Article | Proceedings of the 9th International MODELICA Conference; September 3-5; 2012; Munich; Germany | Natural Unit Representation in Modelica

Title:
Natural Unit Representation in Modelica
Author:
Kevin L. Davies: Georgia Institute of Technology, Atlanta, Georgia USA Christiann J. J. Paredis: Georgia Institute of Technology, Atlanta, Georgia USA
DOI:
10.3384/ecp12076801
Download:
Full text (pdf)
Year:
2012
Conference:
Proceedings of the 9th International MODELICA Conference; September 3-5; 2012; Munich; Germany
Issue:
076
Article no.:
082
Pages:
801-808
No. of pages:
8
Publication type:
Abstract and Fulltext
Published:
2012-11-19
ISBN:
978-91-7519-826-2
Series:
Linköping Electronic Conference Proceedings
ISSN (print):
1650-3686
ISSN (online):
1650-3740
Publisher:
Linköping University Electronic Press; Linköpings universitet


A method is presented by which alternative systems of physical units may be represented and utilized in Modelica. The method may be useful in simulating models of physical systems where the base units of the International System of Units (SI)--the standard unit system in Modelica--are poorly scaled. It also provides a convenient means to express the values of physical quantities in fields of science and engineering where data is typically represented in other systems of units or constants (i.e.; "natural units"). By explicitly expressing the value of a physical quantity as the product of a number and a unit (where the unit is an algebraic variable); the method uses variables that are unit-neutral. Unfortunately; workarounds are necessary in order to implement the method in the current version of the Modelica language. Nonetheless; it may be useful in special applications; and the related discussion may provide valuable insight. In particular; it is shown that there is an apparent conflict in the interpretation of "number" and "value" between Modelica and the International Bureau of Weights and Measures (BIPM).

Keywords: natural units; physical quantities; Modelica; SI

Proceedings of the 9th International MODELICA Conference; September 3-5; 2012; Munich; Germany

Author:
Kevin L. Davies, Christiann J. J. Paredis
Title:
Natural Unit Representation in Modelica
DOI:
10.3384/ecp12076801
References:
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Proceedings of the 9th International MODELICA Conference; September 3-5; 2012; Munich; Germany

Author:
Kevin L. Davies, Christiann J. J. Paredis
Title:
Natural Unit Representation in Modelica
DOI:
10.3384/ecp12076801
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