Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Measurements of gas utilization in a test TFTR neutral beam injector have been performed to study the feasibility of running tritium neutral beams with existing ion sources. Gas consumption is limited by the restriction of 50,000 curies of T2 allowed on site. It was found that the gas efficiency of the present long-pulse ion sources is higher than it was with previous short-pulse sources. Gas efficiencies were studied over the range of 35 to 55%. At the high end of this range the neutral fraction of the beam fell below that predicted by room temperature molecular gas flow. This is consistent with observations made on the JET injectors, where it has been attributed to beam heating of the neutralizer gas and a concomitant increase in conductance. It was found that a working gas isotope exchange from H2 to D2 could be accomplished on the first beam shot after changing the gas supply, without any intermediate preconditioning. The mechanism believed responsible for this phenomenon is heating of the plasma generator walls by the arc and a resulting thermal desorption of all previously adsorbed and implanted gas. Finally, it was observed that an ion source conditioned to 120 kV operation could produce a beam pulse after a waiting period of fourteen hours by preceding the beam extraction with several hi-pot/filament warm-up pulses, without any gas consumption. 18 refs., 7 figs., 2 tabs.
Gas Utilization in TFTR (Tokamak Fusion Test Reactor) Neutral Beam Injectors
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Measurements of gas utilization in a test TFTR neutral beam injector have been performed to study the feasibility of running tritium neutral beams with existing ion sources. Gas consumption is limited by the restriction of 50,000 curies of T2 allowed on site. It was found that the gas efficiency of the present long-pulse ion sources is higher than it was with previous short-pulse sources. Gas efficiencies were studied over the range of 35 to 55%. At the high end of this range the neutral fraction of the beam fell below that predicted by room temperature molecular gas flow. This is consistent with observations made on the JET injectors, where it has been attributed to beam heating of the neutralizer gas and a concomitant increase in conductance. It was found that a working gas isotope exchange from H2 to D2 could be accomplished on the first beam shot after changing the gas supply, without any intermediate preconditioning. The mechanism believed responsible for this phenomenon is heating of the plasma generator walls by the arc and a resulting thermal desorption of all previously adsorbed and implanted gas. Finally, it was observed that an ion source conditioned to 120 kV operation could produce a beam pulse after a waiting period of fourteen hours by preceding the beam extraction with several hi-pot/filament warm-up pulses, without any gas consumption. 18 refs., 7 figs., 2 tabs.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Measurements of gas utilization in a test TFTR neutral beam injector have been performed to study the feasibility of running tritium neutral beams with existing ion sources. Gas consumption is limited by the restriction of 50,000 curies of T2 allowed on site. It was found that the gas efficiency of the present long-pulse ion sources is higher than it was with previous short-pulse sources. Gas efficiencies were studied over the range of 35 to 55%. At the high end of this range the neutral fraction of the beam fell below that predicted by room temperature molecular gas flow. This is consistent with observations made on the JET injectors, where it has been attributed to beam heating of the neutralizer gas and a concomitant increase in conductance. It was found that a working gas isotope exchange from H2 to D2 could be accomplished on the first beam shot after changing the gas supply, without any intermediate preconditioning. The mechanism believed responsible for this phenomenon is heating of the plasma generator walls by the arc and a resulting thermal desorption of all previously adsorbed and implanted gas. Finally, it was observed that an ion source conditioned to 120 kV operation could produce a beam pulse after a waiting period of fourteen hours by preceding the beam extraction with several hi-pot/filament warm-up pulses, without any gas consumption. 18 refs., 7 figs., 2 tabs.
Energy Research Abstracts
Energy Research Abstracts
Charge-exchange and Fusion Reaction Measurements During Compression Experiments with Neutral Beam Heating in the Tokamak Fusion Test Reactor
ERDA Energy Research Abstracts
Neutral Beam Injection System for the Tokamak Fusion Test Reactor
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The Tokamak Fusion Test Reactor will be installed at the Princeton Plasma Physics Laboratory facility. This is a major step to reach the goal of fusion power using toroidal magnetic fields for plasma confinement. A major part of this test reactor will be four neutral beam injection systems. These systems will inject 20 MW of 120 kV neutral deuterium atoms into the plasma for 0.5 seconds. In order to achieve the required power input to the plasma, several systems are required within the neutral beam line. These are the source, neutralizer, ion deflection magnet, calorimeter and retraction system, ion dump, cryopumps and vacuum enclosure. All of these systems have constraints imposed which increase the complexity of their designs. Since all systems must operate in a tritium environment, remote handling capabilities must be incorporated into the design. An overview is presented of the Lawrence Livermore Laboratory/Lawrence Berkeley Laboratory Neutral Beam Injection System design. Specifications for the machine and a general description of the total system are presented.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The Tokamak Fusion Test Reactor will be installed at the Princeton Plasma Physics Laboratory facility. This is a major step to reach the goal of fusion power using toroidal magnetic fields for plasma confinement. A major part of this test reactor will be four neutral beam injection systems. These systems will inject 20 MW of 120 kV neutral deuterium atoms into the plasma for 0.5 seconds. In order to achieve the required power input to the plasma, several systems are required within the neutral beam line. These are the source, neutralizer, ion deflection magnet, calorimeter and retraction system, ion dump, cryopumps and vacuum enclosure. All of these systems have constraints imposed which increase the complexity of their designs. Since all systems must operate in a tritium environment, remote handling capabilities must be incorporated into the design. An overview is presented of the Lawrence Livermore Laboratory/Lawrence Berkeley Laboratory Neutral Beam Injection System design. Specifications for the machine and a general description of the total system are presented.
Scientific and Technical Aerospace Reports
Fusion Energy Update
ERDA Energy Research Abstracts
Author: United States. Energy Research and Development Administration
Publisher:
ISBN:
Category : Medicine
Languages : en
Pages : 800
Book Description
Publisher:
ISBN:
Category : Medicine
Languages : en
Pages : 800
Book Description