TECHNISCHE UNIVERSITÄT BERLIN A Combined Structural-Algebraic Approach for the Regularization of Coupled Systems of DAEs
نویسندگان
چکیده
The automated modeling of multi-physical dynamical systems is usually realized by coupling different subsystems together via certain interface or coupling conditions. This approach results in large-scale high-index differential-algebraic equations (DAEs). Since the direct numerical simulation of these kind of systems leads to instabilities and possibly non-convergence of the numerical methods a regularization or remodeling of the system is required. In many simulation environments a kind of structural analysis based on the sparsity pattern of the system is used to determine the index and a reduced system model. However, this approach is not reliable for certain problem classes, in particular we show that it is not suited for coupled systems of DAEs. We will present a new approach for the regularization of coupled dynamical systems that combines the structural analysis, in particular the Signature Method [11], with classical algebraic regularization techniques and thus allows to handle so-called structurally singular systems and also enables a proper treatment of redundancies or inconsistencies in the system.
منابع مشابه
Technische Universität Berlin Institut für Mathematik Regularization and Numerical Simulation of Dynamical Systems Modeled with Modelica
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