Safety improvement programme of WWER 440/230 units in Jaslovske Bohunice

International Nuclear Information System (INIS)

Tomek, J.

2000-01-01

A brief overview is given of the power sources in Slovakia which include 6 operational reactor units (4 at Jaslovske Bohunice and 2 at Mochovce) and 2 units under construction (at Mochovce). The efforts undertaken in the past 10 years and aimed at upgrading the nuclear safety of the two older (V-230 Soviet type) units at Bohunice are highlighted. The relevant regulatory decisions are dealt with and the measures already carried out are listed. Also characterized are several IAEA international safety assessment missions and safety-aimed meetings which took place in 1998 and 1999 and are of concern to the older Bohunice units. (A.K.)

Bohunice Nuclear Power Plant Safety Upgrading Program

International Nuclear Information System (INIS)

Toth, A.; Fagula, L.

1996-01-01

Bohunice nuclear Power Plant generation represents almost 50% of the Slovak republic electric power production. Due to such high level of commitment to nuclear power in the power generation system, a special attention is given to safe and reliable operation of NPPs. Safety upgrading and operational reliability improvement of Bohunice V-1 NPP was carried out by the Bohunice staff continuously since the plant commissioning. In the 1990 - 1993 period extensive projects were realised. As a result of 'Small Reconstruction of the Bohunice V-1 NPP', the standards of both the nuclear safety and operational reliability have been significantly improved. The implementation of another modifications that will take place gradually during extended refuelling outages and overhauls in the course of 1996 through 1999, is referred to as the Gradual Reconstruction of the Bohunice V-1 Plant. The general goal of the V-1 NPP safety upgrading is the achievement of internationally acceptable level of nuclear safety. Extensive and financially demanding modification process of Bohunice V-2 NPP is likely to be implemented after a completion of the Gradual Reconstruction of the Bohunice V-1 NPP, since the year 1999. With this in mind, a first draft of the strategy of the Bohunice V-2 NPP upgrading program based on Probabilistic Safety assessment consideration was developed. A number of actions with a general effect on Bohunice site safety is evident. All these activities are aimed at reaching the essential objective of Bohunice NPP Management - to ensure a safe, reliable and effective electric energy and heat generation at the Bohunice site. (author)

The results of the surveillance specimen program performed in the RPVs NPP V-2 in Jaslovske Bohunice

Energy Technology Data Exchange (ETDEWEB)

Kupca, L; Beno, P [Vyskumny Ustav Jadrovych Elektrarni, Trnava (Slovakia); Cepeek, S [Atomova Elektraren Bohunice, Jaslovske Bohunice (Slovakia); Tomasich, M [Slovak Nuclear Society, Bratislava (Slovakia)

1994-12-31

After a description of the mechanical and chemical characteristics of the materials (steels, welded joints) used in the pressure vessels of the WWER-440 V-213 type, the present status of the Bohunice NPP Unit 3 and 4 pressure vessel embrittlement assessment programme is presented: neutron flux monitoring and calculations, detector accuracy, irradiation temperature monitoring, reactor core fuel loading calculation, materials, number and types of surveillance specimens, specimen testing. Results are given for 5 years of irradiation: mechanical properties, transition temperatures, lifetime evaluation. 4 refs., 13 figs., 6 tabs.

Nuclear power plant V-1

International Nuclear Information System (INIS)

1999-01-01

In this leaflet the short history of commissioning of Bohunice V-1 NPP is reviewed (beginning of construction 24 April 1972; First controlled reactor power, Reactor Unit 1 (RU1): 27 November 1978, Reactor Unit 2 (RU2): 15 March 1980; Connection to the grid: RU1 17 December 1978, RU2 26 March 1980; Commercial operation: RU1 1 April 1980, RU2 7 January 1981. The scheme of the nuclear reactor WWER 440/V230 is depicted. The major technological equipment (primary circuit, nuclear reactor, steam generators, reactor coolant pumps, primary circuit auxiliary systems, secondary circuit, turbine generators, NPP electrical equipment, and power plant control) are described. Technical data of the Bohunice V-1 NPP are presented

Slovak power stations, Nuclear power plants Jaslovske Bohunice. (Annual report 1997)

International Nuclear Information System (INIS)

1998-01-01

A brief account of activities carried out by the Nuclear power plants Jaslovske Bohunice in 1997 is presented. These activities are reported under the headings: (1) Foreword by the director of Bohunice NPPs; (2) Management of Bohunice NPPs Subsidiary Plant; (3) The most significant events of the year 1997; (4) Electricity and heat production; (5) Safety; (6) Bohunice NPPs operation impact on environment; (7) The V-1 NPP and V-2 NPP upgrading; (8) Maintenance; (9) Capital construction; (10) Economic balance; (11) International co-operation; (12) Human sources; (12) Public relations

Bituminization plant Jaslovske Bohunice

International Nuclear Information System (INIS)

1999-01-01

In this leaflet the principle of the bituminization plant for radioactive concentrate (the intermediate liquid radioactive waste generated during the NPP A1, V-1, V-2 operations) solidification used in the Bohunice Radwaste Treatment Centre (BSC RAO) is presented

ESTE EMO and ESTE EBO - emergency response system for NPP Mochovce and NPP Bohunice V-2

International Nuclear Information System (INIS)

Caeny, P.; Chyly, M.; Suchon, D.; Smejkalova, E.; Fabova, V.; Mancikova, M.; Muller, P.

