Maurizio Bagnasco - Academia.edu (original) (raw)

Papers by Maurizio Bagnasco

Research paper thumbnail of Analysis of thermal-hydraulic effects in the testing of the ITER poloidal field full size joint sample

The PF-FSJS is a full-size joint sample, based on the NbTi dual-channel cable-inconduit conductor... more The PF-FSJS is a full-size joint sample, based on the NbTi dual-channel cable-inconduit conductor (CICC) design currently foreseen for the International Thermonuclear Experimental Reactor (ITER) Poloidal Field coil system. It was tested during the summer of 2002 in the Sultan facility of CRPP at a background peak magnetic field of typically 6 T. It includes about 3 m of two jointed conductor sections, using different strands but with identical layout. The sample was cooled by supercritical helium at nominal 4.5-5.0 K and 0.9-1.0 MPa, in forced convection from the top to the bottom of the vertical configuration. A pulsed coil was used to test AC losses in the two legs resulting, above a certain input power threshold, in bundle helium backflow from the heated region. Here we study the thermal-hydraulics of the phenomenon with the M&M code, with particular emphasis on the effects of buoyancy on the helium dynamics, as well as on the thermal-hydraulic coupling between the wrapped bundles of strands in the annular cable region and the central cooling channel. Both issues are ITER relevant, as they affect the more general question of the heat removal capability of the helium in this type of conductors.

Research paper thumbnail of Successful development of a react and wind conductor for the ITER toroidial field coils

Research paper thumbnail of Thermal-hydraulic analysis of the EDIPO cool down

Research paper thumbnail of Multi-Solid Multi-Channel THELMA Analysis of Sudden Quench of ITER Superconducting NbTi Full-Size Short Samples

Research paper thumbnail of Cryogenic Test Results of the ITER TF Model Coil Test in TOSKA

The ITER Toroidal Field Model Coil (TFMC) was designed and manufactured by the European Home Team... more The ITER Toroidal Field Model Coil (TFMC) was designed and manufactured by the European Home Team in collaboration with European industry. The test in the TOSKA facility of the Forschungszentrum Karlsruhe was successfully performed in 2001 and 2002 and has confirmed that the used design and construction principles are applicable for the ITER TF coils. The TFMC was tested up

Research paper thumbnail of Qualification tests and facilities for ITER TF Superconductors

All the ITER superconductors are tested as short length samples in the SULTAN test facility at CR... more All the ITER superconductors are tested as short length samples in the SULTAN test facility at CRPP. Eighteen TF conductor samples with small layout variations were tested since February 2007 with the aim of verification of the design and qualification of the manufacturers. The sample assembly and the measurement techniques at CRPP are discussed. Starting in 2010, another test facility for ITER conductors, named EDIPO, will be operating at CRPP to share with SULTAN the load of the samples for the acceptance tests during the construction of ITER.

Research paper thumbnail of Results of conductor testing in SULTAN

In the last few years, the DC performance of a large number of sub-and full-size NbTi as well as ... more In the last few years, the DC performance of a large number of sub-and full-size NbTi as well as Nb 3 Sn cablein-conduit (CIC) conductors was tested in the SULTAN facility of CRPP. The "potential" DC performance of various CIC conductors was estimated from the measured strand data. In the present work, the DC performance of CIC conductors, measured in SULTAN, is compared with this "potential" DC performance. The DC performance of NbTi sub-and full size CIC conductors has been found to be in good agreement with the "potential" conductor performance. For Nb 3 Sn CIC conductors, the situation is more complex because of the strain sensitivity of the critical current. Evidence for strand damage, caused by the large Lorentz forces, has been found in Nb 3 Sn subsize conductors. Finally, a summary of the results of the tests of the ITER-TF Nb 3 Sn conductors is provided. Again the measured DC performance is compared to the "potential" performance.

