jingping chen - Academia.edu (original) (raw)

Papers by jingping chen

Research paper thumbnail of EM Loads on ITER Diagnostics Equatorial Port Plugs 9 and Its In-Port Components During Plasma Disruptions

Fusion Science and Technology, 2017

Abstract International Thermonuclear Experimental Reactor (ITER) diagnostic port plugs perform ma... more Abstract International Thermonuclear Experimental Reactor (ITER) diagnostic port plugs perform many functions including nuclear shielding, structural support of diagnostic system, while allowing for diagnostic access to the plasma. With design advancing, the in-port diagnostic components are integrated into the port plug structure, and the diagnostic shield modules (DSM) are customized to accommodate the in-port diagnostic components. This technical note summarizes results of transient electro-magnetic analysis using Opera 3d in support of recent design activities for ITER diagnostic equatorial port plug (EPP). A complete distribution of disruption loads on each component in EPP9 is presented. Impacts of different design features, such as the locations of the electrical contact, to the EM loads are discussed, and solutions for improving the port structure design are proposed.

Research paper thumbnail of Cryostat Design for the HZB and NHMFL Series-Connected Hybrids

IEEE Transactions on Applied Superconductivity, 2010

... 5 to 7. Fig. 5 is the stress intensity plot of the vacuum vessel under normal oper-ating cond... more ... 5 to 7. Fig. 5 is the stress intensity plot of the vacuum vessel under normal oper-ating condition. The resistive housing tries to inflate because of the internal water pressure. The bore tube looks unsymmetrical because of the insert weight and the misalignment load. ...

Research paper thumbnail of Development of load specifications for the design of ITER diagnostic system and port integration

Fusion Engineering and Design, 2017

ITER is the world's largest fusion device currently under construction in South of France with 50... more ITER is the world's largest fusion device currently under construction in South of France with 50+ diagnostic systems installed inside the port plugs, the interspace or the port cell region of various diagnostic ports. The plasma facing Diagnostic First Wall (DFW) and its supporting Diagnostic Shielding Modules (DSM) are designed to protect the front-end diagnostics from plasma neutron and radiation while providing apertures for diagnostic access to the plasma. The design of ITER port plug (PP) structure assembly including the DFWs, DSMs with in-port diagnostics is largely driven by the electromagnetic (EM) loads induced on these passive structural components during plasma disruptions, and the steady-state thermal loads from plasma volumetric and surface heating during normal operations. The design is significantly influenced by the dynamic response of in-port components attached to the port-specific DSM or PP closure plate as a result of transient EM loads induced on the PP assembly, vacuum vessel (VV) and the port extension during asymmetric plasma Vertical Displacement Events (VDEs). We investigate in this study the worst plasma disruption load cases for diagnostic systems of varying size and location, and summarize the steady-state thermal, transient EM and VV inertial loads for ITER diagnostic systems.

Research paper thumbnail of Analysis of Mechanical Stresses/Strains in Superconducting Wire

Bulletin of the American Physical Society, 2016

Research paper thumbnail of Design and Analysis Progress of US ITER Diagnostic Upper Port #14

IEEE Transactions on Plasma Science, 2018

ITER is the world's largest fusion device currently under construction in the South of France wit... more ITER is the world's largest fusion device currently under construction in the South of France with >50 diagnostic systems to be installed inside the port plugs (PPs), the interspace (IS) or the port cell (PC) region of various diagnostic ports. Four tenant diagnostic systems will be integrated into the upper port 14 (U14), the Upper Wide Angle Viewing System (UWAVS), the Disruption Mitigation System (DMS), the Glow Discharge Cleaning (GDC) system and the Plasma Position Reflectometry (PPR), an ex-vessel tenant installed in the U14 interspace region. Multi-physics analyses were performed for an in-vessel and exvessel component design integration following the ITER port integration requirements and the ITER guideline for Load Specification. Electromagnetic (EM), inertial and heating loads of the main U14 components under various conditions for the diagnostic shield module (DSM) and its internal shielding block attachment design have been summarized. The structural design of in-port components is based on an optimization of the EM load distribution to limit the load impact to the Diagnostic First Wall (DFW) and the tenant diagnostics, and to mitigate the effect of dynamic amplification from asymmetric plasma VDE (Vertical Displacement Event) inertial loads. The DSM needs to provide a sufficient stiffness for the protection of on-board diagnostics and structural integrity of the port integration under the design-driving EM and inertial loads. The in-port diagnostics and mounting supports, on the other hand, are designed to meet the remote handling requirement, while taking into account the thermal loads due to temperature gradient from nuclear heating, as well as matching the relative stiffness among the structural components within the port assembly. Progress on an integrated design and analysis is reported including a seismic analysis of the IS/PC region for extracting tenant interface loads. The design driving loads for tenant systems are presented for the attachment structure design as part of the PP engineering tasks.

