ABSTRACT To achieve the desired goals of the physics mission of NCSX (to develop, demonstrate and... more ABSTRACT To achieve the desired goals of the physics mission of NCSX (to develop, demonstrate and test our understanding of compact optimized stellarators) it is important to design a flexible coil set which can vary the plasma configuration about the optimized design point. In this poster, we describe techniques we have developed to examine the plasma control and flexibility of candidate NCSX coil sets, and demonstrate the ability of the NCSX coils to independently vary key physics properties of the configuration, such as the kink stability and degree of quasisymmetry.
2013 IEEE 25th Symposium on Fusion Engineering (SOFE), 2013
ABSTRACT ITER is incorporating two types of In Vessel Coils (IVCs): ELM Coils to mitigate Edge Lo... more ABSTRACT ITER is incorporating two types of In Vessel Coils (IVCs): ELM Coils to mitigate Edge Localized Modes and VS Coils to provide Vertical Stabilization of the plasma. Strong coupling with the plasma is required so that the ELM and VS Coils can meet their performance requirements. Accordingly, the IVCs are in close proximity to the plasma, mounted just behind the Blanket Shield Modules. This location results in a radiation and temperature environment that is severe necessitating new solutions for material selection as well as challenging analysis and design solutions. Fitting the coil systems in between the blanket shield modules and the vacuum vessel leads to difficult integration with diagnostic cabling and cooling water manifolds. The design of the IVCs is now progressing towards a final design scheduled for late CY 13. The project is a collaboration between the Princeton Plasma Physics Laboratory in Princeton NJ, the Chinese Academy of Sciences (ASIPP) in Hefei China and the ITER Organization. An extensive thermal and stress analysis to evaluate the effects of the high temperatures and electromagnetic loads on the In Vessel Coils has been undertaken. Manufacturing development is underway at ASIPP to develop the processes necessary to build ELM coil and VS Coil prototypes. This paper will outline the design and analysis issues as well as review the manufacturing development required to address these requirements and plans for prototypes.
ABSTRACT A novel concept for incorporating a iron core transformer within a axisymmetric toroidal... more ABSTRACT A novel concept for incorporating a iron core transformer within a axisymmetric toroidal plasma containment device with a high neutron flux is described. This design enables conceptual design of low aspect ratio devices which employ standard transformer-driven plasma startup by using all-metal high resistance separators between the toroidal field windings. This design avoids the inherent problems of a multiturn air core transformer which will inevitably suffer from strong neutron bombardment and hence lose the integrity of its insulation, both through long term material degradation and short term neutron- induced conductivity.. A full 3-dimensional model of the concept has been developed within the MAXWELL program and the resultant loop voltage calculated. The utility of the result is found to be dependent on the resistivity of the high resistance separators. Useful loop voltage time histories have been obtained using achievable resistivities.
The effects of high-beta operation of ISX-B were evaluated by installing a new poloidal field (PF... more The effects of high-beta operation of ISX-B were evaluated by installing a new poloidal field (PF) coil set which subjects the coils to higher out-of-plane loads. It was found that the iron core affects the load distribution; the forces were calculated using the GFUN-3D code which takes the iron core effects into account. The internal load distribution was determined by
2007 IEEE 22nd Symposium on Fusion Engineering, 2007
... dumps. The magnetic coil system will employ liquid helium cooled 5083 Aluminum alloy casing o... more ... dumps. The magnetic coil system will employ liquid helium cooled 5083 Aluminum alloy casing on a Rutherford NbTi cable. ... support. The conceptual design and corresponding preliminary load and field calculations will be presented. ...
