Far scrape-off layer and near wall plasma studies in DIII-D

Ga–a26119 Measurements and Simulations of Scrape-off Layer Flows in the Diii-d Tokamak

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Modeling of supersonic plasma flow in the scrape-off layer

The substantial drop of the plasma temperature along magnetic field lines with increasing plasma density is one of the main features in tokamak divertors. As a result the temperature gradient at the divertor plates becomes very steep and the boundary condition normally applied for the parallel Mach number M at the target, Mt = 1, cannot be satisfied. In this case the value of Mt based on the ge...

Plasma shaping effects on tokamak scrape-off layer turbulence

The impact of plasma shaping on tokamak scrape-off layer (SOL) turbulence is investigated. The drift-reduced Braginskii equations are written for arbitrary magnetic geometries, and an analytical equilibrium model is used to introduce the dependence of turbulence equations on tokamak inverse aspect ratio ( ), Shafranov’s shift (∆), elongation (κ), and triangularity (δ). A linear study of plasma ...

Stochastic modeling of intermittent scrape-off layer plasma fluctuations.

Single-point measurements of fluctuations in the scrape-off layer of magnetized plasmas are generally found to be dominated by large-amplitude bursts which are associated with radial motion of bloblike structures. A stochastic model for these fluctuations is presented, with the plasma density given by a random sequence of bursts with a fixed wave form. When the burst events occur in accordance ...

Aspect ratio effects on limited scrape-off layer plasma turbulence