Design And Study On The Room Temperature Magnetic Refrigerator

The magnetic refrigeration is based on the magneto-caloric effect (MCE). MCE is aphenomenon that a magnetic material releases heat when it is magnetized and absorbs heatwhen it is demagnetized. Magnetic refrigeration has been become one of the research focusesin cooling area due to its high-efficiency, energy-conservation, and environment-friendlinesscompared with the traditional gas compression refrigeration, which can help reaching the goalof low carbon economy advocated in the modern world and has broad application prospects.The room temperature magnetic refrigeration technology is predicted to have the extensiveapplications in the fields of home refrigerator, automobile air conditioning, food industry, andhealth, etc. Therefore, the prospect of magnetic refrigeration technology is promising.The main works in this paper include: a reciprocating room temperature magneticrefrigerator was assembled and tested, which results, in turn, improve the following designs; adouble air gap permanent magnetic field with specific structure was designed, using theANSYS software which is a kind of finite element simulation software that can calculatemagnetic field; a new moving model room temperature magnetic refrigerator--a swing roomtemperature magnetic refrigerator was propounded; the distribution of the active regeneratorinternal velocity field was simulated by using fluid simulation software FLUENT, and theresults were analyzed and discussed. The main results are as follows:â'ˆOn the basis of the former works of our group, a reciprocating magnetic refrigeratorat room temperature has been assembled, debugged and tested. The testing results show that,when the heat exchanger flow rate is0.30m/s, the maximum temperature drop can reach1.8K, which just reaches an initial cooling effect. There are many factors to influence the coolingefficiency, such as manufacturing, assembly techniques, as well as the reciprocatingmovement itself limits the operating frequency; the measured magnetic field strength is low(only0.7T); poor insulation effect; the heat leakage of the magnetized is large, the heattransfer technology is imperfect.â'‰Analyzed the requirements and problems of the magnetic field for room temperaturemagnetic refrigerator, a double air gap permanent magnet has been designed by using ANSYS 11.0analysis software. The magnet has the following characteristics: large magnetic fieldstrength (reach to1.2T) and uniform magnetic field; because of the dual air gap is large, itcan hold much more magnetic refrigerant (e.g. for Gd, theoretically up to3.1kg); thesymmetrical structure can greatly reduced axial force.â'ŠA new moving model room temperature magnetic refrigerator--―a swing roomtemperature magnetic refrigerator‖is propounded. Due to its special swing movement style,the magnetic refrigerator not only has the advantages of a simple reciprocating structure, butalso has the advantages of rotary magnetic refrigerator high efficiency.â'‹Molded and simulated internal velocity field distribution in the active regeneratorswhich have different inlet and outlet configuration by Fluent analysis software. The ipsilateralopenings active regenerator can help obtain a higher cooling temperature span.