ABSTRACT The National Compact Stellarator Experiment (NCSX) is the first of a new class of stella... more ABSTRACT The National Compact Stellarator Experiment (NCSX) is the first of a new class of stellarators known as "compact stellarators". The differentiating feature of a compact stellarator is the use of plasma current in combination with external fields to accomplish shaping and confinement. The modular coil set for NCSX is comprised of 18 complex shaped windings contained in an integral shell. There are three distinct modular coil shapes; six of each embody the complete set. To fabricate these windings to the precise shapes required, stranded copper cable conductor is wound on stainless steel winding forms. A single modular coil conductor turn is comprised of four rectangular compacted copper ropes in a two-by-two configuration which are vacuum impregnated. Groups of conductors are placed in a mold where they are bonded into bundles forming the modular coils. An in-depth mechanical test program is required to verify the integrity of the modular coil manufacturing process. This would be followed by an extensive test program, which would evaluate the vacuum impregnation of the coil and determine the thermally dependent mechanical properties of the coils. Properties to be evaluated include tension, compression, shear and flexural moduli and strengths. Thermal coefficients of expansion for various coil components are to be determined over the entire range of NCSX operating temperatures. Other specific tests, including an evaluation of resin cure shrinkage, are also planned. This paper will report the findings and results of this test program to date.
2011 IEEE/NPSS 24th Symposium on Fusion Engineering, 2011
ABSTRACT ITER will incorporate In Vessel Coils (IVCs) as a method of stabilizing “Edge Localized ... more ABSTRACT ITER will incorporate In Vessel Coils (IVCs) as a method of stabilizing “Edge Localized Modes” (ELM) and providing “Vertical Stabilization” (VS). To meet the ELM and VS Coil requirements strong coupling with the plasma is required so that it is necessary for the coils to be installed in the vessel just behind the blanket shield modules. Due to this close proximity to the plasma the radiation and temperature environment is severe and conventional electrical insulation materials and processes cannot be used. The development of mineral insulated conductor technology has been required in the IVC design to deal with this high radiation and high temperature environment. While mineral insulated conductor technology is not new, building a large magnet with high current carrying capability and a conductor diameter larger than the mineral insulated conductor currently manufactured requires R&D and the extension of existing technologies. A 59mm Stainless Steel Jacketed Mineral Insulated Conductor (SSMIC) using MgO is being developed for this application. The IVC ELM and VS coils design includes both the development of the fabrication techniques for the SSMIC and the design and analysis of the ELM and VS Coil assemblies. The ELM coil assemblies consist of nine toroidal sectors of three (upper, midplane, and lower) 6-turn rectangular "picture frame coils" for a total of 27 coils mounted to the vacuum vessel. The ELM coil structural design must provide enough flexibility to relieve the thermal stresses in the coil while providing the stiffness to resist the high Lorentz (magnetic) loads on the coil. To achieve the required fatigue lifetime the ELM SSMIC conductors use a water cooled CuCrZr conductor. The VS coils consist of one upper and one lower 4-turn solenoid "ring" coil connected in an anti-series "saddle" arrangement. Because it is less stressed than the ELM coil conductor the VS SSMIC conductor use water cooled Cu instead of CuCrZr. Thi- - s paper summarizes the design, development, and testing to date of the SSMIC conductor as well as the design and analysis of the VS and ELM coil assemblies. Joining and assembly techniques for the SSMIC conductor are also discussed.
Proceedings of the 19th IEEE/IPSS Symposium on Fusion Engineering. 19th SOFE (Cat. No.02CH37231), 2002
... R. Lindenberg, R. Parsells, E. Perry, K. Rule, J. Semler, J. Stacy, M. Viola, I. Zatz ... 199... more ... R. Lindenberg, R. Parsells, E. Perry, K. Rule, J. Semler, J. Stacy, M. Viola, I. Zatz ... 1993 to April 1997 a mixture of Deuterium-Tritium @T) was used to fuel experiments, leaving ... layers of protective clothing (cloth jumpsuits, rubber gloves and boots), as well as full-face, supplied-air ...
