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laminar flow
Posted 2011年3月2日 GMT-5 06:18 Version 4.0a 1 Reply
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sir, i have checked material properties ..i have entered dynamic viscocity values which i have not entered before even then iam getting the error...
- Detail: Undefined value found in the equation residual vector.
There are 37309 degrees of freedom giving NaN/Inf in the vector for the variable mod1.u
at coordinates: (0.0019,0.000979,0.000978), (0.0019,0.000779,0.000978), (0.0019,0.000879,0.000978), (0.0019,0.000916134,0.000911068), (0.0019,0.000853269,0.000844136), ...
There are 37309 degrees of freedom giving NaN/Inf in the vector for the variable mod1.v
at coordinates: (0.0019,0.000979,0.000978), (0.0019,0.000779,0.000978), (0.0019,0.000879,0.000978), (0.0019,0.000916134,0.000911068), (0.0019,0.000853269,0.000844136), ...
There are 37309 degrees of freedom giving NaN/Inf in the vector for the variable mod1.w
at coordinates: (0.0019,0.000979,0.000978), (0.0019,0.000779,0.000978), (0.0019,0.000879,0.000978), (0.0019,0.000916134,0.000911068), (0.0019,0.000853269,0.000844136), ...
Kindly tell me the way to delete this error
- Detail: Undefined value found in the equation residual vector.
There are 37309 degrees of freedom giving NaN/Inf in the vector for the variable mod1.u
at coordinates: (0.0019,0.000979,0.000978), (0.0019,0.000779,0.000978), (0.0019,0.000879,0.000978), (0.0019,0.000916134,0.000911068), (0.0019,0.000853269,0.000844136), ...
There are 37309 degrees of freedom giving NaN/Inf in the vector for the variable mod1.v
at coordinates: (0.0019,0.000979,0.000978), (0.0019,0.000779,0.000978), (0.0019,0.000879,0.000978), (0.0019,0.000916134,0.000911068), (0.0019,0.000853269,0.000844136), ...
There are 37309 degrees of freedom giving NaN/Inf in the vector for the variable mod1.w
at coordinates: (0.0019,0.000979,0.000978), (0.0019,0.000779,0.000978), (0.0019,0.000879,0.000978), (0.0019,0.000916134,0.000911068), (0.0019,0.000853269,0.000844136), ...
Kindly tell me the way to delete this error
1 Reply Last Post 2011年3月2日 GMT-5 07:46
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Posted:
1 decade ago
Hi
normally it means that you have missed some material properties or some BC links between the physics. To model your "hair in the wind" I would start with the FSI physics (not really good in v4.0, you should update to latest version).
Then you need to check that each Domain Entity has sufficient material properties defined, that the air inlet outlet are OK , use symmetric flow conditions on top and sides. You need a rather long =3-5 times the hair antenna length for the air inlet to get the flow to stabilize (or use laminar inflow) and at least the half on the outlet
Define the required boundary conditions FOR each PHYSICS: structural, fluidics and then if you use FSI for the moving mesh ALE
Then you need to check (after having solved your error issue) that you have a dense enough mesh so that you are in a reasonable velocity flow for laminar (check the cell Reynolds number)
--
Good luck
Ivar
normally it means that you have missed some material properties or some BC links between the physics. To model your "hair in the wind" I would start with the FSI physics (not really good in v4.0, you should update to latest version).
Then you need to check that each Domain Entity has sufficient material properties defined, that the air inlet outlet are OK , use symmetric flow conditions on top and sides. You need a rather long =3-5 times the hair antenna length for the air inlet to get the flow to stabilize (or use laminar inflow) and at least the half on the outlet
Define the required boundary conditions FOR each PHYSICS: structural, fluidics and then if you use FSI for the moving mesh ALE
Then you need to check (after having solved your error issue) that you have a dense enough mesh so that you are in a reasonable velocity flow for laminar (check the cell Reynolds number)
--
Good luck
Ivar