Cryogenics最新文献_第6页

Energy loss analysis of cryogenic neon turboexpander based on entropy production theory 基于熵产理论的低温氖涡轮膨胀机能量损失分析

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-10-22 DOI: 10.1016/j.cryogenics.2025.104217

Zhihang Zhang , Zhengze Chang , Changcheng Ma , Yi Huo , Rui Ge

The cryogenic neon turboexpander (CNTE) serves as the core component of the neon Claude cycle refrigerator. A comprehensive understanding of its internal flow loss mechanisms is critical for further enhancing CNTE performance. This study employs computational fluid dynamics (CFD) simulations coupled with entropy production analysis to investigate the flow behavior and energy dissipation mechanisms within the CNTE. The numerical results demonstrate that approximately 91.5 % of the total entropy production originates from the impeller and diffuser components, and the primary loss mechanism stems from turbulent energy dissipation occurring at the interface of tip clearance leakage flow and the mainstream. Quantitative analysis reveals that expanding the tip clearance from 0 mm to 0.6 mm results in an 11.13 % deterioration in isentropic efficiency, accompanied by a corresponding 9.25 % reduction in cooling power. Furthermore, under asymmetric tip clearance conditions, changes in radial clearance have a much greater impact on the performance of CNTE than modifications to axial clearance. Additionally, rotational speed significantly impacts turboexpander performance, with an optimal rotational speed range existing to maximize both isentropic efficiency and cooling power. In summary, this study provides novel insights and a theoretical foundation for optimizing the operational parameters and structural design of cryogenic neon turboexpanders.

低温氖气涡轮膨胀器（CNTE）是氖气克劳德循环制冷机的核心部件。全面了解其内部流动损失机制对于进一步提高CNTE性能至关重要。本研究采用计算流体力学（CFD）模拟和熵产分析相结合的方法研究了CNTE内部的流动特性和能量耗散机制。数值计算结果表明，约91.5%的总熵产来自叶轮和扩散器部件，主要损失机制是叶尖间隙泄漏流与主流界面处的湍流能量耗散。定量分析表明，当叶尖间隙从0 mm扩大到0.6 mm时，等熵效率下降11.13%，冷却功率相应降低9.25%。此外，在非对称叶尖间隙条件下，径向间隙的变化对CNTE性能的影响远大于轴向间隙的变化。此外，转速对涡轮膨胀机的性能有显著影响，存在一个最佳转速范围，以最大限度地提高等熵效率和冷却功率。本研究为低温氖气涡轮膨胀器的运行参数优化和结构设计提供了新的思路和理论基础。

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引用次数: 0

Research on health monitoring of extreme low-temperature equipment 极低温设备健康监测研究

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-10-22 DOI: 10.1016/j.cryogenics.2025.104218

Haojian Su , Zekun Wang , Liancheng Xie , Mingyue Jiang

Full-lifecycle health monitoring of extreme low-temperature equipment heavily depends on the stability of the cryogenic mechanical behavior of core structural materials. Notably, Fe-Mn-C series high-manganese steels stand as key candidate material for extreme low-temperature scenarios at 4.2 K. To address three critical challenges for this material system—i.e., the lack of 4.2 K constitutive models, multi-scale modeling bottlenecks, and insufficient local monitoring—that directly limit its health monitoring, this study targets Fe-22 wt% Mn-1 wt% C-0.3 wt% Cu high-manganese austenitic steel to systematically investigate its 4.2 K constitutive behavior and microscale deformation mechanisms. The results are as follows: (1) At 4.2 K, the material exhibits a serrated stress–strain response in the plastic stage, characterized by “variable period, amplitude, and equilibrium position”; this behavior is dominated by the synergy of low-frequency (<60 Hz) dynamic strain aging (DSA) and mechanical twinning. (2) 4.2 K-adapted cryogenic digital image correlation (DIC) technology reveals that the material exhibits differentiated strain distributions across temperature ranges, providing direct visual evidence for risk zone localization in health monitoring. (3) Microscopic characterization confirms that the hierarchical twin structure at 4.2 K is the core mechanism sustaining the material’s strength-plasticity balance; based on this, a correlation model linking “macroscopic strain distribution and microscopic twin evolution” is established. Leveraging these results, this study establishes a foundational 4.2 K constitutive model incorporating DSA-twinning coupling terms. This model enables quantitative support for “stress-strain-failure risk” analysis in extreme low-temperature equipment health monitoring, facilitating the advancement of monitoring systems from “macroscopic evaluation” to “precision early warning”.

