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trantoan2008 June 27, 2012 04:36

Dynamic mesh with DEFINE_CG_MOTION problem
Hi all user!

I trying to simulate pitching of airfoil using UDF code as below. While I running simulation, I tried to check pitching angle at every time step that can be written in Fluent window. Additional, I accessed pitching angle of airfoil by using GUI like:
Define---Dynamic Mesh-->Zones
In Dynamic mesh zones form, I checked Center of Gravitation Orientation, and I found that there are slightly different pitch angle between this value and output value in Fluent window.
Anybody have experience in this case, please tell me. Thanks in advanced

#include "udf.h"
#include "stdio.h"

float pitch_angle,pi,rad;

DEFINE_CG_MOTION(trans1, dt, vel, omega, time, dtime)
pi = 3.1415926536;
vel[0] = 0.0 ;
vel[1] = 0.0 ;
vel[2] = 0.0 ;

omega[0] = 0.0 ;
omega[1] = 0.0 ;
omega[2] = 0.34906585*(pi/2)*cos((pi/2)*time);
pitch_angle = 0.34906585*sin((pi/2)*time)*(1/rad);
Message0("\n Time = %g\n",time);
Message0("\n Omega = %g\n",omega[2]);
Message0("\n Pitch = %g\n",pitch_angle);

mooby June 19, 2015 06:26

(Emergence) Dynamic mesh with DEFINE_CG_MOTION problem

I have exactly the same problem that calculated AOA does not correspond to orientation of angle in the simulation. how did you solve this problem ??

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