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sam October 25, 2005 11:38

Help needed with UDF
I want to move the cells on a wall normal to the cell surface in cylindrical co-ordinates for an unsymmetrical wall about the origin. Any help with the following UDF is highly appreciated. thanks, Samir

#include "udf.h"

DEFINE_GRID_MOTION(wall,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 = 0.66 * dt);

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

NV_S(omega, =, 0.0); NV_D(axis, =, 1.0, 0.0, 1.0); NV_D(origin, =, 0.0, 0.0, 0.0);





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 */

if (NODE_X(v) > 0.020 && NODE_POS_NEED_UPDATE (v))


/* indicate that node position has been update

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


omega[1] = 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); }

zubier October 25, 2005 13:45

urgent query
hi all would you please send me tutorial of case file and solution file of how to simulate the electrical field in cylidrical pipe of flowing fluid. iam highly appreciate your help thanks regard

Md. Tajul Islam October 25, 2005 23:06

Re: Help needed with UDF
I need a C code UDF for fluent for slip boundary condition microflow when the Knudsen number<=0.1. Help from anyone is apreciated. Tajul

Md. Tajul Islam October 25, 2005 23:09

Re: urgent query *NM*

zubier October 26, 2005 02:42

Re: urgent query
Dear MR MOHAMMAD TAJUL ISLAM how are u and ramadan kareem i didn't recieve your reply regarding my qustion in my previus massage hope u send it again thanks

Md. Tajul Islam October 26, 2005 02:48

Re: urgent query
As salam. I am not expert in this regard. My posting was a mistake.

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