Author: J. R. Wilson
Publisher:
ISBN:
Category : Tokamaks
Languages : en
Pages : 6
Book Description
High Harmonic Fast Wave Heating Experiments on NSTX.
Author: J. R. Wilson
Publisher:
ISBN:
Category : Tokamaks
Languages : en
Pages : 6
Book Description
Publisher:
ISBN:
Category : Tokamaks
Languages : en
Pages : 6
Book Description
Results of High Harmonic Fast Wave Heating Experiments on NSTX.
Author: J. Hosea
Publisher:
ISBN:
Category : National Spherical Torus Experiment (Project)
Languages : en
Pages : 4
Book Description
Publisher:
ISBN:
Category : National Spherical Torus Experiment (Project)
Languages : en
Pages : 4
Book Description
Results of High Harmonic Fast Wave Heating Experiments on NSTX.
Author: J. Hosea
Publisher:
ISBN:
Category : National Spherical Torus Experiment (Project).
Languages : en
Pages : 4
Book Description
Publisher:
ISBN:
Category : National Spherical Torus Experiment (Project).
Languages : en
Pages : 4
Book Description
High Harmonic Fast Wave Heating Experiments on NSTX.
Author: J. R. Wilson
Publisher:
ISBN:
Category : Tokamaks
Languages : en
Pages : 6
Book Description
Publisher:
ISBN:
Category : Tokamaks
Languages : en
Pages : 6
Book Description
Profile Modifications Resulting from Early High-harmonic Fast Wave Heating in NSTX.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Experiments have been performed in the National Spherical Torus Experiment (NSTX) to inject high harmonic fast wave (HHFW) power early during the plasma current ramp-up in an attempt to reduce the current penetration rate to raise the central safety factor during the flattop phase of the discharge. To date, up to 2 MW of HHFW power has been coupled to deuterium plasmas as early as t= 50 ms using the slowest interstrap phasing of k approximately equals 14 m(superscript)-1 (nf= 24). Antenna-plasma gap scans have been performed and find that for small gaps (5-8 cm), electron heating is observed with relatively small density rises and modest reductions in current penetration rate. For somewhat larger gaps (10-12 cm), weak electron heating is observed but with a spontaneous density rise at the plasma edge similar to that observed in NSTX H-modes. In the larger gap configuration, EFIT code reconstructions (without MSE[motional Stark effect]) find that resistive flux consumption is reduced as much as 30%, the internal inductance is maintained below 0.6 at 1 MA into the flattop, q(0) is increased significantly, and the MHD stability character of the discharges is strongly modified.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Experiments have been performed in the National Spherical Torus Experiment (NSTX) to inject high harmonic fast wave (HHFW) power early during the plasma current ramp-up in an attempt to reduce the current penetration rate to raise the central safety factor during the flattop phase of the discharge. To date, up to 2 MW of HHFW power has been coupled to deuterium plasmas as early as t= 50 ms using the slowest interstrap phasing of k approximately equals 14 m(superscript)-1 (nf= 24). Antenna-plasma gap scans have been performed and find that for small gaps (5-8 cm), electron heating is observed with relatively small density rises and modest reductions in current penetration rate. For somewhat larger gaps (10-12 cm), weak electron heating is observed but with a spontaneous density rise at the plasma edge similar to that observed in NSTX H-modes. In the larger gap configuration, EFIT code reconstructions (without MSE[motional Stark effect]) find that resistive flux consumption is reduced as much as 30%, the internal inductance is maintained below 0.6 at 1 MA into the flattop, q(0) is increased significantly, and the MHD stability character of the discharges is strongly modified.
High-Harmonic Fast-Wave Heating in NSTX.
Author: B. P. LeBlanc
Publisher:
ISBN:
Category :
Languages : en
Pages : 12
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 12
Book Description
High-harmonic Fast-wave Heating in NSTX.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
High-Harmonic Fast-Wave (HHFW), a radio-frequency technique scenario applicable to high-beta plasmas, has been selected as one of the main auxiliary heating systems on the National Spherical Torus Experiment (NSTX). The HHFW antenna assembly comprises 12 toroidally adjacent current elements, extending poloidally and centered on the equatorial plane. This paper reviews experimental results obtained with a symmetrical (vacuum) launching spectrum with k.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
High-Harmonic Fast-Wave (HHFW), a radio-frequency technique scenario applicable to high-beta plasmas, has been selected as one of the main auxiliary heating systems on the National Spherical Torus Experiment (NSTX). The HHFW antenna assembly comprises 12 toroidally adjacent current elements, extending poloidally and centered on the equatorial plane. This paper reviews experimental results obtained with a symmetrical (vacuum) launching spectrum with k.
Exploration of High Harmonic Fast Wave Heating on the National Spherical Torus Experiment
Author: J. R. Wilson
Publisher:
ISBN:
Category :
Languages : en
Pages : 6
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 6
Book Description
High-harmonic Fast Wave Heating Experiments in CDX-U.
Author: Jonathan Edward Menard
Publisher:
ISBN:
Category :
Languages : en
Pages : 4
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 4
Book Description
High-harmonic Fast Wave Heating Experiments in CDX-U.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 4
Book Description
One of the primary objectives of the proposed National Spherical Tokamak Experiment (NSTX) is the investigation of very high [beta] regimes. Consequently, finding efficient methods of non-inductive heating and current drive required to heat and sustain such plasmas is of considerable importance. High-frequency fast waves are a promising candidate in this regard. However, in NSTX, the field-line pitch at the outer midplane will range from 0 up to 60 degrees from plasma start-up to current flattop. Thus, antenna strap orientation with respect to the edge magnetic field may have a serious impact on power coupling and absorption. To address this issue, the vacuum vessel of the Current Drive Experiment -- Upgrade (CDX-U) spherical tokamak has been upgraded to accommodate a rotatable two-strap antenna capable of handling several hundred kilowatts in short pulses. Details of the antenna design and results from loading measurements made as a function of power, strap angle, and strap phasing will be presented. Results from microwave scattering experiments will also be discussed.
Publisher:
ISBN:
Category :
Languages : en
Pages : 4
Book Description
One of the primary objectives of the proposed National Spherical Tokamak Experiment (NSTX) is the investigation of very high [beta] regimes. Consequently, finding efficient methods of non-inductive heating and current drive required to heat and sustain such plasmas is of considerable importance. High-frequency fast waves are a promising candidate in this regard. However, in NSTX, the field-line pitch at the outer midplane will range from 0 up to 60 degrees from plasma start-up to current flattop. Thus, antenna strap orientation with respect to the edge magnetic field may have a serious impact on power coupling and absorption. To address this issue, the vacuum vessel of the Current Drive Experiment -- Upgrade (CDX-U) spherical tokamak has been upgraded to accommodate a rotatable two-strap antenna capable of handling several hundred kilowatts in short pulses. Details of the antenna design and results from loading measurements made as a function of power, strap angle, and strap phasing will be presented. Results from microwave scattering experiments will also be discussed.