S. Raftopoulos - Academia.edu (original) (raw)
Papers by S. Raftopoulos
Bulletin of the American Physical Society, 2016
The Princeton MRI Experiment investigates the MRI in a magnetized cylindrical liquid Gallium Coue... more The Princeton MRI Experiment investigates the MRI in a magnetized cylindrical liquid Gallium Couette flow with inner and outer radii of 7cm and 21cm, and height 28cm. At Reynolds Number of 10 7 we expect to destabilize several modes of the MRI in the presence of a 0.5T axial magnetic field. Ekman effects are reduced via a pair of differentially rotating rings at the end caps. After flow characterization with water, the apparatus was filled with Gallium to search for signatures of the MRI: an amplified radial magnetic field, and enhanced turbulent viscosity coupling the cylinders. Initial diagnostics measure torque and external radial B fields. In the future internal magnetic field and flow diagnostics will be added. Our main objectives are to (1) clearly demonstrate MRI; (2) study its nonlinear behavior and angular momentum transport; (3) compare with simulations similar to those used in astrophysical disks. This work is supported by the US DOE, NSF, and NASA.
Proceedings of the 19th IEEE/IPSS Symposium on Fusion Engineering. 19th SOFE (Cat. No.02CH37231)
Attention has focused recently on flowing liquid lithium as a first wall for a reactor because of... more Attention has focused recently on flowing liquid lithium as a first wall for a reactor because of its potentially attractive physics and engineering features. In order t o test the suitability of liquid lithium as a plasma facing component, the Current Drive experiment
Fusion Science and Technology, 2019
The National Spherical Torus eXperiment Upgrade (NSTX-U) is an innovative magnetic fusion device ... more The National Spherical Torus eXperiment Upgrade (NSTX-U) is an innovative magnetic fusion device constructed at the Princeton Plasma Physics Laboratory (PPPL). In 2016, because of the failure of the PF-1a upper divertor coil, which experienced a coolant blockage, the NSTX-U operation was suspended. A postmortem investigation indicated that an undetected gradual deterioration of coil inductance preceded the coolant blockage leading up to the operational suspension. The project team decided that all inner poiloidal field (PF) upper and lower coil pairs, denoted PF-1a, PF-1b, and PF-1c, shall be replaced with new coils of improved design and manufacture. The new prototype inner PF coils from four suppliers across the globe were evaluated at PPPL following a prototype technical evaluation procedure. Mechanical inspection and electrical testing were performed to qualify each supplier. This paper discusses the details of the mechanical and electrical tests and measurements performed on the complete coils. The test results were used to assess quality of turn-to-turn and turn-to-ground insulations of the prototype coils. Two prototype coils were power tested at PPPL for five pulses to reach its rated current and maximum temperature following the completion of low-power electrical testing. During pulses, the conductors experience a near adiabatic temperature rise and hoop stress. Between pulses, cold water enters the inlet, and a cooling wave propagates through the coils as slugs of cold water heat up to the conductor temperature and then pass through the coil to the outlet. Results show that full power testing did not change coil electrical characteristics. Each prototype coil was then sectioned into two halves to permit examination of the internal insulation, conductor spacing, and vacuum pressure impregnation quality. The high-voltage breakdown test of sectioned coils was performed to evaluate turn and ground insulation breakdown voltage. The estimate for the production coils is based largely on the experience learned from the prototype coil program. The first production coil will be delivered to PPPL for testing by January 2020.
Fusion Engineering and Design, 2009
The National Compact Stellarator Experiment (NCSX) has been under construction at the Princeton P... more The National Compact Stellarator Experiment (NCSX) has been under construction at the Princeton Plasma Physics Laboratory (PPPL) in partnership with the Oak Ridge National Laboratory (ORNL). The stellarator core is designed to produce a compact 3D plasma that combines stellarator and tokamak physics advantages. The complex geometry and tight fabrication tolerances of NCSX create some unique engineering and assembly challenges. The NCSX project was cancelled in May 2008; construction activities are presently being phased out in an orderly fashion. This paper will describe the progress of the fabrication and assembly activities of NCSX. Completion of the coil fabrication is on track for the summer of 2008. All three of the vacuum vessel 120 • sections have been delivered. Assembly of vacuum vessel services began in May 2006 and is now complete. Assembly of the modular coils into 3-packs for safe storage is presently underway.
