Simple Core‐SOL‐Divertor Model To Investigate Plasma Operational Space

Abstract

We develop a simple Core‐SOL‐Divertor (C‐S‐D) model to investigate the core and edge operational space. To construct the integrated C‐S‐D model, 0D core plasma model of ITER physics guidelines and two‐point SOLdivertor model are applied. To get the reasonable boundary condition at the core‐edge interface, we investigate the particle balance for the divertor, SOL, and core plasma region, respectively. Moreover, we apply the C‐S‐D model to LH transition phase of ITER and compare with the scaling model, which consists of the two‐point model and the SOL density scaling law. According to the above comparison, we find that the particle flux across the separatrix should be applied for the boundary condition in case of the transition phenomena. In addition, the oscillation of the divertor density at the LH transition is predicted. This oscillation has a possibility to have an effect on the divertor operation of ITER. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Simple Core-SOL-Divertor model and its application to operational space of HT-7U

“…S core is the core plasma surface normal to the particle flux. The ionization fraction in the divertor region, which was not included in the previous study [3], is modeled by [9] f div…”

“…The usual definitions for the global particle and power balance are applied in the present paper [3], and the particle and energy confinement times are required to solve 0D plasma transport model. The scaling law of the L-mode energy confinement time s ITER89L E [4] is applied to the energy confinement time…”

“…Based on the particle and power balance of the core plasma [3,4], the total particle flux U p and the total heat flux Q in across the separatrix are U p = (n 20 V p )/(C p s E ) and Q in = (0.048n 20 TV p )/s E , respectively (V p is the plasma volume). From these quantities and the definition of the energy confinement time, the temperature and the density of the core plasma are written as T = C T Q in /U p and n 20 ¼ C n U 10=9 p =Q 5=9 in , respectively (where C T and C n are functions of core plasma parameters).…”

“…The basic concept of the C-S-D model was presented in Ref. [3]. In the present paper, we improve the C-S-D model and apply it to investigate the plasma operational space of low hybrid current drive (LHCD) experiments for HT-7U.…”

Effect of SOL Decay Length on Modeling of Divertor Detachment by Using Simple Core‐SOL‐Divertor Model

“…We apply the 0D plasma model based on ITER physics guidelines to the core plasma transport. The usual definitions for the global particle and power balance are applied in the present paper [4], and the particle and energy confinement times are required to solve 0D plasma transport model.…”