Cryogenics最新文献_第3页

Constructing 3D boron nitride nanoribbons and nanosheets networks for enhanced cryogenic thermal management in epoxy composites 构建三维氮化硼纳米带和纳米片网络以增强环氧复合材料的低温热管理

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2026-03-01 Epub Date: 2026-01-16 DOI: 10.1016/j.cryogenics.2026.104289

Yue Xiang , Zhicong Miao , Zhixiong Wu , Tao Wang , Yuqiang Zhao , Yemao Han , Chuanjun Huang , Rongjin Huang , Laifeng Li

To address the quenching issues caused by the low thermal conductivity of epoxy resin (EP) in superconducting applications, this study enhances the comprehensive performance of epoxy-based composites by constructing a three-dimensional boron nitride thermal network. A self-supporting framework integrating boron nitride nanoribbons (BNNR) and boron nitride nanosheets (BNNS) was developed and incorporated into the epoxy matrix. The influence of filler content on the thermal conductivity, electrical insulation, and thermal expansion behavior of the composite was systematically investigated. The results demonstrate that the fabricated composites exhibit excellent thermal performance across the temperature range from 70 K to room temperature. With an 18.96 wt% incorporation of the three-dimensional thermal network, the composite achieves a thermal conductivity of 0.63 W/(m·K) at 70 K, representing a 575% enhancement compared to pure epoxy resin. Simultaneously, the material maintains outstanding electrical insulation characteristics, with volume resistivity consistently exceeding 10¹⁴ Ω·cm. Moreover, the composites’ linear coefficient of thermal expansion (CTE) decreases significantly with increasing filler content, effectively mitigating thermal stress in superconducting devices. This study provides novel insights and experimental foundations for developing high-thermal-conductivity epoxy-based insulating materials suitable for superconducting applications.

为了解决环氧树脂（EP）在超导应用中导热系数低导致的淬火问题，本研究通过构建三维氮化硼热网络来提高环氧基复合材料的综合性能。制备了氮化硼纳米带（BNNR）和氮化硼纳米片（BNNS）的自支撑骨架，并将其整合到环氧基体中。系统研究了填料含量对复合材料导热性、电绝缘性和热膨胀性能的影响。结果表明，制备的复合材料在70 K至室温范围内均表现出优异的热性能。三维热网络的比重为18.96 wt%，复合材料在70 K时的导热系数为0.63 W/(m·K)，与纯环氧树脂相比提高了575%。同时，材料保持了优异的电绝缘特性，其体积电阻率始终超过1014 Ω·cm。此外，随着填料含量的增加，复合材料的线性热膨胀系数（CTE）显著降低，有效地缓解了超导器件中的热应力。该研究为开发适合超导应用的高导热环氧基绝缘材料提供了新的见解和实验基础。

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引用次数: 0

Influencing mechanism of the non-isothermal behavior of an isolated vapor bubble in liquid oxygen 液氧中孤立汽泡非等温行为的影响机理

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2026-03-01 Epub Date: 2026-01-19 DOI: 10.1016/j.cryogenics.2026.104292

Mingkun Xiao, Yonghua Huang, Guang Yang, Chunyu Li, Aifeng Cai, Jingyi Wu

The investigation of the evolution of the cryogenic gas–liquid interface is crucial for the storage and management of cryogenic propellants in on-orbit tanks. Studying the non-isothermal growth of isolated bubbles under normal gravity provides a foundation for understanding the distribution of the cryogenic gas–liquid interface. However, a low boiling point, low surface tension coefficient, and low viscosity lead to bubble behaviors that differ from those of room-temperature liquids, increasing the difficulties in investigating cryogenic behaviors, and the related studies are limited. In this work, a visualization experimental platform for liquid oxygen single bubble pool boiling was established. Liquid oxygen was produced by cooling oxygen with liquid nitrogen, and an optical visualization system was designed to observe bubble behavior. The effects of wall superheat, liquid subcooling, and pressure on bubble growth rate and detachment parameters were investigated. Results indicate that higher wall superheat reduces the waiting time for bubble growth, shortens the bubble growth cycle, and increases the bubble diameter. During the initial growth stage, the bubble diameter follows a

D \sim t^{1 / 2}

trend, transitioning to

D \sim t^{1 / 3}

in the later stage. Bubble growth slows with increasing liquid subcooling, while higher pressure leads to smaller detachment diameters and higher detachment frequencies. The findings compensate for the scarcity of data on the growth of isolated bubbles in cryogenic liquids, and provide important guidance for the development of on-orbit storage and transport technology.

