10W@77K自由活塞斯特林制冷机的设计和实验研究

为满足高温超导、红外探测和气体液化等领域对高效率、高可靠性、长寿命低温制冷机的需求,对10W@77K自由活塞斯特林制冷机进行了研究.制冷机设计为整体式结构,由动磁式直线电机驱动.基于Sage建立制冷机整机模型开展了数值求解,并根据数值计算结果对运行频率、工作压力以及回热器填料等对制冷机性能的影响规律进行了分析.计算结果...     

6 W@90 K星载斯特林制冷机的热环境适应性

针对某空间任务要求,分析了热试验温度取值.基于1台6 W@90 K星载斯特林制冷机,开展了常压热循环和热真空试验研究,得到了制冷机在不同温区下的制冷性能参数.从6个方面对比分析了两个试验中性能参数的变化,最后得出:环境温度对6 w制冷机性能影响较大,从50 ℃到-20℃温区,制冷温度为90 K时,冷量增大约1.4 W,功耗减小约17 W;在50至-20℃温区内,制冷机未发生结构热变形失效.该6 W型制冷机在合理设计辅助散热(卫星总体热控调节)之后,可满足空间应用时-20℃-40 ℃温区热环境适应性;压缩机和膨胀机通过良导热体连接散热,可平衡温差,便于控温.     

斯特林制冷机混合填料回热器性能优化及试验研究

针对旋转整体式斯特林制冷机的回热器性能优化,讨论了回热器丝网填料选型的原则,分析了不同温区采用不同丝网参数的回热器模型,并利用REGEN软件对混合丝网模型进行了优化分析。通过实验数据对模拟优化的结果进行了分析和讨论,验证了混合丝网模型优化结果的正确性,为旋转整体式斯特林制冷机回热器性能优化提供依据。     

5W@80K自由活塞斯特林制冷机工况及重力特性实验研究

利用现有的脉冲管制冷机性能测试实验台,针对某型号自由活塞斯特林制冷机,设计了热端水冷器并进行了性能测试.实验研究了工作频率、充气压力、输入功率等参数对制冷机性能的影响规律,结果表明斯特林制冷机的最佳运行工况为充气压力2.0 MPa,频率42 Hz.改变冷头在竖直方向和水平面不同的朝向,实验结果表明冷头竖直向下时最低制冷...     

微型斯特林制冷机发展综述

从电子技术和光电子技术发展背景出发,论述了微型斯特林制冷机的发展前景及其关键子系统(控制系统、驱动系统和回热器等)的发展情况;同时论述了高频微型斯特林制冷机发展的技术关键是回热器的孔径率很高或者是孔径很小(10～50μm),同时膜的振幅在10～100μm级,以减小高频下黏性损失有所增大的负效应。     

6W@80K气动分置式斯特林制冷机轻量化设计和性能优化

介绍了一台由中国科学院上海技术物理研究所研制的6 W@80 K气动分置式斯特林制冷机样机,主要包括压缩机的轻量化设计和整机制冷性能的优化。该制冷机包括动磁式直线压缩机和气动膨胀机,制冷机整机质量为5.5 kg。压缩机采用两个对置布置的动磁式直线电机驱动,板弹簧支撑和无摩擦的间隙密封技术。经过对直线压缩机的结构优化,在6 W@80 K的制冷性能下,压缩机的输入电功从原来的163 W降低到106 W。     

基于DSP的星载小型化斯特林制冷机控制器设计

斯特林制冷机控制器对制冷机性能有很大影响。介绍了基于DSP系统的斯特林制冷机控制器设计,主要包括硬件、软件设计,为进一步实现斯特林制冷机的自适应控制打下较好的基础。     

大功率斯特林制冷机的整机数值模拟

应用低温制冷机整机模拟软件(SAGE)对一台"3LY—0.8/194"型斯特林制冷机开展了数值模拟研究,得到质量流率、工质压力以及声功、焓流等参数的变化规律,揭示了制冷过程中内部能量流的耦合作用关系。此外,基于回热器内工质的温度分布分析,发现该制冷机的部分回热器未得到有效利用,从而为即将开展的改进实验研究提供了思路。模拟结果显示该制冷机可以达到37.5 K最低制冷温度,在77.35 K能够提供1 044 W制冷量,输入PV功为9 416 W,相对卡诺循环效率达到30.2%。     

80K/2W斯特林制冷机全性能实验研究

80 K/2 W斯特林制冷机是上海技术物理研究所自行研制的分置式牛津型制冷机.为验证斯特林制冷机在各种工况下的广泛适应性,针对80 K/2 W制冷机进行实验,测试制冷机在不同压缩机行程、制冷温度以及环境温度下的全性能特性,总结斯特林制冷机部分实用的规律.     

