in the repository
URN to cite this document: urn:nbn:de:bvb:703-epub-8188-5
Title data
Bentkamp, Lukas ; Wilczek, Michael:
Temporal large-scale intermittency and its impact on the statistics of turbulence.
In: Journal of Fluid Mechanics.
Vol. 1004
(2025)
.
- A12.
ISSN 0022-1120
DOI der Verlagsversion: https://doi.org/10.1017/jfm.2024.700
![[thumbnail of temporal-large-scale-intermittency-and-its-impact-on-the-statistics-of-turbulence.pdf]](https://epub.uni-bayreuth.de/style/images/fileicons/application_pdf.png) |
|
||||||||
|
Download (1MB)
|
Abstract
Turbulent flows in three dimensions are characterized by the transport of energy from large to small scales through the energy cascade. Since the small scales are the result of the nonlinear dynamics across the scales, they are often thought of as universal and independent of the large scales. However, as famously remarked by Landau, sufficiently slow variations of the large scales should nonetheless be expected to impact small-scale statistics. Such variations, often termed large-scale intermittency, are pervasive in experiments and even in simulations, while differing from flow to flow. Here, we evaluate the impact of temporal large-scale fluctuations on velocity, vorticity and acceleration statistics by introducing controlled sinusoidal variations of the energy injection rate into direct numerical simulations of turbulence. We find that slow variations can have a strong impact on flow statistics, raising the flatness of the considered quantities. We discern three contributions to the increased flatness, which we model by superpositions of statistically stationary flows. Overall, our work demonstrates how large-scale intermittency needs to be taken into account in order to ensure comparability of statistical results in turbulence.
Further data
| Item Type: | Article in a journal |
|---|---|
| Keywords: | intermittency; turbulence theory |
| DDC Subjects: | 500 Science > 530 Physics |
| Institutions of the University: | Faculties > Faculty of Mathematics, Physics und Computer Science > Department of Physics > Chair Theoretical Physics I > Chair Theoretical Physics I - Univ.-Prof. Dr. Michael Wilczek Faculties Faculties > Faculty of Mathematics, Physics und Computer Science Faculties > Faculty of Mathematics, Physics und Computer Science > Department of Physics Faculties > Faculty of Mathematics, Physics und Computer Science > Department of Physics > Chair Theoretical Physics I |
| Language: | English |
| Originates at UBT: | Yes |
| URN: | urn:nbn:de:bvb:703-epub-8188-5 |
| Date Deposited: | 11 Feb 2025 07:56 |
| Last Modified: | 20 Feb 2025 09:42 |
| URI: | https://epub.uni-bayreuth.de/id/eprint/8188 |
Download Statistics