter what deformation mode he uses (as long as his material is isotropic, which it should be)...." Since rubber's stress-strain curve is very different for compression than tension, why shouldn't the deformation mode of the uniaxial test matter when determining constants for a hyperelastic material model?