低温气液界面的演化研究对于低温推进剂在轨储罐的储存和管理具有重要意义。研究孤立气泡在重力作用下的非等温生长，为理解低温气液界面的分布提供了基础。然而，低沸点、低表面张力系数和低粘度导致气泡行为与室温液体不同，增加了研究低温行为的难度，相关研究也受到限制。本文建立了液氧单泡池沸腾的可视化实验平台。用液氮冷却氧气产生液氧，并设计了一个光学可视化系统来观察气泡的行为。研究了壁面过热度、液体过冷和压力对气泡生长速率和分离参数的影响。结果表明，较高的壁面过热度缩短了气泡生长的等待时间，缩短了气泡生长周期，增大了气泡直径。在初始生长阶段，气泡直径遵循D ~ t1/2趋势，在后期过渡到D ~ t1/3。随着液体过冷度的增加，气泡的生长速度减慢，而压力越高，分离直径越小，分离频率越高。这一发现弥补了低温液体中孤立气泡生长数据的不足，并为在轨储存和运输技术的发展提供了重要指导。

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引用次数: 0

Permeation through thin polymer films at cryogenic temperatures 低温下通过聚合物薄膜的渗透

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2026-03-01 Epub Date: 2026-01-12 DOI: 10.1016/j.cryogenics.2026.104279

Kjell Westra, Jacob Leachman

Cryogenic propellant bladders could substantially improve propellant storage and slosh characteristics, especially in microgravity conditions. However, an experimental effort in the 1970s showed unacceptably high permeation rates of hydrogen and helium through thin polymer films (candidate materials for bladders) at cryogenic temperatures. A qualitative hypothesis for the increase is the relatively large thermal de Broglie wavelength of hydrogen and helium molecules at cryogenic temperatures could increase the hopping rate of the molecules and resulting bulk permeation. This hypothesis was tested by measuring the leak rate of helium through thin films (on the order of 25 µ m thick) of polyether ether ketone (PEEK), polyetherimide (PEI), ethylene vinyl alcohol (EVOH), and biaxially-oriented polyethylene terephthalate (BoPET) from 190 – 30 K. Hydrogen permeation was also tested through PEEK specimens from 210 – 30 K. A calibrated variable mass-spectrometer and custom sample test-cell and apparatus were utilized. The measurements indicate that permeation follows an Arrhenius relation with decreasing temperature until the limit of the sensor resolution was achieved below ∼90 K for He, and below ∼150 K for H₂. The anomalous increase in permeability with reducing temperature observed in the historical 1970′s study was only reproduced with samples known to have developed leaks in the sealing. Thus, polymer films could be viable permeation barriers for liquid cryogens in aerospace applications, including bladders.

低温推进剂囊体可以大大改善推进剂的储存和晃动特性，特别是在微重力条件下。然而，20世纪70年代的一项实验表明，在低温下，氢和氦通过聚合物薄膜（膀胱的候选材料）的渗透率高得令人无法接受。对这种增加的定性假设是，在低温下，氢和氦分子的热德布罗意波长相对较大，可以增加分子的跳变速率，从而导致体积渗透。通过测量氦在190 - 30 K范围内通过聚醚醚酮（PEEK）、聚醚酰亚胺（PEI）、乙烯醇（EVOH）和双轴取向聚对苯二甲酸乙二醇酯（BoPET）薄膜（厚度约为25 μ m）的泄漏率，验证了这一假设。氢渗透也测试了PEEK样品从210 - 30 K。使用校准的可变质谱仪和定制的样品测试池和设备。测量结果表明，随着温度的降低，渗透遵循Arrhenius关系，直到传感器分辨率的极限达到He低于~ 90 K， H2低于~ 150 K。在20世纪70年代的历史研究中观察到的渗透率随温度降低而异常增加的现象，只有在已知密封中出现泄漏的样品中才能重现。因此，聚合物薄膜可能成为航空航天应用中液冷剂（包括气囊）的可行渗透屏障。

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引用次数: 0

Low-temperature sintering of ex situ processed MgB2 tapes under various hydrogen partial pressures 不同氢分压下非原位加工MgB2带的低温烧结

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2026-02-01 Epub Date: 2025-12-17 DOI: 10.1016/j.cryogenics.2025.104259

Hiroki Fujii

Ex situ processed Fe-sheathed tapes using a mixture of MgB₂ and Sn powders milled for 30 and 100 h were sintered at 410 – 710 ℃ under hydrogen partial pressures of 0, 5, 20, 50 and 100 kPa in a gas mixture of Ar and H₂. The filling powders were pure MgB₂ and the mixture with the addition of 3.7 wt% Sn. Without addition of Sn, tapes sintered under a pure H₂ atmosphere show well-connected structure of grains in the core or improved grain connectivity in microstructure compared to tapes sintered under a pure Ar atmosphere. The undoped tapes sintered at 680 ℃ under pure Ar or 530 ℃ under pure H₂ exhibit transport critical current density (J_c) values of approximately 150 A/mm² at 4.2 K and 10 T. Therefore, sintering under pure H₂ is effective in reducing the sintering temperature. The sintering temperature of 530 ℃ is lower than the melting point of lightweight Al, which is one of the candidates for sheath materials for MgB₂ conductors, which is 660 ℃. Regarding the control of hydrogen partial pressure, the critical temperature (T_c) of the tapes increases by up to 2 K as the hydrogen partial pressure increases. However, the transport J_c values at 4.2 K and 10 T of these tapes sintered in a flow of mixed gas of Ar and H₂ do not improve compared to those sintered under pure H₂. Thus, sintering under pure H₂ is the most effective in the improvement in T_c and transport J_c. Whereas Sn addition is effective in shifting the transport J_c versus sintering temperature curves to a lower sintering temperature under pure Ar, the addition brings about neither such a shift nor transport J_c enhancement under pure H₂. These results lead to the fabrication of lightweight Al-sheathed conductors for applications such as maglev trains.

采用MgB2和Sn混合粉末，在Ar和H2混合气体中，在410 ~ 710℃下，在0、5、20、50和100 kPa的氢分压条件下，进行非原位加工铁包覆带的烧结。填充粉末为纯MgB2和添加3.7 wt% Sn的混合物。与纯Ar气氛下烧结的带相比，未添加Sn的纯H2气氛下烧结的带芯晶粒连接良好，微观结构上晶粒连通性提高。在纯Ar和纯H2下分别在680℃和530℃下烧结的未掺杂带在4.2 K和10 t下的输运临界电流密度（Jc）约为150 A/mm2，因此，纯H2下烧结能有效降低烧结温度。烧结温度为530℃，低于轻质铝的熔点660℃，是MgB2导体护套材料的候选材料之一。在氢气分压的控制方面，随着氢气分压的增加，胶带的临界温度（Tc）提高了2 K。然而，在Ar和H2混合气体中烧结的带在4.2 K和10 T时的输运Jc值与纯H2下烧结的带相比没有提高。因此，纯H2烧结对提高Tc和输运Jc最为有效。在纯Ar条件下，Sn的加入可以有效地将输运Jc随烧结温度曲线移动到较低的烧结温度，而在纯H2条件下，Sn的加入既没有引起这种移动，也没有增强输运Jc。这些结果导致了用于磁浮列车等应用的轻质铝护套导体的制造。

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引用次数: 0

β’-Gd2(MoO4)3: A promising candidate in the sub-Kelvin temperature region β′-Gd2(MoO4)3：亚开尔文温度区域的一个有希望的候选者

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2026-02-01 Epub Date: 2025-12-19 DOI: 10.1016/j.cryogenics.2025.104269

Zuhua Chen , Jiahao Gao , Xinqi Zheng , Guochun Zhang , Lei Xi , Zhenxing Li , Shilin Yu , Heng Tu , Jun Shen , Shouguo Wang

Magnetic refrigeration technology is one of the important technologies to realize sub-Kelvin temperature environment, in which magnetocaloric materials are of great importance. Polycrystalline powder of β’-Gd₂(MoO₄)₃ was prepared by solid-phase synthesis, and the structure as well as magnetic properties were further investigated. The thermomagnetic curves show that the magnetic ordering temperature is about 0.6 K for β’-Gd₂(MoO₄)₃. The maximum magnetic entropy change of β’-Gd₂(MoO₄)₃ was calculated to be 20.7 and 34.1J kg⁻¹·K⁻¹ under the magnetic field changes from 0 to 1 T and 2 T, respectively. Moreover, the magnetic entropy change curves of β’-Gd₂(MoO₄)₃ at low field have obvious platform-like characteristic, which allows it to act as a refrigerant for wide refrigeration temperature range, thereby improving the overall heat transfer efficiency of the system. These properties make β’-Gd₂(MoO₄)₃ a powerful candidate of magnetic refrigeration materials in the sub-Kelvin temperature cooling.

