[ozy]

Hi All,

i am trying to solve transport equation in fluent with udf. I wrote the udf for this and it is well compiled but when i run the simulation it gives error. please help me ?

My Udf is as follows
#include"udf.h"
#define dp 150.e-6
#define miu 1.7894e-5
#define rho 1.225
#define Cc (1.+0.066e-6/dp*(2.34+1.05*exp(-0.39*dp/0.066e-6)))
#define vs_x 0.0
#define vs_y (-998.2*dp*dp*9.81*Cc/(18.*miu))
#define vs_z 0.0

// dp=particle diameter
// miu=air densty
//rho=air density
//vk=kinematic viscisity of air
//Cc=cunningham correction factor
//Brownian=Brownian diffusion coefficient
//Sc=Schmidt number
//Sc3=pow(Sc,-1/3.)
//vs_x=x component of the settling velocity
//vs_y=y component of the settling velocity
//vs_z=z component of the settling velocity
/************************************************** *********************/
/* UDF to add gravitational settling velocity into the convective term */
/* of particle species conservation equation */
/************************************************** *********************/

DEFINE_UDS_FLUX(particle_flux, f, t, i)

{

real NV_VEC(vs_vec), NV_VEC(A);

real settling_flux;

real x[ND_ND];

// vs_vec=settling velocity vector
// A=face normal vector
// settling_flux=particle settling flux, which is a scalar
// x=position of face centroid

/* Define the settling velocity vector */

NV_D(vs_vec, = , vs_x, vs_y, vs_z);

/* obtain the face normal vector of the current face */

F_AREA(A, f, t);

/* calculate the superimposed mass flow vector */

if (!BOUNDARY_FACE_THREAD_P(t))

settling_flux = NV_DOT(vs_vec, A);

else

settling_flux = 0.0;

return (F_FLUX(f, t) / rho + settling_flux);
}