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Error Using UDF for Multiphase Mass Transfer Problem

Hi,

I am trying to implement a simple UDF to understand bubble growth using a VOF model. The purpose of the UDF is to identify zones where interface lies and put a constant source term. Below is the UDF.

Code:

#include "udf.h"

#include "mem.h"

#include "sg.h"

#include "sg_mphase.h"

#include "sg_vof.h"

#include "flow.h"



DEFINE_MASS_TRANSFER(mass_trnsfr, c, mixture_thread, from_phase_index, from_species_index, to_phase_index, to_species_index)

{

  Thread *tp_l, *tp_v;

  real rate;

  tp_v = THREAD_SUB_THREAD(mixture_thread, to_phase_index);

  tp_l = THREAD_SUB_THREAD(mixture_thread, from_phase_index);

  real EPS;

  EPS = 0.05;

  if ((EPS < C_VOF(c,tp_l))&&(C_VOF(c,tp_l)<1-EPS))

    {

      rate = 0.01;

    }

  else

    {

      rate = 0;

    }

  return rate;



}

So now, while I interpret it, it gives the following error:
Line 7: Syntax error

If I compile it, it successfully gets compiled, but when I go to the Interactions tab to use the UDF, it says:
No user-defined functions have been loaded.

Please let me know.

I am using a linux (Red Hat Enterprise Edition) 64 bit computer. The FLUENT version is 14.0.0.

Thanks,
Ajinkya

Found the error. Basically, what I think is happening, is that when you declare a variable (variable EPS is of type real) and when you define a variable (EPS = 1e-3) are two seperate things in C. It is important that all your variable declarations be at the start of the function. (eg. double EPS, tolval, y1, y2; int x1, x2; etc.) and then followed by the respective definitions (eg. x1 = 3; y1= 2.21143; etc.).
Failing to do so, the C comiler detects this as an error. This is not a limitation while using C++. Only C.