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Updated: Mar 28, 2026
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Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section
Published on: July 19, 2016
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Hindered Energy Cascade in Highly Helical Isotropic Turbulence
Rodion Stepanov1,2, Ephim Golbraikh3, Peter Frick1
1Institute of Continuous Media Mechanics, Korolyov 1, Perm 614013, Russia.
Physical Review Letters
|December 20, 2015
Summary
This study introduces a new model for turbulent energy flow, incorporating fluid helicity. Numerical simulations reveal that helicity can hinder energy transfer, creating a "helical bottleneck" in the inertial energy spectrum.
Area of Science:
- * Fluid dynamics
- * Turbulence theory
- * Statistical physics
Background:
- * Conventional turbulent energy cascade models (Richardson-Kolmogorov phenomenology) neglect vortex topology and helicity.
- * Helicity is known to influence large-scale magnetic fields but its effect on small-scale energy cascades was unobserved.
- * Understanding helicity's role is crucial for a complete theory of turbulence.
Purpose of the Study:
- * To propose a generalized phenomenology for isotropic turbulence that includes helicity's spectral distribution.
- * To investigate the impact of helicity on the direct turbulent energy cascade.
- * To identify and characterize new effects of helicity on spectral energy transfer.
Main Methods:
- * Development of a generalized phenomenology for helical turbulence.
- * High Reynolds number numerical simulations using a shell model.
- * Analysis of energy and helicity spectral distributions.
Main Results:
- * Demonstrated a novel helicity effect that hinders spectral energy transfer.
- * Observed energy accumulation and redistribution to maintain a constant energy flux.
- * Identified the
- helical bottleneck
- effect in the inertial interval of the energy spectrum.
- * Modeled energy injection at large scales with helicity sources distributed across all scales.
Conclusions:
- * The proposed generalized phenomenology accurately describes helical turbulence.
- * Helicity significantly impacts the energy cascade, contrary to previous assumptions.
- * The helical bottleneck effect offers new insights into energy transfer dynamics in turbulent systems.
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