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yashmash January 23, 2012 05:54

Macros for discrete ordinate, non gray model
Hi all,

I am using the discrete ordinate, non gray radiation model. I am after the macros to access the incident radiation for each band and the absorption coefficient for each band as well.

Anyone able to assist?



aliemadi March 19, 2012 03:13

Hello Yash
you can access to Incident radiation of each cell by using the following macro(in DOM):
where i is the number of grey band and you can change it from 0 to the last band.
you yourself define absorption coefficient for each band! so you obviously know its value. If you want to define not a constant absorption coefficient for each band you can use it's standard macro:

as an example:
#include "udf.h"
DEFINE_GRAY_BAND_ABS_COEFF(user_gray_band_abs,c,t, nb)
real abs_coeff = 0;
real T = C_T(c,t);
switch (nb)
case 0 : abs_coeff = 1.3+0.001*T; break;
case 1 : abs_coeff = 2.7 + 0.005*T; break;
return abs_coeff;

good luck

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