2025-09-10 –, 202
The convergence failure of iterative Newton solvers during the initialization of Modelica models is a serious show-stopper, particularly for inexperienced users. This paper presents the implementation in the OpenModelica tool of methods presented by two of the authors in a previous paper, to help diagnosing and resolving these convergence failure by providing ranked lists of potentially critical start attributes that might need to be fixed in order to successfully achieve convergence. The method also provides library developers with useful information about critical nonlinear equations, that could be replaced by equivalent, less nonlinear ones, or approximated by homotopy for more robust initialization.
Francesco Casella is associate professor at Politecnico di Milano. His main research interests are modelling and control of innovative thermal power generation systems, Modelica modelling of engineering systems in general, and advanced numerical and symbolic methods for Modelica model simulation. He is the Director of the Open Source Modelica Consortium, member of the Board of the Modelica Association, and an active member of the Modelica community since 2003.
- PhD student at the University of Bielefeld
- Scientific staff member in the Department of Engineering Sciences and Mathematics at Hochschule Bielefeld (Bielefeld University of Applied Sciences).
- Backend Developer for OpenModelica
- He holds a Master of Science degree from the same institutionin Optimization and Simulation.
- At Hochschule Bielefeld, he has been contributing continuously since around January 2019, engaging in both teaching and research activities.
- Professor of Mathematics and Technical Applications, Bielefeld University of Applied Sciences (HSBI, since 1999)
- Research focus: numerical mathematics, nonlinear optimization, symbolic and numerical methods for large hybrid differential-algebraic systems
- Founding member of the Modelica Association (1996) and Open Source Modelica Consortium (2004)
- Key contributions to the BackEnd and C-Runtime of the OpenModelica Compiler
- Co-Author of the Modelica Petri Net Library and Modelica Neural Network Library
- Research stays at ABB Research Center (Switzerland, USA, Sweden), Linköping University (Sweden), and Politecnico di Milano (Italy)
- Member, Promotionskolleg NRW (since 2022)
- Founding board member, Institute for Data Science Solutions (IDaS), HSBI (since 2022)