Research paper thumbnail of EM Analysis of ITER Diagnostics Upper Port Plugs 14 and 11 During Plasma Disruptions

IEEE Transactions on Plasma Science, 2018

Research paper thumbnail of Selected Composites for High Field Magnets

MRS Proceedings, 2006

The national high magnetic field laboratory builds and uses various high field magnets for fundam... more The national high magnetic field laboratory builds and uses various high field magnets for fundamental research. In building high field magnets, a variety of high strength composites are required because of the Lorentz stresses generated by high field exceeding the strength of most of the materials, particular conductors. For example, a field of 60 T can generate a magnetic pressure that corresponds to a stress in the conductor of 1.5 GPa, which is at the limit of known conducting materials with conductivity higher than 70% International Annealed Copper Standard and sizes suitable for building high field magnets. The design of high field magnets is limited by these forces and, consequently, by the available materials. At the same time, the materials need to have excellent physical properties. For instance, the conductors need to have high electrical conductivity and high specific heat and the superconductors should have high critical current in field and low alternative current loss...

Research paper thumbnail of Resistive Solenoid Development at the NHMFL Based on Irregular Stacking Method

IEEE Transactions on Applied Superconductivity, 2012

ABSTRACT The National High Magnetic Field Laboratory (NHMFL) in Tallahassee, Florida designs, bui... more ABSTRACT The National High Magnetic Field Laboratory (NHMFL) in Tallahassee, Florida designs, builds and operates the world's highest field dc resistive magnets, providing fields up to 36 T in pure resistive systems and up to 45 T in resistive-superconducting hybrids. The NHMFL has several resistive solenoid magnet projects underway presently, including upgrading existing magnets, designing the conical insert for the Helmholtz Center Berlin (HZB), and designing insert coils of the Series-Connected-Hybrid (SCH) for NHMFL. In addition, building the 28 MW all resistive magnets will start in 2012. The method, called irregular stacking, successfully used in the upgrade of the existing magnets in 2009, will be employed in the new upgrades and the design of the new magnet system. In this paper, the progresses of each project are briefly summarized at first. The new technology of irregular stacking is then discussed in detail. In the last section, the application of the technology in future upgrades and the design of the magnets are present.

Research paper thumbnail of The Powered Scattering-Magnet Program at the NHMFL

IEEE Transactions on Applied Superconductivity, 2008

Research paper thumbnail of Recent Progress of the Series-Connected Hybrid Magnet Projects

IEEE Transactions on Applied Superconductivity, 2010

The National High Magnetic Field Laboratory (NHMFL) in Tallahassee, Florida has designed and is n... more The National High Magnetic Field Laboratory (NHMFL) in Tallahassee, Florida has designed and is now constructing two Series Connected Hybrid (SCH) magnets, each connecting a superconducting outsert coil and a resistive Florida Bitter insert coil electrically in series. The SCH to be installed at the NHMFL will produce 36 T and provide 1 ppm maximum field inhomogeneity over a 1 cm diameter spherical volume. The SCH to be installed at the Helmholtz Center Berlin (HZB) in combination with a neutron source will produce 25 T to 30 T depending on the resistive insert. The two magnets have a common design for their cable-in-conduit conductor (CICC) and superconducting outsert coils. The CICC outsert coil winding packs have an inner diameter of 0.6 m and contribute 13.1 T to the central field using three grades of CICC conductors. Each conductor grade carries 20 kA and employs the same type of Nb 3 Sn superconducting wire, but each grade contains different quantities of superconducting wires, different cabling patterns and different aspect ratios. The cryostats and resistive insert coils for the two magnets are different. This paper discusses the progress in CIC conductor and coil fabrication over the last year including specification, qualification and production activities for wire, cable, conductor and coil processing.

