牛津型斯特林制冷机的动力特性分析

为了提高牛津型斯特林制冷机的制冷效率,提出了一种应用数值软件进行动力特性研究的方法。总结分析了压缩机、膨胀机的板弹簧刚度和活塞质量,充气压力,膨胀机位移相位角,膨胀机活塞行程以及制冷温度对制冷机动力特性的影响规律。优化了制冷机的动力系统,实验验证了该方法的可行性。研究结果表明,优化后制冷机的压缩机电机效率和整机效率均有所提高。     

斯特林型脉冲管制冷机中压缩机与冷指耦合实验研究

从理论上分析了质量流和压力波对脉冲管制冷机中冷指和压缩机耦合的影响, 针对1台6 W/95 K斯特林型脉冲管制冷机行了具体研究.实验分析表明:只有当线性压缩机能够提供脉冲管冷指所需的压力波动和质量流量时,整机才可能取得较好的性能;运行频率和整机的输入功率对压缩机效率的影响都小于2%.     

直线驱动斯特林制冷机可靠性失效分析

论述了直线电机驱动战术斯特林制冷机可靠性失效的4种模式,总结了25台1.5 W/80 K斯特林制冷机中的9台在可靠性增长过程中曾经出现的故障情况,分析了这9台制冷机可靠性失效原因,从而针对性提出了可靠性增长的解决措施.试验表明不同的可靠性试验方法反映不同的失效模式.     

斯特林制冷机关键材料的出气特性分析

长寿命制冷机性能退化的主要原因之一是内部工质污染,了解所用材料的出气特性至关重要。测试了制冷机内部6种关键材料的出气特性,其主要出气成分为水、邻苯二甲酸酯、烷烃等。基于相关理论,建立了关键材料的出气特性模型,对制冷机关键材料的选择、除气工艺的优化、污染失效模式的控制有参考价值。     

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...     

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.     

斯特林制冷机的热力性能

分析了文献中所存在的问题，并在文献的基础上研究了斯特林制冷机的热力性能。     

氖气斯特林制冷机的固有非理想回热特性

氖气斯特林制冷机具有正的固有非理想回热特性,它既使制冷机的理论制冷系数比卡诺制冷系数ε_c小,又使理论制冷量比工质在低温等温过程中所吸取的热量Q_L小,很值得注意。尤其在精度要求较高的场合,更不能不加考虑。     

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.     

空间用斯特林制冷机的寿命评价

介绍了空间用斯特林制冷机的主要失效模式和失效机理,国内外寿命评价研究的状况和进展,分析了几种加速寿命评价方法.针对中国空间用制冷机寿命评价研究的现状,提出了加速寿命评价的一些见解和思路.     

斯特林型两级脉管制冷机的改进

在最近研制的1台直线压缩机驱动的两极脉管制冷机的初步试验的基础上,对直线压缩机的线圈重新进行了设计和制作,解决了由于绕制圈数过多而无法输入足够电功率的问题。对冷头的热端法兰及回热器热端热交换器进行了改进,采用了微槽式水冷却器,解决了压缩热无法得到充分冷却引起的制冷机热端温度过高的问题。改进后制冷机的性能得到了显著的提高,在2.0 MPa充气压力和40 Hz频率的条件下,该制冷机获得了14.2 K的最低制冷温度。并且,第一级和第二级在97.8 K和34.9 K时,分别具有2.5 W和1 W的制冷量。     

空间斯特林制冷机失效分析

针对空间用的"牛津型"斯特林制冷机的结构特点,对其早期失效模式和正常失效模式等主要失效模式进行了较深入分析,提出了改进措施.通过结构设计、工艺等改进,可以消除早期失效模式、延长正常失效的时间.     

双级斯特林制冷机热力分析

基于热力学第一定律,分析了双级斯特林制冷机两级之间冷量分配的关系式,以及冷量与压缩机功耗之间的关系.通过商业计算软件,对制冷机内部能量流进行模拟计算,结合实例定量给出制冷机各部分的损失.     

斯特林制冷机的自寻优前馈振动控制

研究采用自寻优前馈方案实现斯特林制冷机的主动减振。斯特林制冷机是提供空间大制冷量的最佳手段。从减轻重量、减小体积和功耗的角度出发,提出了一种基于前馈控制的主动减振方案,用直线电机推动一个质量平衡块以抑制制冷机的振动,并设计了控制器参数的在线自寻优算法,实现整套系统的全自动运行。该减振系统的控制算法由DSP实现,将制冷机的基频振动水平降低到原来的2.87%。     

冷头温度对新型气动分置式斯特林制冷机运行性能影响的研究

介绍了气动分置式斯特林制冷机性能实验样机的组成、主要结构参数和试验结果，并对试验结果进行了分析，在新型气动分置式斯特林制冷机运行中，冷头起着进行负反馈调节的桥梁作用。     

15 K two-stage Stirling-type pulse-tube cryocooler

A two-stage pulse-tube cryocooler driven by a linear compressor was designed, manufactured and tested. The compressor is a moving-magnet type and dual-opposed-piston configuration, in which a plate spring is used. The two-stage cold head is a gas-separating thermal-link configuration. The phase shifter of each stage of the cryocooler can be double-inlet or inertance-tube type. Experiments have been carried out. The linear compressor can provide a pressure ratio of 1.3-1.5. Under the conditions of 1.2 MPa charging pressure and 32 Hz frequency, the second stage of the cryocooler reached a lowest temperature of 14.2 K, and the corresponding cooling temperature of the first stage is 93.3 K.     

Numerical analysis on performance and contaminated failures of the miniature split Stirling cryocooler

A mathematical model based on thermodynamic theory of variable mass is developed for the split Stirling refrigerator, in which, the whole machine is considered by one-dimensional approach while the processes in the regenerator are simulated by two-dimensional approach. First, the influence of the ideal frost layer distributions on the flow and heat transfer in the regenerator and the performance of the Stirling cryocooler are simulated. Then, the distribution of the contaminated water vapor and its coagulated and deposited process is qualitatively analyzed. Finally, the lifetime of the refrigerator is evaluated based on the calculated data. The results show that when the refrigerator is operated at uniform distribution of the water vapor partial pressure in the regenerator, the cooling capacity is reduced over 10% at about 631 h, and the power consumption of compressor is increased over 20% at about 1168 h. However, for the linear distribution of water vapor partial pressure, the refrigerator can work properly because the frost never reaches the criterion of failure. Also, it is found that when the Stirling cryocooler restarts after a shutdown, the cooling capacity is reduced by 10% once the frost mass is over 7.05 mg, and there is no cooling capacity once the frost mass reaches 41.2 mg.