thermal analysis

posted by apalmier on Fri, 30/09/2011 - 13:30

Dear all
I'm trying a thermal analysis in a concrete beam
I write the *.dcf file in the following way
*FILOS
 INITIA
*INPUT
*HEATTR
 BEGIN INITIA
  TEMPER
 END INITIA
 EXECUT SIZES  15(540)
 BEGIN OUTPUT
   FXPLUS
   FILE "TEMPERATURE B0"
   TEMPER
 END OUTPUT
 
It give me a maximum of 5 iteration with a tolerance of convergence equal to 1E-6.
I would like to increase the iteration and increase the tolerance convergence to 1E-3.
someone can help me in this?
Thanks in advance
Apalmier

Forums: 
DIANA

On Mon, 03/10/2011 - 11:25

Hello Apalmier,
For nonlinear temperature analysis use the commands below. You can increase your tolerance convergence using TOLCON. But instead, I suggest you just decrease your timesteps to 5 seconds and increase the number of iterations as shown to 20.
Rgds T.
*HEATTR
BEGIN INITIA
 TEMPER
 NONLIN
END INITIA
 BEGIN EXECUT
   NONLIN  ITERAT  MAXITE 20
   SIZES 15(540)
 END EXECUT
 

By tscullion

On Mon, 03/10/2011 - 17:13

Thanks T.
In this way I increased the iteration... and it work.
Do you know how can I decrease the tolerance convergence. For the moment it converge with a tolerance of 1E-7 I would like to have 1E-3

By apalmier

On Tue, 04/10/2011 - 00:31

 
Hi Ap,
You can use the TOLCON command as shown below. But why do you want to decrease the level of accuracy of your iterative process? The default for DIANA is 1E-6.
Regards T
NONLIN  ITERAT  MAXITE 20
CONVER TEMPER TOLCON=1E-3

By tscullion