[Yijun Lu]

In "Modeling of Dielectric-Barrier Discharge ActuatorImplementation, validation and generalization of an electrostatic model", there is a UDF :

#include "udf.h"
#include "math.h"
#include "sg_udms.h"
#define debye 0.001
#define rhomax 0.0008
#define phimax 5000
#define sigma 0.003
#define rholoc 0.5

enum {
phi,
rho
};

enum {
Ex,
Ey,
Fx,
Fy,
Fm
};

/* CALCULATION OF ELECTRIC FIELD STRENGTH */

DEFINE_ADJUST(udf_adjust, domain)
{
Thread *t;
cell_t c;

thread_loop_c(t,domain)
{
begin_c_loop(c,t)
{
C_UDMI(c,t,Ex)=-C_UDSI_G(c,t,phi)[0];
C_UDMI(c,t,Ey)=-C_UDSI_G(c,t,phi)[1];
}
end_c_loop(c,t)
}
}

/* DEFINITION OF SOURCE OF HELMHOLTZ EQUATION */

DEFINE_SOURCE(rho_source, c, t, dS, eqn)
{
real source;
source=-pow(debye,-2)*C_UDSI(c,t,rho);
dS[eqn]=-pow(debye,-2);
return source;
}

/* DEFINITION OF X-MOMENTUM SOURCE TERM */

DEFINE_SOURCE(X_Source, c, t, dS, eqn)
{
real Sourcex;
Sourcex=-rhomax*phimax*C_UDSI(c,t,rho)*C_UDSI_G(c,t,phi)[0];
dS[eqn]=-rhomax*phimax;
C_UDMI(c,t,Fx)=Sourcex;
return Sourcex;
}

/* DEFINITION OF Y-MOMENTUM SOURCE TERM */

DEFINE_SOURCE(Y_Source, c, t, dS, eqn)
{
real Sourcey;
Sourcey=-rhomax*phimax*C_UDSI(c,t,rho)*C_UDSI_G(c,t,phi)[1];
dS[eqn]=-rhomax*phimax;
C_UDMI(c,t,Fy)=Sourcey;
C_UDMI(c,t,Fm)=sqrt(C_UDMI(c,t,Fx)*C_UDMI(c,t,Fx)+ C_UDMI(c,t,Fy)*C_UDMI(c,t,Fy));
return Sourcey;
}

/* DISTRIBUTION FUNCTION ON WALL */

DEFINE_PROFILE(rho_profile,thread,i)
{
float r[3];
float x;
real xloc;
face_t f;

begin_f_loop(f,thread)
{
F_CENTROID(r,f,thread);
xloc = r[0];
F_PROFILE(f,thread,i)=exp(-pow((xloc-rholoc),2)/(2*pow(sigma,2)));
}
end_f_loop(f,thread)
}

here are the steps I take:
(1) [IMG]C:\Users\Luyijun\Desktop\complie udf.png[/IMG]

compile the UDF successfully.

(2) [IMG]C:\Users\Luyijun\Desktop\define UDM.png[/IMG]

then define the number of UDM, which is 5.

(3) [IMG]C:\Users\Luyijun\Desktop\define UDS.png[/IMG]

then define the number of UDS, which is 2.

(4) [IMG]C:\Users\Luyijun\Desktop\x mom.png[/IMG]

then insert the x momentum as a source term, as well as y momentum, which is not shown here, but the same process.

(5) [IMG]C:\Users\Luyijun\Desktop\confuse UDS.png[/IMG]

then this is what confuses me. User Scalar 0 should be "udf rho_source::lib.." and User scalar 1 should be "udf rho_profile..."?

(6) [IMG]C:\Users\Luyijun\Desktop\control.png[/IMG]

then should I solve the 4 equations here?


Could someone help me solve this UDF problem? I would appreciate that!