An Implicit Monte Carlo Method for Simulation of Impurity Transport in Divertor Plasma

✍ Scribed by Akiko Suzuki; Tomonori Takizuka; Katsuhiro Shimizu; Nobuhiko Hayashi; Akiyoshi Hatayama; Masatada Ogasawara

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 311 KB
• Volume: 131
• Category: Article
• ISSN: 0021-9991
• DOI: 10.1006/jcph.1996.5600

✦ Synopsis

parameters. The minimum time among those is generally smaller than the other characteristic times of impurity be-A new ''implicit'' Monte Carlo (IMC) method has been developed to simulate ionization and recombination processes of impurity ions havior. Thus the characteristic times of ionization and rein divertor plasmas. The IMC method takes into account many ioncombination are the dominant factors to choose the time ization and recombination processes during a time step ⌬t. The step in a conventional Monte Carlo calculation. As a result, time step is not limited by a condition, ⌬t Ӷ min ( min ; the minimum long computation time is required for the impurity transcharacteristic time of atomic processes), which is forced to be port simulation with the simple hit-or-miss method.

adopted in conventional Monte Carlo methods. We incorporate this method into a one-dimensional impurity transport model. In this

In order to reduce the computation time, a new Monte transport calculation, impurity ions are followed with the time step Carlo method that is free from the condition of ⌬t Ӷ i/r about 10 times larger than that used in conventional methods. The is required to be developed. Previously, an implicit Monte average charge state of impurities, ͗Z ͘, and the radiative cooling Carlo method was developed by Fleck and Cummings [6] rate, L(T e ), are calculated at the electron temperature T e in divertor and by Fleck and Canfield [7] for the nonlinear radiation plasmas. These results are compared with thosed obtained from the simple noncoronal model. ᮊ 1997 Academic Press transport. The radiation field and the material energy density are calculated in a self-consistent manner analogous to the implicit finite difference solution of coupled matter 193