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This note compares the electrical energy requirements of accelerator (ATW) and fusion plants designed to transmute nuclides of fission wastes. Both systems use the same blanket concept but for each source neutron the fusion system...
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This note compares the electrical energy requirements of accelerator (ATW) and fusion plants designed to transmute nuclides of fission wastes. Both systems use the same blanket concept but for each source neutron the fusion system must utilize one blanket neutron for tritium breeding. The ATW and fusion plants are found to have the same electrical energy requirement per available blanket neutron when the blanket coverage is comparable and fusion Q (approx) 1, but the fusion plant has only a fraction of the energy requirement when Q (much(underscore)gt) 1. If the blanket thermal energy is converted to electricity, the fusion plant and ATW have comparable net electrical energy outputs per available neutron when Q (>=) 2.
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Through semi-independent absolute calibrations of multiply redundant neutron detector systems, the Tokamak Fusion Test Reactor (TFIR) has achieved (+-)7% (one-sigma) accuracy in its fusion power measurements. This has required car...
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Through semi-independent absolute calibrations of multiply redundant neutron detector systems, the Tokamak Fusion Test Reactor (TFIR) has achieved (+-)7% (one-sigma) accuracy in its fusion power measurements. This has required careful attention to the linearity of detectors up to the present highest fusion power levels achieved on TFTR of over 10 MW. The extended duration of the DT program on TFTR has also tested the stability of the detector systems. These issues of calibration, linearity, and stability are reviewed for the TFTR experience and how it can be applied to plans for ITER.
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Increasing the amount of lithium pellet injection during the supershot conditioning procedures has enabled reliable enhancement of supershot confinement at higher plasma currents. Some shots have exceptionally good performance, wi...
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Increasing the amount of lithium pellet injection during the supershot conditioning procedures has enabled reliable enhancement of supershot confinement at higher plasma currents. Some shots have exceptionally good performance, with peak global parameters up to (sup (tau))E=205 ms, S(sub n)=5.6 (times) 10(sup 16)n/s and Q(sub DD)=2. 1 (times) 10(sup (minus)3).
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摘要 :
Increasing the amount of lithium pellet injection during the supershot conditioning procedures has enabled reliable enhancement of supershot confinement at higher plasma currents. Some shots have exceptionally good performance, wi...
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Increasing the amount of lithium pellet injection during the supershot conditioning procedures has enabled reliable enhancement of supershot confinement at higher plasma currents. Some shots have exceptionally good performance, with peak global parameters up to (sup (tau))E=205 ms, S(sub n)=5.6 (times) 10(sup 16)n/s and Q(sub DD)=2. 1 (times) 10(sup (minus)3).
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The measured burnup fraction of the 1-MeV tritons produced in a deuterium tokamak plasma, multiplied by 17.5, is essentially the small-signal fusion energy gain g/sub T/ for an ideal 1-MeV triton beam injected into the deuterium p...
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The measured burnup fraction of the 1-MeV tritons produced in a deuterium tokamak plasma, multiplied by 17.5, is essentially the small-signal fusion energy gain g/sub T/ for an ideal 1-MeV triton beam injected into the deuterium plasma. The measured g/sub T/ can be converted directly into the two-component fusion energy gain that would be realized if a lower energy tritium beam were injected into the plasma, or if a deuterium beam were injected into a tritium target plasma having the same parameters as the acutal deuterium plasma. Under certain conditions, g/sub T/ greater than or equal to 1 can be obtained by injection of a low-current 225-keV tritium beam into a hot deuterium plasma, thereby verifying that the plasma has the essential characteristics needed for achieving macroscopic fusion energy ''break-even.''. (ERA citation 12:010579)
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The minimum fusion-neutron flux needed to observe nuclear-pumped lasing with tokamaks can be reduced substantially by optimizing neutron scattering into the laser cell, located between adjacent toroidal-field coils. The laser line...
