[uday sarkar]

Hi im trying to model unsteady heat transfer from wall with the following udf:

#include "udf.h"
DEFINE_PROFILE(unsteady_heat, thread, position)
{
face_t f;
begin_f_loop(f, thread)
{
real t = RP_Get_Real("flow-time");
F_PROFILE(f, thread, position) = 0.01072*(300.0+(1527.84*doubleexp(double(0.0854*t) )));
}
end_f_loop(f, thread)
}

However I am getting syntax error while compiling.
Can anybody help me out?
thanks in advance.

[vasava]

You have not declared 'doubleexp'. Also use of type double within the code may not be valid.

[uday sarkar]

hi thanks for the reply.
However "double exp (double x)" stands for the mathematical function exp(x) as defined under mathematical functions in udf help section.
does the error lie somewhere else?
please help.

[vasava]

When I try to compile it says that there is a ')' is missing. I strongly suspect that it is because of the type declaration with in the statement.

I dont have fluent license for couple of hours. I will check again and get back to you.

[vasava]

As I said earlier the error is in the declaration. Yes "double exp (double x)" stands for the mathematical function exp(x) but that doen not mean that you can use it as it is inside a statement.

Try this one, it works:

#include "udf.h"
DEFINE_PROFILE(unsteady_heat, thread, position)
{
face_t f;
double t1, t2;
real t = CURRENT_TIME;

begin_f_loop(f, thread)
{
real t = RP_Get_Real("flow-time");
t1 = 0.0854*t;
t2 = exp(t1);
F_PROFILE(f, thread, position) = 0.01072*(300.0+(1527.84*t2));
}
end_f_loop(f, thread)
}

[uday sarkar]

Thanks Vasava....
It works fine now...