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dc.contributor.authorEngelbrecht, Kurten_US
dc.date.accessioned2007-05-14T14:40:07Z
dc.date.available2007-05-14T14:40:07Z
dc.date.issued2005en_US
dc.identifier.citationEngelbrecht, K. (2005). A Numerical Model of an Active Magnetic Regenerator Refrigeration System. Master's Thesis, University of Wisconsin-Madison.en_US
dc.identifier.urihttp://digital.library.wisc.edu/1793/7596
dc.descriptionUnder the supervision of Professors Gregory F. Nellis and Sanford A. Klein.en_US
dc.description.abstractActive magnetic regenerator refrigeration (AMRR) systems are an environmentally attractive space cooling and refrigeration alternative that do not use a fluorocarbon working fluid. Two recent developments have made AMRRs appear possible to implement in the near-term. A rotary regenerator bed utilizing practical and affordable permanent magnets has been demonstrated to achieve acceptable COP. Concurrently, families of magnetocaloric material alloys with adjustable Curie temperatures have been developed. Using these materials it is possible to construct a layered regenerator bed that can achieve a high magnetocaloric effect across its entire operating range, resulting in an improved COP. There is currently no tool capable of predicting the performance of a layered AMRR. This project provides a numerical model that predicts the practical limits of these systems for use in space conditioning and refrigeration applications. The model treats the regenerator bed as a one dimensional matrix of magnetic material with a spatial variation in Curie temperature and therefore magnetic properties. The matrix is subjected to a spatially and temporally varying magnetic field and fluid mass flow. The variation of these forcing functions is based on the implementation of a rotating, multiple bed configuration. The numerical model is solved using a fully implicit (in time and space) discretization of the governing energy equations. The nonlinear aspects of the governing equations (e.g., fluid and magnetic property variations) are handled using a relaxation technique. The model is used to optimize AMRR applications by varying model inputs such as matrix material, fluid mass flow rate, working fluid, reservoir temperatures, and the variation of the Curie temperature across the bed. The preliminary model has been verified qualitatively using simple cycle parameters and constant property materials and quantitatively by comparing the results with prior solutions to the regenerator governing equations in the limits of constant properties and no magnetocaloric effect. A second goal of this project is to create a cost estimate for a future project that will design, build, and test a prototype AMRR to be used to verify the numerical model.en_US
dc.description.sponsorshipSponsored by the Air Conditioning and Refrigeration Institute.en_US
dc.format.extent2551334 bytes
dc.format.mimetypeapplication/pdfen_US
dc.format.mimetypeapplication/pdf
dc.publisherUniversity of Wisconsin-Madisonen_US
dc.subjectThesis (M.S.)--University of Wisconsin--Madison, 2005.en_US
dc.subjectDissertations Academic Mechanical Engineering.en_US
dc.subjectUniversity of Wisconsin--Madison. College of Engineering.en_US
dc.titleA Numerical Model of an Active Magnetic Regenerator Refrigeration Systemen_US


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