[guido_88]

Hi, I've found this video on youtube:

http://www.youtube.com/watch?NR=1&fe...&v=_zh1e5jxJyg

Can anyone tell me all the steps and describe the udf that is necessary to do that? I need it for my thesis and I'm not able to do that alone. Thank you in advance

[ghost82]

Hi Guido,
this could be something like this (I haven't checked if it works):

#include "udf.h"

#define PI 3.14159265

DEFINE_GRID_MOTION(my_custom_udf,domain,dt,time,dtime)
{
    real p, q;
    face_t f;
    Node *v;
    int n;
    Thread *tf=DT_THREAD(dt);
    SET_DEFORMING_THREAD_FLAG(THREAD_T0(tf));
    begin_f_loop(f,tf)
    {
        f_node_loop(f,tf,n)
        {
            v=F_NODE(f,tf,n);
            if (NODE_POS_NEED_UPDATE (v))
            {
                NODE_POS_UPDATED(v);

                q=NODE_Y(v);
                p=(10*(sin(2.0*PI*62.5*time)))/100; /*from youtube video*/
                NODE_X(v)=p;
                NODE_Y(v)=q;
            }
        }
    }
    end_f_loop(f,tf);
}

You can draw a fixed mesh around the moving object and a "deforming" mesh around this fixed mesh; then assign udf to the fixed mesh and use layering method for dynamic mesh (structured grid).

Daniele

[granbycools]

Originally Posted by ghost82

You can draw a fixed mesh around the moving object and a "deforming" mesh around this fixed mesh; then assign udf to the fixed mesh and use layering method for dynamic mesh (structured grid).

Daniele

Hi Daniele,
are there any more detailed tutorials or instruction you can recommend how to do that?
I am trying to do a transient Ansys Fluent simulation with moving valves and I don´t know how to create a "deforming" mesh?
Any help would be very much appreciated.
Granbycools