The ecology of flows and drift wave turbulence in CSDX: A model
| Autor: | George Tynan, Patrick Diamond, R. J. Hajjar |
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| Rok vydání: | 2018 |
| Předmět: | |
| Zdroj: | Physics of Plasmas. 25:022301 |
| ISSN: | 1089-7674 1070-664X |
| DOI: | 10.1063/1.5018320 |
| Popis: | This paper describes the ecology of drift wave turbulence and mean flows in the coupled drift-ion acoustic wave plasma of a CSDX linear device. A 1D reduced model that studies the spatiotemporal evolution of plasma mean density n¯, and mean flows v¯y and v¯z, in addition to fluctuation intensity e, is presented. Here, e=〈n2+(∇⊥ϕ)2+vz2〉 is the conserved energy field. The model uses a mixing length lmix inversely proportional to both axial and azimuthal flow shear. This form of lmix closes the loop on total energy. The model self-consistently describes variations in plasma profiles, including mean flows and turbulent stresses. It investigates the energy exchange between the fluctuation intensity and mean profiles via particle flux 〈nvx〉 and Reynolds stresses 〈vxvy〉 and 〈vxvz〉. Acoustic coupling breaks parallel symmetry and generates a parallel residual stress Πxzres. The model uses a set of equations to explain the acceleration of v¯y and v¯z via Πxyres∝∇n¯ and Πxyres∝∇n¯. Flow dynamics in the para... |
| Databáze: | OpenAIRE |
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