Conference article

Modeling of a Thermosiphon to Recharge Phase Change Material Based Thermal Battery for a Portable Air Conditioning Device

Rohit Dhumane
Center for Environmental Energy Engineering, University of Maryland, College Park, 4164 Glenn L. Martin Hall, Bldg., MD 20742, USA

Jiazhen Ling
Center for Environmental Energy Engineering, University of Maryland, College Park, 4164 Glenn L. Martin Hall, Bldg., MD 20742, USA

Vikrant Aute
Center for Environmental Energy Engineering, University of Maryland, College Park, 4164 Glenn L. Martin Hall, Bldg., MD 20742, USA

Reinhard Radermacher
Center for Environmental Energy Engineering, University of Maryland, College Park, 4164 Glenn L. Martin Hall, Bldg., MD 20742, USA

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Published in: Proceedings of the 12th International Modelica Conference, Prague, Czech Republic, May 15-17, 2017

Linköping Electronic Conference Proceedings 132:52, p. 459-465

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Published: 2017-07-04

ISBN: 978-91-7685-575-1

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


Closed loop two phase thermosiphons have a wide range of applications due to their simplicity, reliability, low cost and the ability of dissipating high heat fluxes from minimal temperature differences. The present study focuses on one thermosiphon operation which solidifies a phase change material (PCM) based thermal battery for a portable air conditioner called Roving Comforter (RoCo). RoCo uses vapor compression cycle (VCC) to deliver cooling and stores the heat released from the condenser into a compact phase change material (PCM) based thermal battery. Before its next cooling operation, the PCM needs to be re-solidified. This is achieved by the thermosiphon, which operates within the same refrigerant circuitry with the help of a pair of valves. The molten PCM which acts as heat source affects the dynamics of the thermosiphon which in turn affects the solidification process. Thus the dynamics of both the PCM and thermosiphon are coupled. For accurate transient modeling of this process, the PCM model considers the solidification over a temperature range, variable effects of conduction and natural convection during the phase change and variable amounts of heat release at different temperatures within the temperature range of phase change. The paper discusses component modeling for this transient operation of thermosiphon and its validation with experimental data.


Thermosiphon, Thermosyphon, Phase Change Materials


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