Fusion Technology, 2001
This is a preprint of a paper presented at the 14th Topical Meeting on the Technology of Fusion E... more This is a preprint of a paper presented at the 14th Topical Meeting on the Technology of Fusion Energy, October 15-19, 2000 in Park City, Utah and to be published in Fusion Technology.
IEEE Transactions on Plasma Science, 2020
son sınıf Türkçe öğretmen adaylarından, kültürel ve edebî birikimlerini yaratıcı yazma bilgi ve b... more son sınıf Türkçe öğretmen adaylarından, kültürel ve edebî birikimlerini yaratıcı yazma bilgi ve becerileriyle birleştirerek birer fabl örneği oluşturmalarını istenmiştir. Buradan hareketle çalışmanın amacı ileriki mesleki yaşantılarında, sınıflarındaki ders kazanımları bağlamında, bu metodu Türkçe ve değerler eğitimi konusunda kullanabilme becerilerini geliştirmelerini sağlayabilmektir. Nitel bir çalışma olarak desenlenen araştırmada elde edilen veriler, içerik analiziyle ele alınmış, yorumlanmış ve senteze varılmıştır. Bu bağlamda, öğrencilerin bir ders saatinde yazmış oldukları fabl örnekleri incelenmiş hangi değerlerin öne çıkarıldığı, hangi kavramlar üzerinden öğretiler/mesajlar iletildiği tespit edilmiştir. Çalışmanın sonucunda, öğretmen adaylarının fabllarında "erdemli insan"da bulunması gereken temel değerler ve bu değerlerin taşıdığı kıymetli mesajlar gün ışığına çıkarılmıştır. Öneri olarak da Yüksek Öğretimden Millî Eğitime (Örneğin Türkçe Eğitimi Bölümü, Orta Öğretimin tüm kademelerindeki Türkçe Dersleri) öğretim programlarının başta fabl, masal gibi Halk Edebiyatı türleriyle, yaratıcı yazma etkinlikleri bağlamında değerler içerikli güncellenmesinin önemi vurgulanmıştır.
IEEE Transactions on Plasma Science, 2019
The purpose of the effort described here is to model and monitor the insulation shear bonds betwe... more The purpose of the effort described here is to model and monitor the insulation shear bonds between the three conductors of the toroidal field (TF) outer legs. Mechanical failure of the insulation could be a precursor to an electrical failure that could damage the TF inner leg central column, which is more difficult to repair. The shear stress in these bonded layers is proportional to the TF outer-leg out-of-plane (OOP) bending. This is a part of a larger program at National Spherical Tokamak Upgrade to instrument and monitor the structural performance of the machine. Components of the instrumentation plan are shown in this study. Bending of the outer leg due to out-ofplane loads is supported partly by shear in the bond between the three conductors that are bonded together to form the outer leg. Bending stress in the outer conductors provides an indication of the integrity of the shear bond. As a part of the orderly planned increase in operational parameters to 0.8 T (as of Feb 2016 it was at 0.61 T). Ten new FISO gauges were purchased and installed in March 2016. They yielded useful data prior to the forced shutdown due to the failure of PF1aUpper coil. The analytic process used to split out the thermal, in-plane and out-of-plane bending strains is described and compared with the measured results. The measured results provide reasonable benchmarks for the analysis. Ultimately, the main purpose of the instrumentation is to compare coil-to-coil behavior, to watch for consistency. If a coil starts to deviate from the others, the coil can be inspected for possible debonding between the three conductors that make up the outer leg. To properly monitor the full TF system, more channels are needed than Fabry-Pérot systems can provide. The planned fiber-Bragg grating (FBG) system is introduced in this paper. Monitoring and evaluation of the TF outer leg strains are also related to computed quantities that are monitored and protected by the digital coil protection system. Currently, the bending strain is expected to be adequately represented by upper-outer leg global moment sums. This relationship is discussed in this paper.