Research paper thumbnail of Cryostat Design for the NHMFL Series-Connected Hybrid

IEEE Transactions on Applied Superconductivity, 2011

The National High Magnetic Field Laboratory (NHMFL) is designing a series-connected hybrid magnet... more The National High Magnetic Field Laboratory (NHMFL) is designing a series-connected hybrid magnet, which has a 40 mm diameter vertical warm bore with a cylindrical profile. The magnet will generate a 36 T field with 13 MW power for a high homogeneity version (1 ppm homogeneity) or 40 T for a high field version. This hybrid shares the design of superconducting coil with another SCH designed for Berlin, Germany. The cryostat design is quite different however. In this paper the design of the NHMFL cryostat is presented. The main features are described at first followed by the discussion of the FEA models and results.

Research paper thumbnail of Design and Analysis Progress of ITER Diagnostic Equatorial Port #09

IEEE Transactions on Plasma Science, 2018

ITER is the world's largest fusion device currently under construction in the South of France wit... more ITER is the world's largest fusion device currently under construction in the South of France with >50 diagnostic systems to be installed inside the port plugs (PPs), the interspace (IS) or the port cell (PC) region of various diagnostic ports. The plasma facing Diagnostic First Wall (DFW) and its supporting diagnostic shield modules (DSM) are designed to protect frontend diagnostics from plasma neutron and plasma radiation while providing apertures for diagnostic access to the plasma. The design of ITER port plug structures (PPS) including the DFW and the DSM is largely driven by the electromagnetic (EM) loads included on the PP structural components during plasma major disruptions (MDs) and the vertical displacement events (VDEs). Unlike DFW and DSM, the design of diagnostic system, however, is likely driven by the steady-state thermal loads from plasma volumetric and surface heating and the dynamic response of the in-port components attached to the port-specific DSM or closure plate under transient loads induced on the Vacuum Vessel (VV) and the port extension during asymmetric VDEs. Three tenant diagnostic systems are integrated into the equatorial port 09 (E09). The toroidal interferometer / polarimeter, or TIP system, is installed in the left drawer (DSM3, left looking from plasma) for measuring the plasma density so to control the fuel input. The electron cyclotron emission (ECE) system is installed in the middle drawer (DSM2) to provide the high spatial and temporal resolution measurements of electron temperature evolution and the electron thermal transport inferences. The visible/infrared wide angle viewing system is installed in the right drawer (DSM1) to provide visible and infra-red viewing and temperature data of the first wall for its protection in support of machine operation. The port plug integration design and multi-physics analyses are performed following port integration requirements including the weight limit (45 tones total), shut down dose rate limits, the cooling / heating and structural integrity validation. Mass distribution for TIP and ECE DSMs has been optimized to minimize the total weight by a new design of the boron carbide (B4C) shielding pocket. The lightened DSM maintains its frontend load distribution and the structural stiffness with minimum impact to the DFW so to better protect on-board diagnostics; while still provides sufficient front end stiffness for its structural integrity as well as the diagnostics function requirements.

Research paper thumbnail of 3D Stress-Strain Model of the Nb<formula formulatype="inline"> <tex Notation="TeX">$_{3}$</tex></formula>Sn Wire

IEEE Transactions on Applied Superconductivity, 2011

ABSTRACT The performance of Nb3Sn multifilament wires is highly strain-sensitive. Since the strai... more ABSTRACT The performance of Nb3Sn multifilament wires is highly strain-sensitive. Since the strain in each individual Nb3Sn filament rather than the overall strain on the Nb3Sn wire influences the superconducting properties, it is very important to build a relationship between the internal strain in each Nb3Sn filament and external loads. In this study, a 3D model is developed to address the relationship. It is found that the geometry of the cross-section of the filaments plays an important role in the relationship between the stress and strain.

