Why solving

kar · April 26, 2008, 13:46

Hi,
one thing I've noticed in my own and icoFoam solver too (for you to show it's not really specific): solve until reach stationary solution (iteration count 0), start solving again with obtained solution and iterations for U jump to 4, but for p to 150.
So there must be some deficiency of previous timestep values or similar... Can you explain more precisely reasons why solving starts again?

K.

kar · April 28, 2008, 11:52

Looks like it was simply insufficient precision for saved solution (too little digits).

kar · April 30, 2008, 15:15

But that is not all.
Only if solved phi surface field is read in at the beginning, there follows no iterating...
The cause is, that phi is not equal to mesh.Sf() & fvc::interpolate(U).
Should not be like that, right? That happens in cavity at Re=1000, only linear (unbounded) schemes used.
Could you, please, explain this problem?

April 26, 2008, 13:46	Hi, one thing I've noticed in	#1
kar Senior Member Kārlis Repsons Join Date: Mar 2009 Location: Latvia Posts: 111 Rep Power: 17	Hi, one thing I've noticed in my own and icoFoam solver too (for you to show it's not really specific): solve until reach stationary solution (iteration count 0), start solving again with obtained solution and iterations for U jump to 4, but for p to 150. So there must be some deficiency of previous timestep values or similar... Can you explain more precisely reasons why solving starts again? K.

April 28, 2008, 11:52	Looks like it was simply insuf	#2
kar Senior Member Kārlis Repsons Join Date: Mar 2009 Location: Latvia Posts: 111 Rep Power: 17	Looks like it was simply insufficient precision for saved solution (too little digits).

April 30, 2008, 15:15	But that is not all. Only if	#3
kar Senior Member Kārlis Repsons Join Date: Mar 2009 Location: Latvia Posts: 111 Rep Power: 17	But that is not all. Only if solved phi surface field is read in at the beginning, there follows no iterating... The cause is, that phi is not equal to mesh.Sf() & fvc::interpolate(U). Should not be like that, right? That happens in cavity at Re=1000, only linear (unbounded) schemes used. Could you, please, explain this problem?

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