[Trilinos-Users] NOx-LOCA issue with convergence - Arc length continuation

[narendiran kumar]

hi,

I am using nox package for solving vector problem (nof. eqn 200) using
arc-length continuation.  I have modified chancontinuation example program
and i gave initial guess in vector form (for n = 200 eqn).  When i was
compile, i am getting warring.  I guess it's because of initial guess.  Can
anyone please help me.

thanks in advance,

Regards,
K. Narendiran


Example warring o/p:

************************************************
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Start of Continuation Step 11 : Parameter: Da = 8.747e-01 from 9.511e-01
Continuation Method: Arc Length
Current step size  = 8.434e-05   Previous step size = 5.812e-05
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Warning: NOX::Solver::LineSearchBased::init() - The solution passed into the
solver (either through constructor or reset method) is already converged!
The solver wil not attempt to solve this system since status is flagged as
converged.

************************************************************************
-- Nonlinear Solver Step 0 --
||F|| = 8.598e+00  step = 0.000e+00  dx = 0.000e+00 (Converged!)
************************************************************************

************************************************************************
-- Final Status Test Results --
Converged....OR Combination ->
  Converged....F-Norm = 6.065e-01 < 1.000e+00
               (Length-Scaled Two-Norm, Absolute Tolerance)
  ??...........Number of Iterations = -1 < 20
************************************************************************

************************************************************************
-- Nonlinear Solver Step 0 --
||F|| = 8.598e+00  step = 0.000e+00  dx = 0.000e+00 (Converged!)
************************************************************************

************************************************************************
-- Final Status Test Results --
Converged....OR Combination ->
  Converged....F-Norm = 6.065e-01 < 1.000e+00
               (Length-Scaled Two-Norm, Absolute Tolerance)
  ??...........Number of Iterations = -1 < 20
************************************************************************

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
End of Continuation Step 11 : Parameter: Da = 8.747e-01 from 9.511e-01
--> Step Converged in 0 Nonlinear Solver Iterations!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


    Calling Predictor with method: Secant

    ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    Arc-length scaling calculation for parameter Da:
    Parameter component of predictor before rescaling = 9.058e+02
    Scale factor from previous step 1.000e-03
    Parameter contribution to arc-length equation     = 9.058e-01

    Parameter component of predictor after rescaling  = 9.058e+02
    New scale factor (theta)                          = 1.000e-03
    Parameter contribution to arc-length equation     = 9.058e-01
    ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
At parameter value: 0.87472249   the solution vector (norm=0.0096190908) is
 0.00045035754 0.0011253381 0.00036360756 0.00090869718 0.000277962
0.00069468095 ... 0.0053114264 0.00023180336

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


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