Problem in collocated grid

verma_rahul · May 22, 2012, 13:37

I am solving unsteady shock tube problem with pressure correction approach. I am solving 2 momentum equation, updated pressure correction equation for compressible case, Energy equation and Equation of state. I used Rhie & Chow formulation for dealing pressure checker boarding problem. I am using SIMPLE.
I have some issues in my code which are following:

My code is working for high relaxation parameter like from 0.5-0.9. But it is not working at low relaxation parameter like less than 0.5??????

Thanks in advance

mb.pejvak · May 22, 2012, 22:33

I recommend you to apply modified Rhie and choe method introduced by Majumdar.
"Role of underrelaxation in momentum interpolation for calculation of flow with nonstaggered grids".

In this method numerical solving is independent of under-relaxation parameter. for me, It worked very well.

May 22, 2012, 13:37	Problem in collocated grid	#1
verma_rahul New Member Rahul Verma Join Date: Jan 2012 Location: Mumbai Posts: 7 Rep Power: 14	I am solving unsteady shock tube problem with pressure correction approach. I am solving 2 momentum equation, updated pressure correction equation for compressible case, Energy equation and Equation of state. I used Rhie & Chow formulation for dealing pressure checker boarding problem. I am using SIMPLE. I have some issues in my code which are following: My code is working for high relaxation parameter like from 0.5-0.9. But it is not working at low relaxation parameter like less than 0.5?????? Thanks in advance

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May 22, 2012, 22:33		#2
mb.pejvak Senior Member Mehdi Babamehdi Join Date: Jan 2011 Posts: 158 Rep Power: 15	I recommend you to apply modified Rhie and choe method introduced by Majumdar. "Role of underrelaxation in momentum interpolation for calculation of flow with nonstaggered grids". In this method numerical solving is independent of under-relaxation parameter. for me, It worked very well.