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Meaning of 'bounded' keyword in fvSchemes.

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Old   May 19, 2014, 12:12
Default Meaning of 'bounded' keyword in fvSchemes.
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Canakkale Dardanelspor
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Hi,

== 1 ==
Could someone please explain what the main difference of using "bounded" keyword result in?

Code:
divSchemes {
...
    div(phi,U)      bounded Gauss linearUpwind grad(U);
...
}
Code:
divSchemes {
...
    div(phi,U)      Gauss linearUpwind grad(U);
...
}
== 2 ==
In Table 4.10 of http://www.openfoam.org/docs/user/fvSchemes.php, it is stated that 'linearUpwind' is 'bounded'. Despite this, why do we need to add 'bounded' keyword to the scheme arguments?

==3==
Many thanks in advance.
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Old   May 19, 2014, 12:20
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==1==
My understanding based on the tutorial cases in OF 2.2.x, 'bounded' keyword is only added when the corresponding simulation is 'steadyState'.

==2==
Even if so, the main reason is absent for myself.
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Old   June 1, 2014, 17:57
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Hi,

The following clearly explains 'bounded' keyword's meaning:

http://www.openfoam.org/version2.2.0/numerics.php
emjay, reza2031, nanavati and 4 others like this.
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Old   June 2, 2014, 02:16
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T. Chourushi
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Good Question

As stated on the link:

Quote:
In particular, for steady-state it is necessary to use the bounded form, equivalent to fvm::div(phi, h) - fvm::Sp(fvc::div(phi), h). For transient solutions, it is usually better to implement only the fvm::div(phi, h) term.
I have few difficulties:
(1) From where this reference is taken?
(2) What if Source is zero? Then, what it is the significance of the "bounded" term?

Any better explanation for these with reference (in relation to papers or books)?
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Old   August 22, 2014, 09:07
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Pratik Nanavati
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Agree with Tushar,

On the Given link they have explained, but its on quite High Note for the beginners.
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