The Role of Inertia in the Onset of Turbulence in a Vortex Filament
The decay of the kinetic energy of a turbulent flow with time is not necessarily monotonic. This is revealed by simulations performed in the framework of discrete mechanics, where the kinetic energy can be transformed into pressure energy or vice versa; this persistent phenomenon is also observed fo...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-01-01
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| Series: | Fluids |
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| Online Access: | https://www.mdpi.com/2311-5521/8/1/16 |
| _version_ | 1797442611596754944 |
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| author | Jean-Paul Caltagirone |
| author_facet | Jean-Paul Caltagirone |
| author_sort | Jean-Paul Caltagirone |
| collection | DOAJ |
| description | The decay of the kinetic energy of a turbulent flow with time is not necessarily monotonic. This is revealed by simulations performed in the framework of discrete mechanics, where the kinetic energy can be transformed into pressure energy or vice versa; this persistent phenomenon is also observed for inviscid fluids. Different types of viscous vortex filaments generated by initial velocity conditions show that vortex stretching phenomena precede an abrupt onset of vortex bursting in high-shear regions. In all cases, the kinetic energy starts to grow by borrowing energy from the pressure before the transfer phase to the small turbulent structures. The result observed on the vortex filament is also found for the Taylor–Green vortex, which significantly differs from the previous results on this same case simulated from the Navier–Stokes equations. This disagreement is attributed to the physical model used, that of discrete mechanics, where the formulation is based on the conservation of acceleration. The reasons for this divergence are analyzed in depth; however, a spectral analysis allows finding the established laws on the decay of kinetic energy as a function of the wave number. |
| first_indexed | 2024-03-09T12:45:27Z |
| format | Article |
| id | doaj.art-00c66b0390244ad2b7f638d5a99bedd1 |
| institution | Directory Open Access Journal |
| issn | 2311-5521 |
| language | English |
| last_indexed | 2024-03-09T12:45:27Z |
| publishDate | 2023-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Fluids |
| spelling | doaj.art-00c66b0390244ad2b7f638d5a99bedd12023-11-30T22:12:57ZengMDPI AGFluids2311-55212023-01-01811610.3390/fluids8010016The Role of Inertia in the Onset of Turbulence in a Vortex FilamentJean-Paul Caltagirone0Bordeaux INP, Arts et Métiers Institute of Technology, University of Bordeaux, CNRS UMR-5295, INRAE, I2M Bordeaux, 33405 Talence, FranceThe decay of the kinetic energy of a turbulent flow with time is not necessarily monotonic. This is revealed by simulations performed in the framework of discrete mechanics, where the kinetic energy can be transformed into pressure energy or vice versa; this persistent phenomenon is also observed for inviscid fluids. Different types of viscous vortex filaments generated by initial velocity conditions show that vortex stretching phenomena precede an abrupt onset of vortex bursting in high-shear regions. In all cases, the kinetic energy starts to grow by borrowing energy from the pressure before the transfer phase to the small turbulent structures. The result observed on the vortex filament is also found for the Taylor–Green vortex, which significantly differs from the previous results on this same case simulated from the Navier–Stokes equations. This disagreement is attributed to the physical model used, that of discrete mechanics, where the formulation is based on the conservation of acceleration. The reasons for this divergence are analyzed in depth; however, a spectral analysis allows finding the established laws on the decay of kinetic energy as a function of the wave number.https://www.mdpi.com/2311-5521/8/1/16turbulence cascadevortex stretchingvortex burstingdiscrete mechanicsconservation of accelerationHelmholtz–Hodge decomposition |
| spellingShingle | Jean-Paul Caltagirone The Role of Inertia in the Onset of Turbulence in a Vortex Filament Fluids turbulence cascade vortex stretching vortex bursting discrete mechanics conservation of acceleration Helmholtz–Hodge decomposition |
| title | The Role of Inertia in the Onset of Turbulence in a Vortex Filament |
| title_full | The Role of Inertia in the Onset of Turbulence in a Vortex Filament |
| title_fullStr | The Role of Inertia in the Onset of Turbulence in a Vortex Filament |
| title_full_unstemmed | The Role of Inertia in the Onset of Turbulence in a Vortex Filament |
| title_short | The Role of Inertia in the Onset of Turbulence in a Vortex Filament |
| title_sort | role of inertia in the onset of turbulence in a vortex filament |
| topic | turbulence cascade vortex stretching vortex bursting discrete mechanics conservation of acceleration Helmholtz–Hodge decomposition |
| url | https://www.mdpi.com/2311-5521/8/1/16 |
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