IEEJ Transactions on Fundamentals and Materials, 2005
An overview of the research capabilities and the future plans on the MA-class National Spherical ... more An overview of the research capabilities and the future plans on the MA-class National Spherical Torus Experiment (NSTX) at Princeton is presented. NSTX research is exploring the scientific benefits of modifying the field line structure from that in more conventional aspect ratio devices, such as the tokamak. The relevant scientific issues pursued on NSTX include energy confinement, MHD stability at
ABSTRACT To achieve the desired goals of the physics mission of NCSX (to develop, demonstrate and... more ABSTRACT To achieve the desired goals of the physics mission of NCSX (to develop, demonstrate and test our understanding of compact optimized stellarators) it is important to design a flexible coil set which can vary the plasma configuration about the optimized design point. In this poster, we describe techniques we have developed to examine the plasma control and flexibility of candidate NCSX coil sets, and demonstrate the ability of the NCSX coils to independently vary key physics properties of the configuration, such as the kink stability and degree of quasisymmetry.
2013 IEEE 25th Symposium on Fusion Engineering (SOFE), 2013
ABSTRACT ITER is incorporating two types of In Vessel Coils (IVCs): ELM Coils to mitigate Edge Lo... more ABSTRACT ITER is incorporating two types of In Vessel Coils (IVCs): ELM Coils to mitigate Edge Localized Modes and VS Coils to provide Vertical Stabilization of the plasma. Strong coupling with the plasma is required so that the ELM and VS Coils can meet their performance requirements. Accordingly, the IVCs are in close proximity to the plasma, mounted just behind the Blanket Shield Modules. This location results in a radiation and temperature environment that is severe necessitating new solutions for material selection as well as challenging analysis and design solutions. Fitting the coil systems in between the blanket shield modules and the vacuum vessel leads to difficult integration with diagnostic cabling and cooling water manifolds. The design of the IVCs is now progressing towards a final design scheduled for late CY 13. The project is a collaboration between the Princeton Plasma Physics Laboratory in Princeton NJ, the Chinese Academy of Sciences (ASIPP) in Hefei China and the ITER Organization. An extensive thermal and stress analysis to evaluate the effects of the high temperatures and electromagnetic loads on the In Vessel Coils has been undertaken. Manufacturing development is underway at ASIPP to develop the processes necessary to build ELM coil and VS Coil prototypes. This paper will outline the design and analysis issues as well as review the manufacturing development required to address these requirements and plans for prototypes.
ABSTRACT A novel concept for incorporating a iron core transformer within a axisymmetric toroidal... more ABSTRACT A novel concept for incorporating a iron core transformer within a axisymmetric toroidal plasma containment device with a high neutron flux is described. This design enables conceptual design of low aspect ratio devices which employ standard transformer-driven plasma startup by using all-metal high resistance separators between the toroidal field windings. This design avoids the inherent problems of a multiturn air core transformer which will inevitably suffer from strong neutron bombardment and hence lose the integrity of its insulation, both through long term material degradation and short term neutron- induced conductivity.. A full 3-dimensional model of the concept has been developed within the MAXWELL program and the resultant loop voltage calculated. The utility of the result is found to be dependent on the resistivity of the high resistance separators. Useful loop voltage time histories have been obtained using achievable resistivities.
The effects of high-beta operation of ISX-B were evaluated by installing a new poloidal field (PF... more The effects of high-beta operation of ISX-B were evaluated by installing a new poloidal field (PF) coil set which subjects the coils to higher out-of-plane loads. It was found that the iron core affects the load distribution; the forces were calculated using the GFUN-3D code which takes the iron core effects into account. The internal load distribution was determined by
2007 IEEE 22nd Symposium on Fusion Engineering, 2007
... dumps. The magnetic coil system will employ liquid helium cooled 5083 Aluminum alloy casing o... more ... dumps. The magnetic coil system will employ liquid helium cooled 5083 Aluminum alloy casing on a Rutherford NbTi cable. ... support. The conceptual design and corresponding preliminary load and field calculations will be presented. ...
