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：当液氦冷却到约-271摄氏度以下时，它会变成一种超流体（称为He II），它可以做其他流体做不到的事情，例如在没有明显摩擦的情况下流过狭窄的毛细管，以及尽管有重力而爬过容器壁。 He II 迷人的流体动力学具有许多重要的应用。例如，它支持一种称为热逆流的极其高效的热传输模式，因此已广泛用作科学仪器中的冷却剂材料。当搅拌时，He II 还可以产生涡流管，涡流管本质上是具有薄空心核心的微小龙卷风。了解涡管缠结的动力学有助于研究各种物理系统，例如由中子对超流体组成的中子星。在该项目中，研究团队旨在探索逆流湍流中一些预测的异常行为，并使用先进的三维流动可视化技术对 He II 中的涡管进行可视化。这项研究可以产生更好地应用He II所必需的基础知识。研究团队由博士后研究人员和研究生组成。通过该项目，团队成员有望获得流体动力学、低温学和激光技术方面的宝贵知识。他们通过研究培训学到的技能对于他们在当今就业市场的成功也至关重要。此外，研究小组计划在国家高磁场实验室的各种外展项目中进行涉及低温流体的教育演示。 PI 还致力于通过组织研讨会和会议吸引初级研究人员参与，为研究界服务。 技术摘要：目前的研究工作包括：1）He II逆流湍流中反常各向异性的立体分子标记测速（MTV）研究；2）利用扫描粒子跟踪测速（PTV）方法探索涡旋缠结动力学。立体 MTV 系统采用了独特的双线光学装置，是量子湍流研究中首创的设备。它提供了对耦合二流体系统中的法向流体速度场及其空间相关性进行明确测量的能力，这为解决各种具有挑战性的问题奠定了基础。对 He II 逆流湍流中的反常各向异性的研究预计将产生实验数据，这些数据对于发展对这种复杂的双湍流系统的完整理论理解至关重要。这种理解不仅增进了对湍流的一般认识，而且有助于低温工程师设计更高效的 He II 冷却系统。即将开发的扫描PTV系统能够对三维空间中的量子化涡旋缠结进行实时成像，这为涡旋研究提供了前所未有的绝佳机会。计划中的探索涡旋重联尺度、涡旋速度相关性和涡旋轨迹统计的研究应该会产生开发量子湍流先进统计模型所需的重要新知识。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

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

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

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

True Mechanism of Spontaneous Order from Turbulence in Two-Dimensional Superfluid Manifolds

二维超流体流形中湍流自发有序的真实机制

• DOI: 10.1103/physrevlett.127.095301
• 发表时间: 2021
• 期刊: Physical Review Letters
• 影响因子: 8.6
• 作者: Kanai, Toshiaki;Guo, Wei
• 通讯作者: Guo, Wei

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.