2010/05/31 by Nobumitsu Yokoi
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #Astro and Planetary Science #Dissipation #Economics #Geomagnetism and Paleomagnetism Studies #Helicity #Mechanics #Particle physics #Physics #Production (economics) #Solar and Space Plasma Dynamics #Statistical physics #Thermodynamics #Turbulence #astro-ph.SR #physics.flu-dyn #physics.plasm-ph
paper · pdf · doi:10.1080/14685248.2011.590495
published as Journal of Turbulence, Vol. 12, No. 27, 2011, 1-33 · 37 pages, 4 figures
openalex publication_date 2011/01/01 · arxiv created 2011/07/29 · arxiv updated 2015/03/16 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
It has been recognized that the turbulent cross helicity (correlation between the velocity and magnetic-field fluctuations) can play an important role in several magnetohydrodynamic plasma phenomena such as the global magnetic-field generation, turbulence suppression, and so on. Despite its relevance to the cross-helicity evolution, little attention has been paid to the dissipation rate of the turbulent cross helicity, ϵ W . In this paper, we consider the model expression for ϵ W . In addition to the algebraic model, an evolution equation of ϵ W is proposed on the basis of the statistical analytical theory of inhomogeneous turbulence. A turbulence model with the modeling of ϵ W is applied to the solar-wind turbulence. Numerical results on the large-scale evolution of cross helicity are compared with the satellite observations. It is shown that, as far as the solar-wind application is concerned, the simplest possible algebraic model for ϵ W is sufficient for elucidating the large-scale spatial evolution of the solar-wind turbulence. Dependence of the cross-helicity evolution on the large-scale velocity structures, such as velocity shear and flow expansion, is also discussed.