How to solve using relaxation techniques

dmoroian · February 10, 2009, 09:43

Hello Vishal,
Is there any chance that you have opened this file with a windows editor? If so, try to do a "dos2unix" on it.

For the rest of the forum: can anyone tell me how it sould be discretized the following scalar equation?

where a, b, and c are scalars.
It seems that

fvScalarMatrix Eqn1(
fvm::div(a*fvc::grad(b)+a*b*fvc::grad(c))
);

is not an acceptable syntax.

Dragos

dmoroian · February 10, 2009, 09:46

Hello Vishal,
Is there any chance that you have opened this file with a windows editor? If so, try to do a "dos2unix" on it.

For the rest of the forum: can anyone tell me how it sould be discretized the following scalar equation?

where a, b, and c are scalars.
It seems that

fvScalarMatrix Eqn1(
fvm::div(a*fvc::grad(b)+a*b*fvc::grad(c))
);

is not an acceptable syntax.

Dragos

nandiganavishal · February 10, 2009, 13:39

Hi Dragos,

I am running OpenFOAM on a Linux (ubuntu) machine... I am not using windows...

Thanks

Regards

Vishal

nandiganavishal · February 26, 2009, 14:01

Hi All,

As I had already posted before.. I would like to know more about how exactly PhiEqn.relax() and Phi.relax works. I know former is implicit and it relaxes the matrix and the latter just does it explicitly..but how exactly these are done in openfoam... .What is the advantage of one over the other and hown exactly one should choose between them??

Kindly offer your suggestions..

nandiganavishal · February 26, 2009, 14:02

Hi All,

As I had already posted before.. I would like to know more about how exactly PhiEqn.relax() and Phi.relax works. I know former is implicit and it relaxes the matrix and the latter just does it explicitly..but how exactly these are done in openfoam... .What is the advantage of one over the other and hown exactly one should choose between them??

Kindly offer your suggestions..

Regards

Vishal

nimasam · May 26, 2010, 02:10

hi dear openFoam former
im going to solve a linear equation set in openFoam
AB=C ( A ,C are vectors and B is a tensor )
how can i manage this structure in openFoam? , i would like to use openFoam iterative solver directly

actually i have two vectors (A,C) and i'd like to find transformation tensor (B)
any help?

February 10, 2009, 09:43	Hello Vishal, Is there any ch	#21
dmoroian Senior Member Dragos Join Date: Mar 2009 Posts: 648 Rep Power: 20	Hello Vishal, Is there any chance that you have opened this file with a windows editor? If so, try to do a "dos2unix" on it. For the rest of the forum: can anyone tell me how it sould be discretized the following scalar equation? where a, b, and c are scalars. It seems that fvScalarMatrix Eqn1( fvm::div(afvc::grad(b)+ab*fvc::grad(c)) ); is not an acceptable syntax. Dragos

February 10, 2009, 09:46	Hello Vishal, Is there any ch	#22
dmoroian Senior Member Dragos Join Date: Mar 2009 Posts: 648 Rep Power: 20	Hello Vishal, Is there any chance that you have opened this file with a windows editor? If so, try to do a "dos2unix" on it. For the rest of the forum: can anyone tell me how it sould be discretized the following scalar equation? where a, b, and c are scalars. It seems that fvScalarMatrix Eqn1( fvm::div(afvc::grad(b)+ab*fvc::grad(c)) ); is not an acceptable syntax. Dragos

February 10, 2009, 13:39	Hi Dragos, I am running Ope	#23
nandiganavishal Senior Member Vishal Nandigana Join Date: Mar 2009 Location: Champaign, Illinois, U.S.A Posts: 208 Rep Power: 18	Hi Dragos, I am running OpenFOAM on a Linux (ubuntu) machine... I am not using windows... Thanks Regards Vishal

February 26, 2009, 14:01	Hi All, As I had already po	#24
nandiganavishal Senior Member Vishal Nandigana Join Date: Mar 2009 Location: Champaign, Illinois, U.S.A Posts: 208 Rep Power: 18	Hi All, As I had already posted before.. I would like to know more about how exactly PhiEqn.relax() and Phi.relax works. I know former is implicit and it relaxes the matrix and the latter just does it explicitly..but how exactly these are done in openfoam... .What is the advantage of one over the other and hown exactly one should choose between them?? Kindly offer your suggestions..

February 26, 2009, 14:02	Hi All, As I had already po	#25
nandiganavishal Senior Member Vishal Nandigana Join Date: Mar 2009 Location: Champaign, Illinois, U.S.A Posts: 208 Rep Power: 18	Hi All, As I had already posted before.. I would like to know more about how exactly PhiEqn.relax() and Phi.relax works. I know former is implicit and it relaxes the matrix and the latter just does it explicitly..but how exactly these are done in openfoam... .What is the advantage of one over the other and hown exactly one should choose between them?? Kindly offer your suggestions.. Regards Vishal

May 26, 2010, 02:10	a linear equation	#26
nimasam Senior Member Nima Samkhaniani Join Date: Sep 2009 Location: Tehran, Iran Posts: 1,266 Blog Entries: 1 Rep Power: 24	hi dear openFoam former im going to solve a linear equation set in openFoam AB=C ( A ,C are vectors and B is a tensor ) how can i manage this structure in openFoam? , i would like to use openFoam iterative solver directly actually i have two vectors (A,C) and i'd like to find transformation tensor (B) any help?

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