ABSTRACT The National Compact Stellarator Experiment (NCSX) is the first of a new class of stella... more ABSTRACT The National Compact Stellarator Experiment (NCSX) is the first of a new class of stellarators known as "compact stellarators". The differentiating feature of a compact stellarator is the use of plasma current in combination with external fields to accomplish shaping and confinement. The modular coil set for NCSX is comprised of 18 complex shaped windings contained in an integral shell. There are three distinct modular coil shapes; six of each embody the complete set. To fabricate these windings to the precise shapes required, stranded copper cable conductor is wound on stainless steel winding forms. A single modular coil conductor turn is comprised of four rectangular compacted copper ropes in a two-by-two configuration which are vacuum impregnated. Groups of conductors are placed in a mold where they are bonded into bundles forming the modular coils. An in-depth mechanical test program is required to verify the integrity of the modular coil manufacturing process. This would be followed by an extensive test program, which would evaluate the vacuum impregnation of the coil and determine the thermally dependent mechanical properties of the coils. Properties to be evaluated include tension, compression, shear and flexural moduli and strengths. Thermal coefficients of expansion for various coil components are to be determined over the entire range of NCSX operating temperatures. Other specific tests, including an evaluation of resin cure shrinkage, are also planned. This paper will report the findings and results of this test program to date.
2011 IEEE/NPSS 24th Symposium on Fusion Engineering, 2011
ABSTRACT ITER will incorporate In Vessel Coils (IVCs) as a method of stabilizing “Edge Localized ... more ABSTRACT ITER will incorporate In Vessel Coils (IVCs) as a method of stabilizing “Edge Localized Modes” (ELM) and providing “Vertical Stabilization” (VS). To meet the ELM and VS Coil requirements strong coupling with the plasma is required so that it is necessary for the coils to be installed in the vessel just behind the blanket shield modules. Due to this close proximity to the plasma the radiation and temperature environment is severe and conventional electrical insulation materials and processes cannot be used. The development of mineral insulated conductor technology has been required in the IVC design to deal with this high radiation and high temperature environment. While mineral insulated conductor technology is not new, building a large magnet with high current carrying capability and a conductor diameter larger than the mineral insulated conductor currently manufactured requires R&D and the extension of existing technologies. A 59mm Stainless Steel Jacketed Mineral Insulated Conductor (SSMIC) using MgO is being developed for this application. The IVC ELM and VS coils design includes both the development of the fabrication techniques for the SSMIC and the design and analysis of the ELM and VS Coil assemblies. The ELM coil assemblies consist of nine toroidal sectors of three (upper, midplane, and lower) 6-turn rectangular "picture frame coils" for a total of 27 coils mounted to the vacuum vessel. The ELM coil structural design must provide enough flexibility to relieve the thermal stresses in the coil while providing the stiffness to resist the high Lorentz (magnetic) loads on the coil. To achieve the required fatigue lifetime the ELM SSMIC conductors use a water cooled CuCrZr conductor. The VS coils consist of one upper and one lower 4-turn solenoid "ring" coil connected in an anti-series "saddle" arrangement. Because it is less stressed than the ELM coil conductor the VS SSMIC conductor use water cooled Cu instead of CuCrZr. Thi- - s paper summarizes the design, development, and testing to date of the SSMIC conductor as well as the design and analysis of the VS and ELM coil assemblies. Joining and assembly techniques for the SSMIC conductor are also discussed.
Proceedings of the 19th IEEE/IPSS Symposium on Fusion Engineering. 19th SOFE (Cat. No.02CH37231), 2002
... R. Lindenberg, R. Parsells, E. Perry, K. Rule, J. Semler, J. Stacy, M. Viola, I. Zatz ... 199... more ... R. Lindenberg, R. Parsells, E. Perry, K. Rule, J. Semler, J. Stacy, M. Viola, I. Zatz ... 1993 to April 1997 a mixture of Deuterium-Tritium @T) was used to fuel experiments, leaving ... layers of protective clothing (cloth jumpsuits, rubber gloves and boots), as well as full-face, supplied-air ...
IEEJ Transactions on Fundamentals and Materials, 2005
An overview of the research capabilities and the future plans on the MA-class National Spherical ... more An overview of the research capabilities and the future plans on the MA-class National Spherical Torus Experiment (NSTX) at Princeton is presented. NSTX research is exploring the scientific benefits of modifying the field line structure from that in more conventional aspect ratio devices, such as the tokamak. The relevant scientific issues pursued on NSTX include energy confinement, MHD stability at
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