THE subject of quantum electrodynamics is extremely difficult, even for the case of a single electron. The usual method of solving the corresponding wave equation leads to divergent integrals. To avoid these, Prof. P. A. M. Dirac* uses the method of redundant variables. This does not abolish the difficulty, but presents it in a new form, which may be dealt with in two ways. The first of these needs only comparatively simple mathematics and is directly connected with an elegant general scheme, but unfortunately its wave functions apply only to a hypothetical world and so its physical interpretation is indirect. The second way has the advantage of a direct physical interpretation, but the mathematics is so complicated that it has not yet been solved even for what appears to be the simplest possible case. Both methods seem worth further study, failing the discovery of a third which would combine the advantages of both.

http://ieeexplore.ieee.org/iel5/3/22993/01069961.pdf

Quantum electrodynamics

The Serpent Monte Carlo reactor physics burnup calculation code has been developed at VTT Technical Research Centre of Finland since 2004, and is currently used in over 100 universities and research organizations around the world. This paper presents the brief history of the project, together with the currently available methods and capabilities and plans for future work. Typical user applications are introduced in the form of a summary review on Serpent-related publications over the past few years.

The Serpent Monte Carlo code: Status, development and applications in 2013

Annual Energy Outlook 2008 With Projections to 2030

This is cne of the r-are text books written in the discipline of Nuclear Reactor Analysis, where the author has considered the interests of both scientists and practising engineers, in addition to serving the needs of the academia. The most attractive feature of this book is a balanced treatment of theory and practice of the subject matter. The theoretical foundations of the reactor design methods are explained with simplified definitions and relevant practical illustrations. The author scans through quickly the traditional aspects of the so-called reactor physics and takes the reader through the details of the analytical aspects in a conventional manner. Hcwever, there is a definite departure from the classical method of approach in order to avoid lengthy and repetitive discussions, that are available in many standard text books on reactor physics. The chief departure fran tradition is the priority accorded to the treatment of the energy part of the problems as opposed to the spatial Dart normally devoted to by other authors . A similar unorthodox approach has been applied while dealing with the solution of the various equations by giving priority to computer oriented mrethods as opposed to the classical solutions.

Nuclear reactor analysis

Accident tolerant fuel cladding development: Promise, status, and challenges

Fuel cycle performance of intermediate spectrum reactors with U/Th feed and continuous recycling of U/TRU and Th/U3

A new concept; termed ADAPT; for the rapid and virtually complete burning of plutonium is described. ADAPT employs a high current CW linear accelerator (linac) to generate neutrons in a lead/D2O target. The neutrons are then absorbed in a surrounding subcritical (Keff∼0.95) blanket assembly, that holds small (∼0.5 cm diameter) graphite beads containing the plutonium to be burned. The graphite beads are coated and sealed to contain all fission products, including the noble gases. After destruction of virtually all (≥90%) of the original plutonium loading, the fuel beads are discharged and sent to a geologic repository for ultimate disposal.

/pdf/the-adapt-concept-an-accelerator-driven-system-for-the-rapid-43gfrflz5o.pdf

The ADAPT concept—an accelerator driven system for the rapid and efficient disposal of plutonium

This paper discusses modification of the U.S. Department of Energy's (DOE) Technology Readiness Assessment Guide (DOE G 413.3-4A) for use in the Office of Nuclear Energy's Nuclear Technology Research and Development (NTRD) program. DOE 413.3-4A describes an approach for identifying and managing technology risks in large construction projects to ensure technology development is part of the project baseline and technology maturity is sufficiently advanced before including a technology in the facility design. The process includes the identification of Critical Technology Elements (CTEs), followed by in-depth evaluation of Technology Readiness Levels (TRLs) and development of Technology Maturation Plans (TMPs) for those CTEs. This approach was augmented for the NTRD program to include System Readiness Levels (SRLs) as a complement to TRLs, and developing perspective tracks to better organize the TRL/SRL evaluations that determine the level of knowledge/maturation of the CTEs (e.g. Experiments & Modeling, Safety & Hazards, Manufacturing, etc.). The augmented approach was tested on two areas of research in 2017 (metallic nuclear fuels and fuel dissolution for recycling) and is now being applied to a complete advanced nuclear fuel cycle (from uranium mining to waste disposal).

Technology and System Readiness Assessment for a Nuclear Energy R&D Program

The objective of recent studies as part of a joint NERI project between Brookhaven National Laboratory and Massachusetts Institute of Technology was to develop a seed and blanket unit (SBU) fuel assembly (FA) for thorium utilization in pressured water reactors (PWR). This heterogeneous design utilizes enriched uranium seed and mixed uranium/thorium dioxide blanket fuel pins in physically separable sub-assemblies, and could be used as a one-for-one replacement of more conventional UO2 FA’s in PWRs. The seeds are used for three 18-month cycles in a 3-batch fuel core management strategy, while the blankets are used for six 18-month cycles before being removed for long-term storage; the concepts considered here assume a once-through fuel cycle consistent with current U.S. policy. The SBU should have improved proliferation, radiation safety, and comparable economic characteristics in comparison to existing PWR FA’s. Optimization studies using the BOXER, COBRA-EN, and ORIGEN codes have led to an improved SBU FA design for PWRs that achieves high burnup (80 GWd/t over 3 cycles for SBU) with reduced proliferation and toxicity characteristics, while satisfying thermal-hydraulic safety limits (minimum departure from nucleate boiling ratio greater than 1.3 for 118% over-power). The SBU is an attractive fuel for existing and next-generation PWR.

Michael Todosow

Papers

Fuel cycle performance of intermediate spectrum reactors with U/Th feed and continuous recycling of U/TRU and Th/U3

The ADAPT concept—an accelerator driven system for the rapid and efficient disposal of plutonium

Technology and System Readiness Assessment for a Nuclear Energy R&D Program

Optimization Studies for Seed-and-Blanket Unit (SBU) Fuel Assemblies in PWRs

High power from fixed-field rings in the ads-reactor application