Conference article

Mass Conserving Models of Vapor Compression Cycles

Christopher Laughman
Mitsubishi Electric Research Laboratories, USA

Hongtao Qiao
Mitsubishi Electric Research Laboratories, USA

Download articlehttp://dx.doi.org/10.3384/ecp15118759

Published in: Proceedings of the 11th International Modelica Conference, Versailles, France, September 21-23, 2015

Linköping Electronic Conference Proceedings 118:81, s. 759-767

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Published: 2015-09-18

ISBN: 978-91-7685-955-1

ISSN: 1650-3686 (print), 1650-3740 (online)

Abstract

Many dynamic models of vapor compression systems experience nonphysical variations in the total refrigerant mass contained in the system when common modeling approaches are used. Ratherthan use the traditional state variables of pressure and specific enthalpy, the use of density as a state variable can eliminate these variations. A set of test models is developed in Modelica to study the effect of the state variable selection on the overall system charge, and results indicate that this alternative approach has significant benefits for maintaining a specified mass of refrigerant in the cycle.

Keywords

vapor compression cycle; simulation; mass conservation

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