Macros for discrete ordinate, non gray model

yashmash · January 23, 2012, 05:54

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?

Thanks!

Yash

aliemadi · March 19, 2012, 03:13

Hello Yash
you can access to Incident radiation of each cell by using the following macro(in DOM):
C_STORAGE_R_XV(c,t,SV_DO_IRRAD,i)
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:
DEFINE_GRAY_BAND_ABS_COEFF(name,c,t,nb)

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
Ali

January 23, 2012, 05:54	Macros for discrete ordinate, non gray model	#1
yashmash New Member Join Date: Jun 2011 Posts: 18 Rep Power: 15	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? Thanks! Yash

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March 19, 2012, 03:13		#2
aliemadi New Member Ali Emadi Join Date: Jan 2011 Posts: 18 Rep Power: 15	Hello Yash you can access to Incident radiation of each cell by using the following macro(in DOM): C_STORAGE_R_XV(c,t,SV_DO_IRRAD,i) 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: DEFINE_GRAY_BAND_ABS_COEFF(name,c,t,nb) 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+0.001T; break; case 1 : abs_coeff = 2.7 + 0.005T; break; } return abs_coeff; } good luck Ali