University of Twente, Dept. Thermal and Fluid Engineering

摘要：

Magnetic refrigeration is considered as a potential alternative to vapour compression refrigeration technology due to its relatively higher energy efficiency and its use of environment-friendly materials. A magnetocaloric refrigerator with no moving parts offers higher reliability for critical applications and lower vibration. For this a mixture of magnetocaloric material and heat transfer liquid as the refrigerant is considered. This mixture is circulated between hot and cold heat exchangers using a ferrohydrodynamic pump, while the permanent magnet is stationary. It is analysed by first considering the ferrohydrodynamic pump design, followed by material analysis of the mixture, and finally a system level analysis of the refrigerator. For the ferrohydrodynamic pump, a novel design that achieves the same normalized mass flow rate as the state-of-the-art, but at three orders of magnitude lower frequencies is experimentally tested and numerically characterized.  For the material analysis, La(Fe,Mn,Si)13Hz with Ga-In-Sn liquid metal is considered owing to the favourable thermal and fluid properties of the latter, and their compatibility over 1.5 years is analysed.  Finally, numerical analysis on the system level performance is performed for different heat transfer fluid, volume fraction of magnetocaloric material, mass flow rate of the mixture, while their cooling power and second-law efficiency are determined.

地点：物理所M255

邀请人：胡凤霞

联系人：王晶（82649251）