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Jacobian of NS equation

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Old   May 18, 2013, 18:57
Default Jacobian of NS equation
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Mojtaba Moshiri
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Dear SU2 developers

My question is about the projected Jacobian of NS equation as is calculated in function "CNumerics::GetViscProjJacs" I derived the very same expressions except from the length of edge vector in the denominator of all elements of Jacobian matrix. Could you please explain where this term came from?

I wonder if it is possible to have some more detailed references about the formulation used in different parts of the code other than what is cited in the website and the paper AIAA 2013-0287.
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Old   May 27, 2013, 21:28
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Francisco Palacios
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Quote:
Originally Posted by Mojtaba M View Post
Dear SU2 developers

My question is about the projected Jacobian of NS equation as is calculated in function "CNumerics::GetViscProjJacs" I derived the very same expressions except from the length of edge vector in the denominator of all elements of Jacobian matrix. Could you please explain where this term came from?

I wonder if it is possible to have some more detailed references about the formulation used in different parts of the code other than what is cited in the website and the paper AIAA 2013-0287.
Hi,

The length of the edge is a key element that you obtain when you estimate the normal gradient as $\partial_n U = (U_i - U_j) / (x_i - x_j)$. This simplification is used to evaluate the first order Jacobian (instead of Green-Gauss or LS).

Cheers,
Francisco
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