Operational Experience of the Tritium Purification System
Fusion Technology, 1996
The Tritium Purification System (TPS) is a hydrogen isotope separation system put into operation ... more The Tritium Purification System (TPS) is a hydrogen isotope separation system put into operation within the Tokamak Fusion Test Reactor (TFTR) Tritium Systems. The TPS operates in two stages: extraction of hydrogen isotopes from the TFTR plasma waste effluents via a Palladium/Silver diffuser; and separation of hydrogen isotopes via a multiple-stage cryogenic distillation system. Commissioning of TPS included: Operational testing
Removal of Tritium from TFTR
Fusion Technology, 1996
Operation of the Tokamak Fusion Test Reactor (TFTR) with a mixture of deuterium and tritium fueli... more Operation of the Tokamak Fusion Test Reactor (TFTR) with a mixture of deuterium and tritium fueling has permitted the opportunity to measure the retention of tritium in the graphite limiter and other internal hardware. The use of discharge cleaning techniques and venting to remove the tritium was investigated. The tritium was introduced into TFTR by neutral beam injection and by
Plasma Physics and Controlled Fusion, 2016
This document is intended for publication in the open literature. It is made available on the cle... more This document is intended for publication in the open literature. It is made available on the clear understanding that it may not be further circulated and extracts or references may not be published prior to publication of the original when applicable, or without the consent of the Publications Officer, EUROfusion Programme Management Unit,
Vacuum system design for a 1.2 GeV electron storage ring with non-evaporable getter pumping
AIP Conference Proceedings, 1991
ABSTRACT We describe the design for the vacuum vessel and vacuum pumping system for a 1.2 GeV ele... more ABSTRACT We describe the design for the vacuum vessel and vacuum pumping system for a 1.2 GeV electron storage ring for light source applications. The hybrid vacuum vessel design consists of eight extruded aluminum (6063‐T4) dipole chambers curved to the ring radius of 2.93 m, with interconnecting stainless (304 L) steel straight vessel segments. The dipole chambers contain two 60 milliradian photon exit ports on the outer midplane, and an integral pumping chamber on the inner midplane which provides 500 1/s ⋅ m of active gas pumping with a circumferential array of a non‐evaporable getter (NEG) material. Ion pumping stations are distributed along the straight vacuum vessel segments to provide for pumping of CH4 and noble gases. The distributed pumping provided by the NEG offers a factor of five to ten times larger pumping speed in comparison to conventional designs based solely on the use of discrete or distributed ion pumps. Externally bonded cooling tubes on the dipole chambers offer a cost effective and fault tolerant means of removing the x‐ray heat load. Estimates of the conditioning time for the vacuum vessel are presented based on the recent photodesorption data from aluminum surfaces.
21st IEEE/NPS Symposium on Fusion Engineering SOFE 05, 2005
20th IEEE/NPSS Symposium onFusion Engineering, 2003.
