CFD Online Discussion Forums - help with dynamic mesh

I wrote the following UDF code:

Code:

 

/**********************************************************

node motion based on simple beam deflection equation

compiled UDF

**********************************************************/

#include "udf.h"

DEFINE_GRID_MOTION(beam,domain,dt,time,dtime)

{

Thread *tf = DT_THREAD(dt);

face_t f;

Node *v;

real NV_VEC(omega), NV_VEC(axis), NV_VEC(dx);

real NV_VEC(origin), NV_VEC(rvec);

real sign;

int n;

 

/* set deforming flag on adjacent cell zone */

SET_DEFORMING_THREAD_FLAG(THREAD_T0(tf));

sign =5 * time;

 

Message ("time = %f, omega = %f\n", time, sign);

 

NV_S(omega, =, 0.0);

NV_D(axis, =, 0.0, 1.0, 0.0);

NV_D(origin, =, 0.0, 0.0, 0.152);

 

begin_f_loop(f,tf)

{

f_node_loop(f,tf,n)

{

v = F_NODE(f,tf,n);

/* update node if x position is greater than 0.02

and that the current node has not been previously

visited when looping through previous faces */

 

/* indicate that node position has been update

so that it's not updated more than once */

NODE_POS_UPDATED(v);

omega[1] = 0.001*sin(6.28*NODE_X(v)-sign);

NV_VV(rvec, =, NODE_COORD(v), -, origin);

NV_CROSS(dx, omega, rvec);

NV_S(dx, *=, dtime);

NV_V(NODE_COORD(v), +=, dx);

}

}

　

end_f_loop(f,tf);

}

when I run it's written to me the following error: received a fatal signal (Segmentation fault)

thanks for the help