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为了既能降到液氢温区又能确保制冷机的温度稳定性,开展了仅采用长颈管,不使用双向进气进行调相的单级高频多路旁通型脉冲管制冷机的实验研究。首先用数值计算的方法获得了多路旁通开度是否最佳的判据。研制出的制冷机在充气压力1.73MPa,输入电功220W时,无负荷最低制冷温度能够降到23.6K,为目前所报道的在没有双向进气时单级高频脉冲管制冷机获得的最低温度。在达到稳定状态后,制冷机性能稳定,温度波动幅值小于0.1K。在220W输入电功下,能够在29.2K获得0.516W,34.3K获得1.0W的制冷量。 相似文献
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《深冷技术》1999,(3)
<正>993101 分离型两级脉冲管制冷机的实验研究杨鲁伟等 《低温与超导》 1999 No1 1~5脉冲管制冷机的实用化是目前脉冲管制冷机的一个主要研究方向。文章介绍了作者为提高脉冲管效率而研究的一种分离结构的两级脉冲管制冷机。实验获得了11 7K的最低温度,制冷量3W/20K。采用名义功率2.2kWG—M压缩机驱动得到了12.4K的最低温度,制冷量2W/18.5K,4W/24.6K,实际输入功率约1.5kW。这一结果已基本达到了实用化应用的要求。该研究表明脉冲管制冷机的效率在20K温区已接近类似的G—M制冷机。993102 使用孔板式换热器的脉冲管制冷 相似文献
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研制了一台低于40 K温区的单级同轴型高频脉冲管制冷机,采用多路旁通结构,在输入功率为222 W时,其最低温度达到34.22 K,并比较了惯性管、惯性管加双向进气、惯性管加多路旁通以及惯性管加双向进气加多路旁通4种固定调相装置的差异(其中双向进气采用喷嘴结构).实验结果表明:惯性管、喷嘴、多路旁通组合方式是一种非常有效的降低制冷温度的方式,是应用深低温区单级脉冲管制冷机调相方式的最佳选择;而惯性管则是应用于较高温区大冷量的最佳的调相方式.实验还表明,多路旁通加喷嘴结构能够降低脉冲管内部的直流,有效地提高脉冲管制冷机的性能. 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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《低温学》2018
This paper presents the CFD modeling and experimental verifications of oscillating flow and heat transfer processes in the micro coaxial Stirling-type pulse tube cryocooler (MCSPTC) operating at 90–170 Hz. It uses neither double-inlet nor multi-bypass while the inertance tube with a gas reservoir becomes the only phase-shifter. The effects of the frequency on flow and heat transfer processes in the pulse tube are investigated, which indicates that a low enough frequency would lead to a strong mixing between warm and cold fluids, thereby significantly deteriorating the cooling performance, whereas a high enough frequency would produce the downward sloping streams flowing from the warm end to the axis and almost puncturing the gas displacer from the warm end, thereby creating larger temperature gradients in radial directions and thus undermining the cooling performance. The influence of the pulse tube length on the temperature and velocity when the frequencies are much higher than the optimal one are also discussed. A MCSPTC with an overall mass of 1.1 kg is worked out and tested. With an input electric power of 59 W and operating at 144 Hz, it achieves a no-load temperature of 61.4 K and a cooling capacity of 1.0 W at 77 K. The changing tendencies of tested results are in good agreement with the simulations. The above studies will help to thoroughly understand the underlying mechanism of the inertance MCSPTC operating at very high frequencies. 相似文献
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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。 相似文献
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High frequency (30-50 Hz) multi-stage pulse tube coolers that are capable of reaching temperatures close to 20 K or even lower are a subject of recent research and development activities. This paper reports on the design and test of a two-stage pulse tube cooler which is driven by a linear compressor with nominal input power of 200 W at an operating frequency of 30-45 Hz. A parallel configuration of the two pulse tubes is used with the warm ends of the pulse tubes located at ambient temperature. For both stages, the regenerator matrix consists of a stack of stainless steel screen. At an operating frequency of 35 Hz and with the first stage at 73 K a lowest stationary temperature of 19.6 K has been achieved at the second stage. The effects of input power, frequency, average pressure, and cold head orientation on the cooling performance are also reported. An even lower no-load temperature can be expected from the use of lead or other regenerator materials of high heat capacity in the second stage. 相似文献
