[arailos]

Hi all,

I am simulating heat transfer from a cylindrical source immersed in a rectangular cavity and I am trying to find out how can I write a UDF in order to have thermally stratified layers with linear distribution of temperature in the whole domain of the tank at the initialization of the simulation.

I am really new to UDF and this is my first attempt.

So far I have written this code but....

///////////////////////////////////////
#include "udf.h"

DEFINE_INIT(linear_temp,d)

{
cell_t c;
Thread *t;
real x[ND_ND];
real Tt=338., Tb=288.;
real xb=0.,xt=-0.5;
real dT=(Tt-Tb)/(xt-xb);

/* loop over all cell threads in the domain */
thread_loop_c(t,d)
{
/* loop over all cells */
begin_c_loop_all(c,t)
{
C_CENTROID(xc,c,t);

C_T(c,t) = Tb+(x-xb)dT ;

}
end_c_loop_all(c,t)
}
}
///////////////////////////////

My tank has a height of 0.5m and is placed horizontally with the gravity vector pointing to the positive of x axis...The bottom temp is 288K and the top temp of the tank is 338K...I can clarify any details needed... The tank is place horizontally because I am going to solve it axisymmetrically and the axis boundary condition should have x-axis direction...

Thanks in advance....

[arailos]

hey all,

finally I did it...This is the appropriate code for my case...

////////////////////


#include "udf.h"

DEFINE_INIT(linear_temp,d)

{
cell_t c;
Thread *t;
real xc[ND_ND];
real myx;
real Tt=338., Tb=288.;
real xb=0.,xt=-0.5;
real dT=(Tt-Tb)/(xt-xb);

/* loop over all cell threads in the domain */
thread_loop_c(t,d)
{
/* loop over all cells */
begin_c_loop_all(c,t)
{
C_CENTROID(xc,c,t);

myx=xc[0]

C_T(c,t) = Tb+(myx-xb)dT ;

}
end_c_loop_all(c,t)
}
}
////////////////////

I just post it in case anyone is looking for something similar...