Is there any serious drawback when using a NR algorithm with initial stiffness for a dynamic analysis, compared to using NR and revert to NR w/ initial stiffness only upon non-convergence ? It seems that NR w/ initial stiffness always converges in my model, while NR does not.
Is the tangent stiffness matrix updated at the end of each iteration when using NR w/ initial stiffness ? (otherwise it would be exactly the same with modified NR w/ initial stiffness I assume)
Thanks a lot in advance !
Newton-Raphson with initial stiffness
Moderators: silvia, selimgunay, Moderators
Re: Newton-Raphson with initial stiffness
the main drawback is time. from a purely numerical point of view there are situations where it would results in a different answer being found for a given step (you could draw some curves on a sheet of paper and find cases where the two methods will give a different result), you will probably find these do not happen for the typical model.