• Carl
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  • Registered: 10-09-2009
  • Posts: 22

Topic: NRSolver

Hi!

I am currently working on a multiscale project and need to implement a nonlinear solver in both my macro and micro scale problems. I was thinking of using a Newton-Raphson iterative solver. I found that it was already implemented in nrsolver and nrsolver2. The question is: Which one should I use? In the file nrsolver.h it says that it is experimental while in nrsolver2.h it says that I should use nrsolver... A bit confusing :-)

/Carl

2 Reply by bp

  • bp
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  • From: Prague, Czech Rep.
  • Registered: 02-03-2007
  • Posts: 1,047

Re: NRSolver

Hi Carl,

use nrsolver.h as this is the one which has been used in many nonlinear static simulations for a long time, seems to be working well and thus is no longer experimental. The reason for these two solvers is historical: initially it was not possible to combine arc-length and classical Newton-Raphson solver in one analysis, later the Newton-Raphson implementation was extended to allow this. The old implementation is in nrsolver2, while the new one in nrsolver.

I will change the description. Thank you.

Borek

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