I am a newbie in ANSYS and I have a doubt about the Jacobian Matrix and the strain and stress tensors used in the USERMAT routine.
In the numerical approximation of the Jacobian Matrix, the incremental strain that I have to use is a increment in the logarithmic strain tensor or in the right cauchy green tensor?
And... the increment in the stress tensor is a increment in the Kirchhoff stress tensor or in the Cauchy stress tensor?
I have developed a variational constitutive model and I would like to implement it in ANSYS. Anyone can help me?