[Bruno Machado]

Originally Posted by gaza

Hi Bruno and Farzin,
@Farzin:
I compiled this code:

#include "udf.h"
DEFINE_EXECUTE_AT_END(myFunc)
{
 Domain *d;
 /* Integrate dissipation. */
    real sum_diss=0.;
    cell_t c;
    face_t f;
    Thread *t;
    const int ID = 11;

    d = Get_Domain(1); /* mixture domain if multiphase */
    thread_loop_c(t,d)
    {
        if (FLUID_THREAD_P(t))
        {
            begin_c_loop(c,t)
                C_UDMI(c,t,0) = C_T(c,t);
            end_c_loop(c,t)
        }
    }
    


    //t = Lookup_Thread(d,ID);
    thread_loop_f(t,d)
    {
        //if (FLUID_THREAD_P(t))
        //if (NNULLP(THREAD_STORAGE(t,SV_UDM_I)))
        
            begin_f_loop(f,t)
                F_UDMI(f,t,0) = F_T(f,t);
            end_f_loop(f,t);
        
        
    }
}

and it gave the: received a fatal signal (Segmentation fault).

@Bruno:
I do not agree with you because I compared data for Static temperature and C_T that was assigned to UDM. Each value was the same but boundary value.
So I agree with Farzin that I have to set face value also with F_T, however I do not know how???

Here mvee wrote that he solved this problem but he unfortunately didn't provide the code:

http://www.cfd-online.com/Forums/flu...g-udm-uds.html

you are using the same number for the C_UDMI and F_UDMI.
The segmentation error usually is regarding some information that is required but isn't available yet (like gradient in the first iteration, for example).

In addition to that, are you comparing your values using node or cell values?

[gaza]

I compared node values taken from the line (option node values is picked in the plot menu).
What do you mean saying "you are using the same number for the C_UDMI and F_UDMI"??

[gaza]

Have a look at this post

http://www.cfd-online.com/Forums/flu...tml#post582575

I used another code and compared node and cell values for C_T, UDM and UDS.
There are differences between C_T and UDS and UDM. For UDM and UDS differences occur only at boundary. Why does it occur? How to fix it? Can anybody help?

[alinik]

Farzin,

This might be not completely relevant to the topic.
In my UDF whenever I am having C_UDSI_G in my adjust function, I receive segmentation error. I saw that in this code you are also using that and I am assuming you compiled and ran it without having any error. Is that right?
Did you ever get a segmentation error because of C_UDSI_G?

Thanks,

Ali

Originally Posted by FarzinD

One thing I'm suspicious of is that I didn't allocate face values of UDM and the contours are face values indeed.
Here's the related part of the UDF:

DEFINE_ADJUST(adjust_vorticity_calc,domain)
{
    int n;
    Thread *t,t0,t1;
    cell_t c,c0,c1;
    face_t f;

    //Calculating Vorticity for Cell Centers
    thread_loop_c(t,domain)
    {
        begin_c_loop(c,t)
        {
            C_UDSI(c,t,Vorticity_I) = VORI(c,t);
            C_UDSI(c,t,Vorticity_J) = VORJ(c,t);
            C_UDSI(c,t,Vorticity_K) = VORK(c,t);
        }
        end_c_loop(c,t);
    }

    //Calculating Vorticity Derivatives
    for (n=Vorticity_I; n<Vorticity_I+3; n++)
    {
        uds_derivatives(domain,n);
    }


    thread_loop_c(t,domain)
    {
        begin_c_loop(c,t)
        {
            C_UDMI(c,t,Vorticity_I) = C_UDSI(c,t,Vorticity_I);
            C_UDMI(c,t,Vorticity_J) = C_UDSI(c,t,Vorticity_J);
            C_UDMI(c,t,Vorticity_K) = C_UDSI(c,t,Vorticity_K);
            ND_D(C_UDSI(c,t,G_Vorticity_Ix),C_UDSI(c,t,G_Vorticity_Iy),C_UDSI(c,t,G_Vorticity_Iz),=,\
                C_UDSI_G(c,t,Vorticity_I)[0],C_UDSI_G(c,t,Vorticity_I)[1],C_UDSI_G(c,t,Vorticity_I)[2]);
            ND_D(C_UDSI(c,t,G_Vorticity_Jx),C_UDSI(c,t,G_Vorticity_Jy),C_UDSI(c,t,G_Vorticity_Jz),=,\
                C_UDSI_G(c,t,Vorticity_J)[0],C_UDSI_G(c,t,Vorticity_J)[1],C_UDSI_G(c,t,Vorticity_J)[2]);
            ND_D(C_UDSI(c,t,G_Vorticity_Kx),C_UDSI(c,t,G_Vorticity_Ky),C_UDSI(c,t,G_Vorticity_Kz),=,\
                C_UDSI_G(c,t,Vorticity_K)[0],C_UDSI_G(c,t,Vorticity_K)[1],C_UDSI_G(c,t,Vorticity_K)[2]);
        }
        end_c_loop(c,t);
    }
}



void uds_derivatives(Domain *domain, int n)
{
    MD_Alloc_Storage_Vars(domain, SV_UDSI_RG(n), SV_UDSI_G(n), SV_NULL);
    Scalar_Reconstruction(domain, SV_UDS_I(n), -1, SV_UDSI_RG(n), NULL);
    Scalar_Derivatives(domain, SV_UDS_I(n), -1, SV_UDSI_G(n), SV_UDSI_RG(n), NULL);
    return;
}

[gaza]

Hi Farzin,
Segmentation error appears when you try to access variable that is not allocated or you perform accessing in wrong manner. Have you set correct values of UDSI? Have you turned on keep memory being free?

[alinik]

Originally Posted by gaza

Hi Farzin,
Segmentation error appears when you try to access variable that is not allocated or you perform accessing in wrong manner. Have you set correct values of UDSI? Have you turned on keep memory being free?

Hi Gaza,

I am adjusting a UDM and in that I am using C_UDSI_G.
I get the segmentation error. Any idea how to solve it?

Thanks,
Ali

[sina_sls]

Originally Posted by Bruno Machado

you are using the same number for the C_UDMI and F_UDMI.
The segmentation error usually is regarding some information that is required but isn't available yet (like gradient in the first iteration, for example).

In addition to that, are you comparing your values using node or cell values?

Hello,

How can i change UDS boundary value in a Define Adjust UDF? i mean how can i call UDS boundary value to changing in a UDF of Define Adjust?

Regards,