A5078530021- Superconducting Materials and Applications
- Particle Accelerators and Free-Electron Lasers
- Spacecraft and Cryogenic Technologies
- Distributed and Parallel Computing Systems
- Particle accelerators and beam dynamics
- Particle Detector Development and Performance
- Particle physics theoretical and experimental studies
- Sensor Technology and Measurement Systems
- Advanced Sensor Technologies Research
- High-Energy Particle Collisions Research
- Fault Detection and Control Systems
- Machine Fault Diagnosis Techniques
- Flow Measurement and Analysis
- Superconductivity in MgB2 and Alloys
- Electrical and Bioimpedance Tomography
- Nuclear reactor physics and engineering
- Scientific Measurement and Uncertainty Evaluation
- Graphite, nuclear technology, radiation studies
- Structural Health Monitoring Techniques
- Heat Transfer and Optimization
- Parallel Computing and Optimization Techniques
- Heat Transfer and Boiling Studies
- Dark Matter and Cosmic Phenomena
- Image Enhancement Techniques
- Radiation Effects in Electronics
European Organization for Nuclear Research
2014-2023
Linde (United States)
2012
Fermi National Accelerator Laboratory
2012
Cryogenic Industries (United States)
2012
Michigan State University
2012
Cryomagnetics (United States)
2012
RIKEN BNL Research Center
2010
Plasma Technology (United States)
2010
Princeton University
2010
Devon History Society
2010
A transducer based on a virtual flow meter is proposed for monitoring helium distribution and consumption in cryogenic systems particle accelerators. The allows technical economical constraints, preventing installation of physical instruments all the needed measurement points, to be overcome. Virtual performance alternative models Samson [ http://www.samson.de (2015)] Sereg-Schlumberger http://www.slb.com/ compared with standard IEC 60534-2-1 [Industrial-process control valves-Part 2-1: Flow...
CERN operates and maintains the world largest cryogenic infrastructure ranging from ageing installations feeding detectors, test facilities general services, to state-of-the-art system serving flagship LHC machine complex. After several years of exploitation a wide range in particular following last two major shutdown maintain consolidate machine, we have analysed reviewed maintenance activities implement an efficient reliable installations. We report results, statistics lessons learned on...
The Large Hadron Collider (LHC) cryogenic system comprises eight independent refrigeration and distribution systems that supply the 3.3 km long accelerator sectors with power as well four for needs of detectors ATLAS CMS. In order to ensure highest possible reliability installations, it is important apply a centred approach maintenance. Even though large scale exists since mid 20th century, very little third party data available today. CERN has started collect its computer aided maintenance...
The ATLAS detector is presently under construction as one of the five LHC experiment set-ups. It relies on a sophisticated magnet system for momentum measurement charged particle tracks. superconducting solenoid at center detector, part nearest to proton-proton collision point. designed 2 Tesla strong axial magnetic field point, while its thin-walled 0.66 radiation lengths avoids degradation energy measurements in outer calorimeters. and calorimeter have been integrated their common...
Appearance in High Dynamic Range (HDR) images is controlled by intraocular glare and simultaneous contrast. This paper describes unique test targets that simulate real images. They change the HDR range 500 times without significantly changing veiling on retina. As well, these have nearly constant Using we measured of appearances possible from with different average luminances. The displayed a maximum luminance 5.4 log unit. Hoverever, results show usable luminances for full (white to black)...
Abstract The CERN cryogenic facilities demand a versatile, distributed, homogeneous and highly reliable control system. For this purpose, conceived developed several frameworks (JCOP, UNICOS, FESA, CMW), based on current industrial technologies COTS equipment, such as PC, PLC SCADA systems complying with the requested constraints. system nowadays uses these allows joint development of supervision layers by defining common structure for specifications code documentation. Another important...
Since 2009, the Large Hadron Collider (LHC) is in operation at CERN. The LHC superconducting magnets distributed over eight sectors of 3.3-km long are cooled 1.9 K pressurized superfluid helium. nominal operating temperature produced by 1.8-K refrigeration units based on centrifugal cold compressors (3 or 4 stages depending to vendor) combined with warm volumetric screw sub-atmospheric suction. After about 5 years continuous operation, we will present results concerning availability for...