磁致冷技术是实现亚开尔文温度环境的重要技术之一，其中磁致热材料具有重要意义。采用固相法制备了β′-Gd2(MoO4)3多晶粉体，并对其结构和磁性能进行了进一步研究。热磁曲线表明，β′-Gd2(MoO4)3的磁有序温度约为0.6 K。计算得到β′-Gd2(MoO4)3在0 ~ 1 T和2 T磁场变化下的最大磁熵变化分别为20.7和34.1J kg−1·K−1。此外，β′-Gd2(MoO4)3在低场下的磁熵变化曲线具有明显的平台型特征，可以在较宽的制冷温度范围内作为制冷剂，从而提高了系统的整体换热效率。这些特性使β′-Gd2(MoO4)3成为亚开尔文温度冷却磁致冷材料的有力候选材料。

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引用次数: 0

Design and characterization of an alumina coated helium gas gap heat switch with adjustable gap width 间隙宽度可调的氧化铝包覆氦气间隙热开关的设计与表征

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2026-02-01 Epub Date: 2025-12-25 DOI: 10.1016/j.cryogenics.2025.104275

Kun Wang , Shuai Ma , Kuifan Zha , Liming Han , Yi Liao , Changzhao Pan

Gas gap heat switches, with the advantages of simple operation, no moving parts, and large switching ratios, are widely applied in helium evaporation refrigerator, adiabatic demagnetization refrigerator, and dilution refrigerator. In this study, a sintered alumina (Al₂O₃) coated helium gas gap heat switch (GGHS) was successfully developed, adopting a concentric copper block structure, where the gap width was precisely controlled by adjusting the thickness of the sintered alumina coating. In the constructed 4 K test system, the thermal conductance, switching temperature, and switching time of the switch were systematically tested, and the results show that when the average temperature of the switch is 30 K, the peak thermal conductance reaches 255 mW/K; at a cold end temperature of 3 K, the OFF and ON state thermal conductance are 0.27 mW/K and 35 mW/K, respectively. Further verification of the switching temperature shows that the theoretical prediction agrees well with the experimental data, confirming the reliability of the theoretical model. In addition, the switch exhibits good dynamic response characteristics, with a switching time of 70 s from OFF state to ON state, and only 17 min required for the adsorption pump to cool during the ON to OFF transition. Finally, to evaluate its practical performance, the heat switch was implemented in a custom-built dilution refrigerator, where the system successfully cooled to 10 mK within 32.5 h. The above study confirms that the sintered alumina coating helium gas gap heat switch provides reliable performance, offering an effective solution for thermal management in cryogenic systems.

气隙热开关具有操作简单、无运动部件、开关比大等优点，广泛应用于氦气蒸发制冷机、绝热退磁制冷机、稀释制冷机等。本研究成功研制了一种烧结氧化铝（Al2O3）涂层氦气间隙热开关（GGHS），采用同心铜块结构，通过调整烧结氧化铝涂层的厚度来精确控制间隙宽度。在搭建的4 K测试系统中，对开关的热导率、开关温度、开关时间进行了系统测试，结果表明：当开关的平均温度为30 K时，热导率峰值达到255 mW/K；冷端温度为3 K时，关闭和打开状态的热导率分别为0.27 mW/K和35 mW/K。对开关温度的进一步验证表明，理论预测与实验数据吻合较好，证实了理论模型的可靠性。此外，该开关具有良好的动态响应特性，从OFF状态切换到ON状态的切换时间为70 s，从ON到OFF过渡过程中吸附泵的冷却时间仅为17 min。最后，为了评估其实际性能，将热开关应用于定制的稀释冰箱中，系统在32.5 h内成功冷却到10 mK。上述研究证实了烧结氧化铝涂层氦气间隙热开关具有可靠的性能，为低温系统的热管理提供了有效的解决方案。

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引用次数: 0

Magnetic properties and low-temperature magnetocaloric performances in fluorite-type Tb2Zr2O7 compound 萤石型Tb2Zr2O7化合物的磁性能和低温磁热性能

