Modelling Flexible Bodies in Dymola and Modelica
Flexible Bodies can be included within Dymola MultiBody models using two different libraries. The first, called the FlexibleBodies library, is used to model flexible beams defined by specifying their geometrical and physical properties as straight, homogeneous and isotropic beams. The second is called the FlexBody library and uses reduced Finite Element models to define the flexible body.
The FlexibleBodies Library
The Flexible Bodies library defines the beam model using geometry and material properties and takes in to account bending in two planes, lengthening and torsional deflections. The deformations are discretised by eigenmodes that may be selected according to the actual needs of the modeller.
Read more about this library by downloading the brochure.
The FlexBody Library
Using features of the Finite Element analysis tools Nastran, Genesis or Abaqus, large, complex Finite Element models can be reduced to simpler models consisting of a small number of boundary nodes, or attachment points, and frequency modes. The reduced models still capture the same natural frequencies as the original Finite Element model within the range specified by the user.
The reduced models generated in Nastran, Genesis or Abaqus are then read in to Dymola using the FlexBody library. This then defines a flexible component which can be used as part of a Modelica system model. This approach enables the dynamics of the structure to be coupled to the behaviour of the complete system.
Read more about this library here.
