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Errors in defining a source term

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Old   February 10, 2014, 15:02
Default Errors in defining a source term
  #1
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Hi all,

I'm having some trouble with a source term. I used the species transport and reaction model but since the model contains polymers, I don't know the accurate standard state enthalpy. So I set the standard state enthalpy to 0 and specified a reaction source term as follows:

/*UDF for energy source term of the reactions*/

#include "udf.h"
#define Aw 1385.;
#define Ew 3.266e+4;
#define AOH 1.7348;
#define EOH 4.04e+4;
#define Rg 8.314;
#define cw0 776.74;
#define coh0 3032.56;
#define cn0 4581.40;
#define delhyd 7.075e+4;
#define delwat 8.6e+4;
DEFINE_SOURCE(energy_source1,c,t,dS,eqn)
{
int j;
int k;
real convoh;
real convw;
real q;
real n;
real source;
Material *m = THREAD_MATERIAL(t);
char *name = "oh";
char *name1 = "h2o<l>";
j = mixture_specie_index(m,name);
k = mixture_specie_index(m,name1);
convoh=(0.424-C_YI(c,t,j))/0.424;/*the comversion of oh*/
convw=(0.0127-C_YI(c,t,k))/0.0127;/*the comversion of h2o<l>*/
q=AOH*exp(-EOH/Rg/C_T(c,t))*coh0*(1.-convoh)*(cn0-2.*cw0*convw-coh0*convoh);/*The coh0*dXoh/dt*/
n=Aw*exp(-Ew/Rg/C_T(c,t))*cw0*(1.-convw);/*The cw0*dXw/dt*/
source = delhyd*q+delwat*n;/*The cw0*dXw/dt*delwater+coh0*dXoh/dt*delhyd*/
dS[eqn]=0;
return source;
}

And I'm getting the errors when building the libudf:
..\..\src\energy_source1.c(30) : error C2143: syntax error : missing ')' before ';'
..\..\src\energy_source1.c(30) : error C2100: illegal indirection
..\..\src\energy_source1.c(30) : error C2143: syntax error : missing ';' before '/'
..\..\src\energy_source1.c(30) : error C2143: syntax error : missing ';' before '/'
..\..\src\energy_source1.c(30) : error C2100: illegal indirection
..\..\src\energy_source1.c(30) : error C2143: syntax error : missing ')' before ';'
..\..\src\energy_source1.c(30) : warning C4552: '*' : operator has no effect; expected operator with side-effect
..\..\src\energy_source1.c(30) : error C2100: illegal indirection
..\..\src\energy_source1.c(30) : warning C4552: '-' : operator has no effect; expected operator with side-effect
..\..\src\energy_source1.c(30) : error C2100: illegal indirection
..\..\src\energy_source1.c(30) : error C2143: syntax error : missing ';' before ')'
..\..\src\energy_source1.c(31) : error C2143: syntax error : missing ')' before ';'
..\..\src\energy_source1.c(31) : error C2100: illegal indirection
..\..\src\energy_source1.c(31) : error C2143: syntax error : missing ';' before '/'
..\..\src\energy_source1.c(31) : error C2143: syntax error : missing ';' before '/'
..\..\src\energy_source1.c(31) : error C2100: illegal indirection
..\..\src\energy_source1.c(32) : error C2100: illegal indirection
..\..\src\energy_source1.c(32) : warning C4552: '+' : operator has no effect; expected operator with side-effect
..\..\src\energy_source1.c(32) : error C2100: illegal indirection

Can anyone help me??
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Old   February 10, 2014, 15:19
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  #2
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pakk will become famous soon enough
The #defines that you start with are wrong.
Instead of
Code:
#define Aw 1385.;
you should use
Code:
#define Aw 1385.
so without the semicolon ( ; ) at the end. The same for all those definitions.

The (pre-)compiler will replace things literally. So when you wrote
Code:
q=AOH*exp(...
the pre-compiler sees "AOH", remembers that this should be replaced by "1.7348;", and the result is
Code:
q=1.7348;*exp(...
This is giving the errors.
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Old   February 10, 2014, 20:56
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Thank you so much for your reply pakk
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