小型斯特林制冷机回热器理论模型与分析

对小型斯特林制冷机回热器建立理论模型,通过对控制方程进行无量纲化处理及合理简化,推导出表征小型斯特林制冷机回热器不可逆性的熵流方程。     

The thermodynamic characteristics of a Stirling/pulse tube hybrid cryocooler

A Stirling/pulse tube hybrid cryocooler (SPC), comprised of a Stirling cryocooler as the first stage and a pulse tube cryocooler as the second stage, features the ability of shifting cooling capacity between stages by adjusting the movement of the displacer in the first stage. Such an ability allows an SPC to accommodate itself to time-varying heat loads at different temperatures, which makes it a competitive candidate in space applications. However, due to the gas coupling, there exists a significant mutual effect between stages which endows an SPC with special thermodynamic characteristics and has a significant effect on the SPC’s capability of shifting cooling capacity between stages. With the phasor analysis and the thermodynamic analysis, this paper establishes an idealized model of an SPC. The model is then used to study the effect of the second stage on the first stage and reveal the condition that an SPC is able to shift cooling capacity between stages. Also, the model is compared with a Sage numerical model and the two models are consistent on the overall trend. Though it is unable to reflect reality precisely, the idealized model can interpret the mechanism and highlight some of the essential nature of an SPC, which will eventually benefit the appropriate design of an SPC.     

Operating characteristics of a single-stage Stirling cryocooler capable of providing 700 W cooling power at 77 K

High cooling capacity Stirling cryocooler generally has hundreds to thousands watts of cooling power at liquid nitrogen temperature. It is promising in boil-off gas (BOG) recondensation and high temperature superconducting (HTS) applications. A high cooling capacity Stirling cryocooler driven by a crank-rod mechanism was developed and studied systematically. The pressure and frequency characteristics of the cryocooler, the heat rejection from the ambient heat exchanger, and the cooling performance are studied under different charging pressure. Energy conversion and distribution in the cryocooler are analyzed theoretically. With an electric input power of 10.9 kW and a rotating speed of 1450 r/min of the motor, a cooling power of 700 W at 77 K and a relative Carnot efficiency of 18.2% of the cryocooler have been achieved in the present study, and the corresponding pressure ratio in the compression space reaches 2.46.     

Performance improvement of a two-stage GM cryocooler by use of Er(Ni0.075Co0.925)2 magnetic regenerator material

A newly developed magnetic regenerator material Er(Ni_0.075Co_0.925)₂, having high specific heat at temperatures from 10 to 20 K, has been tested inside the second regenerator of a two-stage GM cryocooler. Different working conditions have been examined: four Er(Ni_0.075Co_0.925)₂/Pb material ratios, three displacer reciprocating speeds, and two cryocooler stroke lengths. In the best working conditions, the experimental results show a cooling power improvement up to 15% over the whole temperature range from 10 to 20 K compared to that of the same GM cryocooler employing only lead.     

DC流对液氦温区斯特林型脉管制冷机的影响

理论研究表明DC流(Direct Current flow)存在于大多数双向进气结构的脉管制冷机中。开展了10 K以下多级斯特林脉管的实验研究,考察了在液氦温区斯特林脉管内直流流动对制冷机性能影响的规律。在采用双向进气结构对DC流流向及流量适当控制时,制冷机性能得到明显提升,在8—7 K温区适当的DC流下冷端由7.42 K降低至7.16 K。     

10W/80K高频同轴脉冲管制冷机的实验性能

介绍了一款大冷量高频单级同轴脉冲管制冷机的基本结构、数值模拟和实验性能。其线性压缩机采用Redlich动磁式直线电机驱动,压缩活塞对置布置,使用板弹簧支撑和间隙密封技术,80 K温区工作时的电机效率在83%以上。膨胀机的蓄冷器和脉冲管为同轴型布置,这种结构使冷头与器件之间的耦合非常方便。使用数值软件对制冷机整机和调相部件进行数值模拟,并对模拟结果进行实验验证。对制冷机的运行频率和制冷性能进行实验研究,制冷机在210.3 W输入电功时能获得10 W/80 K的制冷性能,比卡诺效率为12.66%,运行频率为62 Hz,整机重量小于5.5 kg。