A5007190258- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Nuclear Physics and Applications
- Spacecraft and Cryogenic Technologies
- Magnetic confinement fusion research
- Particle Accelerators and Free-Electron Lasers
- Nuclear reactor physics and engineering
- Intermetallics and Advanced Alloy Properties
- High-Temperature Coating Behaviors
- Plasma Diagnostics and Applications
- Corrosion Behavior and Inhibition
- Metallurgical Processes and Thermodynamics
- Molten salt chemistry and electrochemical processes
- Fusion materials and technologies
- Radiation Effects in Electronics
- Thermal and Kinetic Analysis
- Hydrogen embrittlement and corrosion behaviors in metals
- Nuclear Materials and Properties
- Magnesium Oxide Properties and Applications
- High Temperature Alloys and Creep
- Advanced materials and composites
- Nuclear Engineering Thermal-Hydraulics
- Phase Change Materials Research
- Adsorption and Cooling Systems
- Metal Alloys Wear and Properties
Oak Ridge National Laboratory
2014-2024
China Spallation Neutron Source
2024
Thomas Jefferson National Accelerator Facility
2008-2024
Spallation Neutron Source
2024
In order to define the mechanisms that control corrosion of current collector materials in molten carbonate fuel cells, iron with melts at 650°C was investigated. Thermochemical calculations were used identify equilibrium products and establish phase stability diagrams for Fe‐Li‐K‐C‐O system. The a 2.0 mg/cm2 deposit under proceeded according parabolic rate law, where controlled by diffusion cations through inner layers. Pa followed linear rate, controlling step dissolution oxygen from gas...
The equilibrium solubilities of and in were determined at 650°C under controlled oxidizing conditions simulating those molten carbonate fuel cells. Both materials appear to dissolve by a nonredox dissolution process, since the are independent partial pressures over ranges studied. Equilibrium mixture be 78 wppm iron 13.7 weight percent chromium, respectively.
Abstract The Spallation Neutron Source at Oak Ridge National Laboratory operates the Cryogenic Moderator System (CMS) which provides hydrogen cooling 20K to three neutron moderators. Each loop is protected by multiple burst discs and reclosing relief valves. As a result of Proton Power Upgrade project, CMS moderator loops will hold more thus require piping modifications. Operational experience has demonstrated that transient pressure increases in these occasionally rupture discs. causes for...
Abstract Through support of the US Department Energy’s Office Basic Energy Sciences, Oak Ridge National Laboratory has begun applying machine learning methods to improve accelerator and target performance Spallation Neutron Source (SNS). These are being applied control optimization power upgrade SNS Cryogenic Moderator System (CMS). A numerical model CMS been developed study these optimizations system modifications using EcosimPro. This paper compares steady-state transient results with...
Abstract The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) operates the Cryogenic Moderator System (CMS) which provides supercritical hydrogen cooling 20K to three neutron moderators. A helium refrigerator 8 kW of capacity parallel circuits. Several projects have been completed improve operational reliability CMS. status compressor oil removal system, processor, purity monitoring, circulator bearing investigation and procedure improvement will be presented. Future...
The oil injected screw compressors have practically replaced all other types of in modern helium refrigeration systems due to their large displacement capacity, minimal vibration, reliability and capability handling helium's high heat compression.At the present state compressor system designs for systems, typically two-thirds lost input power is compression system. Therefore it important understand isothermal volumetric efficiencies these machines help properly design match process. This...
The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) is preparing for the Proton Power Upgrade (PPU) project to increase output energy of accelerator from 1.0 GeV 1.3 GeV. As part this with combination increasing and beam current, power capability will be doubled 1.4MW 2.8MW. In project, seven new high beta cryomodules housing 28 superconducting niobium cavities added LINAC tunnel. Lessons learned over ten years operation incorporated into cryomodule cavity design....
The Cryogenic Moderator System (CMS) is responsible for maintaining a steady flow of cold neutrons numerous physics experiments at the Spallation Neutron Source (SNS) in Oak Ridge National Laboratory (ORNL). Sudden losses beam power, known as trips, cause major disturbance to CMS due large step changes cooling demands. Ongoing efforts on upgrading neutron power from 1.4 2.0MW are expected generate larger transients that can further strain subsystems if they not properly controlled. To manage...
The Spallation Neutron Source (SNS) is under construction at Oak Ridge National Laboratory. cold section of the Linac consists 81 superconducting radio frequency cavities cooled to 2.1K by a 2400 Watt cryogenic refrigeration system. major system components include warm helium compressors with associated oil removal and gas management, 4.5K box, 7000L liquid dewar, box (consisting 4 stages compressors), gaseous storage, purification impurity monitoring system, nitrogen storage distribution...
The Spallation Neutron Source (SNS) is under construction at Oak Ridge National Laboratory. cold section of the Linac consists 81 superconducting radio frequency cavities cooled to 2.1K by a 2400 watt cryogenic refrigeration system. major system components include warm helium compressors with associated oil removal and gas management, 4.5K box, 7000L liquid dewar, box (consisting 4 stages compressors), gaseous storage, purification impurity monitoring system, nitrogen storage distribution...
The Superconducting Linac at SNS has been operating with beam for almost two years. As the first operational pulsed superconducting linac, many of aspects its performance were unknown and unpredictable. A lot experience gathered during commissioning components, turn on operation increasingly higher power. Some cryomodules have cold well over years extensively tested. consistently conducted 4.4 K 10 15 pulses per second, some tested 30 60 Hz tests performed 2 K. Careful balance between safe...
The Spallation Neutron Source (SNS) superconducting linac (SCL) consists of 11 medium beta (0.61) and 12 high (0.81) RF cryomodules, 32 intersegment quadrupole magnet/diagnostics stations, 9 spool beampipes for future upgrade two differential pumping stations on either end the SCL. cryomodules were designed manufactured by Jefferson Laboratory, magnets beam position monitors furnished Los Alamos National Laboratory. Remaining items Oak Ridge At present SCL is being installed tested. This...
The Spallation Neutron Source (SNS) linear accelerator (LINAC) consists of 81 superconducting radio frequency (SRF) cavities cooled to 2.1 K by a cryogenic refrigeration system. 2-K cold box four stages compressors with liquid nitrogen variable speed motors. Transitioning from 4.5-K operation 2.1-K in the cryomodules involves pumping down approximately 1 bar 0.040 bar. This effort is conducted through use several sequences developed as collaborative between Thomas Jefferson National...
The helium cryogenic system at Spallation Neutron Source (SNS) provides cooling to 81 superconducting radio frequency cavities. During the first ten years of operation, much operational experience and lessons learned have been gained. include integrated issues as well component failures in areas mechanical, electrical controls. Past that corrected current will be detailed this paper. In 2009, a Process Failure Modes Effects Analysis (PFMEA) was completed way identify high risk items...