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Title: Coupled plasma-neutral transport model for the scrape-off region

Abstract

Analysis of the scrape-off region requires treatment of the plasma transport along and across the field lines and inclusion of the neutral transport effects. A method for modeling the scrape-off region that is presented here uses separate models for each of these aspects that are coupled together through an iteration procedure that requires only minimal numerical effort. The method is applied here to estimate the neutral pumping rates in the pump-limiter and divertor options for a proposed deuterium-tritium (D-T) ignition experiment. High neutral recycling in the vicinity of the neutralizer plate dramatically affects pumping rates for both the pump-limiter and divertor. In both cases, the plasma flow into the channel surrounding the neutralizer plate is greatly reduced by the neutral recycling. The fraction of this flow that is pumped can be large (> 50%), but in general it is dependent on the particular geometry and plasma conditions. It is estimated that pumping speeds approximately greater than 10/sup 5/ L/s are adequate for the exhaust requirements in the pump-limiter and the divertor cases. Also, high neutral recycling on the front surface of the limiter tends to increase the neutral pumping rate.

Authors:
; ;
Publication Date:
Research Org.:
Oak Ridge National Lab., TN (USA)
OSTI Identifier:
6085181
Report Number(s):
ORNL/FEDC-84/6
ON: DE85007559
DOE Contract Number:
AC05-84OR21400
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; LIMITERS; PLASMA SCRAPE-OFF LAYER; TOKAMAK TYPE REACTORS; DIVERTORS; PLASMA DRIFT; RECYCLING; BOUNDARY LAYERS; LAYERS; THERMONUCLEAR REACTORS; 700105* - Fusion Energy- Plasma Research- Plasma Kinetics-Theoretical- (-1987)

Citation Formats

Galambos, J.D., Peng, Y.K.M., and Heifetz, D.. Coupled plasma-neutral transport model for the scrape-off region. United States: N. p., 1985. Web. doi:10.2172/6085181.
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Galambos, J.D., Peng, Y.K.M., & Heifetz, D.. Coupled plasma-neutral transport model for the scrape-off region. United States. doi:10.2172/6085181.
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Galambos, J.D., Peng, Y.K.M., and Heifetz, D.. Fri . "Coupled plasma-neutral transport model for the scrape-off region". United States. doi:10.2172/6085181. https://www.osti.gov/servlets/purl/6085181.
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@article{osti_6085181,
title = {Coupled plasma-neutral transport model for the scrape-off region},
author = {Galambos, J.D. and Peng, Y.K.M. and Heifetz, D.},
abstractNote = {Analysis of the scrape-off region requires treatment of the plasma transport along and across the field lines and inclusion of the neutral transport effects. A method for modeling the scrape-off region that is presented here uses separate models for each of these aspects that are coupled together through an iteration procedure that requires only minimal numerical effort. The method is applied here to estimate the neutral pumping rates in the pump-limiter and divertor options for a proposed deuterium-tritium (D-T) ignition experiment. High neutral recycling in the vicinity of the neutralizer plate dramatically affects pumping rates for both the pump-limiter and divertor. In both cases, the plasma flow into the channel surrounding the neutralizer plate is greatly reduced by the neutral recycling. The fraction of this flow that is pumped can be large (> 50%), but in general it is dependent on the particular geometry and plasma conditions. It is estimated that pumping speeds approximately greater than 10/sup 5/ L/s are adequate for the exhaust requirements in the pump-limiter and the divertor cases. Also, high neutral recycling on the front surface of the limiter tends to increase the neutral pumping rate.},
doi = {10.2172/6085181},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Mar 01 00:00:00 EST 1985},
month = {Fri Mar 01 00:00:00 EST 1985}
}
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Technical Report:
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DOI:  10.2172/6085181
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