The modular coils on the National Compact Stellarator Experiment (NCSX) present a number of signi... more The modular coils on the National Compact Stellarator Experiment (NCSX) present a number of significant engineering challenges due to their complex shapes, requirements for high dimensional accuracy and the high current density required in the modular coils due to space constraints. In order to address these challenges, an R&D program was established to develop the conductor, insulation scheme, manufacturing techniques, and procedures. A prototype winding named Twisted Racetrack Coil (TRC) was of particular importance in dealing with these challenges. The TRC included a complex shaped winding form, conductor, insulation scheme, leads and termination, cooling system and coil clamps typical of the modular coil design. Even though the TRC is smaller in size than a modular coil, its similar complex geometry provided invaluable information in developing the final design, metrology techniques and development of manufacturing procedures. In addition a discussion of the development of the copper rope conductor including "Keystoning" concerns; the epoxy impregnation system (VPI) plus the tooling and equipment required to manufacture the modular coils will be presented. I. Lower Conductor Leads Winding Form / Shell Chill Plate Coolant Tube VPI "Bag" Mold Coil Clamp Winding Packs Copper Cladding Groundwrap insulation This work is supported by the US DOE under contract Number DE-AC 02-76-CH03073
Tokamak experiments have shown the benefits of lithium wall coatings in improving plasma performa... more Tokamak experiments have shown the benefits of lithium wall coatings in improving plasma performance. The CDX-U spherical torus will be the first device where the plasma-surface interaction is dominated by a liquid lithum wall. Following initial experiments with a liquid lithium rail limiter constructed by UCSD, studies using a fully axisymmetric toroidal liquid lithium belt limiter will be performed. This
Overview of the TFTR D&D program
Proceedings of the 19th IEEE/IPSS Symposium on Fusion Engineering. 19th SOFE (Cat. No.02CH37231)
The Tokamak Fusion Test Reactor (TFTR) operated for 15 years, from 1982 to 1997. From November 19... more The Tokamak Fusion Test Reactor (TFTR) operated for 15 years, from 1982 to 1997. From November 1993 to April 1997 a mixture of deuterium-tritium (D-T) was used to fuel experiments, leaving the reactor system in an activated and contaminated state. In this condition, the removal of the TFTR and its subsystems is greatly complicated. In 1999, PPPL commenced the TFTR
Measurements of tritium retention and removal on the Tokamak Fusion Test Reactor
Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, 1996
... Of the 7163 Ci remaining tritium in the in-vessel inven-tory on 2 January 1996, 5000 Ci is co... more ... Of the 7163 Ci remaining tritium in the in-vessel inven-tory on 2 January 1996, 5000 Ci is considered to be tena-ciously held with respect to accidental release scenarios and is accounted for separately, apart from the material in pro-cess. ...
Journal of Nuclear Materials, 1995
TFTR has begun its campaign to study deuterium-tritium fusion under reactor-like conditions. Vari... more TFTR has begun its campaign to study deuterium-tritium fusion under reactor-like conditions. Variable amounts of deuterium and tritium neutral beam power have been used to maximize fusion power, study alpha heating, investigate alpha particle confinement, and search for alpha driven plasma instabilities. Additional areas of study include energy and
Bulletin of the American Physical Society, 2016
The Princeton MRI Experiment investigates the MRI in a magnetized cylindrical liquid Gallium Coue... more The Princeton MRI Experiment investigates the MRI in a magnetized cylindrical liquid Gallium Couette flow with inner and outer radii of 7cm and 21cm, and height 28cm. At Reynolds Number of 10 7 we expect to destabilize several modes of the MRI in the presence of a 0.5T axial magnetic field. Ekman effects are reduced via a pair of differentially rotating rings at the end caps. After flow characterization with water, the apparatus was filled with Gallium to search for signatures of the MRI: an amplified radial magnetic field, and enhanced turbulent viscosity coupling the cylinders. Initial diagnostics measure torque and external radial B fields. In the future internal magnetic field and flow diagnostics will be added. Our main objectives are to (1) clearly demonstrate MRI; (2) study its nonlinear behavior and angular momentum transport; (3) compare with simulations similar to those used in astrophysical disks. This work is supported by the US DOE, NSF, and NASA.
