60~80 K温区主动磁回热器性能影响因子的数值模拟研究  

Numerical Simulation of Performance Influencing Factors of Active Magnetic Regenerators in the Temperature Range of 60~80 K

作　　者：郑文帅 李振兴[1,2,3] 李珂 海鹏[1,3] 黄红梅 戴巍[1,2] 沈俊 ZHENG Wenshuai;LI Zhenxing;LI Ke;HAI Peng;HUANG Hongmei;DAI Wei;SHEN Jun(Key Laboratory of Cryogenics,Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China;Ganjiang Innovation Academy,Chinese Academy of Sciences,Ganzhou 341119,China)

机构地区：[1]中国科学院理化技术研究所低温工程学重点实验室,北京100190 [2]中国科学院大学,北京100049 [3]中国科学院赣江创新研究院,赣州341119

出　　处：《工程热物理学报》2022年第11期2904-2913,共10页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.51925605);中国科学院低温工程学重点实验室(No.CRYOQN202102);中国科学院科研仪器设备研制项目(No.YJKYYQ20200076);中国博士后科学基金资助项目(No.2021T140681)。

摘　　要：基于液氮至液氢温区的多级主动磁制冷流程设计,本文借助COMSOL多物理场耦合软件,构建了60∼80 K温区二维瞬态主动磁回热器模型,分别开展了假想材料与实际材料DyFeSi的数值仿真研究。首先,基于恒定磁熵变5.4 J·kg^(−1)·K^(−1)的假想材料,对比分析了磁热工质颗粒直径、回热器长径比与填充质量对磁制冷性能的影响。仿真结果表明,随着磁热工质颗粒直径的增大(0.2∼0.7 mm),主动磁回热器的制冷量减小,且随着氦气质量流量增加(2∼18 g·s^(−1)),主动磁回热器的最优颗粒直径减小;随着回热器长径比增大,制冷量逐渐增大,COP在长径比为5时取得较优值;主动磁回热器的最大制冷量与工质填充质量呈线性增加的关系。随后,以优化后的几何参数(颗粒直径0.4 mm、长径比5)开展了实际工质DyFeSi填充的主动磁回热器性能研究。当质量流量为4.5 g·s^(−1)时,主动磁回热器取得最大制冷量1.5 W,对应的热力学第二效率为28.67%。尽管单一种类的实际工质难以在60∼80 K温区中获得较好的制冷量与制冷效率,本文所开展的研究对于高温级主动磁回热器的多层结构设计具有重要的参考价值与指导意义。In this paper,based on the multi-stage active magnetic refrigeration process from liquid nitrogen temperature to liquid hydrogen temperature,a two-dimensional transient active magnetic regenerator model in the temperature range of 60~80 K has been built by means of COMSOL Multiphysics 5.5.And the simulation optimization research of ideal and real magnetocaloric materials was carried out.First,based on the ideal magnetocaloric material with magnetic entropy change of 5.4 J·kg^(−1)·K^(−1),the effects of various factors in the regenerator on the performance of magnetic refrigeration were compared and analyzed,including the particle diameter of the magnetocaloric material,the regenerator aspect ratio,and filling quality of magnetocaloric material.The simulation results showed that the cooling power of the active magnetic regenerator decreased with the increase of the particle diameter of the magnetocaloric material(0.2~0.7 mm).Furthermore,as the mass flow rate of helium increased(2~18 g·s^(−1)),the optimal particle diameter of the active magnetic regenerator decreased;With the increase of regenerator aspect ratio,the cooling power gradually increased,and a greater COP was achieved when the regenerator aspect ratio was 5;The relationship between the maximum cooling power of the active magnetic regenerator and the filling quality of magnetocaloric material increases linearly.Then,based on the optimized geometric parameters(particle diameter was 0.4 mm and aspect ratio was 5),the performance of the active magnetic regenerator filled with real magnetocaloric materials DyFeSi was studied.When the mass flow rate was 4.5 g·s^(−1),the active magnetic regenerator obtained the maximum cooling power of 1.5 W,and the corresponding second thermodynamic efficiency was 28.67%.Although it was difficult for a kind of real magnetocaloric material to obtain better cooling power and cooling efficiency in the temperature range of 60~80 K,the research carried out in this paper has important reference value and guiding signific

关 键 词：氢液化 磁制冷 主动磁回热器 数值模拟 影响因子 

分 类 号：TB651[一般工业技术—制冷工程]