极低温设备的全生命周期健康监测在很大程度上取决于核心结构材料的低温力学行为的稳定性。值得注意的是，Fe-Mn-C系列高锰钢是4.2 K极端低温场景的关键候选材料。为了解决该材料系统面临的三个关键挑战，即：本研究以Fe-22 wt% Mn-1 wt% C-0.3 wt% Cu高锰奥氏体钢为研究对象，对其4.2 K本构行为和微尺度变形机制进行了系统研究。结果表明：(1)在4.2 K时，材料在塑性阶段表现出“变周期、变振幅、变平衡位置”的锯齿形应力应变响应；这种行为主要是低频（60 Hz）动态应变时效（DSA）和机械孪晶的协同作用。(2) 4.2 k适应低温数字图像相关（DIC）技术显示，材料在不同温度范围内呈现出不同的应变分布，为健康监测中的风险区域定位提供了直接的视觉证据。(3)微观表征证实了4.2 K时的分层孪晶结构是维持材料强度塑性平衡的核心机制；在此基础上，建立了“宏观应变分布与微观孪晶演化”的关联模型。利用这些结果，本研究建立了一个包含dsa -孪生耦合项的基础4.2 K本构模型。该模型可为极低温设备健康监测中的“应力-应变-失效风险”分析提供定量支持，促进监测系统从“宏观评价”向“精准预警”推进。

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引用次数: 0

Numerical investigation of the performance and gas flow characteristics of a novel low-temperature-driven multistage Knudsen pump 一种新型低温驱动多级克努森泵性能及气体流动特性的数值研究

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-10-19 DOI: 10.1016/j.cryogenics.2025.104215

Tiantian Xiao , Yi Liao , Xuming Liu , Changzhao Pan

The Knudsen pump, which operates based on the thermal transpiration effect and contains no moving parts, offers a promising solution for microfluidic transport. Its ability to function at low temperatures is particularly advantageous for applications such as hydrogen transportation, which help mitigate leakage risks, and space cryogenic systems, which require high reliability and compact design. This paper develops a numerical model of the low-temperature-driven Knudsen pump (LT-KP) based on the Navier-Stokes equations, incorporating velocity slip and temperature jump boundary conditions. The model simulates and evaluates the pressurization performance and the internal gas flow characteristics of the Knudsen pump over a temperature range extending from liquid nitrogen to room temperature. The simulation results indicate that a single-stage LT-KP can achieve a compression ratio of 1.02 under a temperature gradient of 223 K and an initial pressure of 1 atm. The study further investigates the impact of structural and operational parameters, including the number of stages, temperature gradients, gas rarefaction degree, microchannel dimensions, and gas types. More importantly, a design scheme for a closed-cycle dilution refrigerator incorporating LT-KP is proposed. The simulation results demonstrate that the 10-stage LT-KP, driven by the cascaded temperature gradients of 4 K-40 K and 40 K-300 K, can achieve pressurization from 5 mbar to 200 mbar. This research addresses the knowledge gap regarding Knudsen pump operation in cryogenic environments and provides valuable guidance for its application in refrigeration systems.

Knudsen泵基于热蒸腾效应运行，不包含任何运动部件，为微流体输送提供了一个有前途的解决方案。它在低温下工作的能力对于氢运输和空间低温系统等应用特别有利，这有助于降低泄漏风险，这需要高可靠性和紧凑的设计。基于Navier-Stokes方程，考虑速度滑移和温度跳变边界条件，建立了低温驱动Knudsen泵（LT-KP）的数值模型。该模型模拟和评估了从液氮到室温温度范围内Knudsen泵的增压性能和内部气体流动特性。仿真结果表明，在223 K的温度梯度和1 atm的初始压力下，单级LT-KP可以实现1.02的压缩比。该研究进一步研究了结构和操作参数的影响，包括级数、温度梯度、气体稀薄度、微通道尺寸和气体类型。更重要的是，提出了一种含有LT-KP的闭式循环稀释制冷机的设计方案。仿真结果表明，在4 K-40 K和40 K-300 K的级联温度梯度驱动下，10级LT-KP可以实现5 mbar到200 mbar的增压。本研究解决了关于克努森泵在低温环境中运行的知识差距，并为其在制冷系统中的应用提供了有价值的指导。

