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Initialization using DEFINE_INIT

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Old   February 13, 2012, 22:07
Default Initialization using DEFINE_INIT
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Shashank
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I have a fluid zone and a solid zone in my model. These two zones are connected via a wall. Fluent creates a shadow for the wall when I import the meshed model into it, where shadow faces the fluid zone and the primary wall faces the solid zone.

Now I initialize my velocity and temperature using UDF in solid (only temperature) and fluid zones. But how do I initialize the wall temperature? Can I loop over faces of a thread in a DEFINE-INIT macro?

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Shashank
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Old   February 14, 2012, 01:40
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Variables are stored on cell zones, interior face zones, including coupled wall, do no need predefined conditions.
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Old   February 14, 2012, 01:52
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But the issue is that when I plot "temperature-vs-x" on top wall and its shadow (with node values toggled on), I get three curves. One accessing the value of cell above the wall (in the solid), one using the value of cell below the wall (in the fluid) and the third on between the two (probably on the surface, not sure about this). All I know is that the third one is coming from the corners of the top wall or its shadow.

Could you understand what I just said?
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Old   February 14, 2012, 02:01
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The third one you mentioned is face value and is obtained via interpolation.
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Old   February 14, 2012, 02:07
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Agreed. But what to do if the values are wrong?

My temp profile in solid: Twall + ax + bf(z)

My temp profile in fluid: Twall + ax + cg(z)

My supposed/true temp profile of wall: Twall + ax. But the values of Twall are way off! Maybe because Fluent uses the c0 and c1 values to calculate the values at the centroid of the faces. Right?
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Old   February 14, 2012, 02:08
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FYI: Twall, a, b, c are all constants.
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