Research paper thumbnail of Pressure drop measurements in Cable-In-Conduit Conductors (CICC’s) for an extended range of Reynolds number

Przeglad Elektrotechniczny

ABSTRACT

Research paper thumbnail of Thermal-Hydraulic Issues in the ITER Toroidal Field Model Coil (TFMC) Test and Analysis

The International Thermonuclear Experimental Reactor (ITER) Toroidal Field Model Coil (TFMC) was ... more The International Thermonuclear Experimental Reactor (ITER) Toroidal Field Model Coil (TFMC) was tested in the Toska facility of Forschungszentrum Karlsruhe during 2001 (standalone) and 2002 (in the background magnetic field of the LCT coil). The TFMC is a racetrack coil wound in five double pancakes on stainless steel radial plates using Nb3Sn dual-channel cable-in-conduit conductor (CICC) with a thin circular SS jacket. The coil was cooled by supercritical helium in forced convection at nominal 4.5 K and 0.5 MPa. Instrumentation, all outside the coil, included voltage taps, pressure and temperature sensors, as well as flow meters. Additionally, differential pressure drop measurement was available on the two pancakes DP1.1 and DP1.2, equipped with heaters.Two major thermal-hydraulic issues in the TFMC tests will be addressed here: 1) the pressure drop along heated pancakes and the comparison with friction factor correlations; 2) the quench initiation and propagation. Other thermal-...

Research paper thumbnail of Conceptual design and analysis of a cryogenic system for a new test facility for high temperature superconductor current leads (HTS CLs)

Przeglad Elektrotechniczny

In view of the R&D program on HTS CL at EPFL-CRPP PSI Villigen it is foreseen to extend the capab... more In view of the R&D program on HTS CL at EPFL-CRPP PSI Villigen it is foreseen to extend the capabilities of an existing facility (JORDI) in order to be able to perform tests of HTS CL in different conditions. The present work is focused on the conceptual design of the cryogenics needed for the facility upgrade considering the requirement of an as extended as possible range of operation. Two cooling options for the copper part of a CL are considered. The use of heat exchangers for the optimization of the cryogenic system is discussed and their size is assessed.

Research paper thumbnail of Cryogenic Test Results of the ITER TF Model Coil Test in TOSKA

The ITER Toroidal Field Model Coil (TFMC) was designed and manufactured by the European Home Team... more The ITER Toroidal Field Model Coil (TFMC) was designed and manufactured by the European Home Team in collaboration with European industry. The test in the TOSKA facility of the Forschungszentrum Karlsruhe was successfully performed in 2001 and 2002 and has confirmed that the used design and construction principles are applicable for the ITER TF coils. The TFMC was tested up

Research paper thumbnail of EU contribution to the test and analysis of the ITER poloidal field conductor insert and the central solenoid model coil

Superconductor Science and Technology, 2009

The PFCI is a single-layer solenoid wound from a 45 m long ITER-type NbTi dual-channel cable-in-c... more The PFCI is a single-layer solenoid wound from a 45 m long ITER-type NbTi dual-channel cable-in-conduit conductor, designed to be representative of the one currently proposed for the ITER PF1&6 coils. The PFCI, installed in the bore of the ITER central solenoid model coil (CSMC) at JAEA Naka, Japan, and well instrumented from both the thermal hydraulic and the electromagnetic points of view, has been successfully tested in June-August 2008. The test concentrated on DC performance (current sharing temperature and critical current measurements) and AC loss measurements. The results of the analysis of those measurements are reported in the paper, with particular attention to the comparison with the PFCI short sample, which was previously tested in the SULTAN facility. The evolution of the DC performance of the CSMC is also discussed.