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2026-02-01 Epub Date: 2025-12-16 DOI: 10.1016/j.cryogenics.2025.104266

Jiameng Xu, Fuyu Yang, Yikun Zhang, Xinyu Zhao, Zhe Kong

The low-temperature magnetocaloric (MC) performances in rare-earth (RE)-based magnetic materials have been determined intensively which are aimed to explore suitable materials for magnetic refrigeration (MR) application. In this work, we synthesized the Tb₂Zr₂O₇ compound using solid-state reaction method and characterized its crystal structure, elemental valence states, magnetism, and low-temperature MC properties. The Tb₂Zr₂O₇ compound crystallizes in a fluorite-type cubic structure and orders magnetically around the temperature of 2.2 K. The consistent elements are all distributed uniformly and presented as Tb³⁺, Zr⁴⁺, and O^2– valence states, respectively. Prominent low-temperature MC performances have been realized in Tb₂Zr₂O₇ compound which were related to its second order type magnetic phase transition. The MC parameters of maximum magnetic entropy change and refrigerant capacity for Tb₂Zr₂O₇ compound under magnetic field variation of 0–7 T reach 11.8 J/kg·K and 192.2 J/kg, respectively. These MC parameters are comparable with some recently reported RE-based high-performing MC materials, making the Tb₂Zr₂O₇ compound may also considerable for low-temperature MR applications.

对稀土基磁性材料的低温磁热性能进行了深入的研究，旨在探索适合磁制冷应用的材料。本文采用固相反应方法合成了Tb2Zr2O7化合物，并对其晶体结构、元素价态、磁性和低温MC性能进行了表征。Tb2Zr2O7化合物结晶为萤石型立方结构，在2.2 K左右有磁性有序。一致元素分布均匀，分别表现为Tb3+、Zr4+和O2 -价态。Tb2Zr2O7化合物具有优异的低温MC性能，这与其二级磁相变有关。在0 ~ 7 T的磁场变化下，Tb2Zr2O7化合物的最大磁熵变化和制冷剂容量MC参数分别达到11.8 J/kg·K和192.2 J/kg。这些MC参数与最近报道的一些基于re的高性能MC材料相当，使得Tb2Zr2O7化合物也可以用于低温MR应用。

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引用次数: 0

Measurement of the thermal conductivity of high-purity aluminum and OFHC copper for the CUPID pulse tube cryocoolers thermal links 用于丘比特脉冲管制冷机热链路的高纯度铝和OFHC铜导热系数的测量

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2026-02-01 Epub Date: 2025-12-29 DOI: 10.1016/j.cryogenics.2025.104276

F. Agresti , A. Benato , C. Bucci , I. Calliari , A. D’Addabbo , S. D’Eramo , S. Di Lorenzo , S. Fu , P. Gorla , L. Marini , M. Olmi , L. Pezzato , M. Pigato , A. Puiu , S. Quitadamo , A. Zambon

We present a campaign of thermal conductivity measurements of Oxygen Free High Conductivity (OFHC) copper (

>

99.9% purity) and high-purity 5N and 6N aluminum. High-purity aluminum is devoted to replace the current OFHC copper thermal links of the Pulse Tube Cryocoolers (PTC) installed in the

^{3} He

-

^{4} He

dilution cryostat of the CUORE (Cryogenic Underground Observatory for Rare Events) experiment, in view of the future commissioning of the CUPID (CUORE Upgrade with Particle IDentification) experiment, both dedicated to the search of neutrinoless double beta decay. We perform thermal conductivity measurements on high-purity aluminum (

Al

-5N and

Al

-6N) and OFHC copper samples across the temperature range from 12 K to 45 K, and then extrapolate them down to 3.5 K, namely the minimum temperature achieved by the second stage of the CUORE PTC. We estimated that the thermal conductivity of high-purity aluminum at 3.5 K is up to

≃

17 times higher than that of OFHC copper. However, the measured thermal conductivity of high-purity aluminum has been found to be limited by the boundary thermal resistance ascribed to the oxidation of the aluminum surface. By quantifying and accounting for such contribution, we estimated the actual thermal conductivity of

Al

-6N to be

≃

61 times higher value than that of OFHC copper. These findings suggest that high-purity aluminum thermal links offer a promising solution to meet the stringent requirements of the successor of CUORE, the CUPID experiment, in terms of cooling power enhancement and vibration suppression.

我们提出了一项无氧高导电性（OFHC）铜（纯度>；99.9%）和高纯5N和6N铝的热导率测量运动。高纯铝专门用于取代目前安装在CUORE（低温地下罕见事件观测站）实验3He-4He稀释低温恒温器（PTC）中的脉冲管制冷机（PTC）的OFHC铜热链接，以考虑到丘比特（CUORE升级与粒子识别）实验的未来调试，这两个实验都致力于寻找中微子双β衰变。我们在12 K至45 K的温度范围内对高纯度铝（Al-5N和Al-6N）和OFHC铜样品进行导热系数测量，然后将其外推至3.5 K，即CUORE PTC第二阶段达到的最低温度。我们估计在3.5 K时，高纯度铝的导热系数比OFHC铜的导热系数高17倍。然而，高纯度铝的热导率被发现受到铝表面氧化引起的边界热阻的限制。通过量化和计算这一贡献，我们估计Al-6N的实际导热系数比OFHC铜高61倍。这些发现表明，高纯度铝热链接提供了一个有希望的解决方案，以满足CUORE的继任者丘比特实验在冷却功率增强和振动抑制方面的严格要求。

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引用次数: 0

A gravity independent hydrogen heat pipe 一种不依赖重力的氢热管

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2026-02-01 Epub Date: 2025-12-23 DOI: 10.1016/j.cryogenics.2025.104270

Ziyang Hang, John Pfotenhauer, Franklin Miller

A new type of heat pipe called Hybrid Conventional Pulsating Heat Pipe (HCPHP), which works similarly to a conventional heat pipe but retains the advantageous geometry of a pulsating heat pipe, is experimentally verified within the saturated hydrogen temperature range and under horizontal working orientation. The Hydrogen HCPHP shows up to 1.625 W of heat transfer with thermal conductance up to 6.15 W/K and effective thermal conductivity up to 54,621 W/m-K over a 250 mm heat transfer distance. Experimental investigations of the hydrogen HCPHP focus on the condenser temperature, fluid fill ratio, and applied heat load. Thermohydraulic behavior of the Hydrogen HCPHP is analyzed, providing insights into its performance and behavior.

混合常规脉动热管（HCPHP）是一种新型热管，它的工作原理与传统热管相似，但保留了脉动热管的优势几何形状，在饱和氢温度范围内和水平工作方向下进行了实验验证。在250mm的传热距离上，HCPHP的换热量为1.625 W，导热系数为6.15 W/K，有效导热系数为54,621 W/m-K。实验研究主要集中在凝汽器温度、充液比和外加热负荷方面。分析了氢气HCPHP的热液行为，为其性能和行为提供了见解。

引用次数: 0

Investigation of the effect of electrode configuration on sensitivity and linearity of capacitance-based void fraction sensors for cryogenic nitrogen two-phase flow 电极结构对电容式低温氮两相流空分数传感器灵敏度和线性度影响的研究

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2026-02-01 Epub Date: 2025-12-20 DOI: 10.1016/j.cryogenics.2025.104268

Tony John , Rijo Jacob Thomas , K.A. Shafi

Capacitance-based sensors, which are favored for the measurement of void fraction in two-phase cryogenic flow, suffer from low sensitivity and linearity due to the low relative permittivity of cryogens and the non-uniform electric field inside the flow area, respectively. This paper compares the sensitivity and linearity of concave, parallel plate and concentric electrodes for use in capacitance-based void fraction sensors. The simulation model was validated using a concave electrode sensor with stratified flow. The simulation results show that of the three electrode shapes considered, concentric electrodes exhibit excellent sensitivity for both stratified and annular flow regimes and good linearity for stratified flow. Even though they have low sensitivity, the parallel plate electrodes give the best linear behavior between void fraction and capacitance for both flow regimes.

由于低温介质的相对介电常数较低，流动区域内电场不均匀，电容式传感器的灵敏度较低，线性度较低，是两相低温流动中空隙率测量的理想传感器。本文比较了凹电极、平行电极和同心电极在电容式空隙率传感器中的灵敏度和线性度。采用分层流凹电极传感器对仿真模型进行了验证。仿真结果表明，在考虑的三种电极形状中，同心电极对分层流和环形流都具有良好的灵敏度，对分层流具有良好的线性性。尽管它们的灵敏度较低，但平行板电极在两种流动模式下的空隙率和电容之间具有最佳的线性行为。

引用次数: 0