Self-consistent cross-field transport model for core and edge plasma transport

The 2D mean-field plasma edge transport description of plasma wall interaction is completed by a κ-e model as in Reynolds Average Navier Stokes simulations for neutral fluids. The local evolution of the turbulent kinetic energy κ and its dissipation rate e are revisited and slightly modified. It is shown that the κ-e extends the quasilinear approach by self-consistently determining κ and the relevant time κ/e leading to the diffusion coefficient κ 2 /e. The κ-e evolution is also shown to be equivalent to both coupled Ginzburg-Landau amplitude equations and predator-prey systems where κ is the prey and e the predator. The dissipation process e we enforce describes the small scale dissipation of Kolmogorov cascades. It depends on a free parameter akin to a velocity V. The chosen closure relates V to the the parallel connection time and the normalized Scrape-Off layer width qρ * , q is the safety factor and ρ * the ratio of the characteristic Larmor radius and plasma minor radius. A 1D model with κ-e self-organized transport is used for comparison to empirical scaling laws of SOL width and energy confinement time in L-mode plasmas. Shortfalls of the scaling laws are analyzed. Possible changes of the closure for V are discussed. The 1D model is also used to test the transport response to a dependence of V to large scale velocity shear. Spontaneous confinement improvement when increasing the heating power