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研制1台新型液氦温区分离型二级脉管制冷机,该制冷机由2台独立的脉管制冷机组成,一级回热器冷端和二级回热器中部通过热桥相连,从根本上弥补了传统直接耦合型多级脉管制冷机级间干扰的不足.采用双压缩机双旋转阀驱动该二级脉管制冷机,第二级最低温度达到了2.5 K,在4.2 K下有508 mW制冷量,同时一级在37.5 K有15 W制冷量.第二级充气压力由1.7 MPa增大到1.85 MPa,制冷机在4.2 K下的制冷量可以达到590 mW.为了能简化结构、扩大应用,提出采用单压缩机单旋转阀驱动该分离型脉管制冷机,达到了相同的制冷性能. 相似文献
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小型回热式低温制冷机中的冷端换热器在制冷量高效传输过程中起着至关重要的作用,而这一作用往往被忽视.研究发现,通过脉管冷端换热器的结构改进,液氦温区脉管制冷机在4.2 K温区的制冷量可以得到显著提高.实验结果表明,在压缩机输入功率分别为4.8 kW和6.0 kW的条件下,双向进气型二级脉管制冷机在4.2 K获得了760 mW和900 mW的制冷量,相应的制冷系数(COP)为1.58×10-4和1.50×10-4.该脉管制冷机在4.2 K获得的最大制冷量达960 mW. 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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液氦温区脉管制冷机的优化实验 总被引:2,自引:2,他引:0
研制了一台用作德国国家标准局 (PTB)约瑟夫森效应 (JosephsonEf fect) 1V电压标准冷却系统的二级脉管制冷机。其设计要求在 4 2K提供 1 0 0mW左右制冷量 ,并同时冷却 70K左右的冷屏。采用额定功率为 1 8kW的氦压缩机驱动脉管制冷机 ,在不同制冷量负荷条件下分别对其进行了优化。初步实验结果表明 ,在输入功率 1 8kW的情况下 ,该制冷机最低制冷温度达 2 8K ,4 2K制冷量最大达 1 90mW ,制冷系数达 1 0 6× 1 0 4,火用效率最高达 1 1 3% ,可以充分满足冷却电压标准芯片的需要。此外 ,还与用 6kW压缩机驱动同一制冷机的实验结果进行了比较。 相似文献
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在一台具有独立气体回路的液氦温区G-M型二级脉管制冷机上,采用3He为第二级制冷工质,获得了1.27 K的最低无负荷制冷温度.研究表明,以3He为第二级工质,该系统在2 K,3 K和4.2 K,分别可以提供42 mW,205.5 mW和518.3 mW的制冷量,第一级和第二级压缩机相应的输入功率分别为4.3 kW(Leybold CP4000氦压缩机)和1.3 kW(Leybold RW2氦压缩机).与两级均采用4He工质的情况相比,在相同的条件下(相同的压缩机耗功:4.3 kW 1.3 kW),第二级采用3He为工质,使得该二级脉管制冷机在4.2 K的制冷量提高了40.5%. 相似文献
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分离型二级脉管制冷机的实验研究第一部分20~40 K温区单级大功率脉管制冷机 总被引:3,自引:3,他引:0
为了满足液氦温区分离型二级脉管制冷机第二级预冷的需要,设计制作了1台20~40K温区单级大功率脉管制冷机.采用额定功率为6 kW的压缩机驱动该制冷机,最低制冷温度达13.8K,刷新了单级脉管制冷机最低制冷温度纪录.该制冷机在40 K可获得高达55.9 W的制冷量,基本可以满足15~40 K温区超导磁体等冷却的需要.着重分析了频率、充气压力和不同压缩机对系统制冷性能的影响,测试了长时间运行中系统性能的变化情况. 相似文献
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分析了在自行研制的双小孔型二级脉管制冷机实验过程中回热器对脉管制冷机性能的影响,给出了合理的回热器布置方式,讨论了回热器形变及压缩机油污染对脉管制冷机性能的影响,指出了羊毛毡在隔离磁性材料Nr3Ni粉尘中所起的重要作用。在优化改进的基础上,该机达到了3.1K的最低无负荷温度。 相似文献
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具有独立气路的液氦温区G-M型二级脉管制冷机性能研究 总被引:1,自引:1,他引:1
研究了一台具有独立气体回路的液氦温区G-M型二级脉管制冷机的制冷性能.目前的实验装置由两套独立的单级双向进气型脉管系统构成,第一级冷头对第二级进气的预冷通过安装在第二级回热器中部的换热器与一级冷头之间的热联接来实现.研究表明,该制冷机采用4He为工质,分别以Leybold CP4000和RW2氦压缩机来驱动第一级和第二级,可以获得2.18 K的最低无负荷制冷温度,4.2 K提供的最大制冷量为595 mW. 相似文献
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热耦合二级Stirling型脉管制冷机的性能研究 总被引:3,自引:2,他引:1
建立热耦合二级Stirling型脉管制冷机实验装置.通过实验,系统研究了交变流动工质的工作频率和平均工作压力对热耦合二级Stirling型脉管制冷机性能的影响,详细报道并分析讨论了实验结果.以氦气作为工质,在优化工作频率和平均工作压力条件下,热耦合二级Stirling型脉管制冷机获得了13.52 K的无负荷制冷温度. 相似文献
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Regenerative cryocoolers that employ 4He as working fluid can only reach a lowest temperature of about 2 K. This limitation can be overcome by the use of 3He as working fluid. Here we report on the performance of a two-stage pulse tube cooler that consists of two parallel stages with independent gas circuits. The pressure oscillation in each stage is generated by means of a separate compressor in combination with a rotary valve. With 4He in both stages, the minimum no-load temperature of the 2nd stage was 2.23 K, and cooling powers of 50 W at 53 K and 380 mW at 4.2 K were simultaneously available at electrical input powers of 4.54 and 1.45 kW to the 1st and 2nd stage, respectively. Using 3He as working fluid in the 2nd stage, a minimum stationary temperature of 1.27 K has been achieved, which is, up to now, the lowest temperature obtained by regenerative cryocoolers. At an electrical input power of 1.3 kW, the 2nd stage provides a cooling power of 42 mW at 2.0 K and 518 mW at 4.2 K. With 3He, at the same operating condition, the cooling power at 4.2 K was found to be larger than with 4He. 相似文献
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This article introduces our recent experimental advances on a 300 Hz pulse tube cooler driven by a thermoacoustic standing-wave engine. After some modifications on the engine, the integral system performance is improved, which leads to a better cooling performance of the high frequency pulse tube cooler compared with that in former reports. Cooling powers of the pulse tube cooler with different operating conditions have been measured in detail for the first time. So far, a lowest no-load temperature of 68 K and a maximum cooling power of 1.16 W at 80 K have been obtained with the mean pressure and the heating power being 4.1 MPa and 1 kW, respectively. 相似文献
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A set of Stirling-type non-magnetic and non-metallic co-axial pulse tube cryocoolers, intended to achieve portable cryogen-free systems with very low interference for high-Tc SQUIDs operation, have been designed and tested in TIPC/CAS. The key feature is that all cooler components in the vicinity of SQUIDs pick-up loops are made of non-magnetic and non-metallic materials, in order to eliminate complicated interference and realize direct couple with SQUIDs. The cooling options, cooler interference and corresponding solutions are reviewed briefly, and then we focus our attention on the cryogenic design and selection of the materials. Over 30 cooler samples have been fabricated and tested systematically. A typical cooling power of over 100 mW at 80 K with 70 W input electrical power has been achieved. Detailed cooling performance and elementary interference characteristics of the coolers are also analyzed and evaluated. 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