Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 28
Book Description
Molybdenum Sources at the Alcator C-Mod Divertor
A Study of Molybdenum Influxes and Transport in Alcator C-Mod
Author: B. Lipschultz
Publisher:
ISBN:
Category :
Languages : en
Pages : 27
Book Description
We present a characterization of molybdenum sources, GMo, core Mo content, NMo, and their dependencies on Alcator C-Mod operational regimes. The primary impurity source locations are the divertor, the inner wall and the ICRF antenna limiters. Boronization is used to coat the first-wall surfaces with a thin layer of B which greatly reduces the Mo sources for a period of time, eroding away with an e-folding period of 15-50 discharges. The penetration of molybdenum into the core plasma under different conditions is analyzed using the concept of penetration factors, PF=NMo /GMo (seconds). In general the inner wall Mo source is large (%7E1018/sec) but is found to be relatively uncorrelated with the core Mo content in diverted plasmas. The outer divertor source is of similar order to that from the inner wall and has a penetration factor in the range 10-5 - 2x10-3 seconds depending on density and confinement mode. The antenna limiter Mo sources are typically smaller, but with higher penetration factors of 10-3 - 2x10-2 seconds. The behavior of the antenna limiter sources is consistent with physical sputtering due to the influence of RF sheath rectification. Measurements of the plasma potential on field lines connected to the antenna are very high when the antennas are energized, often reaching hundreds of volts.
Publisher:
ISBN:
Category :
Languages : en
Pages : 27
Book Description
We present a characterization of molybdenum sources, GMo, core Mo content, NMo, and their dependencies on Alcator C-Mod operational regimes. The primary impurity source locations are the divertor, the inner wall and the ICRF antenna limiters. Boronization is used to coat the first-wall surfaces with a thin layer of B which greatly reduces the Mo sources for a period of time, eroding away with an e-folding period of 15-50 discharges. The penetration of molybdenum into the core plasma under different conditions is analyzed using the concept of penetration factors, PF=NMo /GMo (seconds). In general the inner wall Mo source is large (%7E1018/sec) but is found to be relatively uncorrelated with the core Mo content in diverted plasmas. The outer divertor source is of similar order to that from the inner wall and has a penetration factor in the range 10-5 - 2x10-3 seconds depending on density and confinement mode. The antenna limiter Mo sources are typically smaller, but with higher penetration factors of 10-3 - 2x10-2 seconds. The behavior of the antenna limiter sources is consistent with physical sputtering due to the influence of RF sheath rectification. Measurements of the plasma potential on field lines connected to the antenna are very high when the antennas are energized, often reaching hundreds of volts.
Study of Molybdenum Sources and Screening in the Alcator C-Mod Tokamak
Author: Dimitrios Pappas
Publisher:
ISBN:
Category :
Languages : en
Pages : 191
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 191
Book Description
Molybdenum Sources and Transport in Alcator C-Mod
Author: B. Lipschultz
Publisher:
ISBN:
Category :
Languages : en
Pages : 10
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 10
Book Description
Molybdenum Erosion Measurements in Alcator C-Mod
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 14
Book Description
Erosion of molybdenum was measured on a set of 21 tiles after a run campaign of 1,090 shots in the Alcator C-Mod tokamak. The net erosion of molybdenum, was determined from changes in the depth of a thin chromium marker layer measured by Rutherford backscattering. Net Mo erosion was found to be approximately 150 nm near the outer divertor strike point, and much less everywhere else. Gross erosion rates by sputtering were estimated using ion energies and fluxes obtained from Langmuir probe measurements of edge-plasma conditions. Predicted net erosion using calculated gross erosion with prompt redeposition and measured net erosion agree within a factor of 3. Sputtering by boron and molybdenum impurities dominates erosion.
Publisher:
ISBN:
Category :
Languages : en
Pages : 14
Book Description
Erosion of molybdenum was measured on a set of 21 tiles after a run campaign of 1,090 shots in the Alcator C-Mod tokamak. The net erosion of molybdenum, was determined from changes in the depth of a thin chromium marker layer measured by Rutherford backscattering. Net Mo erosion was found to be approximately 150 nm near the outer divertor strike point, and much less everywhere else. Gross erosion rates by sputtering were estimated using ion energies and fluxes obtained from Langmuir probe measurements of edge-plasma conditions. Predicted net erosion using calculated gross erosion with prompt redeposition and measured net erosion agree within a factor of 3. Sputtering by boron and molybdenum impurities dominates erosion.
