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6DOF: can't compute angular acceleration

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Old   June 17, 2009, 08:27
Default 6DOF: can't compute angular acceleration
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Laurent B
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I everybody,

When i use the following 6dof properties :
prop[SDOF_MASS]=0.0014;
prop[SDOF_IXX]=2.333333e-8;
prop[SDOF_IYY]=2.333333e-8;
prop[SDOF_IZZ]=2.333333e-8;

Fluent display the message :
Info: 6DOF: can't compute angular acceleration.
Check moments/products of inertia.

If i increase moments of inertia (1e-6 for example) the message disapear. Any idea ?
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Old   January 5, 2011, 10:03
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The SDOF variables can only process solid body moments of inertia>=1e-06.

Unfortunately.
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Old   December 12, 2013, 05:34
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Quote:
Originally Posted by Will Anderson View Post
The SDOF variables can only process solid body moments of inertia>=1e-06.

Unfortunately.
If this is correct than I am dissapointed in fluent developers

Also, when looking into 6 dof theory one cannot but wonder how brief it is. One could hope for better explanations about conservation of angular momentum equations (or Euler equations), specially since 6 dof solver is "solving" these equations using already establieshed numerical method.

I wrote with my friend our own "6 DOF solver code" in under 80 lines of code and it can calculate Euler angles (pitch roll and yaw angles) for bodies with body moments of inertia>=1e-06.
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Old   March 26, 2015, 23:14
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Quote:
Originally Posted by Will Anderson View Post
The SDOF variables can only process solid body moments of inertia>=1e-06.

Unfortunately.
Unbelievable! How come!
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