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引用次数: 0

Study on the degradation of current-carrying performance of YBCO multi-filamentary tapes prepared by reel-to-reel ultraviolet picosecond laser cutting under pure torsion mode 纯扭转模式下卷对卷紫外皮秒激光切割制备的YBCO多丝带载流性能退化研究

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-10-17 DOI: 10.1016/j.cryogenics.2025.104213

Jiulong Zhang , Zuoguang Li , Jingfeng Zhang , Zhiheng Ren , Jinhao Shi , Huan Jin , Jinggang Qin , Chao Zhou , Shaoqing Wei , Zhan Zhang

YBCO multi-filamentary tapes’ current-carrying performance is susceptible to torsional stress during cable and magnet fabrication. In this study, commercial YBCO tapes from Shanghai Superconductor Technology Co., Ltd. were cut using a reel-to-reel ultraviolet picosecond laser cutting device developed by our group to fabricate 2-filament, 6-filament, and 10-filament multi-filamentary tapes. Additionally, some of the multi-filamentary tapes were encapsulated using the copper-plating re-encapsulation process developed by our group. The current-carrying performance degradation behavior of non-striated tapes, unencapsulated multi-filamentary tapes, and re-encapsulated copper-plated multi-filamentary tapes under pure torsion mode was systematically analyzed. The results show that the degradation behavior of multi-filamentary tapes is strongly dependent on the number of filaments. Specifically, the critical current degradation rates of unencapsulated non-striated tapes and unencapsulated 2-filament tapes are 12.11 % and 12.43 % respectively when the shear strain reaches 0.4125 %. In contrast, unencapsulated 6-filament and unencapsulated 10-filament tapes exhibit degradation rates of 11.69 % and 20.96 % respectively at a lower strain (0.375 %). For samples subjected to single-side copper-plated re-encapsulation with a thickness of 10 μm, the pattern of performance degradation is essentially consistent with that of the samples before copper-plated re-encapsulation, but their overall ability to withstand shear strain is improved by approximately 0.1 %. Macroscopic observations indicate that the surface of the tapes remains smooth without delamination after torsion; however, the “triangular” deformation feature reveals uneven internal stress distribution, suggesting that the superconducting layer may have incurred microscopic damage..

YBCO多丝带的载流性能在电缆和磁体制造过程中容易受到扭转应力的影响。本研究以上海超导科技有限公司生产的YBCO商用胶带为材料，采用本课目研制的卷对卷紫外皮秒激光切割装置，分别制备了2丝、6丝和10丝多丝胶带。此外，部分多纤带采用本课题组开发的镀铜再封装工艺进行封装。系统分析了纯扭转模式下无条纹带、未封装多丝带和再封装镀铜多丝带载流性能的退化行为。结果表明，多丝带的降解行为与多丝带的数量密切相关。其中，当剪切应变达到0.4125%时，未封装的无条纹带和未封装的2丝带的临界电流降解率分别为12.11%和12.43%。相比之下，未封装的6丝带和未封装的10丝带在较低应变（0.375%）下的降解率分别为11.69%和20.96%。对于厚度为10 μm的单面镀铜重包覆样品，其性能下降模式与镀铜重包覆前基本一致，但其整体抗剪切应变能力提高了约0.1%。宏观观察表明，扭转后胶带表面保持光滑，无分层现象；然而，“三角形”变形特征显示出内部应力分布不均匀，表明超导层可能发生了微观损伤。

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引用次数: 0

Energy conversion and loss characteristics of multi-stage cryogenic submerged pumps based on power density evolution model 基于功率密度演化模型的多级低温潜水泵能量转换及损耗特性研究

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-10-10 DOI: 10.1016/j.cryogenics.2025.104211