Magnetic Fusion Energy
Author: George Neilson
Publisher: Woodhead Publishing
ISBN: 0081003269
Category : Science
Languages : en
Pages : 634
Book Description
Magnetic Fusion Energy: From Experiments to Power Plants is a timely exploration of the field, giving readers an understanding of the experiments that brought us to the threshold of the ITER era, as well as the physics and technology research needed to take us beyond ITER to commercial fusion power plants. With the start of ITER construction, the world's magnetic fusion energy (MFE) enterprise has begun a new era. The ITER scientific and technical (S&T) basis is the result of research on many fusion plasma physics experiments over a period of decades. Besides ITER, the scope of fusion research must be broadened to create the S&T basis for practical fusion power plants, systems that will continuously convert the energy released from a burning plasma to usable electricity, operating for years with only occasional interruptions for scheduled maintenance. - Provides researchers in academia and industry with an authoritative overview of the significant fusion energy experiments - Considers the pathway towards future development of magnetic fusion energy power plants - Contains experts contributions from editors and others who are well known in the field
Publisher: Woodhead Publishing
ISBN: 0081003269
Category : Science
Languages : en
Pages : 634
Book Description
Magnetic Fusion Energy: From Experiments to Power Plants is a timely exploration of the field, giving readers an understanding of the experiments that brought us to the threshold of the ITER era, as well as the physics and technology research needed to take us beyond ITER to commercial fusion power plants. With the start of ITER construction, the world's magnetic fusion energy (MFE) enterprise has begun a new era. The ITER scientific and technical (S&T) basis is the result of research on many fusion plasma physics experiments over a period of decades. Besides ITER, the scope of fusion research must be broadened to create the S&T basis for practical fusion power plants, systems that will continuously convert the energy released from a burning plasma to usable electricity, operating for years with only occasional interruptions for scheduled maintenance. - Provides researchers in academia and industry with an authoritative overview of the significant fusion energy experiments - Considers the pathway towards future development of magnetic fusion energy power plants - Contains experts contributions from editors and others who are well known in the field
Diagnostics for Experimental Thermonuclear Fusion Reactors
Author: Giuseppe Gorini
Publisher: Springer Science & Business Media
ISBN: 1461303699
Category : Science
Languages : en
Pages : 631
Book Description
This book of proceedings collects the papers presented at the Workshop on Diagnostics for ITER, held at Villa Monastero, Varenna (Italy), from August 28 to September 1, 1995. The Workshop was organised by the International School of Plasma Physics "Piero Caldirola. " Established in 1971, the ISPP has organised over fifty advanced courses and workshops on topics mainly related to plasma physics. In particular, courses and workshops on plasma diagnostics (previously held in 1975, 1978, 1982, 1986, and 1991) can be considered milestones in the history of this institution. Looking back at the proceedings of the previous meetings in Varenna, one can appreciate the rapid progress in the field of plasma diagnostics over the past 20 years. The 1995 workshop was co-organised by the Istituto di Fisica del Plasma of the National Research Council (CNR). In contrast to previous Varenna meetings on diagnostics, which have covered diagnostics in present-day tokamaks and which have had a substantial tutorial component, the 1995 workshop concentrated specifically on the problems and challenges of ITER diagnostics. ITER (the International Thennonuclear Experimental Reactor, a joint venture of Europe, Japan, Russia, and the United States, presently under design) will need to measure a wide range of plasma parameters in order to reach and sustain high levels of fusion power. A list of the measurement requirements together with the parameter ranges, target measurement resolutions, and accuracies provides the starting point for selecting a list of candidate diagnostic systems.
Publisher: Springer Science & Business Media
ISBN: 1461303699
Category : Science
Languages : en
Pages : 631
Book Description
This book of proceedings collects the papers presented at the Workshop on Diagnostics for ITER, held at Villa Monastero, Varenna (Italy), from August 28 to September 1, 1995. The Workshop was organised by the International School of Plasma Physics "Piero Caldirola. " Established in 1971, the ISPP has organised over fifty advanced courses and workshops on topics mainly related to plasma physics. In particular, courses and workshops on plasma diagnostics (previously held in 1975, 1978, 1982, 1986, and 1991) can be considered milestones in the history of this institution. Looking back at the proceedings of the previous meetings in Varenna, one can appreciate the rapid progress in the field of plasma diagnostics over the past 20 years. The 1995 workshop was co-organised by the Istituto di Fisica del Plasma of the National Research Council (CNR). In contrast to previous Varenna meetings on diagnostics, which have covered diagnostics in present-day tokamaks and which have had a substantial tutorial component, the 1995 workshop concentrated specifically on the problems and challenges of ITER diagnostics. ITER (the International Thennonuclear Experimental Reactor, a joint venture of Europe, Japan, Russia, and the United States, presently under design) will need to measure a wide range of plasma parameters in order to reach and sustain high levels of fusion power. A list of the measurement requirements together with the parameter ranges, target measurement resolutions, and accuracies provides the starting point for selecting a list of candidate diagnostic systems.
Fusión Nuclear
Author:
Publisher:
ISBN:
Category : Electronic journals
Languages : en
Pages : 504
Book Description
Publisher:
ISBN:
Category : Electronic journals
Languages : en
Pages : 504
Book Description
Calculation of Molybdenum Sputtering from the Limiter in Alcator C
Author: B. Lipschultz
Publisher:
ISBN:
Category :
Languages : en
Pages : 28
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 28
Book Description
The Dynamics of Hydrogenic Retention in Irradiated Molybdenum
Author: Graham Michael Wright
Publisher:
ISBN:
Category :
Languages : en
Pages : 210
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 210
Book Description