Proceedings of the 19th IEEE/IPSS Symposium on Fusion Engineering. 19th SOFE (Cat. No.02CH37231)
Attention has focused recently on flowing liquid lithium as a first wall for a reactor because of... more Attention has focused recently on flowing liquid lithium as a first wall for a reactor because of its potentially attractive physics and engineering features. In order t o test the suitability of liquid lithium as a plasma facing component, the Current Drive experiment
Fusion Science and Technology, 2019
The National Spherical Torus eXperiment Upgrade (NSTX-U) is an innovative magnetic fusion device ... more The National Spherical Torus eXperiment Upgrade (NSTX-U) is an innovative magnetic fusion device constructed at the Princeton Plasma Physics Laboratory (PPPL). In 2016, because of the failure of the PF-1a upper divertor coil, which experienced a coolant blockage, the NSTX-U operation was suspended. A postmortem investigation indicated that an undetected gradual deterioration of coil inductance preceded the coolant blockage leading up to the operational suspension. The project team decided that all inner poiloidal field (PF) upper and lower coil pairs, denoted PF-1a, PF-1b, and PF-1c, shall be replaced with new coils of improved design and manufacture. The new prototype inner PF coils from four suppliers across the globe were evaluated at PPPL following a prototype technical evaluation procedure. Mechanical inspection and electrical testing were performed to qualify each supplier. This paper discusses the details of the mechanical and electrical tests and measurements performed on the complete coils. The test results were used to assess quality of turn-to-turn and turn-to-ground insulations of the prototype coils. Two prototype coils were power tested at PPPL for five pulses to reach its rated current and maximum temperature following the completion of low-power electrical testing. During pulses, the conductors experience a near adiabatic temperature rise and hoop stress. Between pulses, cold water enters the inlet, and a cooling wave propagates through the coils as slugs of cold water heat up to the conductor temperature and then pass through the coil to the outlet. Results show that full power testing did not change coil electrical characteristics. Each prototype coil was then sectioned into two halves to permit examination of the internal insulation, conductor spacing, and vacuum pressure impregnation quality. The high-voltage breakdown test of sectioned coils was performed to evaluate turn and ground insulation breakdown voltage. The estimate for the production coils is based largely on the experience learned from the prototype coil program. The first production coil will be delivered to PPPL for testing by January 2020.
Fusion Engineering and Design, 2009
The National Compact Stellarator Experiment (NCSX) has been under construction at the Princeton P... more The National Compact Stellarator Experiment (NCSX) has been under construction at the Princeton Plasma Physics Laboratory (PPPL) in partnership with the Oak Ridge National Laboratory (ORNL). The stellarator core is designed to produce a compact 3D plasma that combines stellarator and tokamak physics advantages. The complex geometry and tight fabrication tolerances of NCSX create some unique engineering and assembly challenges. The NCSX project was cancelled in May 2008; construction activities are presently being phased out in an orderly fashion. This paper will describe the progress of the fabrication and assembly activities of NCSX. Completion of the coil fabrication is on track for the summer of 2008. All three of the vacuum vessel 120 • sections have been delivered. Assembly of vacuum vessel services began in May 2006 and is now complete. Assembly of the modular coils into 3-packs for safe storage is presently underway.
Fusion Technology, 2001
This is a preprint of a paper presented at the 14th Topical Meeting on the Technology of Fusion E... more This is a preprint of a paper presented at the 14th Topical Meeting on the Technology of Fusion Energy, October 15-19, 2000 in Park City, Utah and to be published in Fusion Technology.
IEEE Transactions on Plasma Science, 2020
son sınıf Türkçe öğretmen adaylarından, kültürel ve edebî birikimlerini yaratıcı yazma bilgi ve b... more son sınıf Türkçe öğretmen adaylarından, kültürel ve edebî birikimlerini yaratıcı yazma bilgi ve becerileriyle birleştirerek birer fabl örneği oluşturmalarını istenmiştir. Buradan hareketle çalışmanın amacı ileriki mesleki yaşantılarında, sınıflarındaki ders kazanımları bağlamında, bu metodu Türkçe ve değerler eğitimi konusunda kullanabilme becerilerini geliştirmelerini sağlayabilmektir. Nitel bir çalışma olarak desenlenen araştırmada elde edilen veriler, içerik analiziyle ele alınmış, yorumlanmış ve senteze varılmıştır. Bu bağlamda, öğrencilerin bir ders saatinde yazmış oldukları fabl örnekleri incelenmiş hangi değerlerin öne çıkarıldığı, hangi kavramlar üzerinden öğretiler/mesajlar iletildiği tespit edilmiştir. Çalışmanın sonucunda, öğretmen adaylarının fabllarında "erdemli insan"da bulunması gereken temel değerler ve bu değerlerin taşıdığı kıymetli mesajlar gün ışığına çıkarılmıştır. Öneri olarak da Yüksek Öğretimden Millî Eğitime (Örneğin Türkçe Eğitimi Bölümü, Orta Öğretimin tüm kademelerindeki Türkçe Dersleri) öğretim programlarının başta fabl, masal gibi Halk Edebiyatı türleriyle, yaratıcı yazma etkinlikleri bağlamında değerler içerikli güncellenmesinin önemi vurgulanmıştır.