Jinjie Wang , Qile Ren , Honggang Wen , Zuchao Zhu , Xiaojun Li

Cryogenic submerged pumps (CSPs) are imperative for the efficient transport of cryogenic fluids; however, their multi-stage energy conversion mechanisms remain insufficiently understood under extreme operating conditions. This study aims to quantitatively elucidate the internal flow field and energy transfer characteristics of a two-stage CSP by developing an energy conversion and loss analysis method based on power density distribution. This method integrates high-fidelity numerical simulations and experimental validation using liquid nitrogen. The results reveal that the first-stage impeller is highly sensitive to inlet flow disturbances under off-design conditions, with local flow separation increasing turbulence intensity and energy dissipation; the deviation proportion (DP) in certain channels exceeds 15%. Conversely, the second-stage impeller exhibits a more uniform power density distribution and maintains stable outlet pressure even at 1.4Q_d, where its kinetic energy increment extends to a streamline distance of 0.36 compared to 0.2 in the first stage. Guide vanes account for 65 % of the total turbulent dissipation power and 59 % of wall friction loss, with peak kinetic-to-pressure energy conversion efficiency occurring at a streamline distance of 0.3. Both the impeller and guide vanes exhibit similar energy transfer processes: power density increases slightly at the inlet, decreases gradually along the channel, and rebounds near the outlet. These findings clarify inter-stage synergy and loss mechanisms while providing quantitative design guidance for optimising impeller–guide vane matching, thereby improving overall efficiency and expanding the high-efficiency operating range of multi-stage CSPs.

低温潜水泵（CSPs）是低温流体高效输送的必要条件；然而，在极端操作条件下，它们的多级能量转换机制仍然没有得到充分的了解。本研究旨在通过建立一种基于功率密度分布的能量转换和损失分析方法，定量地阐明两级光热发电的内部流场和能量传递特性。该方法将高保真数值模拟与液氮实验验证相结合。结果表明：在非设计工况下，一级叶轮对进口气流扰动高度敏感，局部流动分离增加了湍流强度和能量耗散；某些信道的偏差比例（DP）超过15%。相反，二级叶轮的功率密度分布更加均匀，即使在1.4Qd时也保持稳定的出口压力，其动能增量从一级的0.2扩展到0.36的流线距离。导叶占总湍流耗散功率的65%，占壁面摩擦损失的59%，动压能量转换效率在流线距离为0.3时达到峰值。叶轮和导叶均表现出相似的能量传递过程：功率密度在进口处略有增加，沿通道逐渐降低，在出口附近反弹。这些发现阐明了级间协同和损失机制，同时为优化叶轮-导叶匹配提供了定量设计指导，从而提高了多级csp的整体效率，扩大了其高效运行范围。

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引用次数: 0

Effect of hole pattern on high temperature superconducting wire using metal stitching for high-speed quench propagation 孔型对金属拼接高温超导线高速淬火传播的影响

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-10-06 DOI: 10.1016/j.cryogenics.2025.104212

Rock Kil Ko, Hyun Woo Noh, Tae Hyung Koo, Dong Woo Ha, Young Min Seo

In this study, we investigated the influence of hole pattern on the quench propagation behavior of high-temperature superconducting (HTS) wires utilizing a metal stitching technique. A nano-second laser processing system was used to fabricate precise micro-hole patterns through the metal and insulation layers of the HTS conductor. To evaluate the quench performance, HTS wires were prepared with various hole spacing patterns (5 cm, 2.5 cm, and 1 cm) and compared with an unmodified original wire. The results showed that as the hole spacing decreased, the decay of the central magnetic field after quench became significantly faster. In particular, the sample with 2.5 cm spacing exhibited a sharp drop in central field from 44 G to 3 G after quench. Additionally, a metal-insulated coil incorporating a 2 cm-spacing metal stitching pattern demonstrated a magnetic flux density decay rate exceeding 40 G/sec, indicating improved responsiveness in quench detection and protection systems. These findings confirm the potential of metal stitching as a structural strategy to enhance the quench safety in HTS applications.

在本研究中，我们利用金属拼接技术研究了孔模式对高温超导导线淬火传播行为的影响。利用纳秒激光加工系统在高温超导导体的金属层和绝缘层上加工出精密的微孔图案。为了评估淬火性能，制备了不同孔间距模式（5厘米，2.5厘米和1厘米）的高温超导丝，并与未修改的原始丝进行了比较。结果表明：随着孔间距的减小，淬火后的中心磁场衰减速度明显加快；特别是2.5 cm的试样，淬火后中心磁场从44 G急剧下降到3 G。此外，采用2厘米间距金属拼接模式的金属绝缘线圈显示出超过40 G/sec的磁通密度衰减率，表明淬灭检测和保护系统的响应性得到改善。这些发现证实了金属拼接作为一种结构策略的潜力，以提高高温超导应用中的淬火安全性。

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引用次数: 0

CFD validation of k-site tank self-pressurization under varying fill levels and heat fluxes with different turbulence models 不同湍流模型下不同液位和热通量下k-site罐自压的CFD验证

