KrylovNewton(2)

[mohsenkh]

Dear Vesna

I read this paper, but I didn't understand this following text that explained in this paper:

"when using nonlinear beam elements with fiber cross sections,
it is recommended to begin a simulation with the Newton-
Raphson algorithm, then switch to the Krylov acceleration
algorithm when there are convergence difficulties and return to
Newton-Raphson after a sufficient number of Krylov time steps."

Do I apply this in my model? How can you used this?

Thanks.

[vesna]

Here is the example of what is recommended in the paper:

set tFinal 15.0;
set dt 0.01;
constraints Transformation
numberer RCM
system BandGeneral
test NormDispIncr 1.0e-6 6 2
algorithm Newton
integrator Newmark 0.5 0.25
analysis Transient
set ok 0
set currentTime 0.0
while {$ok == 0 && $currentTime < $tFinal} {
set ok [analyze 1 $dt]
if {$ok != 0} {
test NormDispIncr 1.0e-6 1000 1
algorithm KrylovNewton
set ok [analyze 1 $dt]
test NormDispIncr 1.0e-6 6 2
algorithm Newton
} set currentTime [
getTime]
}