2009-01-01

Programs ESTE EMO and ESTE EBO are emergency response systems that help the crisis staff of the NPP in assessing the source term (predicted possible release of radionuclides to the atmosphere ), in assessing the urgent protective measures and sectors under threat, in assessing real release (symptoms of release really detected and observed), in calculating radiological impacts of real release, averted or avertable doses, potential doses and doses during transport or evacuation on specified routes. Both systems serve as instruments in case of severe accident (DBA or BDBA) at NPP Mochovce or NPP Bohunice, accidents with threat of release of radioactivity to the atmosphere. Systems are implemented at emergency centre of Mochovce NPP and Bohunice NPP and connected online to the sources of technological and radiological data from the reactor, primary circuit, confinement, secondary circuit, ventilation stack, from the area of NPP (TDS 1) and from the emergency planning zone (TDS 11). Systems are connected online to the sources of meteorological data, too. (authors)

ESTE EMO and ESTE EBO - emergency response system for NPP Mochovce and NPP Bohunice V-2

International Nuclear Information System (INIS)

Caeny, P.; Chyly, M.; Suchon, D.; Smejkalova, E.; Fabova, V.; Mancikova, M.; Muller, P.

2008-01-01

Programs ESTE EMO and ESTE EBO are emergency response systems that help the crisis staff of the NPP in assessing the source term (predicted possible release of radionuclides to the atmosphere ), in assessing the urgent protective measures and sectors under threat, in assessing real release (symptoms of release really detected and observed), in calculating radiological impacts of real release, averted or avertable doses, potential doses and doses during transport or evacuation on specified routes. Both systems serve as instruments in case of severe accident (DBA or BDBA) at NPP Mochovce or NPP Bohunice, accidents with threat of release of radioactivity to the atmosphere. Systems are implemented at emergency centre of Mochovce NPP and Bohunice NPP and connected online to the sources of technological and radiological data from the reactor, primary circuit, confinement, secondary circuit, ventilation stack, from the area of NPP (TDS 1) and from the emergency planning zone (TDS 11). Systems are connected online to the sources of meteorological data, too. (authors)

Lifetime evaluation of Bohunice NPP components

International Nuclear Information System (INIS)

Kupca, L.

2001-01-01

The paper discuss some aspects of the main primary components lifetime evaluation program in Bohunice NPP which is performed by Nuclear Power Plant Research Institute (NPPRI) Trnava in cooperation with Bohunice and other organizations involved. Facts presented here are based on the NPPRI research report which is regularly issued after each reactor fuel campaign under conditions of project resulted from the contract between NPPRI and Bohunice NPP. For the calculations, there has been used some computer codes adapted (or made) by NPPRI and the results are just the conclusive and very brief, presented here in Tables (Figures). (authors)

Reuse of discharged fuel in Bohunice-1,2 units

International Nuclear Information System (INIS)

Chrapciak, V.; Majercik, J.; Kacmar, M.

2003-01-01

During the reconstruction of Bohunice-1,2 units (1997 - 2001), their cycle lengths dropped to very short values. Because of 4-year limit to fuel residence time, refuelling with fresh 2.4 % enriched assemblies seemed to be a solution of the problem. The paper describes the implementation of a final decision to reuse 3.6 % enriched fuel discharged after 3-year irradiation in previous cycles. This decision led to a large-scale moving of discharged assemblies from spent fuel pools back to reactors (Authors)

Optimization of radiation protection at Bohunice NPP

International Nuclear Information System (INIS)

Dobis, L.; Svitek, J.

2003-01-01

Bohunice Nuclear Power Plant is situated in south - western part of Slovakia about 50 km away from Bratislava. There are four PWR reactors 440 MW e each - two units with reactors WWER - 230 (V1 NPP) and two units with WWER - 213 (V2 NPP). requirements for the optimization process are given in the mentioned Code No.12 of Ministry of Health. Code 12 stipulates the technical and organizational requirements for proving the Rational Achievable Level (RAL) of radiation protection. This level can be proved by means of the comparison of the dose distribution to the costs of protection. An example of two figures of dose constraints is: collective dose 20 man mSv for the specific task; individual exposure 1 mSv per day. The values of the financial equivalents of personal exposure - so called the alpha coefficients - are used for the calculation of the benefit of proposed measures. Impact of legislative changes into Bohunice NPP and optimization process are presented. Apparently the new law and the associate code created a base of transparent and understandable policy of radiation protection and optimization in Slovak Republic. The radiation protection legislative was implemented into the praxis and persons became familiar with it. Defining clear and unambiguous terms facilitated the communication between users and the regulatory body - State Health Institute. Optimization was generally accepted by the workers and managers and began to be a part of safety culture of operation at nuclear power plants. (authors)

The primary circuit materials properties results analysis performed on archive material used in NPP V-1 and Kola NPP Units 1 and 2

Energy Technology Data Exchange (ETDEWEB)

Kupca, L.; Beno, P. [Nuclear Power Plants Research Institute Inc., Trnava (Slovakia)

1997-04-01

A very brief summary is provided of a primary circuit piping material properties analysis. The analysis was performed for the Bohunice V-1 reactor and the Kola-1 and -2 reactors. Assessment was performed on Bohunice V-1 archive materials and primary piping material cut from the Kola units after 100,000 hours of operation. Main research program tasks included analysis of mechanical properties, corrosion stability, and microstructural properties. Analysis results are not provided.

Experience in modernization of safety I and C in VVER 440 nuclear power plants Bohunice V1 and Paks

International Nuclear Information System (INIS)

Martin, M.

