wall shear force with VOF

Jürgen

Hello everbody,

I am just working on a simple UDF to calculate the wall shear force, it looks like

DEFINE_EXECUTE_AT_END(force)

{

Domain *d = Get_Domain(1); /* 1: mixture*/

Thread *ft;

face_t f;

real shear_force[3];

real shear_force_0 = 0.0, shear_force_1 = 0.0, shear_force_2 = 0.0;

thread_loop_f(ft,d)

{

if ((THREAD_TYPE(ft) == THREAD_F_WALL))

{

begin_f_loop(f,ft)

{

NV_V(shear_force, =, F_STORAGE_R_N3V ,ft,SV_WALL_SHEAR));

shear_force_0 += shear_force[0];

shear_force_1 += shear_force[1];

shear_force_2 += shear_force[2];

}

end_f_loop(f,ft)

}

}

}

Anyway, the UDF results in the case of a transient two-phase VoF simulation differ from that one calculated by Fluent´s force report. If a single phase flow is used, the UDF results do well agree to the standard force report. Has anybody experience with wall shear calculation for the VoF model? Thank´s in advance