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Updated: Aug 14, 2026
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Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Intermittency of acceleration in isotropic turbulence
1Department of Mechanical Engineering, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749, Korea.
Summary
Intermittent, high-magnitude acceleration in isotropic turbulence is linked to vortex filament rotation. This finding connects to centripetal forces and local energy dissipation dynamics in turbulent flows.
Area of Science:
- Fluid Dynamics
- Turbulence Research
- Computational Physics
Background:
- Turbulence exhibits intermittent bursts of high acceleration.
- Understanding acceleration intermittency is key to turbulence modeling.
- Previous studies noted similar phenomena in near-wall turbulence.
Purpose of the Study:
- Investigate the spatial and dynamic origins of acceleration intermittency in isotropic turbulence.
- Explore the relationship between vortex dynamics, dissipation, and acceleration.
- Correlate findings with existing research on near-wall turbulence.
Main Methods:
- Direct numerical simulation (DNS) of isotropic turbulence.
- Analysis of vortex filament structures and their rotational motion.
- Examination of local dissipation and enstrophy in relation to acceleration.
Main Results:
- Large acceleration magnitudes consistently align with the rotational axes of vortex filaments.
- Acceleration intermittency is driven by the centripetal acceleration from vortex rotation.
- Strong dissipation near vortex filament edges shows weak correlation with enstrophy but strong correlation with acceleration.
Conclusions:
- Vortex rotational dynamics are fundamental to acceleration intermittency in isotropic turbulence.
- Local dissipation is more closely linked to acceleration than to enstrophy in these structures.
- The findings support and extend previous observations in near-wall turbulence studies.
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