共查询到19条相似文献,搜索用时 203 毫秒
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介绍最近研制的一台双向进气带第二小孔阀型二极脉管制冷机实验情况。该机采用计算机时序控制,脉管热端均处于室温。文中给出了二级脉管制冷机的基本结构尺寸以及试验结果;一级脉管达到45K;二级脉管无负荷最低制冷温度达到3.1K。能稳定,长期工作,讨论了制冷机性能的主要因素。 相似文献
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采用微机实时控制脉管冷机配气装置,可以灵活调节压力波频率和阀门启闭时间比,有可能获得更低的温度,更大的制冷量,使其性能接近G-M制冷机,在脉管制冷机结构参数相同的条件下,二阀与无阀脉管制冷机性能的对比实验表明,通过仔细的时序调节,有阀型脉管制冷机可获得更好的制冷性能。 相似文献
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本文建立了小孔型脉管制冷机实验台,通过测量制冷机中动态的压力、示功图、制冷温度和制冷量,研究了阀门开度对制冷过程的影响。多路旁通方案比常规小孔和双向进气方案获得更低的制冷温度,达到23.8K,且P-V功最小。随着小孔开度增大,压缩腔和脉管中压力的相位差增大,压缩腔中压比增大,而脉管中压比减小,P-V功增大。双向进气阀和多路旁通阀开度的影响恰好与小孔的影响相反,有利于制冷过程。 相似文献
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采用直流电机驱动的无阀压缩机,在双向气型脉管制冷机上取得了46.8K的无负荷制冷温度,对脉管制冷机的压力波进行了测试。在分析回热损失,脉管与回热器相位差等方面获得了一些有益的结果。 相似文献
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介绍了自行研制的二级脉管制冷机的基本结构。该机引入了新颖的第二小孔调相器,采用有阀压机驱动,通过自行研制的时序控制器和电磁阀由计算机进行实时控制,初步试验结果表明第一级和第二级的最后制冷温度分别为58K和11.3K。 相似文献
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介绍了采用定时器及计算机实时控制脉管制冷机进排气的两种实验装置,实现了脉管制冷机压力波频率的无级调节,并可灵活地调整占空比及压力波的相位差.进而,采用定时器控制装置对自行研制的双向进气型脉管制冷机进行进排气控制,获得了41K的无负荷制冷温度. 相似文献
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着重研究了操作频率对液氦温区脉管制冷机性能的影响,在实验和分析的基础上,明确了制冷温度、制冷量、制冷效率与工作效率之间的关系,并与4K G-M制冷机的情况进行比较,得出了一些有益的结论。通过频率优化,脉管制冷性能得以较大提高。在初步试验中,分别在1.2Hz和1.1Hz获得了30W@70K,500mW@4.2K以及20W@65K,590mW@4.2K的制冷量。同时还给出了脉管制冷湿度稳定性的测试结果。试验结果表明,研制的脉管制冷机温度波动均小于同类商品型4K GM制冷机及脉管制冷机。 相似文献
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空调压缩机驱动高效同轴脉冲管制冷系统 总被引:7,自引:1,他引:6
介绍了为实际应用而开发的低成本、高效率、长寿命的制冷系统:空调压缩机驱动的单级同轴脉冲管制冷机。实验获得了38.4K的最低温度,制冷量3W/50K,大于6W/80K,输入功率约620W,启动过程操作简单、降温快、运行稳定。 相似文献
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This paper introduces intermediate cooling by thermally attaching heat exchangers on the second stage pulse tube and regenerator in a commercial 4 K pulse tube cryocooler. Due to the large enthalpy flow in the 2nd stage pulse tube and regenerator, both intermediate heat exchangers on the pulse tube and regenerator can provide cooling capacities in the temperature range of 5–15 K without or with minor effect on the performance of the 4 K stage. Extracting cooling capacity from the pulse tube or regenerator reduces the 1st stage cooling performance in the present study. The joint intermediate heat exchanger on the pulse tube and regenerator has demonstrated promising results for applications. 相似文献
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热声驱动脉管制冷机通常采用直接或者长管耦合的方式,但是因为耦合后的发动机和制冷机难以达到最佳的工作状态,耦合长管的损失也比较大,因此整体效率较低。本文提出一种热声驱动脉管制冷机结构,利用谐振子耦合热声发动机和脉管制冷机,能够显著减小声功传递损失,提升整机效率。全文针对在900 K加热温度、80 K空气液化温区下的热声驱动脉管制冷机展开理论研究,首先分析了谐振子耦合机理,并对谐振子参数进行了优化设计;其次,研究了加热温度、制冷温度和机械阻尼对系统性能影响;最后,将谐振子耦合型与长管耦合型两种方式的热声驱动制冷机进行了对比分析。结果表明:在平均压力为3MPa,加热温度为900 K,制冷温度为80 K时,谐振子耦合的热声驱动制冷机可获得整机22.5%的效率,而长管耦合的热声驱动脉管制冷机获得11.6%的效率。 相似文献
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级间热桥的传热特性对于热耦合型多级脉管制冷机的制冷温度和制冷效率均具有重要影响。采用铜丝编织带和铜箔连接的3种热桥进行对比实验,研究了热桥的传热特性对热耦合二级Stirling型脉管制冷机性能的影响。采用改进后的热桥,以氦气作为工质,在总输入电功率为400W,以及优化的工作频率和充气压力条件下,热耦合二级Stirling型脉管制冷机实现了12.96K的无负荷制冷温度,并可同时在23.1K和100.8K分别提供0.4W和6W的制冷量。 相似文献
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《低温学》2018
A compact and high efficiency cooler working at liquid hydrogen temperature has many important applications such as cooling superconductors and mid-infrared sensors. This paper presents a two-stage gas-coupled pulse tube cooler system with a completely co-axial configuration. A stepped warm displacer, working as the phase shifter for both stages, has been studied theoretically and experimentally in this paper. Comparisons with the traditional phase shifter (double inlet) are also made. Compared with the double inlet type, the stepped warm displacer has the advantages of recovering the expansion work from the pulse tube hot end (especially from the first stage) and easily realizing an appropriate phase relationship between the pressure wave and volume flow rate at the pulse tube hot end. Experiments are then carried out to investigate the performance. The pressure ratio at the compression space is maintained at 1.37, for the double inlet type, the system obtains 1.1 W cooling power at 20 K with 390 W acoustic power input and the relative Carnot efficiency is only 3.85%; while for the stepped warm displacer type, the system obtains 1.06 W cooling power at 20 K with only 224 W acoustic power input and the relative Carnot efficiency can reach 6.5%. 相似文献
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《低温学》2018
Temperature is an extremely important parameter for space-borne infrared detectors. To develop a quantum-well infrared photodetector (QWIP), a high-efficiency Stirling-type pulse tube cryocooler (PTC) has been designed, manufactured and experimentally investigated for providing a large cooling power at 40 K cold temperature. Simulated and experimental studies were carried out to analyse the effects of low temperature on different energy flows and losses, and the performance of the PTC was improved by optimizing components and parameters such as regenerator and operating frequency. A no-load lowest temperature of 26.2 K could be reached at a frequency of 51 Hz, and the PTC could efficiently offer cooling power of 3 W at 40 K cold temperature when the input power was 225 W. The efficiency relative to the Carnot efficiency was approximately 8.4%. 相似文献
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This research paper focuses on the experimental investigation of the Stirling-type pulse tube refrigerator with cold compression concept. Due to this innovative feature, the pulse tube refrigerator can reach lower temperature effectively other typical single-stage Stirling-type pulse tube refrigerators. The experiment as a proof of concept is carried out to demonstrate the capability of the pulse tube refrigerator operating between 80 K and 20 K. The cold linear compressor, which is submerged in a liquid nitrogen bath, produces cold mass flow with the efficiency of 85% for all the frequencies. At the lowest temperature part of the pulse tube refrigerator, the no-load temperature of 18.7 K is recorded and the cooling power of 0.4 W is measured at 20 K. The experimental results are analyzed in dynamic and thermal aspects by using the numerical model. The model can well explain how much losses are distributed in the system. 相似文献