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Updated: Jun 14, 2026
13:02
Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow
Published on: February 27, 2016
Turbulent cascade at 1 AU in high cross-helicity flows
Charles W Smith1, Joshua E Stawarz, Bernard J Vasquez
1Physics Department, University of New Hampshire, Durham, New Hampshire, USA. Charles.Smith@unh.edu
Physical Review Letters
|April 7, 2010
Summary
High cross-field correlation in solar wind plasma causes a surprising energy back-transfer. This finding helps explain persistent observations in solar wind physics.
Area of Science:
- Plasma Physics
- Solar Wind Dynamics
- Magnetohydrodynamics (MHD)
Background:
- Solar wind plasma exhibits persistent large cross-field correlations between velocity and magnetic field fluctuations.
- Understanding energy transfer mechanisms is crucial for solar wind physics.
Purpose of the Study:
- To analyze the scaling of mixed third moments of velocity and magnetic fluctuations.
- To investigate energy cascade rates and their dependence on cross-field correlations.
- To explain the observed dominance of outward-propagating solar wind components.
Main Methods:
- Analysis of scaling laws for mixed third moments of velocity and magnetic field fluctuations.
- Derivation and analysis of energy cascade rates from observed scaling.
- Correlation analysis between velocity and magnetic field fluctuations.
Main Results:
- Energy cascade rates show a strong dependence on cross-field correlation.
- Negative cascade rates for outward-propagating component, total energy, and cross-helicity observed when correlation exceeds 75%.
- Evidence of energy back-transfer from small to large scales in the dominant component.
Conclusions:
- Energy transfer reinforces the dominance of the outward-propagating solar wind component.
- The observed energy back-transfer mechanism may explain persistent large cross-field correlations in the solar wind.
- Findings contribute to a deeper understanding of solar wind turbulence and evolution.
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