As part of the reactor dynamics activities of FZK/IRS, the qualification of a detailed 3D CFD model of a reactor pressure vessel is a key step in safety evaluations for improving predictive capabilities and acceptability of commercial CFD tools in reactor physics. The VVER-1000 Coolant Transient Benchmark, initiated by OECD, represents an excellent opportunity for validation. In this work a CFD...

The paper analyses possible types, shapes and locations of defects in a life cycle according to such factors of a urea reactor as material, structure, manufacture approach, work environment, operating medium and failure mode. Then suitable nondestructive testing methods are chosen to test a urea reactor on service on the basis of characteristics of various nondestructive testing methods. And te...

We report on the development of a continuous flow process for the palladium catalysed methoxycarbonylation of aryl, heteroaromatic and vinyl iodides and an aryl bromide using a Teflon AF-2400 based Tube-in-Tube reactor to mediate the selective permeation of carbon monoxide into solution at elevated pressures. The low volume of pressurised gas within the reactor (5.6 mL) offers the potential for...

India has long pursued a fast breeder program, motivated in part by the availability of only poor quality uranium resources within the country. But progress so far has been disappointing, with only one test reactor having been constructed and having a chequered operating history. The larger Prototype Fast Breeder Reactor that is being constructed has a design that compromises safety and will pr...

Significance: Jun 30, 2002 Identified By: NRC Item Type: FIN Finding INADEQUATE DIGITAL FEEDWATER SYSTEM DESIGN AND INADVERTENT GROUNDING OF PLANT EQUIPMENT RESULTS IN REACTOR SCRAM A digital feedwater control system design weakness, in conjunction with the inadvertent grounding of a pressure transmitter during an instrument maintenance surveillance, resulted in a manual reactor scram due to in...

The high temperature gas-cooled reactor (HTGR) is a graphite moderated, helium cooled reactor with ceramiccoated fuel particles (TRISO fuel particles). The HTGR is inherently safe and expected to be applied to various industrial fields such as electric generation, hydrogen production, etc. with high efficiencies. It is also recognized as a representative advanced nuclear system for the future. ...

We propose the use of a proton accelerator to run a slightly subcritical fast breeder and incinerator of minor actinides, and also the use of minor actinides to make a high bumup t%el, which can be burned in a reactor with a non-flattened core with a ratio of height to diameter (H/D= 1). By injecting medium-energy protons into a subcritical assembly, and by supplying external neutrons produced ...

The technique of reaction inhibition is a poorly researched topic. Other methods of runaway reaction control, namely inherent safety, process control, containment, reactor venting, crash cooling and drown-out, are well documented, established techniques that are regularly used for the protection against, or prevention of, runaway chemical reactions. Increasing environmental protection legislati...

Nuclear reactors have, during the first twenty years of their existence, achieved an impressive safety record, possibly exceeding that of any comparable industry. As revealed in apaper byHenriB. Smets of the European Nuclear Energy Agency, there have been recorded during this period of time but six fatalities and less than 30 persons seriously irradiated from reactor accidents. Three of the fat...

This paper considers the maximisation of conversion by manipulating the input flowrate for an exothermic second-order esterification reaction (propionic anhydride + 2-butanol) performed in a semi-batch reactor. Safety considerations impose bounds on the heat release rate in normal operation and on the maximum attainable temperature in the case of cooling failure. The optimal input flowrate is c...