Hi

I have to write UDF to specify the fluid properties as a function of temperature therfore I have four codes (UDF) for viscosity ,density,thermal conductivity ,and Cp but when I interpret these UDF in fluent the fluent save only the last one and it only appear in the drop down list.My question is how can I interpret and save more than one UDF in fluent in the same time .

I will be happy for any help Thank you

You should compile your UDF's, but if you want to interpret you can keep all of your DEFINE macros (4 in your case) in the same source file with the include udf.h preprocessor directive.

p.s. I thought that the termal conductivity could not be altered by a UDF in Fluent.

Hi. You can keeping interpreting your UDF. You have to do like this:

DEFINE_xxx(xxxxxxx, .., ..) { write your first udf } in the same file you attach all the other udf's just placing them one after the other:

DEFINE_yyy(yyyyyy, .., ..) { write your first udf } DEFINE_zzz(zzzzzz, .., ..) { write your first udf }

At the end, when you interpret, you will find xxxxxxx yyyyyy zzzzzz in you drop down menus. Enjoy!

Giacomo

Hi. You can keeping interpreting your UDF. You have to do like this:

DEFINE_xxx(xxxxxxx, .., ..) { write your first udf } in the same file you attach all the other udf's just placing them one after the other:

DEFINE_yyy(yyyyyy, .., ..) { write your second udf }

DEFINE_zzz(zzzzzz, .., ..) { write your third udf }

At the end, when you interpret, you will find

xxxxxxx

yyyyyy

zzzzzz

in you drop down menus. Enjoy!

Giacomo

i remeber that you can not write a udf for thermal conductivity, it requires additional solver capabilities.please research this