Stereoscopic visualization study of turbulence and vortex-tangle dynamics in He II

He II 中湍流和涡旋缠结动力学的立体可视化研究

• 批准号: 2100790
• 负责人: Wei Guo
• 金额: $ 52.15万
• 依托单位: Florida State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2100790&HistoricalAwards=false
• 关键词: Stereoscopic; visualization; study; turbulence; vortex

Non-Technical Abstract: When liquid helium is cooled to below about -271 degrees Celsius, it becomes a superfluid (called He II), which can do things that other fluids cannot, such as flowing through a narrow capillary without apparent friction and climbing over container walls despite the gravity. The fascinating hydrodynamics of He II has many important applications. For instance, it supports an extremely efficient heat-transport mode called thermal counterflow and therefore has been widely utilized as a coolant material in scientific instruments. When stirred, He II can also create vortex tubes which are essentially tiny tornadoes with thin hollow cores. Understanding the dynamics of a tangle of vortex tubes can benefit the study of various physical systems such as neutron stars that consist of neutron-pair superfluid. In this project, the research team aims to explore some predicted anomalous behaviors in counterflow turbulence and to visualize the vortex tubes in He II using advanced three-dimensional flow visualization techniques. This research can produce fundamental knowledge indispensable for better applications of He II. The research team consists of both postdoctoral researchers and graduate students. Through the project, the team members are expected to gain valuable knowledge in fluid dynamics, cryogenics, and laser technologies. The skills they learn through the research training are also crucial for their success in today's job market. In addition, the research team plans to conduct educational demonstrations involving cryogenic fluids in various outreach programs at the National High Magnetic Field Laboratory. The PI is also committed to serve the research community by organizing workshop and conferences to engage junior researchers. Technical Abstract:The current research work consists of: 1) a stereoscopic molecular tagging velocimetry (MTV) study of the anomalous anisotropy in He II counterflow turbulence, and 2) an exploration of the vortex tangle dynamics using a scanning particle tracking velocimetry (PTV) method. The stereoscopic MTV system, which incorporates a unique double-line optical setup, is developed as the first-of-its-kind equipment in quantum turbulence research. It offers the capability of making unambiguous measurements of the normal-fluid velocity field and its spatial correlations in the coupled two-fluid system, which breaks the ground for solving various challenging problems. The study of the anomalous anisotropy in He II counterflow turbulence is expected to produce experimental data that are critical for the development of a complete theoretical understanding of this complex doubly turbulent system. Such an understanding not only advances the knowledge of turbulence in general but also aids the cryogenic engineers in designing more efficient He II based cooling systems. The scanning PTV system to be developed enables real-time imaging of quantized vortex tangles in three-dimensional space, which offers a great opportunity for vortex research that is not possible otherwise. The planned research on exploring the vortex-reconnection scaling, vortex-velocity correlations, and vortex trajectory statistics should produce important new knowledge needed for the development of an advanced statistical model of quantum turbulence.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

非技术摘要：当液体氦气冷却至约-271摄氏度以下时，它变成了超氟（称为HE II），它可以做其他流体无法做的事情，例如，尽管有重力，但仍不明显的毛茸茸而没有明显的摩擦并爬过容器壁。 HE II的引人入胜的流体动力学具有许多重要的应用。例如，它支持一种非常有效的热传输模式，称为热逆流，因此已被广泛用作科学仪器中的冷却剂材料。当搅拌时，他还可以创建涡流管，这本质上是带有薄的空心芯的微小龙卷风。了解涡流管缠结的动力学可以使各种物理系统的研究（如由中子对超氟组成的中子恒星）有益。在这个项目中，研究团队旨在探索一些预测的逆流湍流中的异常行为，并使用先进的三维流动可视化技术在HE II中可视化He II中的涡流管。这项研究可以为HE II的更好地应用提供基本知识必不可少的知识。研究小组由博士后研究人员和研究生组成。通过该项目，团队成员有望在流体动力学，低温和激光技术方面获得宝贵的知识。他们通过研究培训学习的技能对于他们在当今就业市场上的成功也至关重要。此外，研究小组计划在国家高磁场实验室的各种外展计划中进行涉及低温流体的教育示范。 PI还致力于通过组织研讨会和会议来吸引初级研究人员来为研究社区服务。 技术摘要：当前的研究工作包括：1）对He II逆流湍流中异常各向异性的立体分子标记速度法（MTV）研究，以及2）使用扫描粒子跟踪Velocimetry（PTV）方法对涡流缠结动力学的探索。立体MTV系统结合了独特的双线光学设置，是量子湍流研究中的首个设备开发的。它提供了对正常流体速度场及其在耦合的两流体系统中的空间相关性进行明确测量的能力，这打破了解决各种具有挑战性的问题的基础。 HE II逆流湍流中对异常各向异性的研究有望产生实验数据，这对于对这一复杂的湍流系统的完整理论理解至关重要。这种理解不仅可以提高湍流的知识，而且还有助于低温工程师设计基于II的更有效的冷却系统。要开发的扫描PTV系统可以在三维空间中对量化涡流缠结的实时成像，这为涡旋研究提供了绝佳的机会，否则就不可能。探索涡流连接缩放，涡流 - 速度相关性和涡流轨迹统计的计划研究应产生量子湍流的先进统计模型所需的重要新知识。这奖反映了NSF的法规任务，并被认为是通过基金会的知识优点和宽广的范围来评估的，并值得通过评估来进行评估。

项目成果

Vinen’s Latest Thoughts on the “Bump” Puzzle in Decaying He II Counterflow Turbulence

维宁对衰变 He II 逆流湍流中“碰撞”难题的最新思考

• DOI: 10.1007/s10909-023-02961-7
• 发表时间: 2023
• 期刊: Journal of Low Temperature Physics
• 影响因子: 2
• 作者: Guo, Wei;Kanai, Toshiaki
• 通讯作者: Kanai, Toshiaki

Velocity circulation intermittency in finite-temperature turbulent superfluid helium

有限温度湍流超流氦中的速度循环间歇性

• DOI: 10.1103/physrevfluids.7.104604
• 发表时间: 2022
• 期刊: Physical Review Fluids
• 影响因子: 2.7
• 作者: Müller, Nicolás P.;Tang, Yuan;Guo, Wei;Krstulovic, Giorgio
• 通讯作者: Krstulovic, Giorgio

Universal Anomalous Diffusion of Quantized Vortices in Ultraquantum Turbulence

超量子湍流中量子化涡旋的普遍反常扩散

• DOI: 10.1103/physrevlett.129.025301
• 发表时间: 2022
• 期刊: Physical Review Letters
• 影响因子: 8.6
• 作者: Yui, Satoshi;Tang, Yuan;Guo, Wei;Kobayashi, Hiromichi;Tsubota, Makoto
• 通讯作者: Tsubota, Makoto

Flow of the normal component of He-II about bluff objects observed with He2* excimers

• DOI: 10.1103/physrevb.107.174501
• 发表时间: 2023-05
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: X. Wen;J. Pierce;N. Lavrik;S. J. Randolph;Weisi Guo;M. Fitzsimmons

Single electrons on solid neon as a solid-state qubit platform

固体氖上的单电子作为固态量子位平台

• DOI: 10.1038/s41586-022-04539-x
• 发表时间: 2022
• 期刊: Nature
• 影响因子: 64.8
• 作者: Zhou, Xianjing;Koolstra, Gerwin;Zhang, Xufeng;Yang, Ge;Han, Xu;Dizdar, Brennan;Li, Xinhao;Divan, Ralu;Guo, Wei;Murch, Kater W.
• 通讯作者: Murch, Kater W.