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khaledhmz November 5, 2020 07:46

I receive "temperature limited to ... " after I Compile my UDF and start computing
 
Hello everyone,

I'm trying to specify the species mass fractions at the combustor mass flow inlet using udf but when I start the computing and after some iterations this message shows up in the console:

temperature limited to 5.000000e+03 in 5325 cells on zone 2 in domain 1.

and if I less the fluent computing the temperature decrease to reach 3000 k, its fixed at this value and won't decrease more as I want to be 1700k.


I don’t face this problem when I set constant inlet BC.

Does anybody have any idea what could be the problem?

pakk November 5, 2020 09:27

Quote:

Originally Posted by khaledhmz (Post 786848)
Hello everyone,

I'm trying to specify the species mass fractions at the combustor mass flow inlet using udf but when I start the computing and after some iterations this message shows up in the console:

temperature limited to 5.000000e+03 in 5325 cells on zone 2 in domain 1.

and if I less the fluent computing the temperature decrease to reach 3000 k, its fixed at this value and won't decrease more as I want to be 1700k.


I don’t face this problem when I set constant inlet BC.

Does anybody have any idea what could be the problem?

Your simulation is not converging. Can have so many reasons... If you used a UDF, show it.

khaledhmz November 5, 2020 10:04

this is my udf:

#include "udf.h"
#include "mem.h"
#define Y_CH4_in 0.032
#define Y_O2_in 0.225
DEFINE_PROFILE(mass_fraction, t, i)
{
face_t f;
begin_f_loop(f, t)
{
F_CENTROID(x, f, t);
F_PROFILE(f, t, i) = Y_CH4_in;
F_PROFILE(f, t, i) = Y_O2_in;
}
end_f_loop(f, t)
}


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