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About this Block

What it does: The Import Superelement block imports a .bdf and .fem file to represent structural components that serve as efficient building blocks in larger nTop simulations.
  • A superelement is a reduced-order model of a larger FEA model, representing its stiffness and mass properties with a smaller set of degrees of freedom at its boundary. The imported superelement can be used directly as a domain in FEA and optimization problems.
Common uses:
  • Incorporating pre-analyzed, complex components into a larger assembly for system-level analysis without needing to re-mesh or re-solve the full component.
  • Connecting superelements to other FE domains using rigid connectors for efficient analysis of large assemblies.
  • Applying boundary conditions directly to the external nodes of the superelement.
Tips
  • Ensure that the .bdf file containing the superelement’s stiffness and mass properties corresponds correctly to the .fem file defining the global coordinates of the external grid points.
    • Verify that the selected Unit System in the block input matches the unit system used to create the superelement files. This is crucial for accurate results.
    • Remember that the FE points derived from the superelement’s properties cannot be used to define a separate FE domain.

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Example File

Download Example: Superelement ExampleSuperelement Example Imports a Superelement file from an external location. The .bdf file should contain the stiffness and mass properties, as well as the external grid IDs of the Super Element. The .fem file should contain the corresponding global coordinates of the external grid points.

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Inputs

NameTypeDescription
Dmig fileFile PathPath to the .bdf file containing the superelement’s stiffness, mass properties, and external grid ids.
Grid fileFile PathPath to the .fem file defining the global coordinates of the superelement’s external grid points.
Unit systemUnit SystemThe unit system used for the imported superelement. this ensures consistent translation of its properties into the current analysis unit system.

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Outputs

Type
Superelement