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-10-04 DOI: 10.1016/j.cryogenics.2025.104210

Olga Kartuzova , Mohammad Kassemi , Daniel Hauser

Accurate prediction of cryogenic tank self-pressurization is critical for NASA’s short- and long-duration missions, where heat leakage into storage systems occurs through insulation, structural supports, and penetrations. To address this need, a two-phase CFD model was developed to simulate the self-pressurization of a cryogenic storage tank partially filled with liquid hydrogen. The model employed the Volume-Of-Fluid (VOF) approach to capture two-phase flow behavior, incorporating interfacial heat, mass and momentum transfer between the liquid and vapor phases. Validation was carried out against self-pressurization experiments performed using the K-site flightweight hydrogen storage tank at NASA Glenn Research Center. Initial validation focused on a 49 % liquid fill level followed by extension to additional fill levels of 29 % and 83 %, studied in the experiment. Laminar and turbulent simulations were performed, along with conjugate heat transfer, to evaluate pressurization dynamics across different operating conditions. Numerical results for tank pressures and fluid temperature are compared with experimental data under external tank heat fluxes of 3.5 and 2.0 W/m². The effects of turbulence modeling, liquid fill level, and localized heat leaks through instrumentation penetrations are analyzed and discussed in detail.

低温储罐自增压的准确预测对于NASA的短期和长期任务至关重要，在这些任务中，热泄漏会通过绝缘、结构支撑和穿透进入存储系统。为了满足这一需求，开发了一个两相CFD模型来模拟部分充满液态氢的低温储罐的自加压。该模型采用了流体体积（VOF）方法来捕捉两相流动行为，结合了液相和气相之间的界面热量、质量和动量传递。在美国宇航局格伦研究中心的k站点飞行重量储氢罐上进行了自加压实验，验证了该方法的有效性。最初的验证集中在49%的液体填充水平，随后扩展到29%和83%的额外填充水平，在实验中研究。层流和湍流模拟以及共轭传热进行了模拟，以评估不同操作条件下的增压动力学。在罐外热通量为3.5和2.0 W/m2时，对罐内压力和流体温度的数值计算结果与实验数据进行了比较。详细分析和讨论了湍流模拟、液体填充水平和仪器穿透局部热泄漏的影响。

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引用次数: 0

Analysis and experimental validation of a design method for 5 K precooled Joule-Thomson coolers 5k预冷焦耳-汤姆逊制冷机设计方法的分析与实验验证

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-09-30 DOI: 10.1016/j.cryogenics.2025.104209

Giorgio Ghilardi, Sangkwon Jeong

A 2-stage precooled Joule-Thomson (J-T) refrigerator for potential cooling of superconducting nanowire single photon detector (SNSPD) is conceived, analyzed and tested. In the analysis, theoretical tools aimed at aiding the design process are presented. The effect of the precooling temperatures is discussed in detail. To validate the analysis, an experimental apparatus is built employing a commercial Gifford-McMahon (G-M) cryocooler. The system is built by repurposing commercial compressors for use with ⁴He. The complete system is composed of the G-M auxiliary cryocooler; the J-T refrigerator heat exchangers and expansion orifice, and the compressors with an oil removal system (ORS). The model associated with the analysis predicted the cold-tip temperature with a maximum error lower of 0.5 K. The whole system achieved a cooling power of 10 mW at 5 K.

设计了一种用于超导纳米线单光子探测器（SNSPD）潜在冷却的两级预冷焦耳-汤姆逊（J-T）制冷机，并对其进行了分析和测试。在分析中，提出了旨在帮助设计过程的理论工具。详细讨论了预冷温度的影响。为了验证分析结果，采用商用吉福德-麦克马洪（G-M）制冷机建立了实验装置。该系统是通过重新利用商用压缩机与4He一起使用而构建的。整套系统由G-M辅助制冷机组成；J-T制冷机热交换器和膨胀孔，以及带有除油系统（ORS）的压缩机。与分析相关联的模型预测冷尖温度的最大误差小于0.5 K。整个系统在5k时达到了10mw的冷却功率。

引用次数: 0

Comparative study of threshold voltage extraction methods for 55 nm CMOS technology at liquid helium temperature 55 nm CMOS工艺在液氦温度下阈值电压提取方法的比较研究

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-09-30 DOI: 10.1016/j.cryogenics.2025.104208