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A high pressure hybrid refrigerator that combines the active magnetic refrigeration effect with the Stirling cycle refrigeration effect at room temperature is studied here. In the apparatus, a helium-gas-filled alfa-type Stirling refrigerator uses Gd sheets as the regenerator and the regenerator is put in a magnetic field varying from 0 to 1.4 T, which is provided by a Halbach-type rotary permanent magnet assembly. With an operating pressure of 5.5 MPa and a frequency of 2.5 Hz, a no-load temperature of 273.8 K was reached in 9 minutes, which is lower than that of 277.6 K for pure Stirling cycle. For the hybrid operation, cooling powers of 40.3 W and 56.4 W were achieved over temperature spans of 15 K and 12 K, respectively. For the latter case, the cooling power improves by 28.5% if compared with that exploiting only the Stirling cycle refrigeration effect. 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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With the combined advantages of high reliability, compact size and low electromagnetic interference, a high frequency operating thermoacoustic cooler system, i.e. a pulse tube cooler driven by a thermoacoustic heat engine, is quite promising for space applications. This article introduced a high frequency standing-wave thermoacoustic heat engine-driven pulse tube cooler system working around 300 Hz with axial length being 1.2 m. To improve the thermal efficiency of such system, an optimization has been carried out, both analytically and experimentally, by observing the influence of the dimensions of the stack, the hot buffer length and the acoustic pressure amplifier tube length. So far, a no-load temperature of 68.3 K has been obtained with 4.0 MPa helium and 750 W heating power. With 500 W heating power, a no-load temperature of 76.9 K and 0.2 W cooling power at 80 K have been achieved. Compared with former reports, the performance has been improved. 相似文献
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A two-stage Stirling-type U-shape pulse tube cryocooler driven by a 10 kW-class linear compressor was designed, built and tested. A special feature of the cold head is the absence of a heat exchanger at the cold end of the first-stage, since the intended application requires no cooling power at this intermediate temperature. Simulations where done using Sage-software to find optimum operating conditions and cold head geometry. Flow-impedance matching was required to connect the compressor designed for 60 Hz operation to the 40 Hz cold head. A cooling power of 12.9 W at 25 K with an electrical input power of 4.6 kW has been achieved up to now. The lowest temperature reached is 13.7 K. 相似文献
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High capacity pulse tube refrigerator (HCPTR) is a new generation of cryocoolers tailored to provide more than 250 W of cooling power at cryogenic temperatures. The most important characteristics of HCPTR when compared to other types of pulse tube refrigerators are a powerful pressure wave generator, and an accurate design. In this paper the influence of geometrical and operating parameters on the performance of a double inlet pulse tube refrigerator (DIPTR) is studied. The model is validated with the existing experimental data. As a result of this optimization, a new configuration of HCPTR is proposed. This configuration provides 335 W at 80 K cold end temperature with a frequency of 50 Hz and COP of 0.05. 相似文献
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L.M. Qiu Q. Cao X.Q. Zhi L. Han Z.H. Gan Y.B. Yu Y. Liu X.J. Zhang J.M. Pfotenhauer 《低温学》2012,52(7-9):382-388
A Stirling pulse tube cryocooler (SPTC) operating at the liquid-helium temperatures represents an excellent prospect for satisfying the requirements of space applications because of its compactness, high efficiency and reliability. However, the working mechanism of a 4 K SPTC is more complicated than that of the Gifford McMahon (GM) PTC that operates at the relatively low frequency of 1–2 Hz, and has not yet been well understood. In this study, the primary operating parameters, including frequency, charge pressure, input power and precooling temperature, are systematically investigated in a home-developed separate three-stage SPTC. The investigation demonstrates that the frequency and precooling temperature are closely coupled via phase shift. In order to improve the cooling capacity it is important to lower the frequency and the precooling temperature simultaneously. In contrast to the behavior predicted by previous studies, the pressure dependence of the gas properties results in an optimized pressure that decreases significantly as the temperature is lowered. The third stage reaches a lowest temperature of 4.97 K at 29.9 Hz and 0.91 MPa. A cooling power of 25 mW is measured at 6.0 K. The precooling temperature is 23.7 K and the input power is 100 W. 相似文献