[amim]

Hello,

I am trying to simulate flow in rotary peristaltic pump. Basically 2D simulation where I deform one side of the tube by roller, move along the tube and the "undeform" back to it's original shape. I was adviced to use smoothing and remeshing.

Now the problem is that the deformation is basically not moving even thou it looks like the mesh is reacting and doing something. The udf which controls the motion can be seen below (I deleted some parts of the code for clarity as it is just calculation of the x a y velocity - the whole code is in the file below).

I also include the images of the settings.

Would be amazing if somebody would help me with this as I've been stuck at this for a while and I don't know what to try next. Can provide case if needed.

PS: There will be udf for the second roller as well but it should be the same so I am not including that. Also the udf doesn't include the inicial deformation as I don't know how to do that yet.


DEFINE_GRID_MOTION(peristaltic, domain, dt, time, dtime)
{

Thread *tf = DT_THREAD(dt);
face_t f;
Node *node_p;


vel_x = 2 * M_PI * rps * r_tube_middle;
vel_y = (d_tube - gab) / time_def;
time_360 = 1/rps;
time_180 = time_360 / 2;

SET_DEFORMING_THREAD_FLAG(THREAD_T0 (tf));

begin_f_loop(f, tf)
{
f_node_loop(f, tf, n)
{
node_p = F_NODE(f, tf, n); /*position of active node*/

if (NODE_POS_NEED_UPDATE(node_p))
{
NODE_POS_UPDATED(node_p);
/*position of active node (x,y direction)*/
x0 = NODE_X(node_p);
y0 = NODE_Y(node_p);
/*movement x-axis*/
NODE_X(node_p) = x0 + (vel_x * CURRENT_TIMESTEP);

if (CURRENT_TIME >= time_180)
{
y_new = y0 + (vel_y * CURRENT_TIMESTEP);
if (y_new > 0)
{
NODE_Y(node_p) = 0;
}
else
{
NODE_Y(node_p) = y_new;
}
}
}
}
}
end_f_loop (f, tf);
}

remesh_settigns.jpg

smoothing_settings.jpg

deformed_mesh.PNG

fluid.PNG

roller1.PNG