Flexible Beams in Dymola

Abstract: Mechanical systems can be modeled by connecting rigid bodies with loads and other components. Prescribed motions and initial values can be defined in a system. The behaviour of the rigid bodies can then be studied and their motions can be computed. If a body is elastic the motion of some defined points are not identical to a rigid body when loads are affected. To model a mechanical system the dynamical tool Dymola can be used. Modelica is an open source, object-oriented modeling language and used in Dymola. So a rigid body object can be modified and developed to a flexible body for using in mechanical systems in Dymola. In multibody dynamics it is preferred to use the floating frame of reference formulation, i.e. large rigid body motion and small deformations with respect to body reference system. The aim of this master’s thesis was to implement a model for a general body and a model specic for a beam in Dymola. Equations for the models have been derived according to the floating frame of reference formulation and the finite element method. The body model is partial and with expan- sions in future work this model can be used with imported data from Abaqus. The beam model have been modeled and used in Dymola like a 3D Bernoulli beam. This model extends the body model and the equations and the parameters have been specified for a beam with geometry and material properties defined by the user. The beam model has been tested in mechanical systems and the results validated with corresponding tests in Abaqus.