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Discontinuities handled with events in Assimulo, a practical approach

Fredriksson, Emil LU (2013) In Master's Theses in Mathematical Sciences FMN820 20131
Mathematics (Faculty of Engineering)
Abstract
Often ordinary differential equations or differential algebraic equations do not constitute the problem alone. A common complement is finding the root of an algebraic function (an event function) that depends on the states of the problem. This formulation of a model enables the possibility of including discontinuities and saving or stopping the process more effective. The problem of root-finding during integration is however difficult. Both in a theoretical aspect and as a software problem. In this thesis, the theoretical aspects are made with emphasis on explicit ordinary differential equations and the implementation of software is done in Assimulo. It takes into consideration the existing structures and the Functional Mockup Interface... (More)
Often ordinary differential equations or differential algebraic equations do not constitute the problem alone. A common complement is finding the root of an algebraic function (an event function) that depends on the states of the problem. This formulation of a model enables the possibility of including discontinuities and saving or stopping the process more effective. The problem of root-finding during integration is however difficult. Both in a theoretical aspect and as a software problem. In this thesis, the theoretical aspects are made with emphasis on explicit ordinary differential equations and the implementation of software is done in Assimulo. It takes into consideration the existing structures and the Functional Mockup Interface standard. The implementation is made usable for a wide variety of solvers and is also verified and benchmarked with advanced industrial models, showing good indications of being robust and scaling well for large systems. (Less)
Please use this url to cite or link to this publication:
author
Fredriksson, Emil LU
supervisor
organization
course
FMN820 20131
year
type
H2 - Master's Degree (Two Years)
subject
keywords
ODE, DAE, event, Assimulo, JModelica, Discontinuities, FMI, Functional Mockup Interface, differential equations, Root-finding, safeguard
publication/series
Master's Theses in Mathematical Sciences
report number
LUTFMA-30245-2013
ISSN
1404-6342
other publication id
2013:E38
language
English
id
4173087
date added to LUP
2014-02-14 16:26:55
date last changed
2015-12-14 13:32:11
@misc{4173087,
  abstract     = {Often ordinary differential equations or differential algebraic equations do not constitute the problem alone. A common complement is finding the root of an algebraic function (an event function) that depends on the states of the problem. This formulation of a model enables the possibility of including discontinuities and saving or stopping the process more effective. The problem of root-finding during integration is however difficult. Both in a theoretical aspect and as a software problem. In this thesis, the theoretical aspects are made with emphasis on explicit ordinary differential equations and the implementation of software is done in Assimulo. It takes into consideration the existing structures and the Functional Mockup Interface standard. The implementation is made usable for a wide variety of solvers and is also verified and benchmarked with advanced industrial models, showing good indications of being robust and scaling well for large systems.},
  author       = {Fredriksson, Emil},
  issn         = {1404-6342},
  keyword      = {ODE,DAE,event,Assimulo,JModelica,Discontinuities,FMI,Functional Mockup Interface,differential equations,Root-finding,safeguard},
  language     = {eng},
  note         = {Student Paper},
  series       = {Master's Theses in Mathematical Sciences},
  title        = {Discontinuities handled with events in Assimulo, a practical approach},
  year         = {2013},
}