interchanging face information with cell information/ radiation flux UDF

ximik · May 3, 2011, 20:48

Hello all,

First, I would like to say hello to this community. I have discovered CFD a year or so ago, and believe I truly found my calling. I live for this stuff. I hope to learn much from you all, as well contribute my humble opinions and advice.

For my first question, I hope that someone can help me out with some FLUENT/C programming.

I am writing a UDF (my first one!) that uses the F_SOLAR_SOURCE(f,t), BOUNDARY_RAD_HEAT_FLUX(f,t), and BOUNDARY_HEAT_FLUX(f,t) functions within FLUENT. Since this was given to me by FLUENT support and there is no documentation on it, I was wondering if anyone has experience working with these functions. Particularly, I was wondering if there are cell equivalent functions, or do I have to use the face functions and then extract that information into my cell calculations? How would one couple the face to cell information? I was thinking about creating a global array and placing all the flux values there, but I am not well versed in FLUENT C yet and am not sure how to have the face's corresponding cell provide the information.

Any help is very appreciated!

ximik · May 4, 2011, 17:34

So i think I figured out my mistake, just in case anyone is curious/may need to figure this out in the future.

The mistake originated from my (lack of) understanding of the cell/face difference. Even if there is a cell equivalent to the functions I was talking about, it would just be easier to rewrite my UDF portion that deals with the radiation in terms of the faces, rather than cells.

It should be still possible to store the face value information in an outside array somehow, but I don't think that would be as accurate.

May 3, 2011, 20:48	interchanging face information with cell information/ radiation flux UDF	#1
ximik New Member Join Date: May 2011 Posts: 18 Rep Power: 15	Hello all, First, I would like to say hello to this community. I have discovered CFD a year or so ago, and believe I truly found my calling. I live for this stuff. I hope to learn much from you all, as well contribute my humble opinions and advice. For my first question, I hope that someone can help me out with some FLUENT/C programming. I am writing a UDF (my first one!) that uses the F_SOLAR_SOURCE(f,t), BOUNDARY_RAD_HEAT_FLUX(f,t), and BOUNDARY_HEAT_FLUX(f,t) functions within FLUENT. Since this was given to me by FLUENT support and there is no documentation on it, I was wondering if anyone has experience working with these functions. Particularly, I was wondering if there are cell equivalent functions, or do I have to use the face functions and then extract that information into my cell calculations? How would one couple the face to cell information? I was thinking about creating a global array and placing all the flux values there, but I am not well versed in FLUENT C yet and am not sure how to have the face's corresponding cell provide the information. Any help is very appreciated!

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May 4, 2011, 17:34		#2
ximik New Member Join Date: May 2011 Posts: 18 Rep Power: 15	So i think I figured out my mistake, just in case anyone is curious/may need to figure this out in the future. The mistake originated from my (lack of) understanding of the cell/face difference. Even if there is a cell equivalent to the functions I was talking about, it would just be easier to rewrite my UDF portion that deals with the radiation in terms of the faces, rather than cells. It should be still possible to store the face value information in an outside array somehow, but I don't think that would be as accurate.