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Thermal expansion calculation for a system consisting of solid and fluid
Posted 21 gen 2014, 10:25 GMT-5 Heat Transfer & Phase Change, Computational Fluid Dynamics (CFD), Structural Mechanics Version 4.4 0 Replies
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I assign the materials "copper" to the outer cylinder and "water" to the inner cylinder.
I assign the physics:
- "heat transfer in solids" to the copper area and include
- "heat transfer in fluids" to the water area within the "heat transfer in solids" node (Thanks to Philip)
I include the "Structural Mechanics Module" and assign the "Solid Mechanics" node to the solid and to the water. (while I assume something else might be more suitable for water, but I cannot find a better choice). An error message made me define Posisson ratio, Young's modulus and thermal expansion coefficient of water manually. Then I chose "time dependent" study.
Now calculating the system, I get an error message:
"Undefined value found.
- Detail: Undefined value found in the stiffness matrix.
There are 1820 equations giving NaN/Inf in the matrix rows for the variable comp1.u.
at coordinates: (-0.0866029,0.0499994,0.1), (-0.0500011,0.0866019,0.1), (-0.0707113,0.07071,0.1), (-0.1,0,0.1), (-0.0965927,0.0258816,0.1), ...
There are 1820 equations giving NaN/Inf in the matrix rows for the variable comp1.v.
at coordinates: (-0.0866029,0.0499994,0.1), (-0.0500011,0.0866019,0.1), (-0.0707113,0.07071,0.1), (-0.1,0,0.1), (-0.0965927,0.0258816,0.1), ...
There are 1820 equations giving NaN/Inf in the matrix rows for the variable comp1.w.
at coordinates: (-0.0866029,0.0499994,0.1), (-0.0500011,0.0866019,0.1), (-0.0707113,0.07071,0.1), (-0.1,0,0.1), (-0.0965927,0.0258816,0.1), ...
and similarly for the degrees of freedom, NaN/Inf in the matrix columns."
Hello Hans Gennerich
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