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Title: Tuning the heat transfer medium and operating conditions in magnetic refrigeration

Abstract

A new experimental test bed has been designed, built, and tested to evaluate the effect of the system’s parameters on a reciprocating Active Magnetic Regenerator (AMR) near room temperature. Bulk gadolinium was used as the refrigerant, silicon oil as the heat transfer medium, and a magnetic field of 1.3 T was cycled. This study focuses on the methodology of single stage AMR operation conditions to get a high temperature span near room temperature. Herein, the main objective is not to report the absolute maximum attainable temperature span seen in an AMR system, but rather to find the system’s optimal operating conditions to reach that maximum span. The results of this research show that there is a optimal operating frequency, heat transfer fluid flow rate, flow duration, and displaced volume ratio in any AMR system. By optimizing these parameters in our AMR apparatus the temperature span between the hot and cold ends increased by 24%. The optimized values are system dependent and need to be determined and measured for any AMR system by following the procedures that are introduced in this research. It is expected that such optimization will permit the design of a more efficient magnetic refrigeration system.

Authors:
 [1];  [2]; ; ; ;  [3]
  1. Dept. of Computer Science, Mathematics, and Engineering, Shepherd University, Shepherdstown WV 25443 (United States)
  2. (United States)
  3. Dept. of Electrical and Computer Engineering, The George Washington University, Washington DC 20052 (United States)
Publication Date:
OSTI Identifier:
22611430
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 6; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; DESIGN; FLOW RATE; FLUID FLOW; GADOLINIUM; HEAT TRANSFER; HEAT TRANSFER FLUIDS; MAGNETIC FIELDS; OILS; OPTIMIZATION; REFRIGERANTS; REFRIGERATION; REGENERATORS; SILICON; TEMPERATURE RANGE 0273-0400 K

Citation Formats

Ghahremani, Mohammadreza, E-mail: mghahrem@shepherd.edu, Dept. of Electrical and Computer Engineering, The George Washington University, Washington DC 20052, Aslani, Amir, Siddique, Abid, Bennett, Lawrence H., and Della Torre, Edward. Tuning the heat transfer medium and operating conditions in magnetic refrigeration. United States: N. p., 2016. Web. doi:10.1063/1.4960379.
Ghahremani, Mohammadreza, E-mail: mghahrem@shepherd.edu, Dept. of Electrical and Computer Engineering, The George Washington University, Washington DC 20052, Aslani, Amir, Siddique, Abid, Bennett, Lawrence H., & Della Torre, Edward. Tuning the heat transfer medium and operating conditions in magnetic refrigeration. United States. doi:10.1063/1.4960379.
Ghahremani, Mohammadreza, E-mail: mghahrem@shepherd.edu, Dept. of Electrical and Computer Engineering, The George Washington University, Washington DC 20052, Aslani, Amir, Siddique, Abid, Bennett, Lawrence H., and Della Torre, Edward. 2016. "Tuning the heat transfer medium and operating conditions in magnetic refrigeration". United States. doi:10.1063/1.4960379.
@article{osti_22611430,
title = {Tuning the heat transfer medium and operating conditions in magnetic refrigeration},
author = {Ghahremani, Mohammadreza, E-mail: mghahrem@shepherd.edu and Dept. of Electrical and Computer Engineering, The George Washington University, Washington DC 20052 and Aslani, Amir and Siddique, Abid and Bennett, Lawrence H. and Della Torre, Edward},
abstractNote = {A new experimental test bed has been designed, built, and tested to evaluate the effect of the system’s parameters on a reciprocating Active Magnetic Regenerator (AMR) near room temperature. Bulk gadolinium was used as the refrigerant, silicon oil as the heat transfer medium, and a magnetic field of 1.3 T was cycled. This study focuses on the methodology of single stage AMR operation conditions to get a high temperature span near room temperature. Herein, the main objective is not to report the absolute maximum attainable temperature span seen in an AMR system, but rather to find the system’s optimal operating conditions to reach that maximum span. The results of this research show that there is a optimal operating frequency, heat transfer fluid flow rate, flow duration, and displaced volume ratio in any AMR system. By optimizing these parameters in our AMR apparatus the temperature span between the hot and cold ends increased by 24%. The optimized values are system dependent and need to be determined and measured for any AMR system by following the procedures that are introduced in this research. It is expected that such optimization will permit the design of a more efficient magnetic refrigeration system.},
doi = {10.1063/1.4960379},
journal = {AIP Advances},
number = 7,
volume = 6,
place = {United States},
year = 2016,
month = 7
}
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