Scale dependence of energy transfer in turbulent plasma. Issue 4 (3rd November 2018)

• Record Type: Journal Article
• Authors: Yang, Yan; Wan, Minping; Matthaeus, William H; Sorriso-Valvo, Luca; Parashar, Tulasi N; Lu, Quanming; Shi, Yipeng; Chen, Shiyi
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 482:Issue 4(2019)
• Page Start: 4933
• Page End: 4940
• Publication Date: 2018-11-03
• Subjects: MHD -- plasmas -- turbulence -- solar wind; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/sty2977
• Languages: English
• ISSNs: 0035-8711

Abstract

ABSTRACT: In the context of space and astrophysical plasma turbulence and particle heating, several vocabularies emerge for estimating turbulent energy dissipation rate, including Kolmogorov–Yaglom third-order law and, in its various forms, $\boldsymbol{j}\cdot \boldsymbol{E}$ (work done by the electromagnetic field on particles), and $-\left(\boldsymbol{P} \cdot \nabla \right) \cdot \boldsymbol{u}$ (pressure–strain interaction), to name a couple. It is now understood that these energy transfer channels, to some extent, are correlated with coherent structures. In particular, we find that different energy dissipation proxies, although not point-wise correlated, are concentrated in proximity to each other, for which they decorrelate in a few ion inertial scales. However, the energy dissipation proxies dominate at different scales. For example, there is an inertial range over which the third-order law is meaningful. Contributions from scale bands stemming from scale-dependent spatial filtering show that the energy exchange through $\boldsymbol{j}\cdot \boldsymbol{E}$ mainly results from large scales, while the energy conversion from fluid flow to internal through $-\left(\boldsymbol{P} \cdot \nabla \right) \cdot \boldsymbol{u}$ dominates at small scales.