Research paper thumbnail of Qualification tests and facilities for the ITER superconductors

Nuclear Fusion, 2009

All the ITER superconductors are tested as short length samples in the SULTAN test facility at CR... more All the ITER superconductors are tested as short length samples in the SULTAN test facility at CRPP. Eighteen TF conductor samples with small layout variations were tested since February 2007 with the aim of verification of the design and qualification of the manufacturers. The sample assembly and the measurement techniques at CRPP are discussed. Starting in 2010, another test facility

Research paper thumbnail of Operation and Test Results From the SULTAN Test Facility

IEEE Transactions on Applied Superconductivity, 2000

ABSTRACT In the period between August 2010 and August 2011 the SULTAN test facility has been cont... more ABSTRACT In the period between August 2010 and August 2011 the SULTAN test facility has been continuously operated, with over one dozen test campaigns. Among the ITER conductors, five Toroidal Field (TF) samples, two Central Solenoid (CS) samples and four NbTi samples for Poloidal Field (PF), Correction Coil and Main Busbar coming from Japan, Russia, Korea and China have been tested with duration of test campaign ranging from two to nine weeks each. Two non-ITER conductor samples are also tested in the same period, a high current NbTi cable-in-conduit (CICC) for the secondary winding of the EDIPO flux pump and a prototype high field conductor for the hybrid magnet of the Radboud University (NL).

Research paper thumbnail of <tex>$rm T_rm cs$</tex>Tests and Performance Assessment of the ITER Toroidal Field Model Coil (Phase II)

IEEE Transactions on Appiled Superconductivity, 2004

The tests of the Toroidal Field Model Coil (TFMC) were completed in 2002 in the TOSKA facility of... more The tests of the Toroidal Field Model Coil (TFMC) were completed in 2002 in the TOSKA facility of Forschungszentrum Karlsruhe, Germany. Operation reached a combined 80 kA in the TFMC and 16 kA in the LCT coil, resulting in a peak electromechanical load very close to that expected in the full-size ITER TF coils (800 kN/m). Here we concentrate on the measurements of the current sharing temperature (T cs ) of the TFMC conductor, possibly the highlight of the whole test campaign. These tests were performed by increasing in steps the helium inlet temperature T in in double pancake DP1, resulting in an increasing normal voltage V across the DP1.1 and DP1.2 conductors, and were repeated for several combinations of currents in the TFMC and in the LCT coil. The analysis of the V T in characteristic by means of the M&M code allows to self-consistently deriving an estimate of T cs , as well as an indirect assessment of the "average" strain state in the conductor. The TFMC isolated strand has also been very recently characterized at different applied uniaxial strain, and preliminary results indicate a stronger reduction of carrying capacity compared to the extrapolation from Summers scaling used in the analysis so far. As a consequence, the performance of the TFMC conductor, as preliminarily re-evaluated here, appears more in line with the strand performance than in previous analysis, although a BI-dependent "degradation" is still present.

Research paper thumbnail of Development of a React & Wind Conductor for the ITER Toroidal Field Coils

IEEE Transactions on Applied Superconductivity, 2000

ABSTRACT

Research paper thumbnail of Progress in the Integrated Simulation of Thermal-Hydraulic Operation of the ITER Magnet System

IEEE Transactions on Applied Superconductivity, 2000

A new integrated computer code is being developed for the simulations of the overall behavior of ... more A new integrated computer code is being developed for the simulations of the overall behavior of the ITER magnet cryo-system. The existing THEA, FLOWER and POWER codes, assembled as modules of a computational environment (SuperMagnet) have been upgraded to perform global simulations of the cooling circuit for the ITER magnet system. The thermal coupling resulting from the generic geometric configurations has been implemented to realize quasi-three-dimensional simulations of the winding pack. In this paper we present details on the model.