2000-01-01

For nuclear power plants which have been in operation for more than 15 years, backfitting or even complete replacement of the instrumentation and control (I and C) equipment becomes an increasingly attractive option, motivated not only by the objective to reduce the cost of I and C system maintenance and repair but also to prolong or at least to safeguard the plant life-time: optimized spare-part management through use of standard equipment; reduction of number and variety of different items of equipment by implementing functions stepwise in application software; adding new functionality in the application software which was not possible in the old technology due to lack of space; safeguarding of long-term After-Sales-Service. Some years ago Bohunice V1 NPP, Slovak Republic and Paks NPP, Hungary intended to replace parts of their Safety I and C, mainly the Reactor Trip System, the Reactor Limitation System and the Neutron Flux Excore Instrumentation and Monitoring Systems. After a Basic Engineering Phase in Bohunice V1 and a Feasibility Study in Paks both plants decided to use the Siemens' Digital Safety I and C System TELEPERM XS to modernize their plants. Both Bohunice, Unit 2 and Paks, Unit 1 have been back on line for over six months with the new Digital Safety I and C. At the present time Bohunice, Unit 1 and within the next few months Paks, Unit 2 will be replaced. Trouble-free start-ups and no major problems under operation in the first two plants were based on: thorough understanding of the VVER 440 technology; comprehensive planning together with the plant operators and authorities; the possibility to adapt TELEPERM XS to every plant type; the execution of extensive pre-operational tests. Regarding these modernization measures Siemens, as well as the above Operators, have gained considerable experience in the field of I and C Modernization in VVER 440 NPPs. Important aspects of this experience are: how to transfer the VVER technology to TELEPERM XS; how to

Safety enhancement in NPP Bohunice

International Nuclear Information System (INIS)

Lipar, M.; Mihalik, M.

1997-01-01

The upgrading and safety enhancement of both the Bohunice V-1 and V-2 reactors is described in detail. The total estimated cost of the gradual reconstruction of these two units during 1996 to 1999 is 180 mil. US dollars. For the 1995 to 1997 period, the actions common for both units include a quality assurance programme, a personnel training programme, installation of a multifunction simulator, implementation of symptom-oriented operation procedures, installation of diagnostic systems, of a site security system, and of a teledosimetric system. At present, the main maintenance tasks are: to carry out major repair of units, to remedy service interruptions, to enhance equipment service availability, to enhance the technical level of corrective actions at equipment. Investment into maintenance level upgrade has grown from 7.5 mil. Slovak crowns in 1994 to estimated 32 mil. in 2000. The partners of international cooperation are mentioned. (M.D.)

Radiation protection in Bohunice NPP. Description of present status

International Nuclear Information System (INIS)

Dobis, L.

2001-01-01

Radiation protection (RP) at Bohunice NPP has reached the high international standard. The fact was approved by several independent international missions (OSART , WANO, WENRA, ...). A lot of modifications have been done in order to improve the standard of radiation protection. All the BSS requirements have been implemented into the plant regulations before the State Law No 290/1996 and 470/2000 came into the force. Internal audits are regularly performed at NPP in order to reveal potential deficiencies. In 2001 there were 4 such audits focused on quality assurance, software operation, LBB concept and limits and condition of safe operation. State Health Institute, the regulatory body in the radiation protection, performs the inspection at least ones a month. Good relationship with the inspectors of State Health Institute also contributes to the safe operation of the NPP. There were not any radiation accident. All anomalies or radiation events are investigated at a plant level. The results of root cause analysis and proposal of corrective actions are provided to IAEA and WANO databases for the distribution. The Radiation protection department of Bohunice NPP cooperates with the other Czech and Slovak NPPs. Regular meetings on radiation protection and lately also on emergency preparedness are organized. The cooperation is excellent. Occupational exposure is reviewed also with respect of ISOE data. Bohunice NPP (even with high dose burden caused by reconstruction of V1 NPP) can be found in the first half of world PWR speaking about the collective exposure per reactor. V2 NPP itself reaches the lowest collective exposure in the world. All doses are below the limits and kept ALARA. ALARA system has been established already in 1997 at Bohunice NPP and its results are obvious for example looking at dose results during the reconstruction works at V1 NPP. The operation of Bohunice NPP has negligible influence to its surroundings. The values of gas and liquid effluents move

Risk-informed decision making during Bohunice NPP safety upgrading

International Nuclear Information System (INIS)

Lipar, M.; Muzikova, E.; Kubanyi, J.

2001-01-01

The paper summarizes some facts of risk-informed regulation developments within UJD regulatory environment. Based on national as well as international operating experience and indications resulted from PSA, Nuclear Regulatory Authority of the Slovak Republic (UJD) since its constituting in 1993 has devoted an effort to use PSA technology to support the regulatory policy in Slovakia. The PSA is considered a complement, not a substitute, to the deterministic approach. Suchlike integrated approach is used in decision making processes and the final decision on scope and priorities is based on it. The paper outlines risk insights used in the decision making process concerning Bohunice NPP safety upgrading and focuses on the role of PSA results in Gradual Reconstruction of Bohunice VI NPP. Besides, two other examples of the PSA results application to the decision making process are provided: the assessment of proposal of modifications to the main power supply diagram (incorporation of generator switches) and the assessment of licensee request for motor generator AOT (Allowable Outage Time) extension. As an example of improving support of Bohunice V-2 risk-informed operations, concept of AOT calculations and Bohunice V-2 Risk Monitor Project are briefly described. (author)

Post-reconstruction full power and shut down level 2 PSA study for Unit 1 of Bohunice V1 NPP

International Nuclear Information System (INIS)

Kovacs, Z.

