UDF for temperature gradient
I have wall i need to apply the current equation as boundary to it:
k*dT/dy=dT/dy where k thermal conductivity T local temperature how i can add it please ? did i need a UDF for it? 
Yes you do need UDF. I think you could use the 'DEFINE PROFILE' macro.

Hi
You need to use DEFINE_ADJUST function to set C_T_G as zero on the wall of your interest which is called using LOOK_UP_THREAD. Best wishes. Mvee 
what did you mean with C_T_G? can you write me the term and post me it here?
Quote:

C_T_G()  temperature gradient stored at cell locations. Please refer UDF manual.

C_T_G is used for compiling gradient over cells... but we need to calculate gradient over face thread!!!!!!!
so what we must to do??????? 
Temporal temperature derivative mass transfer udf
Hi guys,
I am modelling a solid biomass combustion system using a transient, Eulerian multiphase model in conjunction with a species transport model. I need to write a DEFINE_MASS_TRANSFER udf in order to determine the thermally driven rate of drying of the solid fuel. This requires the the determination of the time derivative of the particle temperature, which I do not know how to code. Please can someone help? Thank you guys in advance for your assistance. 
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