IEEE Transactions on Plasma Science, 2019
The purpose of the effort described here is to model and monitor the insulation shear bonds betwe... more The purpose of the effort described here is to model and monitor the insulation shear bonds between the three conductors of the toroidal field (TF) outer legs. Mechanical failure of the insulation could be a precursor to an electrical failure that could damage the TF inner leg central column, which is more difficult to repair. The shear stress in these bonded layers is proportional to the TF outer-leg out-of-plane (OOP) bending. This is a part of a larger program at National Spherical Tokamak Upgrade to instrument and monitor the structural performance of the machine. Components of the instrumentation plan are shown in this study. Bending of the outer leg due to out-ofplane loads is supported partly by shear in the bond between the three conductors that are bonded together to form the outer leg. Bending stress in the outer conductors provides an indication of the integrity of the shear bond. As a part of the orderly planned increase in operational parameters to 0.8 T (as of Feb 2016 it was at 0.61 T). Ten new FISO gauges were purchased and installed in March 2016. They yielded useful data prior to the forced shutdown due to the failure of PF1aUpper coil. The analytic process used to split out the thermal, in-plane and out-of-plane bending strains is described and compared with the measured results. The measured results provide reasonable benchmarks for the analysis. Ultimately, the main purpose of the instrumentation is to compare coil-to-coil behavior, to watch for consistency. If a coil starts to deviate from the others, the coil can be inspected for possible debonding between the three conductors that make up the outer leg. To properly monitor the full TF system, more channels are needed than Fabry-Pérot systems can provide. The planned fiber-Bragg grating (FBG) system is introduced in this paper. Monitoring and evaluation of the TF outer leg strains are also related to computed quantities that are monitored and protected by the digital coil protection system. Currently, the bending strain is expected to be adequately represented by upper-outer leg global moment sums. This relationship is discussed in this paper.
Operational Experience of the Tritium Purification System
Fusion Technology, 1996
The Tritium Purification System (TPS) is a hydrogen isotope separation system put into operation ... more The Tritium Purification System (TPS) is a hydrogen isotope separation system put into operation within the Tokamak Fusion Test Reactor (TFTR) Tritium Systems. The TPS operates in two stages: extraction of hydrogen isotopes from the TFTR plasma waste effluents via a Palladium/Silver diffuser; and separation of hydrogen isotopes via a multiple-stage cryogenic distillation system. Commissioning of TPS included: Operational testing
Removal of Tritium from TFTR
Fusion Technology, 1996
Operation of the Tokamak Fusion Test Reactor (TFTR) with a mixture of deuterium and tritium fueli... more Operation of the Tokamak Fusion Test Reactor (TFTR) with a mixture of deuterium and tritium fueling has permitted the opportunity to measure the retention of tritium in the graphite limiter and other internal hardware. The use of discharge cleaning techniques and venting to remove the tritium was investigated. The tritium was introduced into TFTR by neutral beam injection and by
Plasma Physics and Controlled Fusion, 2016
This document is intended for publication in the open literature. It is made available on the cle... more This document is intended for publication in the open literature. It is made available on the clear understanding that it may not be further circulated and extracts or references may not be published prior to publication of the original when applicable, or without the consent of the Publications Officer, EUROfusion Programme Management Unit,
Vacuum system design for a 1.2 GeV electron storage ring with non-evaporable getter pumping
AIP Conference Proceedings, 1991
ABSTRACT We describe the design for the vacuum vessel and vacuum pumping system for a 1.2 GeV ele... more ABSTRACT We describe the design for the vacuum vessel and vacuum pumping system for a 1.2 GeV electron storage ring for light source applications. The hybrid vacuum vessel design consists of eight extruded aluminum (6063‐T4) dipole chambers curved to the ring radius of 2.93 m, with interconnecting stainless (304 L) steel straight vessel segments. The dipole chambers contain two 60 milliradian photon exit ports on the outer midplane, and an integral pumping chamber on the inner midplane which provides 500 1/s ⋅ m of active gas pumping with a circumferential array of a non‐evaporable getter (NEG) material. Ion pumping stations are distributed along the straight vacuum vessel segments to provide for pumping of CH4 and noble gases. The distributed pumping provided by the NEG offers a factor of five to ten times larger pumping speed in comparison to conventional designs based solely on the use of discrete or distributed ion pumps. Externally bonded cooling tubes on the dipole chambers offer a cost effective and fault tolerant means of removing the x‐ray heat load. Estimates of the conditioning time for the vacuum vessel are presented based on the recent photodesorption data from aluminum surfaces.