Evolutionary approach to centralized multiple-faults diagnostics is extended distributed transducer networks monitoring large experimental systems. Given a set of anomalies detected by the transducers, each instance multiple-fault problem formulated as several parallel communicating sub-tasks running on different and thus solved one-by-one spatially separated processes. A micro-genetic algorithm merges evaluation time efficiency, arising from small-size population parallel-synchronized...
<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> The large ATLAS superconducting magnets system consists of the Barrel, two End-Caps Toroids and Central Solenoid. eight separate coils making Barrel Toroid (BT) have been individually tested with success in a dedicated surface test facility 2004 2005 afterwards assembled underground cavern experiment. In order to fulfill all cryogenic scenarios foreseen for these cold mass 370 tons, helium...
The cryogenic infrastructure at CERN was originated in the 1960s with era of bubble chambers and associated superconducting solenoids. Since then especially construction LHC accelerator its detectors, large complex cryogenics plants have been installed to provide cooling power from 800 W 18 kW different temperatures down 1.9 K, demanding high distributed technical capabilities control systems. size complexity dedicated has required adoption standard framework UNICOS order enhance ease...
The ATLAS detector for the LHC at CERN requires a superconducting solenoid, which provides magnetic field inner detector. central solenoid and its associated proximity cryogenics system has been designed by KEK in collaboration with CERN. Following construction preliminary tests Toshiba Japan equipment shipped to is being prepared integration common cryostat LAr calorimeter, whereafter full on-surface test be completed before final installation 100 m underground cavern. For this purpose...
ATLAS, one of the experiments LHC accelerator under commissioning at CERN, is equipped with a large superconducting magnet Barrel Toroid (BT) that has been tested nominal current (20500 A). The BT composed eight race-track coils (each weights about 45 tons) forming biggest air core toroidal ever built. By means throughput centrifugal pump, forced flow (about 10 liter/second 4.5 K) provides indirect cooling in parallel. paper describes results measurements carried out on complete cryogenic...
Abstract The Large Hadron Collider (LHC) operates using superfluid helium provided by eight large refrigeration units (2.4 kW @ 1.8 K each). These supplied specialized cryogenic industrial suppliers are composed of serial hydrodynamic cold compressors based on an axial-centrifugal impeller coupled with volumetric warm screw compressors. process control systems delivered the have been installed, commissioned and operated reliably for more than 13 years. However, implemented closed...
The potential of cryogenic helium flows for studying high-Reynolds number turbulence in the laboratory has been recognized a long time and implemented several small-scale hydrodynamic experiments. With its large superconducting particle accelerators detector magnets, CERN, European Laboratory Particle Physics, become major world center cryogenics, with refrigerators having capacities up to 18 kW @ 4.5 K. Combining small fraction these resources expertise three laboratories at forefront...
CERN operates and maintains the world largest cryogenic infrastructure ranging from ageing but well maintained installations feeding detectors, test facilities general services, to state-of-the-art system serving flagship LHC machine complex. A study was conducted a methodology proposed outsource industry operation maintenance of whole infrastructure. The coupled non LHC-detectors, services have been fully outsourced for on basis performance obligations. contractor is responsible operational...
Abstract During the second run of Large Hadron Collider (LHC) between 2015 and 2018, significant beam induced heat loads have been observed on screens circuits impacting cryogenic system capacity, mainly due to electron clouds generated by beams. To validate these measurements obtain precise load assessments comparison with preliminary calculations based existing hardware equipment at selected locations, it was decided add new instrumentation around machine. In total, 23 Coriolis flowmeters...
The metrological performance of a virtual flowmeter-based transducer for monitoring helium under cryogenic conditions is assessed. At this aim, an uncertainty model the transducer, mainly based on valve model, exploiting finite-element approach, and flowmeter Sereg-Schlumberger method, are presented. models validated experimentally case study in systems at European Organization Nuclear Research (CERN). impact sources assessed by sensitivity analysis, statistical experiment design analysis...