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Comprehensive interscale energy transfer in homogeneous isotropic turbulence
Jun-Yang Li1, Dong Sun1, Si-Wei Dong1
1State Key Laboratory of Aerodynamics, Mianyang 621000, China.
Physical Review. E
|May 16, 2026
Summary
This study analyzes energy transfer in turbulent flows, revealing how energy moves between different scales. Key findings detail scaling laws and the impact of extreme events on turbulent intermittency.
Area of Science:
- Fluid Dynamics
- Turbulence Research
Background:
- Understanding energy transfer, or the energy cascade, is crucial in forced homogeneous isotropic turbulence.
- Spatial filtering techniques decompose turbulent kinetic energy into various scale components.
Purpose of the Study:
- To derive transport equations for decomposed turbulent kinetic energy components.
- To establish an analytical framework for cross-scale energy transfer mechanisms.
- To investigate scaling laws, stress tensor contributions, model accuracy, and extreme dissipation events.
Main Methods:
- Spatial filtering to decompose turbulent kinetic energy.
- Derivation of transport equations for scale components.
- Leonard decomposition of subfilter stress tensors.
- Analysis of scaling laws and extreme dissipation events.
Main Results:
- Energy primarily transfers from large-scale and subfilter-small-scale to small-scale and subfilter-large-scale components.
- Scaling laws for interscale energy transfer and dissipation rates are elucidated.
- Contributions of Leonard, cross, and Reynolds stress components to energy transfer are quantified across subranges.
- Classical models for interscale energy transfer are validated.
- Extreme dissipation events show small-scale amplification and altered scaling, linked to intermittency.
Conclusions:
- The study provides a comprehensive framework for understanding interscale energy transfer in turbulence.
- Quantified contributions of stress components offer insights into turbulence modeling.
- Findings highlight the role of intermittency in extreme dissipation events and scaling behavior.
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