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Bradley, Eric Craig

Publications and source records attributed to Bradley, Eric Craig.

Complete Non-Radioactive Operability Tests for Cladding Hull Chlorination

Non-radioactive operability tests were made to test the metal chlorination reactor and condenser and their accessories using batch chlorinations of non-radioactive cladding samples and to identify optimum operating practices and components that need further modifications prior to installation of the equipment into the hot cell for tests on actual used nuclear fuel (UNF) cladding. The operability tests included (1) modifications to provide the desired heating and reactor temperature profile; and (2) three batch chlorination tests using, respectively, 100, 250, and 500 g of cladding. During the batch chlorinations, metal corrosion of the equipment was assessed, pressurization of the gas inlet was examined and the best method for maintaining solid salt product transfer through the condenser was determined. Also, additional accessing equipment for collection of residual ash and positioning of the unit within the hot cell were identified, designed, and are being fabricated.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Pre-conceptual design activities for the materials plasma exposure experiment

The development of next step fusion facilities such as DEMO or a Fusion Nuclear Science Facility (FNSF) requires first closing technology gaps in a few critical areas. Understanding the material-plasma interface is necessary to enable the development of divertors for long-pulse plasma facilities. A pre-conceptual design for a proposed steady-state linear plasma device, the Materials Plasma Exposure Experiment (MPEX), is underway. A helicon plasma source along with ion cyclotron and electron Bernstein wave heating systems will produce ITER divertor relevant plasma conditions with steady-state parallel heat fluxes of up to 40 MW/m 2 with ion fluxes up to 10 24 /m 2 s on target. Current plans are for the device to use superconducting magnets to produce 1–2 T fields. As a steady-state device, active cooling will be required for components that interact with the plasma (targets, limiters, etc.), as well as for other plasma facing components (transport regions, vacuum tanks, diagnostic ports). Design concepts for the vacuum system, the cooling system, and the plasma heating systems have been completed. The device will include the capability for handling samples that have been neutron irradiated in order to consider the multivariate effects of neutrons, plasma, and high heat-flux on the microstructure of divertor candidate materials. A vacuum cask, which can be disconnected from the high field environment in order to perform in-vacuo diagnosis of the surface evolution is also planned for the facility.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Zirconium Recycle Test Equipment for Hot Cell Operations

The equipment components and assembly support work were modified for optimized, remote hot cell operations to complete this milestone. The modifications include installation of a charging door, Swagelok connector for the off-gas line between the reactor and condenser, and slide valve installation to permit attachment/replacement of the product salt collector bottle.

42 ENGINEERING↗

Roadside Tracker Portal-less Portal Monitor

This report documents the full development cycle of the Roadside Tracker (RST) Portal-less Portal monitor (Fig. 1) funded by DHS DNDO. The project started with development of a proof-of-feasibility proto-type, proceeded through design and construction of a proof-of-concept (POC) prototype, a test-and-evaluation phase, participation in a Limited Use Exercise that included the Standoff Radiation Detections Systems developed under an Advanced Technology Demonstration and concluded with participation in a Characterization Study conducted by DNDO.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

A CYCLOTRON CONCEPT TO SUPPORT ISOTOPE PRODUCTION FOR SCIENCE AND MEDICAL APPLICATIONS

In August of 2009, the Nuclear Science Advisory Committee (NSAC) recommended a variable-energy, high-current multi-particle accelerator for the production of medical radioisotopes. The Oak Ridge National Laboratory is developing a technical concept for a 70 MeV dual-extraction multi-particle cyclotron that will meet the needs identified in the NSAC report. The cyclotron, which will be located at the Holifield Radioactive Ion Beam Facility (HRIBF), will operate on a 24/7 basis and will provide approximately 6000 hours per year of quality beam time for both the production R&D and production of medical and industrial radioisotopes. The proposed cyclotron will be capable of accelerating dual beams of 30 to 70 MeV H at up to 750 A, and up to 50 A of 15-35 MeV D , 35 MeV H2, and 70 MeV -particles. In dual-extraction H mode, a total of 750 A of 70 MeV protons will be provided simultaneously to both HRIBF and Isotope Production Facility. The isotope facility will consist of two target stations: a 2 water-cooled station and a 4 water-cooled high-energy-beam research station. The multi-particle capability and high beam power will enable research into new regimes of accelerator-produced radioisotopes, such as 225Ac, 211At, 68Ge, and 7B. The capabilities of the accelerator will enable the measurement of excitation functions, thick target yield measurements, research in high-power-target design, and will support fundamental research in nuclear and radiochemistry.

