[Qingsong]

Hi everybody.
In dynamic mesh, I use a UDF code to allow a rigid body only to translate in one direction and rotate in one direction. But the rigid body panel shows values on all the directions of Rigid Body Angular Velocity. It should be zero at x and z direction.

If anyone knows what happened, please tell me. Many thanks.

Regards, Qingsong

[D.M]

Hi,
this problem is mainly because of your code, try to change your UDF.

[Qingsong]

Hi, D.Malekian,

I've checked my UDF code many times, and I think it's OK. My code is as following:

#include "udf.h"

DEFINE_SDOF_PROPERTIES(test01, prop, dt, time, dtime)
{
prop[SDOF_MASS] = 4184.769;
prop[SDOF_IXX] = 1;
prop[SDOF_IYY] = 11141.947;
prop[SDOF_IZZ] = 1;

prop[SDOF_ZERO_TRANS_X] = TRUE;
prop[SDOF_ZERO_TRANS_Y] = TRUE;
prop[SDOF_ZERO_TRANS_Z] = FALSE;
prop[SDOF_ZERO_ROT_X] = TRUE;
prop[SDOF_ZERO_ROT_Y] = FALSE;
prop[SDOF_ZERO_ROT_Z] = TRUE;

}

[AHF]

Originally Posted by Qingsong

Hi everybody.
In dynamic mesh, I use a UDF code to allow a rigid body only to translate in one direction and rotate in one direction. But the rigid body panel shows values on all the directions of Rigid Body Angular Velocity. It should be zero at x and z direction.

If anyone knows what happened, please tell me. Many thanks.

Regards, Qingsong

is it 2D or 3D ?

if it is 2D , i maybe you should put Ixx and Iyy zero . ( not sure , just idea )

[Qingsong]

Originally Posted by AHF

is it 2D or 3D ?

if it is 2D , i maybe you should put Ixx and Iyy zero . ( not sure , just idea )

The calculation is 3D.

[Qingsong]

Thank you for your reply.

I finally solve the problem.

Maybe there is a bug in ANSYS 17.1 version. A bug relate to the calculation in the first mesh layer near the wall. When I set up all the calculations in a lower version(V16.1), it works well.