Research paper thumbnail of Retest of the TFAS1 sample with solder filled extremities

ABSTRACT TFAS1 (toroidal field advanced strand) sample is composed of two cable-in-conduit conduc... more ABSTRACT TFAS1 (toroidal field advanced strand) sample is composed of two cable-in-conduit conductors intended to be used in ITER toroidal field coils. This sample was tested in the SULTAN facility in order to benchmark the performance in years 2005-2006. An early voltage evolution was observed in both conductors during current ramp up, which makes it difficult to assess correctly the conductor performance. In order to improve the voltage behavior, the two terminations and two halves of the joint were filled by solder at CRPP with the aim to achieve a more uniform current distribution in the conductors. Thereafter, the TFAS1 sample was retested in the SULTAN facility. The retest revealed an unexpected increase of resistance after solder filling at the conductor extremities. As a consequence the voltage slope did not disappear, and further reduction of conductor performance was observed. The results of the retest of the TFAS1 sample with solder filled extremities are presented and discussed in this paper.

Research paper thumbnail of Status Report of the SULTAN Test Facility

IEEE Transactions on Applied Superconductivity, 2000

One year of operation and test activity of the SULTAN test facility at CRPP-Villigen, from Octobe... more One year of operation and test activity of the SULTAN test facility at CRPP-Villigen, from October 2008 to October 2009 is reviewed. The main improvements of the facility include a new control system for the cryo-plant and a new electric motor for the helium compressor. The range of operation for the SULTAN samples has been improved in terms of cyclic

Research paper thumbnail of Helium Flow and Temperature Distribution in a Heated Dual-Channel CICC Sample for ITER

IEEE Transactions on Applied Superconductivity, 2000

A spare, 3.5 m long dual-channel cable-in-conduit conductor (CICC) section, made according to the... more A spare, 3.5 m long dual-channel cable-in-conduit conductor (CICC) section, made according to the most recent ITER toroidal-field coil design, allowed conducting dedicated thermo-hydraulic experiments in the SULTAN test facility. The sample was heated by eddy-current losses induced in the strands by an applied AC magnetic field as well as by strip heaters mounted on the outside of the conductor jacket. Temperature sensors mounted on the jacket surface, in the central channel and at different radii in the annular region revealed a detailed picture of the temperature distribution at different mass flow rates and heat deposition modes. A clear phenomenological description of the temperature deviations from the one-dimensional expectation emerged during the experiments. The measurement of the flow velocities in the central channel and in the annular region under several heat-load conditions led to further insights.

Research paper thumbnail of Analysis of thermal-hydraulic effects in the testing of the ITER poloidal field full size joint sample

The PF-FSJS is a full-size joint sample, based on the NbTi dual-channel cable-inconduit conductor... more The PF-FSJS is a full-size joint sample, based on the NbTi dual-channel cable-inconduit conductor (CICC) design currently foreseen for the International Thermonuclear Experimental Reactor (ITER) Poloidal Field coil system. It was tested during the summer of 2002 in the Sultan facility of CRPP at a background peak magnetic field of typically 6 T. It includes about 3 m of two jointed conductor sections, using different strands but with identical layout. The sample was cooled by supercritical helium at nominal 4.5-5.0 K and 0.9-1.0 MPa, in forced convection from the top to the bottom of the vertical configuration. A pulsed coil was used to test AC losses in the two legs resulting, above a certain input power threshold, in bundle helium backflow from the heated region. Here we study the thermal-hydraulics of the phenomenon with the M&M code, with particular emphasis on the effects of buoyancy on the helium dynamics, as well as on the thermal-hydraulic coupling between the wrapped bundles of strands in the annular cable region and the central cooling channel. Both issues are ITER relevant, as they affect the more general question of the heat removal capability of the helium in this type of conductors.

Research paper thumbnail of Successful development of a react and wind conductor for the ITER toroidial field coils

Research paper thumbnail of Thermal-hydraulic analysis of the EDIPO cool down

Research paper thumbnail of Multi-Solid Multi-Channel THELMA Analysis of Sudden Quench of ITER Superconducting NbTi Full-Size Short Samples

Research paper thumbnail of Cryogenic Test Results of the ITER TF Model Coil Test in TOSKA

The ITER Toroidal Field Model Coil (TFMC) was designed and manufactured by the European Home Team... more The ITER Toroidal Field Model Coil (TFMC) was designed and manufactured by the European Home Team in collaboration with European industry. The test in the TOSKA facility of the Forschungszentrum Karlsruhe was successfully performed in 2001 and 2002 and has confirmed that the used design and construction principles are applicable for the ITER TF coils. The TFMC was tested up

Research paper thumbnail of Qualification tests and facilities for ITER TF Superconductors

All the ITER superconductors are tested as short length samples in the SULTAN test facility at CR... more All the ITER superconductors are tested as short length samples in the SULTAN test facility at CRPP. Eighteen TF conductor samples with small layout variations were tested since February 2007 with the aim of verification of the design and qualification of the manufacturers. The sample assembly and the measurement techniques at CRPP are discussed. Starting in 2010, another test facility for ITER conductors, named EDIPO, will be operating at CRPP to share with SULTAN the load of the samples for the acceptance tests during the construction of ITER.

Research paper thumbnail of Results of conductor testing in SULTAN

In the last few years, the DC performance of a large number of sub-and full-size NbTi as well as ... more In the last few years, the DC performance of a large number of sub-and full-size NbTi as well as Nb 3 Sn cablein-conduit (CIC) conductors was tested in the SULTAN facility of CRPP. The "potential" DC performance of various CIC conductors was estimated from the measured strand data. In the present work, the DC performance of CIC conductors, measured in SULTAN, is compared with this "potential" DC performance. The DC performance of NbTi sub-and full size CIC conductors has been found to be in good agreement with the "potential" conductor performance. For Nb 3 Sn CIC conductors, the situation is more complex because of the strain sensitivity of the critical current. Evidence for strand damage, caused by the large Lorentz forces, has been found in Nb 3 Sn subsize conductors. Finally, a summary of the results of the tests of the ITER-TF Nb 3 Sn conductors is provided. Again the measured DC performance is compared to the "potential" performance.

Research paper thumbnail of Pressure drop measurements in Cable-In-Conduit Conductors (CICC’s) for an extended range of Reynolds number

Przeglad Elektrotechniczny

ABSTRACT

Research paper thumbnail of Thermal-Hydraulic Issues in the ITER Toroidal Field Model Coil (TFMC) Test and Analysis

The International Thermonuclear Experimental Reactor (ITER) Toroidal Field Model Coil (TFMC) was ... more The International Thermonuclear Experimental Reactor (ITER) Toroidal Field Model Coil (TFMC) was tested in the Toska facility of Forschungszentrum Karlsruhe during 2001 (standalone) and 2002 (in the background magnetic field of the LCT coil). The TFMC is a racetrack coil wound in five double pancakes on stainless steel radial plates using Nb3Sn dual-channel cable-in-conduit conductor (CICC) with a thin circular SS jacket. The coil was cooled by supercritical helium in forced convection at nominal 4.5 K and 0.5 MPa. Instrumentation, all outside the coil, included voltage taps, pressure and temperature sensors, as well as flow meters. Additionally, differential pressure drop measurement was available on the two pancakes DP1.1 and DP1.2, equipped with heaters.Two major thermal-hydraulic issues in the TFMC tests will be addressed here: 1) the pressure drop along heated pancakes and the comparison with friction factor correlations; 2) the quench initiation and propagation. Other thermal-...

Research paper thumbnail of Conceptual design and analysis of a cryogenic system for a new test facility for high temperature superconductor current leads (HTS CLs)

Przeglad Elektrotechniczny

In view of the R&D program on HTS CL at EPFL-CRPP PSI Villigen it is foreseen to extend the capab... more In view of the R&D program on HTS CL at EPFL-CRPP PSI Villigen it is foreseen to extend the capabilities of an existing facility (JORDI) in order to be able to perform tests of HTS CL in different conditions. The present work is focused on the conceptual design of the cryogenics needed for the facility upgrade considering the requirement of an as extended as possible range of operation. Two cooling options for the copper part of a CL are considered. The use of heat exchangers for the optimization of the cryogenic system is discussed and their size is assessed.

Research paper thumbnail of Cryogenic Test Results of the ITER TF Model Coil Test in TOSKA

The ITER Toroidal Field Model Coil (TFMC) was designed and manufactured by the European Home Team... more The ITER Toroidal Field Model Coil (TFMC) was designed and manufactured by the European Home Team in collaboration with European industry. The test in the TOSKA facility of the Forschungszentrum Karlsruhe was successfully performed in 2001 and 2002 and has confirmed that the used design and construction principles are applicable for the ITER TF coils. The TFMC was tested up

Research paper thumbnail of EU contribution to the test and analysis of the ITER poloidal field conductor insert and the central solenoid model coil

Superconductor Science and Technology, 2009

The PFCI is a single-layer solenoid wound from a 45 m long ITER-type NbTi dual-channel cable-in-c... more The PFCI is a single-layer solenoid wound from a 45 m long ITER-type NbTi dual-channel cable-in-conduit conductor, designed to be representative of the one currently proposed for the ITER PF1&6 coils. The PFCI, installed in the bore of the ITER central solenoid model coil (CSMC) at JAEA Naka, Japan, and well instrumented from both the thermal hydraulic and the electromagnetic points of view, has been successfully tested in June-August 2008. The test concentrated on DC performance (current sharing temperature and critical current measurements) and AC loss measurements. The results of the analysis of those measurements are reported in the paper, with particular attention to the comparison with the PFCI short sample, which was previously tested in the SULTAN facility. The evolution of the DC performance of the CSMC is also discussed.

Research paper thumbnail of Qualification tests and facilities for the ITER superconductors

Nuclear Fusion, 2009

All the ITER superconductors are tested as short length samples in the SULTAN test facility at CR... more All the ITER superconductors are tested as short length samples in the SULTAN test facility at CRPP. Eighteen TF conductor samples with small layout variations were tested since February 2007 with the aim of verification of the design and qualification of the manufacturers. The sample assembly and the measurement techniques at CRPP are discussed. Starting in 2010, another test facility

Research paper thumbnail of Operation and Test Results From the SULTAN Test Facility

IEEE Transactions on Applied Superconductivity, 2000

ABSTRACT In the period between August 2010 and August 2011 the SULTAN test facility has been cont... more ABSTRACT In the period between August 2010 and August 2011 the SULTAN test facility has been continuously operated, with over one dozen test campaigns. Among the ITER conductors, five Toroidal Field (TF) samples, two Central Solenoid (CS) samples and four NbTi samples for Poloidal Field (PF), Correction Coil and Main Busbar coming from Japan, Russia, Korea and China have been tested with duration of test campaign ranging from two to nine weeks each. Two non-ITER conductor samples are also tested in the same period, a high current NbTi cable-in-conduit (CICC) for the secondary winding of the EDIPO flux pump and a prototype high field conductor for the hybrid magnet of the Radboud University (NL).

Research paper thumbnail of <tex>$rm T_rm cs$</tex>Tests and Performance Assessment of the ITER Toroidal Field Model Coil (Phase II)

IEEE Transactions on Appiled Superconductivity, 2004

The tests of the Toroidal Field Model Coil (TFMC) were completed in 2002 in the TOSKA facility of... more The tests of the Toroidal Field Model Coil (TFMC) were completed in 2002 in the TOSKA facility of Forschungszentrum Karlsruhe, Germany. Operation reached a combined 80 kA in the TFMC and 16 kA in the LCT coil, resulting in a peak electromechanical load very close to that expected in the full-size ITER TF coils (800 kN/m). Here we concentrate on the measurements of the current sharing temperature (T cs ) of the TFMC conductor, possibly the highlight of the whole test campaign. These tests were performed by increasing in steps the helium inlet temperature T in in double pancake DP1, resulting in an increasing normal voltage V across the DP1.1 and DP1.2 conductors, and were repeated for several combinations of currents in the TFMC and in the LCT coil. The analysis of the V T in characteristic by means of the M&M code allows to self-consistently deriving an estimate of T cs , as well as an indirect assessment of the "average" strain state in the conductor. The TFMC isolated strand has also been very recently characterized at different applied uniaxial strain, and preliminary results indicate a stronger reduction of carrying capacity compared to the extrapolation from Summers scaling used in the analysis so far. As a consequence, the performance of the TFMC conductor, as preliminarily re-evaluated here, appears more in line with the strand performance than in previous analysis, although a BI-dependent "degradation" is still present.

Research paper thumbnail of Development of a React & Wind Conductor for the ITER Toroidal Field Coils

IEEE Transactions on Applied Superconductivity, 2000

ABSTRACT

Research paper thumbnail of Progress in the Integrated Simulation of Thermal-Hydraulic Operation of the ITER Magnet System

IEEE Transactions on Applied Superconductivity, 2000

A new integrated computer code is being developed for the simulations of the overall behavior of ... more A new integrated computer code is being developed for the simulations of the overall behavior of the ITER magnet cryo-system. The existing THEA, FLOWER and POWER codes, assembled as modules of a computational environment (SuperMagnet) have been upgraded to perform global simulations of the cooling circuit for the ITER magnet system. The thermal coupling resulting from the generic geometric configurations has been implemented to realize quasi-three-dimensional simulations of the winding pack. In this paper we present details on the model.

Research paper thumbnail of Retest of the TFAS1 sample with solder filled extremities

ABSTRACT TFAS1 (toroidal field advanced strand) sample is composed of two cable-in-conduit conduc... more ABSTRACT TFAS1 (toroidal field advanced strand) sample is composed of two cable-in-conduit conductors intended to be used in ITER toroidal field coils. This sample was tested in the SULTAN facility in order to benchmark the performance in years 2005-2006. An early voltage evolution was observed in both conductors during current ramp up, which makes it difficult to assess correctly the conductor performance. In order to improve the voltage behavior, the two terminations and two halves of the joint were filled by solder at CRPP with the aim to achieve a more uniform current distribution in the conductors. Thereafter, the TFAS1 sample was retested in the SULTAN facility. The retest revealed an unexpected increase of resistance after solder filling at the conductor extremities. As a consequence the voltage slope did not disappear, and further reduction of conductor performance was observed. The results of the retest of the TFAS1 sample with solder filled extremities are presented and discussed in this paper.

Research paper thumbnail of Status Report of the SULTAN Test Facility

IEEE Transactions on Applied Superconductivity, 2000

One year of operation and test activity of the SULTAN test facility at CRPP-Villigen, from Octobe... more One year of operation and test activity of the SULTAN test facility at CRPP-Villigen, from October 2008 to October 2009 is reviewed. The main improvements of the facility include a new control system for the cryo-plant and a new electric motor for the helium compressor. The range of operation for the SULTAN samples has been improved in terms of cyclic

Research paper thumbnail of Helium Flow and Temperature Distribution in a Heated Dual-Channel CICC Sample for ITER

IEEE Transactions on Applied Superconductivity, 2000

A spare, 3.5 m long dual-channel cable-in-conduit conductor (CICC) section, made according to the... more A spare, 3.5 m long dual-channel cable-in-conduit conductor (CICC) section, made according to the most recent ITER toroidal-field coil design, allowed conducting dedicated thermo-hydraulic experiments in the SULTAN test facility. The sample was heated by eddy-current losses induced in the strands by an applied AC magnetic field as well as by strip heaters mounted on the outside of the conductor jacket. Temperature sensors mounted on the jacket surface, in the central channel and at different radii in the annular region revealed a detailed picture of the temperature distribution at different mass flow rates and heat deposition modes. A clear phenomenological description of the temperature deviations from the one-dimensional expectation emerged during the experiments. The measurement of the flow velocities in the central channel and in the annular region under several heat-load conditions led to further insights.