Introduction
- Typical error messages when simulating:
- Simulink
- Cannot solve algebraic loop ...
- Dymola
- Failed to reduce the DAE index.
- Possible causes:
- novice modeller: "bug in simulation programm"
- experienced modeller: "bug in own model"
- reality: mathematical problem in model
- Why mathematics fails:
- modeling needs simplification
- oversimplification
- → model becomes unphysical
- → mathematical description incomplete or
inconsistent
- Remedies:
- extend or fix mathematical description
- can lead to unphysical behaviour
- can be difficult to implement
- add physical details to model
- mathematical problems disappear
- but: model has (often lots of) new parameters