Study of the impact of pre- and real-time deposition of lithium on plasma performance on NSTX

Canal, G P; Maingi, R; Evans, T E; Kaye, S M; Mansfield, D K

doi:10.11578/1562025

Title: Study of the impact of pre- and real-time deposition of lithium on plasma performance on NSTX

Dataset
Other Related Research

Abstract

The efficiency of two lithium (Li) injection methods used on the National Spherical Torus Experiment (NSTX) are compared in terms of the amount of Li used to produce equivalent plasma performance improvements, namely Li evaporation over the divertor plates, prior to the initiation of the discharge, and real-time Li injection directly into the plasma scrape-off layer during the discharge. The measurements show that the real-time method can affect the energy confinement and edge stability of NSTX plasmas in a more efficient way than the Li evaporation method as it requires only a fraction of the amount of Li used by the evaporation method to produce similar improvements.

Authors:: Canal, G P; Maingi, R; Evans, T E; Kaye, S M; Mansfield, D K

Publication Date:: Tue Jan 01 00:00:00 EST 2019

DOE Contract Number:: AC02-09CH11466

Research Org.:: Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Sponsoring Org.:: U. S. Department of Energy

Keywords:: Tokamak; Plasma; NSTX; Lithium; Performance; Stability;

OSTI Identifier:: 1562025

DOI:: https://doi.org/10.11578/1562025

Citation Formats


                    Canal, G P, Maingi, R, Evans, T E, Kaye, S M, and Mansfield, D K. Study of the impact of pre- and real-time deposition of lithium on plasma performance on NSTX.  United States: N. p., 2019. 
        Web.  doi:10.11578/1562025.

Copy to clipboard


                    Canal, G P, Maingi, R, Evans, T E, Kaye, S M, & Mansfield, D K. Study of the impact of pre- and real-time deposition of lithium on plasma performance on NSTX.  United States.  doi:https://doi.org/10.11578/1562025

Copy to clipboard


                    Canal, G P, Maingi, R, Evans, T E, Kaye, S M, and Mansfield, D K. 2019.  
"Study of the impact of pre- and real-time deposition of lithium on plasma performance on NSTX".  United States.  doi:https://doi.org/10.11578/1562025.  https://www.osti.gov/servlets/purl/1562025. Pub date:Tue Jan 01 00:00:00 EST 2019

Copy to clipboard


                    
@article{osti_1562025,

  title        = {Study of the impact of pre- and real-time deposition of lithium on plasma performance on NSTX},

  author       = {Canal, G P and Maingi, R and Evans, T E and Kaye, S M and Mansfield, D K},

  abstractNote = {The efficiency of two lithium (Li) injection methods used on the National Spherical Torus Experiment (NSTX) are compared in terms of the amount of Li used to produce equivalent plasma performance improvements, namely Li evaporation over the divertor plates, prior to the initiation of the discharge, and real-time Li injection directly into the plasma scrape-off layer during the discharge. The measurements show that the real-time method can affect the energy confinement and edge stability of NSTX plasmas in a more efficient way than the Li evaporation method as it requires only a fraction of the amount of Li used by the evaporation method to produce similar improvements.},

  doi          = {10.11578/1562025},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Tue Jan 01 00:00:00 EST 2019},

  month        = {Tue Jan 01 00:00:00 EST 2019}

}

Copy to clipboard

Dataset:

View Dataset

DOI: https://doi.org/10.11578/1562025

Save / Share:

Export Metadata

Save to My Library

Similar records in DOE Data Explorer and OSTI.GOV collections:

Plasma boundary shape control and real-time equilibrium reconstruction on NSTX-U

Dataset Boyer, M ; Battaglia, D ; Mueller, D ; ...

The upgrade to the National Spherical Torus eXperiment (NSTX-U) included two main improvements: a larger center-stack, enabling higher toroidal field and longer pulse duration, and the addition of three new tangentially aimed neutral beam sources, which increase available heating and current drive, and allow for flexibility in shaping power, torque, current, and particle deposition profiles. To best use these new capabilities and meet the high-performance operational goals of NSTX-U, major upgrades to the NSTX-U Control System (NCS) hardware and software have been made. Several control algorithms, including those used for real-time equilibrium reconstruction and shape control, have been upgraded tomore »« less
A scalable real-time framework for Thomson scattering analysis: Application to NSTX-U

Dataset F. M. Laggner, A. Diallo, B. P. LeBlanc, R. Rozenblat, G. Tchilinguirian, E.Kolemen, the NSTX-U team

A detailed description of a prototype setup for real-time (rt) Thomson scattering (TS) analysis is presented and implemented in the multi-point Thomson scattering (MPTS) diagnostic system at the National Spherical Torus Experiment Upgrade(NSTX-U). The data acquisition hardware was upgraded with rt capable electronics (rt-analog digital converters (ADCs) and a rt server) that allow for fast digitization of the laser pulse signal of eight radial MPTS channels. In addition, a new TS spectrum analysis software for a rapid calculation of electron temperature (Te) and electron density (ne) was developed. Testing of the rt hardware and data analysis soft-ware was successfully completedmore »« less
Real-time Radiative Divertor Feedback Control Development for the NSTX-U Tokamak using a Vacuum Ultraviolet Spectrometer

Dataset Soukhanovskii, V.A. ; Kaita, R. ; Stratton, B.

A radiative divertor technique is planned for the NSTX-U tokamak to prevent excessive erosion and thermal damage of divertor plasma-facing components in H-mode plasma discharges with auxiliary heating up to 12 MW. In the radiative (partially detached) divertor, extrinsically seeded deuterium or impurity gases are used to increase plasma volumetric power and momentum losses. A real-time feedback control of the gas seeding rate is planned for discharges of up to 5 s duration. The outer divertor leg plasma electron temperature Te estimated spectroscopically in real time will be used as a control parameter. A vacuum ultraviolet spectrometer McPherson Model 251more »« less
Initial operation of the NSTX-Upgrade real-time velocity diagnostic

Dataset Podesta, M. ; Bell, R.E.

A real-time velocity (RTV) diagnostic based on active charge-exchange recombination spectroscopy is now operational on the National Spherical Torus Experiment-Upgrade (NSTX-U) spherical torus (Menard et al 2012 Nucl. Fusion 52 083015). The system has been designed to supply plasma velocity data in real time to the NSTX-U plasma control system, as required for the implementation of toroidal rotation control. Measurements are available from four radii at a maximum sampling frequency of 5 kHz. Post-discharge analysis of RTV data provides additional information on ion temperature, toroidal velocity and density of carbon impurities. Examples of physics studies enabled by RTV measurements frommore »« less
Real-time capable modeling of neutral beam injection on NSTX-U using neural networks

Dataset Boyer, M D ; Kaye, S ; Erickson, K

A new model of heating, current drive, torque and other effects of neutral beam injection on NSTX-U that uses neural networks has been developed. The model has been trained and tested on the results of the Monte Carlo code NUBEAM for the database of experimental discharges taken during the first operational campaign of NSTX-U. By projecting flux surface quantities onto empirically derived basis functions, the model is able to efficiently and accurately reproduce the behavior of both scalars, like the total neutron rate and shine through, and profiles, like beam current drive and heating. The model has been tested onmore »« less

Similar Records