Research paper thumbnail of EM Loads on ITER Diagnostics Equatorial Port Plugs 9 and Its In-Port Components During Plasma Disruptions

Fusion Science and Technology, 2017

Abstract International Thermonuclear Experimental Reactor (ITER) diagnostic port plugs perform ma... more Abstract International Thermonuclear Experimental Reactor (ITER) diagnostic port plugs perform many functions including nuclear shielding, structural support of diagnostic system, while allowing for diagnostic access to the plasma. With design advancing, the in-port diagnostic components are integrated into the port plug structure, and the diagnostic shield modules (DSM) are customized to accommodate the in-port diagnostic components. This technical note summarizes results of transient electro-magnetic analysis using Opera 3d in support of recent design activities for ITER diagnostic equatorial port plug (EPP). A complete distribution of disruption loads on each component in EPP9 is presented. Impacts of different design features, such as the locations of the electrical contact, to the EM loads are discussed, and solutions for improving the port structure design are proposed.

Research paper thumbnail of Cryostat Design for the HZB and NHMFL Series-Connected Hybrids

IEEE Transactions on Applied Superconductivity, 2010

... 5 to 7. Fig. 5 is the stress intensity plot of the vacuum vessel under normal oper-ating cond... more ... 5 to 7. Fig. 5 is the stress intensity plot of the vacuum vessel under normal oper-ating condition. The resistive housing tries to inflate because of the internal water pressure. The bore tube looks unsymmetrical because of the insert weight and the misalignment load. ...

Research paper thumbnail of Development of load specifications for the design of ITER diagnostic system and port integration

Fusion Engineering and Design, 2017

ITER is the world's largest fusion device currently under construction in South of France with 50... more ITER is the world's largest fusion device currently under construction in South of France with 50+ diagnostic systems installed inside the port plugs, the interspace or the port cell region of various diagnostic ports. The plasma facing Diagnostic First Wall (DFW) and its supporting Diagnostic Shielding Modules (DSM) are designed to protect the front-end diagnostics from plasma neutron and radiation while providing apertures for diagnostic access to the plasma. The design of ITER port plug (PP) structure assembly including the DFWs, DSMs with in-port diagnostics is largely driven by the electromagnetic (EM) loads induced on these passive structural components during plasma disruptions, and the steady-state thermal loads from plasma volumetric and surface heating during normal operations. The design is significantly influenced by the dynamic response of in-port components attached to the port-specific DSM or PP closure plate as a result of transient EM loads induced on the PP assembly, vacuum vessel (VV) and the port extension during asymmetric plasma Vertical Displacement Events (VDEs). We investigate in this study the worst plasma disruption load cases for diagnostic systems of varying size and location, and summarize the steady-state thermal, transient EM and VV inertial loads for ITER diagnostic systems.

Research paper thumbnail of Analysis of Mechanical Stresses/Strains in Superconducting Wire

Bulletin of the American Physical Society, 2016

Research paper thumbnail of Design and Analysis Progress of US ITER Diagnostic Upper Port #14

IEEE Transactions on Plasma Science, 2018

ITER is the world's largest fusion device currently under construction in the South of France wit... more ITER is the world's largest fusion device currently under construction in the South of France with >50 diagnostic systems to be installed inside the port plugs (PPs), the interspace (IS) or the port cell (PC) region of various diagnostic ports. Four tenant diagnostic systems will be integrated into the upper port 14 (U14), the Upper Wide Angle Viewing System (UWAVS), the Disruption Mitigation System (DMS), the Glow Discharge Cleaning (GDC) system and the Plasma Position Reflectometry (PPR), an ex-vessel tenant installed in the U14 interspace region. Multi-physics analyses were performed for an in-vessel and exvessel component design integration following the ITER port integration requirements and the ITER guideline for Load Specification. Electromagnetic (EM), inertial and heating loads of the main U14 components under various conditions for the diagnostic shield module (DSM) and its internal shielding block attachment design have been summarized. The structural design of in-port components is based on an optimization of the EM load distribution to limit the load impact to the Diagnostic First Wall (DFW) and the tenant diagnostics, and to mitigate the effect of dynamic amplification from asymmetric plasma VDE (Vertical Displacement Event) inertial loads. The DSM needs to provide a sufficient stiffness for the protection of on-board diagnostics and structural integrity of the port integration under the design-driving EM and inertial loads. The in-port diagnostics and mounting supports, on the other hand, are designed to meet the remote handling requirement, while taking into account the thermal loads due to temperature gradient from nuclear heating, as well as matching the relative stiffness among the structural components within the port assembly. Progress on an integrated design and analysis is reported including a seismic analysis of the IS/PC region for extracting tenant interface loads. The design driving loads for tenant systems are presented for the attachment structure design as part of the PP engineering tasks.

