Learning Forum

[ehsan.sadeghi]

Hello

I have the following UDF structure for calculating gradients of UDS0 (potential). I start with calculation the UDS0 gradients in ADJUST macro, then I want to pass the calculated Ex, Ey and Ez to a SOURCE macro. My problem is that I am not sure if in my code structure Ex, Ey and Ez pass to Source function or not? how can I do that?

```

#include "udf.h"
DEFINE_EXECUTE_ON_LOADING(uds_names, uds_libnames)
{
    void Set_User_Scalar_Name(int i,char *name);
    Set_User_Scalar_Name(0,"potential");
    Set_User_Scalar_Name(1,"E_x");
    Set_User_Scalar_Name(2,"E_y");
    Set_User_Scalar_Name(3,"E_z");
    Set_User_Scalar_Name(4,"E");
    Set_User_Scalar_Name(5,"n");
}

enum
{
    potential,
    E_x,
    E_y,
    E_z,
    E,
    n,
    N_REQUIRED_UDS
};

DEFINE_ADJUST(grad_calc, domain)

{

/* calculate E_x, E_y, E_z; */

}

DEFINE_SOURCE(potential_source, cell, thread, dS, eqn)
{
real source;
source = 2.0*E_x;
return source;
}

```

[Rob]

I tend to calculate the values for the source terms directly, so E_x etc would be in the DEFINE_SOURCE part of the code. 

[ehsan.sadeghi]

so you mean I implment another DEFINE_ADJUST inside the DEFINE_SOURCE? or only the thread loop and face loop?

In DEFINE_ADJUST I calculate E_x, etc... then I need that parameter in source.

[Rob]

Do you need the DEFINE_ADJUST bit? 

[ehsan.sadeghi]

I don´t understand what you mean?

[Rob]

What does the DEFINE_ADJUST do that can't be done in the DEFINE_SOURCE routine?

[ehsan.sadeghi]

That´s what I was asking. I didn´t know that it already loops over domain and executes per iteration. Thanks for being so nice!!

[ehsan.sadeghi]

 

I did as you said, but for some reason I get error:

999999: mpt_accept: error: accept failed: No such file or directory

 

===================================================================================

= BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES

= RANK 0 PID 1228 RUNNING AT PC-ANSYS-157

= EXIT STATUS: -1 (ffffffff)

 

My code is:

#include”udf.h”
#define e 1.6e-19
#define epsilon0 8.854e-12
#define mu_p 1.35e-4
#define Dp 3.5e-6
DEFINE_EXECUTE_ON_LOADING(on_loading, libname)
{
    Set_User_Memory_Name(0,”Potential Source”);
    Set_User_Memory_Name(1,”Potential”);
    Set_User_Memory_Name(2,”Ex”);
    Set_User_Memory_Name(3,”Ey”);
    Set_User_Memory_Name(4,”Ez”);
    Set_User_Memory_Name(5,”Electric Field”);
    Set_User_Memory_Name(7,”x-Momentum Source”);
    Set_User_Memory_Name(8,”y-Momentum Source”);
    Set_User_Memory_Name(9,”z-Momentum Source”);
    Set_User_Scalar_Name(0,”Potential”);
    Set_User_Scalar_Name(1,”ion concentration”);
}

DEFINE_ADJUST(E_xyz,d)
{
Thread *t;
cell_t c;
thread_loop_c(t,d)
{
begin_c_loop(c,t)
{
C_UDMI(c,t,1) = C_UDSI(c,t,0) ;
C_UDMI(c,t,2) = -C_UDSI_G(c,t,0)[0] ;
C_UDMI(c,t,3) = -C_UDSI_G(c,t,0)[1] ;
C_UDMI(c,t,4) = -C_UDSI_G(c,t,0)[2] ;
C_UDMI(c,t,5) = NV_MAG(C_UDSI_G(c,t,0)) ;
C_UDMI(c,t,6) = C_UDSI(c,t,1) ;
}
end_c_loop(c,t)
}
}

/* Sets the gradient of phi (UDS-0) to equal E_x (UDS-1) and E_y (UDS-2), and sets face values */
DEFINE_SOURCE(phi_source,c,t,dS,eqn)
{    
real phi_source;
dS[eqn] = 0.0;
phi_source = -(e/epsilon0)*C_UDSI(c,t,1);
C_UDMI(c,t,0) = phi_source;
return phi_source;
}

DEFINE_SOURCE(momentum_x, c, t, dS, eqn)
{
real source;
dS[eqn] = 0.0;
source = e*C_UDMI(c,t,2)*C_UDSI(c,t,1);
C_UDMI(c,t,7) = source;
return source;
}

DEFINE_SOURCE(momentum_y, c, t, dS, eqn)
{
real source;
dS[eqn] = 0.0;
source = e*C_UDMI(c,t,3)*C_UDSI(c,t,1);
C_UDMI(c,t,8) = source;
return source;
}

DEFINE_SOURCE(momentum_z, c, t, dS, eqn)
{
real source;
dS[eqn] = 0.0;
source = e*C_UDMI(c,t,4)*C_UDSI(c,t,1);
C_UDMI(c,t,9) = source;
return source;
}

DEFINE_UDS_FLUX(flux_ions,f,t,i)
{
    cell_t c;
    cell_t c0, c1= -1;
    Thread *t0, *t1 = NULL;
    real NV_VEC(A), NV_VEC(E_vec), E_flux = 0.;
    real rho = C_R(c0,t0)+C_R(c1,t1);
    c0 = F_C0(f,t);
    t0 = F_C0_THREAD(f,t);
    F_AREA(A,f,t);
    if (BOUNDARY_FACE_THREAD_P(t))
    {
        E_flux = 0.0;
    }
    else
    {
        begin_c_loop(c,t)
        {
            F_UDMI(c,t,2) = C_UDMI(c,t,2) ;
            F_UDMI(c,t,3) = C_UDMI(c,t,2) ;
            F_UDMI(c,t,4) = C_UDMI(c,t,2) ;
        }
        end_c_loop(c,t)
    
    c1 = F_C1(f,t);
    t1 = F_C1_THREAD(f,t);
    NV_DS(E_vec, =, F_UDMI(c0, t0, 2), F_UDMI(c0, t0, 3), F_UDMI(c0, t0, 4), *, Dp);
    NV_DS(E_vec, +=, F_UDMI(c1, t1, 2), F_UDMI(c1, t1, 3), F_UDMI(c1, t1, 4), *, Dp);
    E_flux = NV_DOT(E_vec,A)/2.0;
    }

    if (i==1)
    {
        return (F_FLUX(f,t)/rho+E_flux);
    }
    else
        return (0.);
}