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How To Modify the eqution

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Old   March 26, 2008, 00:39
Default Hi,everyone! I want to add the
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yinyajun
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Hi,everyone! I want to add the V * dT/dx to the laplacian slover. And the V is the const value in the x direction. Thank you for hint .It is very good if there is a similar example.
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Old   March 31, 2008, 17:01
Default Setting a constant in the code
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David P. Schmidt
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Setting a constant in the code:

const dimensionedScalar hconst
(
"hconst",
dimensionSet(0, 2, -2, 0, 0, 0, 0),
800.0e3
);

Reading a constant from an input file, which is usually a better idea is easy. Just check out readTransportProperties.H for any of the CFD codes.

fvc::grad(T) would give you the gradient of T. You can dot this with a unit vector in the x direction. Set the constant vector xhat, similar to the scalar example above and do the dot product using the & operator. There might be a method of taking just the x component if you dig through the vector class, but I don't know off the top of my head.

-DPS
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