微型节流制冷器用翅片管换热器的数值模拟研究

A NUMERICAL STUDY OF THE PERFORMANCE OF A FINNED-TUBE HEAT EXCHANGER FOR A MINIATURE JOULE-THOMSON CRYOCOOLER

微型节流制冷器因其快速冷却、结构简单紧凑而被广泛的应用在红外探测器、超导量子干涉器件、热像仪等器件的冷却。微型节流制冷器性能的好坏则取决于翅片管换热器内的流动特性与传热特性。通过数值模拟对翅片管换热器的热力学性能进行研究,数值模拟结果很好的揭示了翅片管换热器内的热力学特性。在此基础上,对微型节流制冷器进行了优化分析,结果表明了质量流量和换热器长度对换热器效率及制冷器理论制冷量的影响。

Miniature Joule-Thomson cryocoolers have been widely used for rapid cooling of infrared detectors,cryosurgery probes,thermal cameras,and missile guidance homing systems,due to their special features of simple configuration,compact structure and rapid cooldown characteristics.The thermodynamic performance of the J-T refrigerator depends upon the hydraulic and heat transfer characteristics of the recuperative heat exchanger.database is used to account for the real gas effects.The thermodynamic characteristics of the finned-tube Heat Exchanger are well revealed,based on this,the optimization analysis of miniature J-T cryocooler is carried out.The influences of mass flow rate and the length of heat exchanger on the effectiveness of heat exchanger and the ideal cooling capacity are discussed in details.