Plasma Characteristics and Gas Transport in the Single-Null Poloidal Divertor of the International Tokamak Reactor

Modeling of supersonic plasma flow in the scrape-off layer

“…30 is the effective energy loss of electrons due to excitation and ionization of neutral atoms [17]. Ionization, radiative and three-body recombination rate coefficients are based on the Refs.…”

Numerical Simulation of Hydrogenic Atomic Losses in a Divertor Plasma

“…Reference values for the perpendicular transport coefficients are: x, = x, = 1.0 m3-I and D, = 0.3 m 2 r 1 . The avearge energy loss {, in eV per hydrogen ionisation event is [4]: <, = 17.5 + (5 + 3747;) logl,(lOzi/n,) with n, in rn-' and T, in e l ' . The neutrals are treated with a Monte Carlo code (a simplified version of NIMBUS).…”

Multiplicative Classification of Associative Rings

“…In these equations, L| is the length of the field line (L| = 7rRo/m + £ d and L| = 7rRoq/m + £ d /sin<£ in the poloidal and toroidal configurations, respectively; for limiter discharges, £ d need not be added), xi is the coefficient of longitudinal heat conductivity (we assume the classical Spitzer coefficient xi = 2 x 10 20 T s 5/2 ), X, = 2 X 10 12 T 2 /n s is the path length of the electrons, the coefficient a (the flux limit factor [20], a ~ 3-10) describes the drop in heat flux for X|/L| > 1, T d is the plasma temperature at the divertor plates, 0 ~ 1.6 is a coefficient to allow for the distortion of the distribution function near the plates [17,21], S s = 27rRo27rak is the area of the magnetic surface bounded by the separatrix, Xx = 7D Bohm , 7 is a coefficient of ~3 -8 , Wj is the fraction of energy lost through ionization in the divertor channel and W ;i is the fraction of energy lost through ionization at the plates. W takes into account both losses through ionization of the main gas, which for hydrogen and deuterium can be estimated by the formula (see Ref.…”