21st IEEE/NPS Symposium on Fusion Engineering SOFE 05, 2005
20th IEEE/NPSS Symposium onFusion Engineering, 2003.
The modular coils on the National Compact Stellarator Experiment (NCSX) present a number of signi... more The modular coils on the National Compact Stellarator Experiment (NCSX) present a number of significant engineering challenges due to their complex shapes, requirements for high dimensional accuracy and the high current density required in the modular coils due to space constraints. In order to address these challenges, an R&D program was established to develop the conductor, insulation scheme, manufacturing techniques, and procedures. A prototype winding named Twisted Racetrack Coil (TRC) was of particular importance in dealing with these challenges. The TRC included a complex shaped winding form, conductor, insulation scheme, leads and termination, cooling system and coil clamps typical of the modular coil design. Even though the TRC is smaller in size than a modular coil, its similar complex geometry provided invaluable information in developing the final design, metrology techniques and development of manufacturing procedures. In addition a discussion of the development of the copper rope conductor including "Keystoning" concerns; the epoxy impregnation system (VPI) plus the tooling and equipment required to manufacture the modular coils will be presented. I. Lower Conductor Leads Winding Form / Shell Chill Plate Coolant Tube VPI "Bag" Mold Coil Clamp Winding Packs Copper Cladding Groundwrap insulation This work is supported by the US DOE under contract Number DE-AC 02-76-CH03073
Tokamak experiments have shown the benefits of lithium wall coatings in improving plasma performa... more Tokamak experiments have shown the benefits of lithium wall coatings in improving plasma performance. The CDX-U spherical torus will be the first device where the plasma-surface interaction is dominated by a liquid lithum wall. Following initial experiments with a liquid lithium rail limiter constructed by UCSD, studies using a fully axisymmetric toroidal liquid lithium belt limiter will be performed. This
Overview of the TFTR D&D program
Proceedings of the 19th IEEE/IPSS Symposium on Fusion Engineering. 19th SOFE (Cat. No.02CH37231)
The Tokamak Fusion Test Reactor (TFTR) operated for 15 years, from 1982 to 1997. From November 19... more The Tokamak Fusion Test Reactor (TFTR) operated for 15 years, from 1982 to 1997. From November 1993 to April 1997 a mixture of deuterium-tritium (D-T) was used to fuel experiments, leaving the reactor system in an activated and contaminated state. In this condition, the removal of the TFTR and its subsystems is greatly complicated. In 1999, PPPL commenced the TFTR
Measurements of tritium retention and removal on the Tokamak Fusion Test Reactor
Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, 1996
... Of the 7163 Ci remaining tritium in the in-vessel inven-tory on 2 January 1996, 5000 Ci is co... more ... Of the 7163 Ci remaining tritium in the in-vessel inven-tory on 2 January 1996, 5000 Ci is considered to be tena-ciously held with respect to accidental release scenarios and is accounted for separately, apart from the material in pro-cess. ...
Journal of Nuclear Materials, 1995
TFTR has begun its campaign to study deuterium-tritium fusion under reactor-like conditions. Vari... more TFTR has begun its campaign to study deuterium-tritium fusion under reactor-like conditions. Variable amounts of deuterium and tritium neutral beam power have been used to maximize fusion power, study alpha heating, investigate alpha particle confinement, and search for alpha driven plasma instabilities. Additional areas of study include energy and