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Please help - Assign volatile mass fraction to particle

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Old   July 14, 2022, 10:29
Default Please help - Assign volatile mass fraction to particle
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Benjamin Ortner
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Hello everyone!

I am using the DEFINE_DPM_INJECTION_INIT from the UDF guide because I need to assign initial char and volatile massfractions to my particles - additionaly to the standard properties - but I just cant get it to work.

The UDF from the manual is fine, I can even assign the volatile fraction from a file to the USER_REAL which they describe in the documentation, but fluent does not let me write to the DPM_VOLATILE_FRACTION(p). So I know reading from the file is not the problem. What am I doing wrong here? Fluent ignores my code and after initialization the particles have the same volatile and char mass fraction according to the material definition.

This works:
/* From the rest of the line, determine the volatile mass fraction,
* add assign to the new particle’s user real
sscanf(strchr(rest, ':')+1, "%lg", &(PP_USER_REAL(p, 0)));

This does not:

/* From the rest of the line, determine the volatile mass fraction,
sscanf(strchr(rest, ':')+1, "%lg", &(DPM_VOLATILE_FRACTION(p)));

Thank you in advance!
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Old   July 14, 2022, 22:31
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AlexanderZ will become famous soon enoughAlexanderZ will become famous soon enough
from my point of view, problem could be in initialization macro you are using,
VOLATILE_FRACTION could be not determined yet, howeve, you are trying to access the data
best regards

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dpm, fluent, initialization, udf, volatile

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