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Optixxx January 17, 2004 17:37

Temperature Functions for walls
 
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I want to set for a wall a time-dependent temperature

1. 0-10 min temp is increasing linear from 300 to 400k 2. after 10 min to 60min temp is constant 400k

Sure that must be done with unsteady time steps lets say a time step has 0.5 sec

Sorry,im learning UDF atm and not familiar with it atm.

with my small programming knowledge

if t<= 1200

T=T+0,0833333 else

T=400 end if

10min=1200 timesteps and 0,08333= 100/1200

can someone help me..setting a profile or UDF for it?

would be happy about any help

Optixxx


TAMO2 January 18, 2004 21:21

Re: Temperature Functions for walls
 
You don't need time step. And time scale is "second".

Please use the file as below; cut and paste, and name as "it.c", and read Define/User-Defined/Functions/Interpreted and write in "Source File Name" as "it.c"

and

Define/Boundary Conditions/

If you are Fluent User, after explanation will not be necessary.

/* -------increasing temperature file--------- */

#include "udf.h"

/* temperatu define */

DEFINE_PROFILE(temperature_profile,thread,position ) { face_t f;

begin_f_loop(f,thread)

{

real t = RP_Get_Real("flow-time");

if ( t < 600.0 )

F_PROFILE(f,thread,position) = 300.0+0.16666667 * t;

else if ( t < 3600.0 )

F_PROFILE(f,thread,position) = 400.0;

else

F_PROFILE(f,thread,position) = 400.0;

} end_f_loop(f,thread) }

Optixxx January 19, 2004 07:11

Re: Temperature Functions for walls
 
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Wonderbra

It works without any errors...many Thx TAMO2 Tested it on the surface intergal result-panel

Greetz Optixxx


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