Visualization Technique for Determining the Structure Functions of Normal-Fluid Turbulence in Superfluid Helium-4
| Autor: | Daniel McKinsey, W. F. Vinen, Gary G. Ihas, Wei Guo, K. J. Thompson, A. Marakov |
|---|---|
| Rok vydání: | 2012 |
| Předmět: |
Physics
Turbulence Liquid helium Quantum turbulence chemistry.chemical_element Condensed Matter Physics Atomic and Molecular Physics and Optics law.invention Physics::Fluid Dynamics Superfluidity chemistry Flow (mathematics) law General Materials Science Vector field Atomic physics Superfluid helium-4 Helium |
| Zdroj: | Journal of Low Temperature Physics. 171:497-503 |
| ISSN: | 1573-7357 0022-2291 |
| DOI: | 10.1007/s10909-012-0708-2 |
| Popis: | Metastable helium molecules have been shown to be ideal tracers for the study of normal-fluid flow in superfluid 4He above 1 K. These molecules can be visualized using a laser-induced-fluorescence technique. In order to extract quantitative information of the flow field, practical techniques need to be developed to study the density evolution of the molecules with a well defined initial distribution. In an on-going experiment, we use a focused femtosecond laser pulse to create a thin line of $\mathrm{He}^{*}_{2}$ molecules in liquid helium. Such a line of molecules can be easily imaged. Studying the drift and distortion of the molecular line in a turbulent flow shall allow us to measure the instantaneous flow velocity field and hence determine the structure functions of the normal-fluid turbulence. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink