2 replies to this topic

[hazmee]

i have a problem in covnverging the high pressure stripper (in hysys case, i use absorber) so. the message appear when i try to run the column "fatal error - zero diagonal....'


so.. what should i do to converge it..
here is attached the work dat i've done.

and i'm using hysys v 3.2. (older version)

[Padmakar Katre]

i have a problem in covnverging the high pressure stripper (in hysys case, i use absorber) so. the message appear when i try to run the column "fatal error - zero diagonal....'


so.. what should i do to converge it..
here is attached the work dat i've done.

and i'm using hysys v 3.2. (older version)

Dear,
Where is the attachment? And tell me us the detailed background of your simulation?

[joerd]

You usually get that message when the vapor or the liquid flow becomes zero on one or more trays. Check all your inputs, feed streams etc. and your specs first. See if you can use damping to avoid oscillations while converging. Try another solver method. Try different specs, if you can. Improve your initial estimates, especially the temperature profile.
If you tried all this, and still have problems, post your case here and we'll see if we can help you out.