cyclotron↗

AHTR Mechanical, Structural, And Neutronic Preconceptual Design

This report provides an overview of the mechanical, structural, and neutronic aspects of the Advanced High Temperature Reactor (AHTR) design concept. The AHTR is a design concept for a large output Fluoride salt cooled High-temperature Reactor (FHR) that is being developed to enable evaluation of the technology hurdles remaining to be overcome prior to FHRs becoming a commercial reactor class. This report documents the incremental AHTR design maturation performed over the past year and is focused on advancing the design concept to a level of a functional, self-consistent system. The AHTR employs plate type coated particle fuel assemblies with rapid, off-line refueling. Neutronic analysis of the core has confirmed the viability of a 6-month 2-batch cycle with 9 weight-percent enriched uranium fuel. Refueling is intended to be performed automatically under visual guidance using dedicated robotic manipulators. The present design intent is for used fuel to be stored inside of containment for at least 6 months and then transferred to local dry wells for intermediate term, on-site storage. The mechanical and structural concept development effort has included an emphasis on transportation and constructability to minimize construction costs and schedule. The design intent is that all components be factory fabricated into rail transportable modules that are assembled into subsystems at an on-site workshop prior to being lifted into position using a heavy-lift crane in an open-top style construction. While detailed accident identification and response sequence analysis has yet to be performed, the design concept incorporates multiple levels of radioactive material containment including fully passive responses to all identified design basis or non-very-low frequency beyond design basis accidents. Key building design elements include: 1) below grade siting to minimize vulnerability to aircraft impact, 2) multiple natural circulation decay heat rejection chimneys, 3) seismic base isolation, and 4) decay heat powered back-up electricity generation. The report provides a preconceptual design of the manipulators, the fuel transfer system, and the salt transfer loops. The mechanical handling of the fuel and how it is accomplished without instrumentation inside the salt is described within the report. All drives for the manipulators reside outside the reactor top flange. The design has also taken into account the transportability of major components and how they will be assembled on site

Varma, Venugopal Koikal↗

AHTR Refueling Systems and Process Description

The Advanced High-Temperature Reactor (AHTR) is a design concept for a central station-type [1500 MW(e)] Fluoride salt-cooled High-temperature Reactor (FHR) that is currently undergoing development by Oak Ridge National Laboratory for the US. Department of Energy, Office of Nuclear Energy's Advanced Reactor Concepts program. FHRs, by definition, feature low-pressure liquid fluoride salt cooling, coated-particle fuel, a high-temperature power cycle, and fully passive decay heat rejection. The overall goal of the AHTR development program is to demonstrate the technical feasibility of FHRs as low-cost, large-size power producers while maintaining full passive safety. The AHTR is approaching a preconceptual level of maturity. An initial integrated layout of its major systems, structures, and components (SSCs), and an initial, high-level sequence of operations necessary for constructing and operating the plant is nearing completion. An overview of the current status of the AHTR concept has been recently published and a report providing a more detailed overview of the AHTR structures and mechanical systems is currently in preparation. This report documents the refueling components and processes envisioned at this early development phase. The report is limited to the refueling aspects of the AHTR and does not include overall reactor or power plant design information. The report, however, does include a description of the materials envisioned for the various components and the instrumentation necessary to control the refueling process. The report begins with an overview of the refueling strategy. Next a mechanical description of the AHTR fuel assemblies and core is provided. The reactor vessel upper assemblies are then described. Following this the refueling path structures and the refueling mechanisms and components are described. The sequence of operations necessary to fuel and defuel the reactor is then discussed. The report concludes with a discussion of the levels of maturity of the various SSCs to provide guidance for future technology developments. The conceptual design information presented in this report is very preliminary in nature. Significant uncertainty remains about several aspects of the process and even the radiation and mechanical performance of plate-type coated-particle fuel.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