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heat transfer coefficient for the fluid / solid interface

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Old   July 7, 2014, 23:38
Default heat transfer coefficient for the fluid / solid interface
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sarah
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Hi,
I am using non-equilibrium model in porous zone in Ansys Fluent 14.5. for specifying heat transfer coefficient for the fluid / solid interface, I have written the following udf

#include "udf.h"
DEFINE_PROFILE(Heat_trans_coeff,t,i)
{
cell_t c;
real Nu,Re,Pr;
real dens, visc; /*Fluid*/
real cond, cp; /* Fluid*/
real d_p;
real por;/*Porosity of the bed*/
d_p=0.06;
por=0.36

begin_c_loop(c,t)
{
dens = C_R(c,t); /*Density of fluid*/
visc = C_MU_L(c,t); /*Viscosity fluid*/
cond = C_K_L(c,t); /*Conductivity fluid*/
cp = C_CP(c,t); /*Specific heat fluid*/
Re = ND_MAG(C_U(c,t),C_V(c,t),C_W(c,t))*d_p*dens*por/visc ; /*Reynolds number has been calculated based on pore velocity*/
Pr = cp*visc/cond ;
Nu = 2.+ 1.1 * pow(Re,0.6) * pow(Pr,1./3.);
F_PROFILE(c,t,i) = Nu*cond/d_p ;
}
end_c_loop(c,t)
}
However this code cannot be interpreted in FLUENT. The error message is "c_loop_last: undeclared variable"
I would be grateful if somebody help me!
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Old   July 29, 2014, 10:44
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Hello:

Were you able to solve your problem?
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Old   July 31, 2014, 02:50
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well, I changed some of the statements to constatnt parameter and the it run!
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Old   July 31, 2014, 08:59
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Sarah:
Thanks for your reply. Do you by any chance know how one can get the solid temperature at a specific point in the media by udf?

Thank you.
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Old   July 31, 2014, 14:57
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you're welcome
while you use non equilibrium model , the software creats solid zone itself so you can observe the variation of Temp on that ! also you can create new plane with specific points to see more details.

regards
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Old   August 23, 2014, 18:08
Default udf for heat-transfer-coefficient-fluid-solid-interface
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Dear Pr Sarah

I work on the heat transfer in porous media, and I need a UDF for the heat transfer coefficient fluid/solid that is a function of the solid temperarue and the fluid temperature

Thank's to answer me

Best regards
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