2003-01-01

The level 2 PSA model of the J. Bohunice V1 NPP was developed in the RISK SPECTRUM Professional code with the following objectives: to identify the ways in which radioactive releases from the plant can occur following the core damage; to calculate the magnitudes and frequency of the release; to provide insights into the plant behaviour during a severe accident; to provide a framework for understanding containment failure modes; the impact of the phenomena that could occur during and following core damage and have the potential to challenge the integrity of the confinement; to support the severe accident management and development of SAMGs. The magnitudes of release categories are calculated using: the MAAP4/VVER for reactor operation and shutdown mode with closed reactor vessel and the MELCOR code for shutdown mode with open reactor vessel. In this paper an overview of the Level 2 PSA methodology; description of the confinement; the interface between the level 1 and 2 PSA and accident progression analyses are presented. An evaluation of the confinement failure modes and construction of the confinement event trees as well as definition of release categories, source term analysis and sensitivity analyses are also discussed. The presented results indicate that: 1)for the full power operation - there is an 25% probability that the confinement will successfully maintain its integrity and prevent an uncontrolled fission product release; the most likely mode of release from the confinement is a confinement bypass after SGTM with conditional probability of 30%; the conditional probability for the confinement isolation failure probability without spray is 5%, for early confinement failure at the vessel failure is 4%, for other categories 1% or less; 2) for the shutdown operating modes - the shutdown risk is high for the open reactor vessel and open confinement; important severe accident sequences exists for release categories: RC5.1, RC5.2 and RC6.2

Chemical composition determination of Bohunice 1 and 2 RPVs and hardness measurements of RPVs material

International Nuclear Information System (INIS)

Kupca, L.; Brezina, M.; Beno, P.; Kniz, I.

1994-01-01

The base informations of all activities concerning the material properties recovery performed before and after annealing procedure on the first two units V-230 type in NPP V-1, are the topic of this paper. The samples of weld and base metal from both RPVs NPP V-1 were prepared by special apparatus in the very narrow gap between the outside surface of the RPV and the reactor thermal shielding in the reactor cavity, from the critical circumferential weld joint no.4. The chemical composition of the samples was analyzed in Nuclear Power Plants Research Institute (VUJE) laboratories. Except these results achieved from the analysis of the irradiated samples are presented the evaluation results of the chemical composition influence on the RPVs materials brittle fracture temperatures. All these results which served as input data for the irradiation embrittlement recovery evaluation of the both RPV NPP V-1 in Jaslovske Bohunice, are presented in the form of the trend curves for both RPVs. (author). 10 refs, 7 figs, 1 tab

The most extensive reconstruction of nuclear power plant with VVER 440/V230 reactor

International Nuclear Information System (INIS)

Ferenc, M.

2000-01-01

The nuclear power plant V-1 Bohunice consists of two VVER-440 units with V-230 reactors. Unit 1 was commissioned in 1978 and Unit 2 in 1980. Large experience and knowledge from the operation of previous units with V-230 reactors were incorporated into the V-1 design, which resulted in a higher level of safety and operational reliability of these units. The Siemens company which won an international bidding process developed these basic goals for the Gradual Upgrading into the so called Basic Engineering (BE). For the implementation of the Gradual Upgrading in line with the BE, Rekon consortium was established consisting of Siemens and VUJE. The implementation of the Gradual Upgrading is scheduled for the time period of 1996 - 2000. Siemens was responsible for the upgrading strategy - based on the approved results of the basic engineering phase and the PSAR, the engineering and realization of all I and C improvements, and also for the seismic upgrade. VUJE's responsibility covered the detailed engineering and implementation of mechanical, electrical and civil part of upgrading measures as well as overall organisation and evaluation of verification tests. The consortium awarded contracts for final planning and design, installation services and commissioning to other Slovakian subcontractors in order to ensure the largest possible local content. The gradual reconstruction of the V-1 Bohunice with V230 reactors represents a comprehensive reconstruction of safety-related systems and equipment. Following its completion, the units will be operated with a safety level accepted internationally. (author)

Thirtieth anniversary of reactor accident in A-1 Nuclear Power Plant Jaslovske Bohunice

International Nuclear Information System (INIS)

Kuruc, J.; Matel, L.

2007-01-01

The facts about reactor accidents in A-1 Nuclear Power Plant Jaslovske Bohunice, Slovakia are presented. There was the reactor KS150 (HWGCR) cooled with carbon dioxide and moderated with heavy water. A-1 NPP was commissioned on December 25, 1972. The first reactor accident happened on January 5, 1976 during fuel loading. This accident has not been evaluated according to the INES scale up to the present time. The second serious accident in A-1 NPP occurred on February 22, 1977 also during fuel loading. This INES level 4 of reactor accident resulted in damaged fuel integrity with extensive corrosion damage of fuel cladding and release of radioactivity into the plant area. The A-1 NPP was consecutively shut down and is being decommissioned in the present time. Both reactor accidents are described briefly. Some radioecological and radiobiological consequences of accidents and contamination of area of A-1 NPP as well as of Manivier Canal and Dudvah River as result of flooding during the decommissioning are presented (authors)

Radwaste Treatment Centre Jaslovske Bohunice

International Nuclear Information System (INIS)

2000-01-01

In this leaflet the Bohunice Radwaste Treatment Centre (BSC RAO) is presented. BSC RAO is designed to process and treat liquid and solid radwaste, arising from the NPP A-1 decommissioning, from NPPs V-1, V-2, and Mochovce operations, as well as institutional radwaste of diverse institutional (hospitals, research institutes) in the Slovak Republic. Transport, sorting, incineration, compacting, concentration and cementation of radwaste as well as monitoring of emission are described

Information letter 2. Information about operation of plants SE-NPP Bohunice and SE-VYZ during February 2005

International Nuclear Information System (INIS)

2005-03-01

In this leaflet results of exploitation of four units of the Bohunice V-1 and V-2 NPPs are presented. The electricity and heat production in February 2005 are reviewed. Within a February 2005 the electricity was produced: 217 GWh (block 1), 281 GWh (block 2), 277 GWh (block 3), 282 GWh (block 4), totally 1057 GWh, and 2271 GWh within a January - February 2005. The heat production in February 2005 was 266 506 GJ, and within a January - February 2005 it was produced 531 849 GJ of heat. On February 17 Slovak minister of economy Pavol Rusko and general director of ENEL Paolo Scaroni signed the agreement on acquisition of 66 per cent of Slovenske elektrarne (SE) by Italian ENEL for 840 million Eur. SE has capacity of around 7 GW (83 per cent of total Slovakian capacity). In 2004 SE generated 26 TWh of electricity. Processing and storage of radioactive wastes in Decommissioning of Nuclear Installations and Spent Fuel and Rad-waste Management (SE-VYZ) is presented. Since beginning of this year 58 fibre-concrete containers have been filled up in Bohunice processing centre of radioactive wastes. Twenty-three pieces of fibre-concrete containers were processed into fibre-concrete containers in Bohunice processing centre of radioactive wastes (BSC RAO) in February 2005. Twenty fibre-concrete containers were stored into Republic storage of radioactive wastes (RU RAO). Total number in RU RAO reached 830 pieces of fibre-concrete containers, which represent 11.53 per cent of storage capacity (7200 containers). Bohunice processing centre of radioactive wastes was put into active operation just before five years

Twenty years of operation of WWER 440/230 units in Jaslovske Bohunice

International Nuclear Information System (INIS)

Tomek, J.

1998-01-01

It is twenty years this year since the first unit WWER 440 of Slovak Nuclear Power Plant Jaslovske Bohunice was commissioned. There are four units WWER 440 in operation Jaslovske Bohunice site. First two units of older soviet PWR design V-230 (also known as V-1) and other two units of newer V-213 type (also known as V-2). The goal of this presentation is to summarize and evaluate the operation of Unit 1 and 2 for this period of time and mainly to describe what has been done and what is planned to be done to increase the nuclear safety and operational reliability of both units. The operating organization and regulatory authority assume that an internationally acceptable level of safety will be reached by accomplishing of the upgrading program.(author)

Nuclear power plant V-1

International Nuclear Information System (INIS)

1998-01-01

The nuclear power plant Bohunice V -1 is briefly described. This NPP consists from two reactor units. Their main time characteristics are (Reactor Unit 1, Reactor Unit 2): beginning of construction - 24 April 1972; first controlled reactor power - 27 November 1978, 15 March 1980; connection to the grid - 17 December 1978, 26 March 1980; commercial operation - 1 April 1980, 7 January 1981. This leaflet contains: NPP V-1 construction; Major technological equipment (Primary circuit: Nuclear reactor [WWER 440 V230 type reactor];Steam generator; Reactor Coolant Pumps; Primary Circuit Auxiliary Systems. Secondary circuit: Turbine generators, Nuclear power plant electrical equipment; power plant control) and technical data

Fuel leak testing performance at NPP Jaslovske Bohunice

International Nuclear Information System (INIS)

Slugen, V.; Krnac, S.; Smiesko, I.

1995-01-01

The NPP Bohunice VVER-440 fuel leak testing experience are relatively extensive in comparison with other VVER-440 users. As the first Europe NPP was adapted Siemens (KWU) in core-sipping equipment to VVER-440 units and since this time were have done these tests also for NPP Paks (Hungary) and NPP Dukovany (Czech Republic). The occurrence of leaking fuel assemblies in NPP is in the last 5 years relatively stabilised and low. A significant difference can be observed between type V-230 (31 leaks) and type V-213 (1 leak). None of of the indicated leaking fuel assemblies has been investigated in the hot cell. Therefore cannot be confirm the effective causes of leak occurrence. Nevertheless, the fuel failure rate and the performance of leak testing in NPP Bohunice are comparable to the world standard at PWR's. 1 tab., 2 figs., 3 refs

Fuel leak testing performance at NPP Jaslovske Bohunice

Energy Technology Data Exchange (ETDEWEB)

Slugen, V; Krnac, S [Slovak Technical Univ., Bratislava (Slovakia); Smiesko, I [Nuclear Powr Plant EBO, Jaslovske Bohuce (Slovakia)

1996-12-31

The NPP Bohunice VVER-440 fuel leak testing experience are relatively extensive in comparison with other VVER-440 users. As the first Europe NPP was adapted Siemens (KWU) in core-sipping equipment to VVER-440 units and since this time were have done these tests also for NPP Paks (Hungary) and NPP Dukovany (Czech Republic). The occurrence of leaking fuel assemblies in NPP is in the last 5 years relatively stabilised and low. A significant difference can be observed between type V-230 (31 leaks) and type V-213 (1 leak). None of of the indicated leaking fuel assemblies has been investigated in the hot cell. Therefore cannot be confirm the effective causes of leak occurrence. Nevertheless, the fuel failure rate and the performance of leak testing in NPP Bohunice are comparable to the world standard at PWR`s. 1 tab., 2 figs., 3 refs.

Bohunice Simulator Data Collection Project

International Nuclear Information System (INIS)

Cillik, Ivan; Prochaska, Jan

2002-01-01

The paper describes the way and results of human reliability data analysis collected as a part of the Bohunice Simulator Data Collection Project (BSDCP), which was performed by VUJE Trnava, Inc. with funding support from the U.S. DOE, National Nuclear Security Administration. The goal of the project was to create a methodology for simulator data collection and analysis to support activities in probabilistic safety assessment (PSA) and human reliability assessment for Jaslovske Bohunice nuclear power plant consisting of two sets of twin units: two VVER 440/V-230 (V1) and two VVER 440/V-213 (V2) reactors. During the project training of V-2 control room crews was performed at VUJE-Trnava simulator. The simulator training and the data collection were done in parallel. The main goal of BSDCP was to collect suitable data of human errors under simulated conditions requiring the use of symptom-based emergency operating procedures (SBEOPs). The subjects of the data collection were scenario progress time data, operator errors, and real-time technological parameters. The paper contains three main parts. The first part presents preparatory work and semi-automatic computer-based methods used to collect data and to check technological parameters in order to find hidden errors of operators, to be able to retrace the course of each scenario for purposes of further analysis, and to document the whole training process. The first part gives also an overview of collected data scope, human error taxonomy, and state classifications for SBEOP instructions coding. The second part describes analytical work undertaken to describe time distribution necessary for execution of various kinds of instructions performed by operators according to the classification for coding of SBEOP instructions. It also presents the methods used for determination of probability distribution for different operator errors. Results from the data evaluation are presented in the last part of the paper. An overview of

Bohunice Simulator Data Collection Project

International Nuclear Information System (INIS)

Cillik, I.; Prochaska, J.

2002-01-01

The paper describes the way and results of human reliability data analysis collected as a part of the Bohunice Simulator Data Collection Project (BSDCP), which was performed by VUJE Trnava, Inc. with funding support from the U.S. DOE, National Nuclear Security Administration. The goal of the project was to create a methodology for simulator data collection and analysis to support activities in probabilistic safety assessment (PSA) and human reliability assessment for Jaslovske Bohunice nuclear power plant consisting of two sets of twin units: two VVER 440/V-230 (V1) and two VVER 440/V-213 (V2) reactors. During the project, training of V-2 control room crews was performed at VUJE Trnava simulator. The simulator training and the data collection were done in parallel. The main goal of BSDCP was to collect suitable data of human errors under simulated conditions requiring the use of symptom-based emergency operating procedures (SBEOPs). The subjects of the data collection were scenario progress time data, operator errors, and real-time technological parameters. The paper contains three main parts. The first part presents preparatory work and semi-automatic computer-based methods used to collect data and to check technological parameters in order to find hidden errors of operators, to be able to retrace the course of each scenario for purposes of further analysis, and to document the whole training process. The first part gives also an overview of collected data scope, human error taxonomy, and state classifications for SBEOP instructions coding. The second part describes analytical work undertaken to describe time distribution necessary for execution of various kinds of instructions performed by operators according to the classification for coding of SBEOP instructions. It also presents the methods used for determination of probability distribution for various operator errors. Results from the data evaluation are presented in the last part of the paper. An overview of

Irradiation temperature measurement of the reactor pressure vessel surveillance specimen in the programmes of radiation degradation monitoring

International Nuclear Information System (INIS)

Kupca, L.; Stanc, S.; Simor, S.

2001-01-01

The information's about the special system of irradiation temperature measurement, used for reactor pressure vessel surveillance specimen, which are placed in reactor thermal shielding canals are presented in the paper. The system was designed and realized in the frame of Extended Surveillance Specimen Programme for NPP V-2 Jaslovske Bohunice and Modern Surveillance Specimen Programme for NPP Mochovce. Base design aspects, technical parameters of realization and results of measurement on the two units in Bohunice and Mochovce NPPs are presented too. (Authors)

Project Management Unit for decommissioning of NPP Bohunice VI (2003-2014)

International Nuclear Information System (INIS)

Gonzalez Fernandez-conde, A.; Brochet, I.; Ferreira, A.

2015-01-01

From October 2003 until december 2014 the Consortium consisting of Iberdrola Engineering and Construction (leader). Empresarios Agrupados Internacional, and Indra Sistemas has carried out the project Project Management Unit ((PMU) for the decommissioning of Bohunice V1 NPP (units 1 and 2), type VVER-440/V-230 in Slovakia. during the first phase (2003-2007) EdF was also part of the Consortium. The project is funded by the Bohunice International Decommissioning Support Fund (BIDSF) administered by the RBRD. The main objective of the project is to provide the necessary engineering and resources of project management for planning, execution, management, coordination and monitoring of all tasks in support of the decommissioning. (Author)

Metamorphosis of NPP A1, V1, V2

International Nuclear Information System (INIS)

Dobak, D.; Moncekova, M.

2005-01-01

In this book the history of construction, commissioning and exploitation of NPP A1, NPP V1 and NPP V2 in Jaslovske Bohunice is presented on documentary photos. Vicinity around of these NPPs is presented, too

Seismic strengthening of nuclear power plants V1-V2 structures in Slovak Republic

International Nuclear Information System (INIS)

David, M.

1993-01-01

The structural upgrading of main buildings of Bohunice NPP units V1 and V2 is described in this presentation. Design criteria for structural upgrading are included. Since the seismic upgrading of the existing NPP is usually very complicated and expensive task, designer is obliged to find the optimal solution between the economics and reliability of the upgrading. The assistance of IAEA missions during the process of Bohunice seismic upgrading is considered very fruitful

The preliminary results of the thermal annealing processes performed on the RPVs NPP V-1 in Jaslovske Bohunice

Energy Technology Data Exchange (ETDEWEB)

Kupca, L; Brezina, M; Beno, P [Vyskumny Ustav Jadrovych Elektrarni, Trnava (Slovakia)

1994-12-31

Samples of weld and base metal above and below the weld were taken from RPV material in the V-230 type NPP V-1 in Bohunice; hardness measurements were carried out across the weld on the external surface of the RPV under the thermal shielding, before and after annealing. Results are presented and the annealing procedure efficiency is discussed. (authors). 13 refs., 5 figs.

Seismic evaluation and strengthening of Bohunice nuclear power plant structures

International Nuclear Information System (INIS)

Shipp, J.G.; Short, S.A.; Grief, T.; Borov, V.; Kuzma, J.

2001-01-01

A seismic assessment and strengthening investigation is being performed for selected structures at the Bohunice V1 Nuclear Power Plant in Slovakia. Structures covered in this paper include the reactor building complex and the emergency generator station. The emergency generator station is emphasized in the paper as work is nearly complete while work on the reactor building complex is ongoing at this time. Seismic evaluation and strengthening work is being performed by a cooperative effort of Siemens and EQE along with local contractors. Seismic input is the interim Review Level Earthquake (horizontal peak ground acceleration of 0.3 g). The Bohunice V1 reactor building complex is a WWER 4401230 nuclear power plant that was originally built in the mid-1970s but had extensive seismic upgrades in 1991. Siemens has performed three dimensional dynamic analyses of the reactor building complex to develop seismic demand in structural elements. EQE is assessing seismic capacities of structural elements and developing strengthening schemes, where needed. Based on recent seismic response analyses for the interim Review Level Earthquake which account for soil-structure interaction in a rigorous manner, the 1991 seismic upgrade has been found to be inadequate in both member/connection strength and in providing complete load paths to the foundation. Additional strengthening is being developed. The emergency generator station was built in the 1970s and is a two-story unreinforced brick masonry (URM) shear wall building above grade with a one story reinforced concrete shear wall basement below grade. Seismic analyses and testing of the URM walls has been performed to assess the need for building strengthening. Required structural strengthening for in-plane forces consists of revised and additional vertical steel framing and connections, stiffening of horizontal roof bracing, and steel connections between the roof and supporting walls and pointing of two interior transverse URM

New Emergency control center of Slovenske Elektrarne Bohunice NPP

International Nuclear Information System (INIS)

Pecko, E.

2012-01-01

Emergency preparedness of nuclear power plant and operation assurance in case of a possible emergency calls to have devices for emergency response with equipment for rapid detection and continuous evaluation of anticipated events. Chief executive body designated to manage a nuclear power plant during major events is the emergency committee (EC). Emergency Committee is a part of the Emergency Response Organization (ERO). The following centers are on alert to ensure the activities of the ERO - Emergency Response office: - control room (CR) and emergency control room (ECR); - emergency management center (EMC); - Monitoring Centre (MC); - emergency backup control center (EBCC); - congregations of civil protection (CP) and CP shelters; - communications with warning and notification system (VARVYR). From a historical and practical point of view in the vicinity of Jaslovske Bohunice has been set up a joint emergency control center. The center was located on the territory of the former already inoperative V1 NPP. V1 NPP is currently integrated into the organizational structure of JAVYS. Operating Bohunice V2 NPP plant is a designated part of the Slovenske Elektrarne, a. s., whose majority owner is an Italian operator ENEL. In terms of various relevant factors, it was decided to build a new emergency management center on the territory of operating V2 NPP, meet the current standards.

Foreword by the director of Bohunice NPPs

International Nuclear Information System (INIS)

1998-01-01

In this foreword the director briefly describes activities of the NPP Bohunice in 1997. Main activities were: electric and heat production , the V-1 NPP Gradual Reconstruction Programme, nuclear safety programmes, environment protection, international co-operation as well as national and international public information

Forty years of atmospheric radiocarbon monitoring around Bohunice nuclear power plant, Slovakia

International Nuclear Information System (INIS)

Povinec, P.P.; Chudy, M.; Sivo, A.; Simon, J.; Holy, K.; Richtarikova, M.

2009-01-01

Radiocarbon variations in the atmospheric CO 2 with attenuating amplitudes and decreasing mean values with typical maxima in summer and minima in winter have been observed since 1967 in two localities of Slovakia, in Bratislava and Zlkovce, situated about 60 km NE from Bratislava, only 5 km from the Bohunice Nuclear Power Plant (NPP). The 14 C record in Bratislava has been influenced mainly by fossil CO 2 emissions, in contrast to the Zlkovce record which has been more variable, as it has clearly been affected by operation of the Bohunice NPP. However, during specific meteorological conditions with NE transport of air masses to Bratislava, the effect of the Bohunice NPP has been visible in Bratislava as well. Maximum 14 C concentrations (up to 120% above a natural background) were observed around A1 NPP which used CO 2 with admixture of air as a cooling agent. The 14 C concentrations around four pressurized light water reactors were up to 30% above the background. The Δ 14 C values in the heavily polluted atmosphere of Bratislava were up to 10% and at Zlkovce up to 5% lower than the European clean air represented by the Jungfraujoch Δ 14 C data. Later the Δ 14 C values were similar at both sites, and from 2003 they were close to the European clean air levels. The observed Δ 14 C behaviour in the atmosphere provides a unique evidence of decreased fossil fuel CO 2 emissions in the region, as well as the long-term effect of the Bohunice NPP on the Bratislava and Zlkovce stations. The estimated annual radiation doses to the local public due to digestion of radiocarbon contaminated food have been estimated to be around 3 μSv

Fire fighting precautions at Bohunice Atomic Power Plants

International Nuclear Information System (INIS)

Anon.

1984-01-01

Some shortcomings are discussed of the project design of fire protection at the V-1 and V-2 nuclear power plants. The basic shortcoming of the system is insufficient division of the units for fire protection. Fire fighting measures are described for cable areas, switch houses and outside transformers, primary and secondary circuits and auxiliary units. Measures are presented for increasing fire safety in Jaslovske Bohunice proceedi.ng from experience gained with a fire which had occurred at a nuclear power plant in Armenia. (E.S.)

District heating by the Bohunice nuclear power plant

International Nuclear Information System (INIS)

Metke, E.; Skvarka, P.

1984-01-01

Technical and economical aspects of district heating by the electricity generating nuclear plants in Czechoslovakia are discussed. As a first stage of the project, 240 MW thermal power will be supplied using bleeding lines steam from the B-2 nuclear power plant at Jaslovske Bohunice to heat up water at a central station to 130 grad C. The maximal thermal power that can be produced for district heating by WWER type reactors with regular condensation turbines is estimated to be: 465 MW for a WWER-440 reactor with two 220 MWe turbines and 950 MW for a WWER-1000 reactor with a Skoda made 1000 MWe turbine using a three-stage scheme to heat up water from 60 grad C to 150 grad C. The use of satelite heating turbines connected to the steam collector is expected to improve the efficiency. District heating needs will de taken into account for siting of the new power plants

Resin intrusion into the primary circuit of NPP Jaslovske Bohunice V-1

International Nuclear Information System (INIS)

Grezdo, O.; Mraz, V.

