Rafael Iturbe - Academia.edu (original) (raw)

Papers by Rafael Iturbe

Dyna, Mar 1, 2007

The creation of new particles constituent of the matter is obtained in the collision of other par... more The creation of new particles constituent of the matter is obtained in the collision of other particles accelerated to great energies: greater the energy, deeper is the knowledge. The new LHC accelerator of CERN, with the greater energy ever employed, will let to discover further horizons.

A 600 A current lead using 2212 BSCCO bulk material is now under construction and will be soon de... more A 600 A current lead using 2212 BSCCO bulk material is now under construction and will be soon delivered to CERN. Present paper describes the main steps of its design and fabrication, including the two main parts in which it is divided, the superconducting module with the BSCCO rods and the conventional resistive part. An important role in this design was played by previous experimental measurements on subassemblies, which are also described along the paper. (5 refs)

Journal of Physics: Conference Series, 2014

ABSTRACT Although renewable sector has started to take advantage of the offshore wind energy rece... more ABSTRACT Although renewable sector has started to take advantage of the offshore wind energy recently, the development is very intense. Turbines reliability, size, and cost are key aspects for the wind industry, especially in marine locations. A superconducting generator will allow a significant reduction in terms of weight and size, but cost and reliability are two aspects to deal with. MgB2 wire is presented as one promising option to be used in superconducting coils for wind generators. This work shows the experimental results in first cryogen-free MgB2 prototype coils, designed according to specific requirements of TECNALIA's wind generator concept.

IEEE Transactions on Appiled Superconductivity, 1997

This paper describes the design and manufacturing of a 25 kJ superconducting coil as well as its ... more This paper describes the design and manufacturing of a 25 kJ superconducting coil as well as its cryostat and magnet support, including current leads and cryogenic services, for an SMES. The coil design is based on a minimum volume criteria. The cryostat is designed for 60 1 of liquid helium, and the magnet support with current leads optimised for 150 A. Using numerical modelling the total heat transfer into the liquid is calculated and minimised. The manufacturing of both components is also presented, as well as the complete system operation. Finally the papeir presents the power converter topology that is controlled in optimal PWM mode with a low switching frequency. In order to compensate different power oscillations the power converter interchanges fastly adjustable and uncoupled levells of real and reactive power.

Dyna, 2005

En el mes de abril de 2007 esta prevista la entrada en funcionamiento del LHC (Large Hadron * Col... more En el mes de abril de 2007 esta prevista la entrada en funcionamiento del LHC (Large Hadron * Collider), la mas moderna y potente maquina disenada para profundizar en el conocimiento intimo de la materia y de las leyes por las que se rige el Universo. La industria europea esta construyendo en estos momentos los diversos componentes, para lo que tiene que enfrentarse a desafios tecnologicos desconocidos hasta la fecha. Introduccion Hace pocos meses se han celebrado los actos de conmemoracion del 50 aniversario de la constitucion del CERN: el acto oficial tuvo lugar el 19 de octubre de 2004 en la sede de Meyrin (Ginebra), con la asistencia de jefes de estado como Jacques Chirac y Joseph Deiss, presidentes de Francia y Suiza, y el rey Juan Carlos de Espana, asi como centenares de cientificos e ingenieros de muchos paises, que elogiaron la labor desarrollada en el avance de la ciencia y en el fomento de la colaboracion internacional entre cientificos. El tema mas comun en las conferenci...

In the automotive industry, increasing ecological concerns and demands for higher performance hav... more In the automotive industry, increasing ecological concerns and demands for higher performance have become lightweight construction a key aspect. Due to the gradual introduction of high strength materials on the one side, and greater consideration with regard to continuous manufacturing technologies on the other side, it is possible nowadays to address the demands that structural and complex automotive parts have to face, from the standpoint of lightweight manufacturing. Thickness, shape and impact conditions constitute the main aspects to consider for such parts and shape conditions in particular require from complex, costly and lengthy procedures, especially when discontinuous forming operations such as stamping and hydro forming procedures are selected. However, continuous forming operations like Roll Forming (RF) can prove to be advantageous and suited for scalable parts (e.g in length) and at the same time be economically reasonable. RF lines as well generally incorporate additi...