Research paper thumbnail of EM Analysis of ITER Diagnostics Upper Port Plugs 14 and 11 During Plasma Disruptions

IEEE Transactions on Plasma Science, 2018

Research paper thumbnail of Selected Composites for High Field Magnets

MRS Proceedings, 2006

The national high magnetic field laboratory builds and uses various high field magnets for fundam... more The national high magnetic field laboratory builds and uses various high field magnets for fundamental research. In building high field magnets, a variety of high strength composites are required because of the Lorentz stresses generated by high field exceeding the strength of most of the materials, particular conductors. For example, a field of 60 T can generate a magnetic pressure that corresponds to a stress in the conductor of 1.5 GPa, which is at the limit of known conducting materials with conductivity higher than 70% International Annealed Copper Standard and sizes suitable for building high field magnets. The design of high field magnets is limited by these forces and, consequently, by the available materials. At the same time, the materials need to have excellent physical properties. For instance, the conductors need to have high electrical conductivity and high specific heat and the superconductors should have high critical current in field and low alternative current loss...

Research paper thumbnail of Resistive Solenoid Development at the NHMFL Based on Irregular Stacking Method

IEEE Transactions on Applied Superconductivity, 2012

ABSTRACT The National High Magnetic Field Laboratory (NHMFL) in Tallahassee, Florida designs, bui... more ABSTRACT The National High Magnetic Field Laboratory (NHMFL) in Tallahassee, Florida designs, builds and operates the world&#39;s highest field dc resistive magnets, providing fields up to 36 T in pure resistive systems and up to 45 T in resistive-superconducting hybrids. The NHMFL has several resistive solenoid magnet projects underway presently, including upgrading existing magnets, designing the conical insert for the Helmholtz Center Berlin (HZB), and designing insert coils of the Series-Connected-Hybrid (SCH) for NHMFL. In addition, building the 28 MW all resistive magnets will start in 2012. The method, called irregular stacking, successfully used in the upgrade of the existing magnets in 2009, will be employed in the new upgrades and the design of the new magnet system. In this paper, the progresses of each project are briefly summarized at first. The new technology of irregular stacking is then discussed in detail. In the last section, the application of the technology in future upgrades and the design of the magnets are present.

Research paper thumbnail of The Powered Scattering-Magnet Program at the NHMFL

IEEE Transactions on Applied Superconductivity, 2008

Research paper thumbnail of Recent Progress of the Series-Connected Hybrid Magnet Projects

IEEE Transactions on Applied Superconductivity, 2010

The National High Magnetic Field Laboratory (NHMFL) in Tallahassee, Florida has designed and is n... more The National High Magnetic Field Laboratory (NHMFL) in Tallahassee, Florida has designed and is now constructing two Series Connected Hybrid (SCH) magnets, each connecting a superconducting outsert coil and a resistive Florida Bitter insert coil electrically in series. The SCH to be installed at the NHMFL will produce 36 T and provide 1 ppm maximum field inhomogeneity over a 1 cm diameter spherical volume. The SCH to be installed at the Helmholtz Center Berlin (HZB) in combination with a neutron source will produce 25 T to 30 T depending on the resistive insert. The two magnets have a common design for their cable-in-conduit conductor (CICC) and superconducting outsert coils. The CICC outsert coil winding packs have an inner diameter of 0.6 m and contribute 13.1 T to the central field using three grades of CICC conductors. Each conductor grade carries 20 kA and employs the same type of Nb 3 Sn superconducting wire, but each grade contains different quantities of superconducting wires, different cabling patterns and different aspect ratios. The cryostats and resistive insert coils for the two magnets are different. This paper discusses the progress in CIC conductor and coil fabrication over the last year including specification, qualification and production activities for wire, cable, conductor and coil processing.

