Search
Close this search box.
Hybrid model, UMAT
 
Notifications
Clear all

[Solved] Hybrid model, UMAT

2 Posts
2 Users
0 Reactions
750 Views
Posts: 26
Topic starter
(@sandra)
Eminent Member
Joined: 15 years ago

Hi,

I have written a UMAT for hybrid model (Bergstrom et. al). In the UMAT, I used fourth elastic modulus tensor as jacobian. It seems to create convergence issues right at begining from the first increment. The primary stress equation is (sigma_ij=2mu*epsilon_ij+lamda*epsilon_kk*delta_ij) and I used that expression to compute the jacobian.

Has anyone written a UMAT for this model? All suggestions are welcome.

Thanks

Brunda

Topic Tags
1 Reply
Posts: 3998
(@jorgen)
Member
Joined: 5 years ago

I have coded that model as an Abaqus UMAT. Using a linear elastic Jacobian should be perfectly fine as long as the strains are small.
My guess is that you have some other bug 🙁

-Jorgen

Topic Tags
1 Reply
Share: