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[en] Activity in the field of nuclear data for the fission power technology applications is reviewed. The present situation is of concern to the French nuclear industry because of the few measurement facilities which are now funded for work in the field and the reductions in the number of scientists expert in measurement and evaluation of nuclear data. It is argued that there are requirements which justify work to improve many items of nuclear data. (authors)
[en] The decommissioning and environmental remediation of civil nuclear facilities represents a considerable challenge for the countries involved in this activity around the world. It includes aspects and problems associated with management, technology, safety and the environment. Over the past few decades, operators worldwide have acquired important experience in the decommissioning and environmental remediation of nuclear sites. A large number of nuclear facilities have ceased operations, and it is envisaged that this number will increase considerably over the coming years. Seventeen power reactors have already been decommissioned, out of more than 150 power reactors shut down or undergoing decommissioning, while more than 180 research reactors have been shut down or are being decommissioned with more than 300 already fully decommissioned. A total of 170 other nuclear cycle facilities have been shut down or are being decommissioned and a further 125 have been completely decommissioned. Spain is one of the countries with experience and activity under way in this field.
[en] In the last 60 years, the scientists spent tens of billion dollars attempting to develop useful thermonuclear energy. But they cannot yet reach a stable thermonuclear reaction. They still are promising publicly, after another 15-20 years, more tens of billions of US dollars to finally design the expensive workable industrial installation. The author offers a new, small, cheap cumulative inertial thermonuclear reactor, which increases the pressure and temperature of its nuclear fuel thousands of times, reaches the required ignition stage and, ultimately, full constant contained thermonuclear reaction. Cumulative reactor contains several innovations to achieve its product. It is safe and ecological. The author is aware that no cumulative pressure research was done anywhere else in the world, especially with additional rocket acceleration. The chief among them is using moving explosives (rocket thrust), which allows to accelerate the special piston to a very high speed (more 30 km/s) which (as it is shown by integral computations) compresses the fuel capsule a million times and heats up million degrees of temperature. The author gives detailed computations of the Lawson criterion. He shows the current conventional inertial laser method gives only 0.28 < 1 of the needed Lawson criterion of thermonuclear reaction (ρR > 1 g/cm2). The offered method gives 585 > 1 of the needed Lawson criterion. The proposed method cannot only achieve but also significantly exceed the Lawson criterion. The experimental reactor is about a thousand times cheaper than a typical laser unit.
[en] Research reactors should incorporate the measurement system for the core power to control and regulate the reactor power. The research reactor modeled in this paper is also equipped with three separate and independent detectors to measure the core power; Neutron Measurement System (NMS), Reactor Gamma Monitoring System (RGMS) and Primary coolant Gamma Monitoring System (PGMS). To calibrate these detectors, the thermal power is used as calibration reference. Therefore, it should be ensured that the thermal power be defined to be fully representative of the core power. The thermal power is calculated based on the thermal balance in the reactor pool where the reactor core and heavy water vessel as the heat source are located. In this paper, the calculation logic for the thermal power is explained in detailed and the precautions for calibration are introduced as well. The equation for the core thermal power has been derived according to measuring parameters such as mass flow rate, and temperatures. In addition, the precautions for calibration such as calibration sequence and pool water effect are clarified as well.
[en] In a research reactor, a CAR(Control Absorber Rod) interface module which receives the control information from the RRS(Reactor Regulating System) control computer and transfer control signal to a step motor in a CAR has been composed of an interface card, an indexer card and a driver card. Due to such separated interface components, the additional interface for each component was inevitable. That is, a CAR interface was more complicated and its corresponding communication ports, drivers and signal cables were unnecessarily required. To simplify this stuff, the interface card and indexer card are integrated to one module and integrated communication network including a step motor driver card can be established through backplane network. The CAR interface module has not been redundant because power operation excluding a CAR by a failure in CAR could be available thanks to remained CARs. But, actually in spite of one CAR failure, operation with remained CARs normally is likely impossible to keep track of rapid dynamics. To solve this problem, the modular redundant structure is introduced herein and this method will let us anticipate the high reliability
[en] The objective of this test program is to obtain the experimental data of pressure drop and subchannel flow distribution for the KMRR (Korea Multipurpose Research Reactor) fuel assembly, and to investigate mechanical integrity of the fuel assembly and flow tube in the test flow condition. The experimental data produced through this study are applicable to the KMRR fuel design and thermal-hydraulic analysis of the reactor. Pressure drop correlations for each types of fuels were developed which can be applicable over Reynolds number of 6x9x102∼8.0x104. Local velocity in the subchannels of the fuel assemblies was measured with laser doppler velocimeter system, and the velocitily distribution was also calculated with a computer program developed through this study. The experimental data are used as input for the core thermal margin analysis and safety analysis in steady/accident conditions of the KMRR. (Author)
[en] The guideline which entered into force on 3 June 1988 governs the qualification and further training requirements to be met by persons who are responsible for ensuring atomic safety and radiation protection during commissioning, operation, maintenance, and decommissioning of research and training reactors as well as subcritical assemblies
[en] This Standard identifies the elements of an emergency plan which describes the approach to coping with emergencies and minimizing the consequences of accidents at research reactor facilities. The emphasis given each of these elements shall be commensurate with the potential risk involved. The emergency plan shall be implemented by emergency procedures
[en] A description and a survey of the main specifications of the Budapest Polytechnical University training reactor are given. The significance is assessed of the reactor for training and scientific purposes and the main tasks are outlined using the reactor in the fields of reactor physics and neutron activation analysis. (B.S.)