IEEE Transactions on Appiled Superconductivity, 2001

This paper describes the design and fabrication of four sets of HTc 600 A current leads manufactu... more This paper describes the design and fabrication of four sets of HTc 600 A current leads manufactured by ANTEC in collaboration with three more Institutes to test the feasibility of industrial fabrication of these units. This development has been made in the framework of a CERN programme to build low thermal losses leads for the correction magnets of the LHC. Tests performed at the manufacturer installations are also presented.

IEEE Transactions on Applied Superconductivity, 2014

ABSTRACT The procurement of 103 superconducting magnet packages is part of the Spanish in-kind co... more ABSTRACT The procurement of 103 superconducting magnet packages is part of the Spanish in-kind contribution to the European X-FEL. Each package consists of a main superferric quadrupole and two steerers, vertical and horizontal, fed by conduction-cooled current leads and enclosed in a stainless steel vessel. The operation temperature is 2 K, as they are embedded in a superfluid helium bath. The magnetic and mechanical designs are published elsewhere. The magnets are being produced in the Spanish company ANTEC, while the vessels are fabricated by another Spanish company, Trinos Vacuum-Projects, which is also responsible for the integration, under the supervision of CIEMAT. The helium vessel manufacturer needs to accomplish the requirements given by the European Pressure Equipment Directive, namely PED 97/23/EC. This paper describes the series fabrication techniques, the production follow-up, the quality assurance, and the magnet testing at the manufacturer site. Cold tests are realized at DESY premises. The main problems found during the fabrication of the first half of the series are also reported: 1) the reproducibility of the quadrupole coil dimensions; 2) the accuracy of the beam position monitor housing after final welding of the vessel; and 3) the minimization of the magnetization effects on the transfer function of the magnets.

IEEE Transactions on Appiled Superconductivity, 2002

An international collaboration at DESY is currently studying the possibilities of a new type of p... more An international collaboration at DESY is currently studying the possibilities of a new type of particle accelerator: the superconducting linear collider. Developed under the project name TESLA, which stands for TeV Energy Superconducting Linear Accelerator, the facility would be placed in a 33-km long tunnel and would work at the energy range of 0.5 to 0.8 TeV. This paper is

IEEE Transactions on Appiled Superconductivity, 1995

This paper describes the design and construction of a 12T NbSSn-NbTi magnet for testing high-Tc s... more This paper describes the design and construction of a 12T NbSSn-NbTi magnet for testing high-Tc superconductors. The magnet is a first prototype of a future and bigger test station and it has been made to validate the main concepts as well as the manufacturing techniques. The first part describes the magnetic and mechanical design of the magnet with special attention to the computation of magnetic couplings, mechanical stresses and quench calculations, while the second part analyzes the construction of the magnet and the first results.

The Medium Energy Beam Transport line MEBT [1, 2] is currently being installed on the LIPAC accel... more The Medium Energy Beam Transport line MEBT [1, 2] is currently being installed on the LIPAC accelerator [3] and has among its components, five quadrupole and steerer magnets which were recently manufactured and tested. Given the compactness of the MEBT line, each magnet combines, in a common yoke, a strong quadrupole field with a minor horizontal and vertical steering. In this way, each yoke integrates four water-cooled coils (quadrupole coils) and eight air-cooled coils (steerer coils) made of copper wires. The magnetic design of the five combined magnets was done by CIEMAT [4] and the manufacturing and testing (excluding magnetic measurements) were carried out by the Spanish company Antec SA. With respect to the engineering design, it was mainly done by Antec SA but reviewed and agreed with CIEMAT. This paper focuses on the technical aspects considered during the manufacturing and assembly of the MEBT magnets. Some details about the factory acceptance tests that were carried out b...

With the main aim of a compact machine for 18F and 11C radioisotope production, AMIT cyclotron re... more With the main aim of a compact machine for 18F and 11C radioisotope production, AMIT cyclotron relies on a superconducting 4T magnet with an internal cold cathode PIG ion source for Hproduction. Given the limited access to the ion source in the cyclotron as well the reduced number of beam diagnostics, an experimental facility was proposed for the commissioning of such ion source. The versatility of this test bench, which includes a movable puller, gives us the opportunity to validate and characterize the ion source behavior as well as to optimize the Hproduction. In a first stage, the discharge characteristics of the ion source has been studied in the CIEMAT IST facilities.

Información del artículo Transformación de aceros de alta resistencia mediante impulsos electroma... more Información del artículo Transformación de aceros de alta resistencia mediante impulsos electromagnéticos.

IEEE Transactions on Applied Superconductivity, 2018

A superconducting magnet able to provide the required field of 4 T has been developed for a compa... more A superconducting magnet able to provide the required field of 4 T has been developed for a compact cyclotron to produce radioisotopes for medical imaging, in the framework of the AMIT project. It consists of two coils in Helmholtz confi-guration, embedded in a stainless steel casing to hold the Lorentz forces. The cooling scheme is based on a low pressure forced internal flow of two-phase liquid-vapour helium through a narrow channel machined in that casing. This paper reports on the cooling tests and the preliminary magnetic measurements of the magnet. Regarding cooling tests, liquid Helium from a Dewar has been used first to train the magnet and to estimate the thermal losses. Later, refrigeration will be accomplished from a stand-alone cryogenic supply system that would allow a user-friendly operation of the cyclotron, without external supply of cryogens. Regarding magnetic measurements, a custom magnetic measurement bench developed in collaboration with ALBA/CELLS, has been use...

IEEE Transactions on Applied Superconductivity, 2016

SAE Technical Paper Series, 2009

IEEE Transactions on Applied Superconductivity, 2016

Dyna, Mar 1, 2007

The creation of new particles constituent of the matter is obtained in the collision of other par... more The creation of new particles constituent of the matter is obtained in the collision of other particles accelerated to great energies: greater the energy, deeper is the knowledge. The new LHC accelerator of CERN, with the greater energy ever employed, will let to discover further horizons.

A 600 A current lead using 2212 BSCCO bulk material is now under construction and will be soon de... more A 600 A current lead using 2212 BSCCO bulk material is now under construction and will be soon delivered to CERN. Present paper describes the main steps of its design and fabrication, including the two main parts in which it is divided, the superconducting module with the BSCCO rods and the conventional resistive part. An important role in this design was played by previous experimental measurements on subassemblies, which are also described along the paper. (5 refs)

Journal of Physics: Conference Series, 2014

ABSTRACT Although renewable sector has started to take advantage of the offshore wind energy rece... more ABSTRACT Although renewable sector has started to take advantage of the offshore wind energy recently, the development is very intense. Turbines reliability, size, and cost are key aspects for the wind industry, especially in marine locations. A superconducting generator will allow a significant reduction in terms of weight and size, but cost and reliability are two aspects to deal with. MgB2 wire is presented as one promising option to be used in superconducting coils for wind generators. This work shows the experimental results in first cryogen-free MgB2 prototype coils, designed according to specific requirements of TECNALIA's wind generator concept.

IEEE Transactions on Appiled Superconductivity, 1997

This paper describes the design and manufacturing of a 25 kJ superconducting coil as well as its ... more This paper describes the design and manufacturing of a 25 kJ superconducting coil as well as its cryostat and magnet support, including current leads and cryogenic services, for an SMES. The coil design is based on a minimum volume criteria. The cryostat is designed for 60 1 of liquid helium, and the magnet support with current leads optimised for 150 A. Using numerical modelling the total heat transfer into the liquid is calculated and minimised. The manufacturing of both components is also presented, as well as the complete system operation. Finally the papeir presents the power converter topology that is controlled in optimal PWM mode with a low switching frequency. In order to compensate different power oscillations the power converter interchanges fastly adjustable and uncoupled levells of real and reactive power.

Dyna, 2005

En el mes de abril de 2007 esta prevista la entrada en funcionamiento del LHC (Large Hadron * Col... more En el mes de abril de 2007 esta prevista la entrada en funcionamiento del LHC (Large Hadron * Collider), la mas moderna y potente maquina disenada para profundizar en el conocimiento intimo de la materia y de las leyes por las que se rige el Universo. La industria europea esta construyendo en estos momentos los diversos componentes, para lo que tiene que enfrentarse a desafios tecnologicos desconocidos hasta la fecha. Introduccion Hace pocos meses se han celebrado los actos de conmemoracion del 50 aniversario de la constitucion del CERN: el acto oficial tuvo lugar el 19 de octubre de 2004 en la sede de Meyrin (Ginebra), con la asistencia de jefes de estado como Jacques Chirac y Joseph Deiss, presidentes de Francia y Suiza, y el rey Juan Carlos de Espana, asi como centenares de cientificos e ingenieros de muchos paises, que elogiaron la labor desarrollada en el avance de la ciencia y en el fomento de la colaboracion internacional entre cientificos. El tema mas comun en las conferenci...

In the automotive industry, increasing ecological concerns and demands for higher performance hav... more In the automotive industry, increasing ecological concerns and demands for higher performance have become lightweight construction a key aspect. Due to the gradual introduction of high strength materials on the one side, and greater consideration with regard to continuous manufacturing technologies on the other side, it is possible nowadays to address the demands that structural and complex automotive parts have to face, from the standpoint of lightweight manufacturing. Thickness, shape and impact conditions constitute the main aspects to consider for such parts and shape conditions in particular require from complex, costly and lengthy procedures, especially when discontinuous forming operations such as stamping and hydro forming procedures are selected. However, continuous forming operations like Roll Forming (RF) can prove to be advantageous and suited for scalable parts (e.g in length) and at the same time be economically reasonable. RF lines as well generally incorporate additi...

IEEE Transactions on Appiled Superconductivity, 2001

This paper describes the design and fabrication of four sets of HTc 600 A current leads manufactu... more This paper describes the design and fabrication of four sets of HTc 600 A current leads manufactured by ANTEC in collaboration with three more Institutes to test the feasibility of industrial fabrication of these units. This development has been made in the framework of a CERN programme to build low thermal losses leads for the correction magnets of the LHC. Tests performed at the manufacturer installations are also presented.

IEEE Transactions on Applied Superconductivity, 2014

ABSTRACT The procurement of 103 superconducting magnet packages is part of the Spanish in-kind co... more ABSTRACT The procurement of 103 superconducting magnet packages is part of the Spanish in-kind contribution to the European X-FEL. Each package consists of a main superferric quadrupole and two steerers, vertical and horizontal, fed by conduction-cooled current leads and enclosed in a stainless steel vessel. The operation temperature is 2 K, as they are embedded in a superfluid helium bath. The magnetic and mechanical designs are published elsewhere. The magnets are being produced in the Spanish company ANTEC, while the vessels are fabricated by another Spanish company, Trinos Vacuum-Projects, which is also responsible for the integration, under the supervision of CIEMAT. The helium vessel manufacturer needs to accomplish the requirements given by the European Pressure Equipment Directive, namely PED 97/23/EC. This paper describes the series fabrication techniques, the production follow-up, the quality assurance, and the magnet testing at the manufacturer site. Cold tests are realized at DESY premises. The main problems found during the fabrication of the first half of the series are also reported: 1) the reproducibility of the quadrupole coil dimensions; 2) the accuracy of the beam position monitor housing after final welding of the vessel; and 3) the minimization of the magnetization effects on the transfer function of the magnets.

IEEE Transactions on Appiled Superconductivity, 2002

An international collaboration at DESY is currently studying the possibilities of a new type of p... more An international collaboration at DESY is currently studying the possibilities of a new type of particle accelerator: the superconducting linear collider. Developed under the project name TESLA, which stands for TeV Energy Superconducting Linear Accelerator, the facility would be placed in a 33-km long tunnel and would work at the energy range of 0.5 to 0.8 TeV. This paper is

IEEE Transactions on Appiled Superconductivity, 1995

This paper describes the design and construction of a 12T NbSSn-NbTi magnet for testing high-Tc s... more This paper describes the design and construction of a 12T NbSSn-NbTi magnet for testing high-Tc superconductors. The magnet is a first prototype of a future and bigger test station and it has been made to validate the main concepts as well as the manufacturing techniques. The first part describes the magnetic and mechanical design of the magnet with special attention to the computation of magnetic couplings, mechanical stresses and quench calculations, while the second part analyzes the construction of the magnet and the first results.

The Medium Energy Beam Transport line MEBT [1, 2] is currently being installed on the LIPAC accel... more The Medium Energy Beam Transport line MEBT [1, 2] is currently being installed on the LIPAC accelerator [3] and has among its components, five quadrupole and steerer magnets which were recently manufactured and tested. Given the compactness of the MEBT line, each magnet combines, in a common yoke, a strong quadrupole field with a minor horizontal and vertical steering. In this way, each yoke integrates four water-cooled coils (quadrupole coils) and eight air-cooled coils (steerer coils) made of copper wires. The magnetic design of the five combined magnets was done by CIEMAT [4] and the manufacturing and testing (excluding magnetic measurements) were carried out by the Spanish company Antec SA. With respect to the engineering design, it was mainly done by Antec SA but reviewed and agreed with CIEMAT. This paper focuses on the technical aspects considered during the manufacturing and assembly of the MEBT magnets. Some details about the factory acceptance tests that were carried out b...

With the main aim of a compact machine for 18F and 11C radioisotope production, AMIT cyclotron re... more With the main aim of a compact machine for 18F and 11C radioisotope production, AMIT cyclotron relies on a superconducting 4T magnet with an internal cold cathode PIG ion source for Hproduction. Given the limited access to the ion source in the cyclotron as well the reduced number of beam diagnostics, an experimental facility was proposed for the commissioning of such ion source. The versatility of this test bench, which includes a movable puller, gives us the opportunity to validate and characterize the ion source behavior as well as to optimize the Hproduction. In a first stage, the discharge characteristics of the ion source has been studied in the CIEMAT IST facilities.

Información del artículo Transformación de aceros de alta resistencia mediante impulsos electroma... more Información del artículo Transformación de aceros de alta resistencia mediante impulsos electromagnéticos.

IEEE Transactions on Applied Superconductivity, 2018

A superconducting magnet able to provide the required field of 4 T has been developed for a compa... more A superconducting magnet able to provide the required field of 4 T has been developed for a compact cyclotron to produce radioisotopes for medical imaging, in the framework of the AMIT project. It consists of two coils in Helmholtz confi-guration, embedded in a stainless steel casing to hold the Lorentz forces. The cooling scheme is based on a low pressure forced internal flow of two-phase liquid-vapour helium through a narrow channel machined in that casing. This paper reports on the cooling tests and the preliminary magnetic measurements of the magnet. Regarding cooling tests, liquid Helium from a Dewar has been used first to train the magnet and to estimate the thermal losses. Later, refrigeration will be accomplished from a stand-alone cryogenic supply system that would allow a user-friendly operation of the cyclotron, without external supply of cryogens. Regarding magnetic measurements, a custom magnetic measurement bench developed in collaboration with ALBA/CELLS, has been use...

IEEE Transactions on Applied Superconductivity, 2016

SAE Technical Paper Series, 2009

IEEE Transactions on Applied Superconductivity, 2016