### Abstract

A hybrid model of diffusion and first flight collision probability (FFCP) for two-dimensional (2-D) neutral transport has been developed to analyze neutral behavior in linear gas divertors. In the model, the axial transport of the neutrals is described by the diffusion approximation, while the FFCP model is applied to the radial neutral transport. The model is applied to the analysis of PISCES-A experiments for the model validation. Calculated density profiles of atomic and molecular hydrogen are qualitatively in good agreement with the experimental results. The molecular density sharply decreases near the ionization region where the electron density profile has the maximum. This sharp decrease in the molecular density leads to the atomic density peak. In addition, a sensitivity study of the wall reflection condition suggests that the wall recombination of atoms and the reemission as molecules are important processes to interpret the experimental results.

Original language | English |
---|---|

Pages (from-to) | 368-379 |

Number of pages | 12 |

Journal | Journal of Nuclear Science and Technology |

Volume | 37 |

Issue number | 4 |

Publication status | Published - 2000 Apr |

### Fingerprint

### Keywords

- Atomic density
- Diffusion approximation
- Divertor
- First flight collision probability
- Gas divertor
- Linear plasma devices
- Molecular density
- Neutral transport
- Nuclear fusion

### ASJC Scopus subject areas

- Nuclear Energy and Engineering

### Cite this

*Journal of Nuclear Science and Technology*,

*37*(4), 368-379.

**Modeling of Neutral Transport in Linear Divertor Plasma Using First Flight Collision Probability Method.** / Hatayama, Akiyoshi; Fukai, Yuzo; Kawakami, Yoshiyuki; Yamada, Kazuhiro.

Research output: Contribution to journal › Article

*Journal of Nuclear Science and Technology*, vol. 37, no. 4, pp. 368-379.

}

TY - JOUR

T1 - Modeling of Neutral Transport in Linear Divertor Plasma Using First Flight Collision Probability Method

AU - Hatayama, Akiyoshi

AU - Fukai, Yuzo

AU - Kawakami, Yoshiyuki

AU - Yamada, Kazuhiro

PY - 2000/4

Y1 - 2000/4

N2 - A hybrid model of diffusion and first flight collision probability (FFCP) for two-dimensional (2-D) neutral transport has been developed to analyze neutral behavior in linear gas divertors. In the model, the axial transport of the neutrals is described by the diffusion approximation, while the FFCP model is applied to the radial neutral transport. The model is applied to the analysis of PISCES-A experiments for the model validation. Calculated density profiles of atomic and molecular hydrogen are qualitatively in good agreement with the experimental results. The molecular density sharply decreases near the ionization region where the electron density profile has the maximum. This sharp decrease in the molecular density leads to the atomic density peak. In addition, a sensitivity study of the wall reflection condition suggests that the wall recombination of atoms and the reemission as molecules are important processes to interpret the experimental results.

AB - A hybrid model of diffusion and first flight collision probability (FFCP) for two-dimensional (2-D) neutral transport has been developed to analyze neutral behavior in linear gas divertors. In the model, the axial transport of the neutrals is described by the diffusion approximation, while the FFCP model is applied to the radial neutral transport. The model is applied to the analysis of PISCES-A experiments for the model validation. Calculated density profiles of atomic and molecular hydrogen are qualitatively in good agreement with the experimental results. The molecular density sharply decreases near the ionization region where the electron density profile has the maximum. This sharp decrease in the molecular density leads to the atomic density peak. In addition, a sensitivity study of the wall reflection condition suggests that the wall recombination of atoms and the reemission as molecules are important processes to interpret the experimental results.

KW - Atomic density

KW - Diffusion approximation

KW - Divertor

KW - First flight collision probability

KW - Gas divertor

KW - Linear plasma devices

KW - Molecular density

KW - Neutral transport

KW - Nuclear fusion

UR - http://www.scopus.com/inward/record.url?scp=0347946670&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0347946670&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0347946670

VL - 37

SP - 368

EP - 379

JO - Journal of Nuclear Science and Technology

JF - Journal of Nuclear Science and Technology

SN - 0022-3131

IS - 4

ER -