Jump to content
Geochemist's Workbench Support Forum

Newton-Raphson did not converge after 999 iterations


Frank Bok

Recommended Posts

Hello,

I have prepared a database (attached) and both TEdit and React are loading the file without any warning. But even the simplest calculations fail and give an error message like this:

Quote

Solving for initial system.

 Loaded:    5 aqueous species,
            0 minerals,
            0 gases,
            0 surface species,
            4 elements,
            0 oxides.

Newton-Raphson did not converge after 999 iterations, maximum residual =           1, Xi = 0.0000
Largest residual(s):
                       Resid     Resid/Totmol   Cbasis
---------------------------------------------------------
 Cl-                1.007e+200            1   3.406e-109
 Na+                2.007e+200            1   6.813e-109
---------------------------------------------------------

Is there a way to locate the error to make it work?

Thank you in advance and best regards,
Frank

thermo_test.tdat

Test.rea

Link to comment
Share on other sites

Hi Frank,

The biggest problem is that you’re missing values for Bdot and the water activity coefficient terms in the Tables section of your thermo dataset. You’ll probably also want to set real values  for the ion size parameter for the basis and aqueous species, since 500 is currently being used.

For more information, please see the Thermo Datasets chapter of the GWB Reference Manual.

Regards,

Brian Farrell
Aqueous Solutions LLC
 

Link to comment
Share on other sites

Hi Brian,

thank you for the information. Acutally I wanted to use the activity model "phreeqc" so this is one of the reasons I got in this trouble. I should more often remember to "RTFM"... ;-)

Thank you and best wishes!

Frank

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...