unsymmetric jacobian storage and calculation in Abaqus

[fab69]

I m actually dealing with full thermo-mechanical coupling and the problem is that, when this situation comes up, you have to deal with an unsymmetric jacobian storage and calculation.
You can find a description of this kind of problem in Abaqus user's manual, volume1, section 6.5.4 where it is written :
" Solving this system of equations requires the use of the unsymmetric matrix storage and solution scheme"
But there is no description about those schemes...
If anyone knows, feel free to tell me

Thx

 

[jorgenb]

ABAQUS will solve problems that have an unsymmetric Jacobian, you just need to specify the unsym parameter.

If you are writing a UMAT subroutine, then you simply need to calculate the true unsymmetric Jacobian and return that matrix back to ABAQUS.

Jorgen

(polymerFEM.com)
Information about advanced FEM of polymers.