Bob:

Thanks for the input. I was able to eliminate the small flutter, and am pretty well convinced I have a 'good' model. After studying the results, everything seems to be working very nicely--no anomolies whatsoever. Sorry, but I didn't keep track of the number of iterations during the trials, but playing around with ITMAX seemed to make no difference. I tried dropping ITMAX as low as 10 for several runs, but ultimately it was SURTOL that allowed me to more or less dial in the continuity error.

I have seen in many large models that when lots of nodes go into surcharge, things can get numerically whacky, particulalry if the surcharged nodes are widely dispersed (separated by lots of non-surcharged nodes) throughout the model.

Thanks again for the help.
John Paine
John_Paine@URSCORP.COM