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The minimum fusion-neutron flux needed to observe nuclear-pumped lasing with tokamaks can be reduced substantially by optimizing neutron scattering into the laser cell, located between adjacent toroidal-field coils. The laser lines most readily pumped are probably the sup 3 He-Ne lines at 0.633 mu and in the infrared, where the sup 3 He-Ne gas is excited by energetic ions produced in the sup 3 He(n,p)T reaction. These lines are expected to lase at the levels of D-T neutron flux foreseen for the TFTR in 1989 (>>10 sup 12 n/cm sup 2 /s), while amplification should be observable at the existing levels of D-D neutron flux (greater than or equal to 5 x 10 sup 9 n/cm sup 2 /s). Lasing on the 1.73 mu and 2.63 mu transitions of Xe may be observable at the maximum expected levels of D-T neutron flux in TFTR enhanced by scattering. (ERA citation 12:001092)
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We report measurements of the fusion reaction rate in the Tokamak Fusion Test Reactor (TFTR) covering a wide range of plasma conditions and injected neutral beam powers up to 6.3 MW. The fusion-neutron production rate in beam-inje...
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We report measurements of the fusion reaction rate in the Tokamak Fusion Test Reactor (TFTR) covering a wide range of plasma conditions and injected neutral beam powers up to 6.3 MW. The fusion-neutron production rate in beam-injected plasmas decreases slightly with increasing plasma density n/sub e/, even though the energy confinement parameter n/sub e/tau/sub E/ generally increases with density. The measurements indicate and Fokker-Planck simulations show that with increasing density the source of fusion neutrons evolves from mainly beam-beam and beam-target reactions at very low n/sub e/ to a combination of beam-target and thermonuclear reactions at high n/sub e/. At a given plasma current, the reduction in neutron source strength at higher n/sub e/ is due to both a decrease in electron temperature and in beam-beam reaction rate. The Fokker-Planck simulations also show that at low n/sub e/, plasma rotation can appreciably reduce the beam-target reaction rate for experiments with co-injection only. The variation of neutron source strength with plasma and beam parameters is as expected for beam-dominated regimes. However, the Fokker-Planck simulations systematically overestimate the measured source strength by a factor of 2 to 3; the source of this discrepancy has not yet been identified. (ERA citation 11:006723)
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sup 3 He placed in an annular cell around a tokamak fusion generator can convert moderated fusion neutrons to energetic ions by the sup 3 He(n,p)T reaction, and thereby excite gaseous lasants mixed with the sup 3 He while simultan...
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sup 3 He placed in an annular cell around a tokamak fusion generator can convert moderated fusion neutrons to energetic ions by the sup 3 He(n,p)T reaction, and thereby excite gaseous lasants mixed with the sup 3 He while simultaneously breeding tritium. The total sup 3 He inventory is about 4 kg for large tokamak devices. Special configurations of toroidal-field magnets, neutron moderators and beryllium reflectors are required to permit nearly uniform neutron current into the laser cell with minimal attenuation. The annular laser radiation can be combined into a single output beam at the top of the tokamak. (ERA citation 12:001093)
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The TFTR Lithium Blanket Module is an assembly containing 650 kg of lithium oxide that will be used to test the ability of neutronics codes to model the tritium breeding characteristics of limited-coverage breeding zones in a toka...
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The TFTR Lithium Blanket Module is an assembly containing 650 kg of lithium oxide that will be used to test the ability of neutronics codes to model the tritium breeding characteristics of limited-coverage breeding zones in a tokamak. It is required that tritium concentrations as low as 0.1 nCi/g bred in both metallic lithium samples and lithium oxide pellets be measured with an uncertainty not exceeding +- 6%. A tritium assay technique for the metallic samples which meets this criterion has been developed. Two assay techniques for the lithium oxide pellets are being investigated. In one, the pellets are heated in a flowing stream of hydrogen, while in the other, the pellets are dissolved in 12 M hydrochloric acid. (ERA citation 09:013039)
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Progress is reported on the following studies: thermal neutron absorption cross section of sulfur and the exp 252 Cf nu bar dilemma, the sigma (H)/sigma (Mn) cross section ratio, the sigma (H)/sigma (B) cross section ratio, 14 MeV...
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Progress is reported on the following studies: thermal neutron absorption cross section of sulfur and the exp 252 Cf nu bar dilemma, the sigma (H)/sigma (Mn) cross section ratio, the sigma (H)/sigma (B) cross section ratio, 14 MeV neutron cross section measurements, beryllium-based pulsed neutron detector, and testing charged particle transport and Monte Carlo codes. (ERA citation 10:024744)
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