Research paper thumbnail of Cryostat Design for the NHMFL Series-Connected Hybrid

IEEE Transactions on Applied Superconductivity, 2011

The National High Magnetic Field Laboratory (NHMFL) is designing a series-connected hybrid magnet... more The National High Magnetic Field Laboratory (NHMFL) is designing a series-connected hybrid magnet, which has a 40 mm diameter vertical warm bore with a cylindrical profile. The magnet will generate a 36 T field with 13 MW power for a high homogeneity version (1 ppm homogeneity) or 40 T for a high field version. This hybrid shares the design of superconducting coil with another SCH designed for Berlin, Germany. The cryostat design is quite different however. In this paper the design of the NHMFL cryostat is presented. The main features are described at first followed by the discussion of the FEA models and results.

Research paper thumbnail of Design and Analysis Progress of ITER Diagnostic Equatorial Port #09

IEEE Transactions on Plasma Science, 2018

ITER is the world's largest fusion device currently under construction in the South of France wit... more ITER is the world's largest fusion device currently under construction in the South of France with >50 diagnostic systems to be installed inside the port plugs (PPs), the interspace (IS) or the port cell (PC) region of various diagnostic ports. The plasma facing Diagnostic First Wall (DFW) and its supporting diagnostic shield modules (DSM) are designed to protect frontend diagnostics from plasma neutron and plasma radiation while providing apertures for diagnostic access to the plasma. The design of ITER port plug structures (PPS) including the DFW and the DSM is largely driven by the electromagnetic (EM) loads included on the PP structural components during plasma major disruptions (MDs) and the vertical displacement events (VDEs). Unlike DFW and DSM, the design of diagnostic system, however, is likely driven by the steady-state thermal loads from plasma volumetric and surface heating and the dynamic response of the in-port components attached to the port-specific DSM or closure plate under transient loads induced on the Vacuum Vessel (VV) and the port extension during asymmetric VDEs. Three tenant diagnostic systems are integrated into the equatorial port 09 (E09). The toroidal interferometer / polarimeter, or TIP system, is installed in the left drawer (DSM3, left looking from plasma) for measuring the plasma density so to control the fuel input. The electron cyclotron emission (ECE) system is installed in the middle drawer (DSM2) to provide the high spatial and temporal resolution measurements of electron temperature evolution and the electron thermal transport inferences. The visible/infrared wide angle viewing system is installed in the right drawer (DSM1) to provide visible and infra-red viewing and temperature data of the first wall for its protection in support of machine operation. The port plug integration design and multi-physics analyses are performed following port integration requirements including the weight limit (45 tones total), shut down dose rate limits, the cooling / heating and structural integrity validation. Mass distribution for TIP and ECE DSMs has been optimized to minimize the total weight by a new design of the boron carbide (B4C) shielding pocket. The lightened DSM maintains its frontend load distribution and the structural stiffness with minimum impact to the DFW so to better protect on-board diagnostics; while still provides sufficient front end stiffness for its structural integrity as well as the diagnostics function requirements.

Research paper thumbnail of 3D Stress-Strain Model of the Nb<formula formulatype="inline"> <tex Notation="TeX">$_{3}$</tex></formula>Sn Wire

IEEE Transactions on Applied Superconductivity, 2011

ABSTRACT The performance of Nb3Sn multifilament wires is highly strain-sensitive. Since the strai... more ABSTRACT The performance of Nb3Sn multifilament wires is highly strain-sensitive. Since the strain in each individual Nb3Sn filament rather than the overall strain on the Nb3Sn wire influences the superconducting properties, it is very important to build a relationship between the internal strain in each Nb3Sn filament and external loads. In this study, a 3D model is developed to address the relationship. It is found that the geometry of the cross-section of the filaments plays an important role in the relationship between the stress and strain.