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ambareesh13 June 7, 2010 07:43

incorrect grid motion
I am modelling flow around a vibrating cylinder.i have successfully compiled and hooked this UDF but i am continuously getting this error.

Warning: incorrect grid motion UDF valve::libudf on zone 6 (assuming no motion).
is something wrong with my UDF or compiler

This is my UDF


#define A4 1.25
#define F4 0.255

DEFINE_CG_MOTION(vibration, dt, cg_vel, cg_omega, time, dtime)
real st;
real va;

va = A4*2*M_PI*F4;

cg_vel[0] = 0.0;
cg_vel[1] = va*cos(2*M_PI*F4*time);
cg_vel[2] = 0.0;

NV_S(cg_omega, =, 0.0);


enry July 14, 2010 04:51

Hi ambareesh13,
I have the same problem, compiling a UDF written for fluent 6.3.26... I wrote an UDF that work well in fluent 6.3.26, but it doesn't work when I compile the same UDF in fluent 12. I tried also to compile an other udf finding on cfd on line, that was written for fluent 12, but the same problem appears on the screen.
Have you solved your problem? Could be a library problem?
Thanks in advance.

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