Quantification of the Cross-helicity Turbulent Cascade in Compressible MHD Simulations

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F22%3A00562958" target="_blank" >RIV/67985815:_____/22:00562958 - isvavai.cz</a>

Result on the web

<a href="https://hdl.handle.net/11104/0335137" target="_blank" >https://hdl.handle.net/11104/0335137</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3847/1538-4357/ac9281" target="_blank" >10.3847/1538-4357/ac9281</a>

Result language

angličtina

Original language name

Quantification of the Cross-helicity Turbulent Cascade in Compressible MHD Simulations

Original language description

In plasma turbulence, energy and cross helicity are transferred across scales at a constant rate as a consequence of nonlinear interactions. In incompressible magnetohydrodynamics (MHD), the energy cascade rate of both quantities can be computed by means of the temporal evolution of second-order structure functions, known as Karman-Howarth-Monin (KHM) equations. In the present work, we derive the KHM equation to compute the energy cascade rate of cross helicity in compressible MHD. Using three-dimensional direct numerical simulations, we validate the equation and use it to measure the cross-helicity turbulence properties. Our results show a slower development of the cross-helicity cascade with respect to the energy one and the presence of inverse cascades of energy and cross helicity at large scales when in the presence of a strong mean field. We propose the relation of these phenomena with the longer duration of geomagnetic storms after the arrival of solar winds with large cross helicity and the observation of patchy inertial ranges displaying positive and negative cascade rates for certain solar wind intervals.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10308 - Astronomy (including astrophysics,space science)

Project

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Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2022

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Astrophysical Journal

ISSN

0004-637X

e-ISSN

1538-4357

Volume of the periodical

938

Issue of the periodical within the volume

2

Country of publishing house

GB - UNITED KINGDOM

Number of pages

12

Pages from-to

90

UT code for WoS article

000868888000001

EID of the result in the Scopus database

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