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Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. Numerical simulation of continuous systems with structural dynamics
 Zupancic, B. ; Federation of European Simulation Societies EUROSIM; Slovenian Society for Simulation and Modelling SLOSIM: EUROSIM 2007, 6th EUROSIM Congress on Modelling and Simulation : Ljubljana, Slovenia, 913 Sept., 2007, Proceedings Vienna: ARGESIM, 2007 ISBN: 9783901608322 ISBN: 390160832X Abstract S.279, 9 S. 
 Congress on Modelling and Simulation <6, 2007, Ljubljana> 

 Englisch 
 Konferenzbeitrag 
 Fraunhofer IIS, Institutsteil Entwurfsautomatisierung (EAS) () 
 structural dynamics; hybrid system; discretecontinuous simulation; simulation algorithm; Modelica 
Abstract
In this paper, "continuous systems with structural dynamics" shall be understood asdynamical systems consisting of components with continuous and/or discrete behaviour. (This notation should not be confused with the term "structural dynamics" in the context of Finite Element Simulation). Continuous systems with structural dynamics  or so called "hybrid systems"  can often be investigated only by a socalled "hybrid simulation" which means a simultaneous simulation of continuoustime dynamics (modelled by differential equations or differentialalgebraic equations (DAE) and discreteevent dynamics (modelled e.g. by Boolean equations, finite state machines, or statecharts). To this end, an algorithm for numerical simulation of hybrid systems must be able to both solve a DAE system within a "continuous" time progression as well as to deal with eventdriven phenomena.
In the paper, the point of view is emphasized that the structure of a continuous system is closely combined to the structure of the DAE system which describes the continuous system's dynamical behaviour. In this context, discretetime events are considered as phenomena which may cause a change of the DAE system's structure. Furthermore, a distinction between systems with variable structure and models with variable structure is explained. The main part of the paper deals in detail with a simulation algorithm suitable for hybrid systems. This algorithm consists of a "continuous phase" (for numerical integration of the DAE system) and a "discrete phase" (for interpreting the event, establishing the new valid DAE system, calculating the new initial values). Some simulation results dealing with selected models and using the multiphysics language Modelica will complete the paper.