Gaohao Chen , Ao Tan , Cheng Wang , Jie Ning , Xueye Hu , Futian Liang , Xinzhe Wang , Jinhong Wang , Shubin Liu

Accurate determination of threshold voltage (

V_{th}

) is critical for MOSFET characterization and modeling, especially for emerging applications in cryogenic electronics, such as quantum computing and advanced scientific instrumentation. This paper presents a systematic comparative evaluation of multiple threshold voltage extraction methods applied to a commercial 55 nm bulk CMOS technology at liquid helium temperature (

\sim

4 K). We examine and adapt conventional extraction techniques—including Constant Current (CC), Linear Extrapolation (LE), Y-function (Yfunc), Transconductance Linear Extrapolation (GMLE), Second Derivative (SD), Third Derivative (TD), Transition-based (TM, NMID, NRH), and Transconductance-to-Current Ratio (TCR)-based methods—and assess their performance in terms of consistency, robustness against measurement noise, and applicability at cryogenic temperatures. Results indicate significant method-dependent variability in extracted threshold values at 4 K, reflecting fundamental differences in how each method handles cryogenic-specific effects such as dopant freeze-out and mobility variations. Through careful comparative analysis, we identify the most reliable and accurate extraction methods for low-temperature conditions, specifically SD, LE, TM, TD, GMLE, fitLE (fitted linear extrapolation), and Y-function, offering practical recommendations to improve device modeling accuracy and reliability for cryogenic CMOS circuits.

准确确定阈值电压（Vth）对于MOSFET的表征和建模至关重要，特别是对于低温电子领域的新兴应用，如量子计算和先进的科学仪器。本文提出了应用于商用55nm块体CMOS技术的多种阈值电压提取方法在液氦温度（~ 4 K）下的系统比较评估。我们研究并调整了传统的提取技术，包括恒流（CC）、线性外推（LE）、y函数（Yfunc）、跨导线性外推（GMLE）、二阶导数（SD）、三阶导数（TD）、基于过渡（TM、NMID、NRH）和基于跨导电流比（TCR）的方法，并评估了它们在一致性、对测量噪声的鲁棒性以及在低温下的适用性方面的性能。结果表明，在4 K时提取的阈值存在显著的方法依赖差异，反映了每种方法在处理掺杂剂冻结和迁移率变化等低温特异性效应方面的根本差异。通过仔细的对比分析，我们确定了在低温条件下最可靠和准确的提取方法，特别是SD， LE， TM， TD， GMLE, fitLE（拟合线性外推）和y函数，为提高低温CMOS电路的器件建模精度和可靠性提供了实用建议。

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引用次数: 0

Hydrogen liquefaction by active magnetic regenerative refrigeration 主动磁蓄热式制冷氢液化

IF 2.1 3区工程技术 Q3 PHYSICS, APPLIED

Cryogenics

Pub Date : 2025-09-28 DOI: 10.1016/j.cryogenics.2025.104205

Koji Kamiya , Kyohei Natsume , Akira Uchida , Takenori Numazawa , Tsuyoshi Shirai , Akiko T. Saito , Koichi Matsumoto , Shinji Masuyama

Magnetic refrigeration is a cooling method that utilizes the magnetocaloric effect. The magnetocaloric effect induces temperature changes by varying the magnetic moment in response to changes in a magnetic field, eliminating the need for compression work as seen in conventional gas refrigerators. This enables high-efficiency cooling, making it suitable for cooling and liquefaction of cryogenic gases. In this study, we focused on an Active Magnetic Refrigeration (AMR) system, one of the magnetic refrigeration methods, capable of operating over a wide temperature range, and fabricated a dedicated AMR system for hydrogen liquefaction. The AMR developed in this study achieved a cooling power of 7.34 W and a relative Carnot efficiency of 60.5 %.

磁制冷是一种利用磁热效应的制冷方法。磁热效应通过改变磁矩来响应磁场的变化，从而引起温度的变化，从而消除了传统燃气冰箱中所看到的压缩工作的需要。这可以实现高效冷却，使其适用于低温气体的冷却和液化。在这项研究中，我们重点研究了一种能够在宽温度范围内工作的磁致冷（AMR）系统，并制造了一种用于氢液化的专用AMR系统。本研究开发的AMR的冷却功率为7.34 W，相对卡诺效率为60.5%。

引用次数: 0