simple divergence

sciense · August 18, 2014, 08:12

i have divergence at high Re number in my simple code and it gives negative pressure and unusual osilation
but as i know simple doesnt need turbulent model to converge at high Re !!
how can i over come to this problem
thanks

gafoorcp · August 18, 2014, 16:17

hii....
can you elaborate the details of the problem...
and also one reason for divergence of solution will comes from mesh generation...
regards

Vino · August 19, 2014, 15:14

Hi,

Did you check your solution for low Re? Plz give the details of the simulation you are doing. You can try the simulation with lower cfl no than what you are using already.

sciense · August 24, 2014, 13:31

Quote:

Originally Posted by Vino

Hi,

Did you check your solution for low Re? Plz give the details of the simulation you are doing. You can try the simulation with lower cfl no than what you are using already.

im using patankar's simple method with hybrid scheme and my cfl no is letter than 1
in low Re the converging is very well but in high Re it has a very large divergences and negative results for pressure and velocity

August 18, 2014, 08:12	simple divergence	#1
sciense New Member ali Join Date: May 2014 Posts: 19 Rep Power: 11	i have divergence at high Re number in my simple code and it gives negative pressure and unusual osilation but as i know simple doesnt need turbulent model to converge at high Re !! how can i over come to this problem thanks gafoorcp likes this.

August 18, 2014, 16:17		#2
gafoorcp Member ABDUL GAFOOR CP Join Date: Jul 2014 Posts: 30 Rep Power: 11	hii.... can you elaborate the details of the problem... and also one reason for divergence of solution will comes from mesh generation... regards Vino likes this.

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August 19, 2014, 15:14		#3
Vino Senior Member Vino Join Date: Mar 2013 Posts: 130 Rep Power: 13	Hi, Did you check your solution for low Re? Plz give the details of the simulation you are doing. You can try the simulation with lower cfl no than what you are using already.