2005-01-01

During the refueling at the first unit of Bohunice NPP in 2005 a lot of sediment was found on the upper storage rack. This sediment was identification as a filter resin. Resin was found in most of the fuel assemblies, pipes and tanks of the primary circuit and his auxiliary systems. Resin producer and WANO network was contacted in order to get information about similar events. Management of Bohunice NPP made a decision that primary circuit, fuel assemblies and auxiliary systems have to be cleaned. Subsequent cleaning extended outage by 31 days. This paper summarizes causes, existing consequences and corrective actions. Accent was put on the hydraulic characteristics of the primary circuit measurement, power distribution core monitoring and the primary circuit water quality verification (Authors)

National Report

International Nuclear Information System (INIS)

Lipar, M.

2001-01-01

Power production in Slovak Republic is presented. The safety at the NPPs Bohunice V-1, V-2 and Mochovce is discussed. The events - Automatic Reactor Scram at Bohunice 1 and Power Reduction - Home Load at Bohunice 2 due to short circuit in the external grid on 22 May 2001 and Manual Reactor Scram at Mochovce 2 NPP due to Loss of Offsite Power on 30 May 2001 are described

Results of physics start-up tests of Mochovce and Bohunice units with 2-nd generation Gd fuel (average enrichment 4.87 %)

International Nuclear Information System (INIS)

Polakovic, F.

2015-01-01

There are presented main features of the fuel and the list of experimental neutron-physical characteristics measured during physics start-up tests.All together there were carried out 14 physics start-ups at Bohunice and Mochovce Units with the new type of fuel. Differences between theoretical and experimental neutron-physical characteristics were statistically processed and compared with the tests acceptance criteria. There are summarized results of reactor physics start-ups with 2-nd generation Gd fuel usage [ru

Primary system hydraulic characteristics after modification of reactor coolant pumps' impeller wheels at Bohunice NPP executed in 2012 and 2013

International Nuclear Information System (INIS)

Hermansky, Jozef; Zavodsky, Martin

2014-01-01

A coolant flow through the reactor is usually determined after annual outages at Slovak NPP (VVER 440) in two distinct ways. First method is determination on the basis of the secondary system parameters - measurement of thermal balances. The value achieved by this method is used as the input parameter in the Table of allowed reactor operation modes. The second method draws from the primary system parameters - measurement of primary system hydraulic characteristics. Flow nozzles used for the measurement of feed water flow behind high pressure heaters were replaced at both Bohunice Units during outages in 2008. The feed water flow behind high pressure heaters is one of the main parameters used for the determination of coolant flow through the reactor by the first method. Compared to the measurement executed during previous fuel cycles, the calculated coolant flow through the reactor decreased considerably after the change of flow nozzles. The imaginary change of coolant flow through the reactor at Unit 3 was -1,6 %; and at Unit 4 -2,6 %. This change was not proved by the parallel measurement of primary system hydraulic characteristics. Later it was found out that the original flow nozzles used for 25 years were substantially deposited (original inner diameter of the nozzles was reduced by about 0,6-0,9 mm). Therefore feed water flow measurement was untrustworthy within the recent years. On the findings stated above, Bohunice NPP has decided to increase coolant flow through the reactor by changing the reactor coolant pumps impeller wheels. The modification of impellers wheels is planned within years 2012 to 2014. During the outages in 2013 two impeller wheels were replaced at both units. Nowadays Unit 4 is operated with all 6 new impeller wheels and Unit 3 with four new impeller wheels. Modification of last two impeller wheels at Unit 3 will be performed during the outage in 2014. On account of impeller wheels modification, non-standard measurement of PS hydraulic

Final results of the gradual reconstruction of Bohunice VI in Slovakia and evaluation of the reconstruction by international missions

International Nuclear Information System (INIS)

Ferenc, M.

2001-01-01

The gradual reconstruction of the Bohunice V1 nuclear power plant (Slovakia) represents the most extensive reconstruction of a nuclear power plant in operation as implemented worldwide up to now. Extensive reconstruction works in both civil construction and process parts, in instrumentation and control part, and in electric part enhanced both nuclear safety and operational reliability of Bohunice V1 in a significant way.(author)

Increasing of leak-tightness of hermetic zone and other important components in NPPs

International Nuclear Information System (INIS)

Murani, J.

2001-01-01

The performed by VUEZ resealing works in the hermetic compartments/containment of WWER 440 and WWER 1000 NPPs in Slovakia (Jaslovske Bohunice V-1 NPP, Jaslovske Bohunice V-2 NPP, Mochovce NPP), the Czech Republic (Dukovany NPP, Temelin NPP) and Hungary (Pask NPP) are presented. The leakage rate from hermetic compartments at individual NPP reactor units are shown.The VUEZ activities in field of resealing of weld joints in pools and tanks in the Jaslovske Bohunice V-1 NPP and innovation of the seal of reactor pit protective hood (kolpak) are described. The principle of operation and practical experience of the SMU-V system implemented in the Jaslovske Bohunice V-1 NPP (WWER 440 - V 230) for NPP primary circuit leakage monitoring are also given

Information letter 12. Information about operation of Jadrova vyradovacia spolocnost, a.s. and plants SE-NPP Bohunice during December 2006

International Nuclear Information System (INIS)

2007-01-01

In this leaflet results of exploitation of four units of the Bohunice V1 and V2 NPPs are presented. The electricity and heat production in December 2006 are reviewed. Within a December 2006 the electricity was produced in NPP V1: 301.221 GWh (block 1), 281.125 GWh (block 2), totally 582.346 GWh, and 6179.205 GWh within a January - December 2006. Within a November 2006 the NPP V2: the block 3 and block 4 has worked in stabile regime according to needs of regulation. Processing and storage of radioactive wastes in Jadrova vyradovacia spolocnost (JAVYS) is presented. Twenty pieces of fibre-concrete containers were processed into fibre-concrete containers in Bohunice processing centre of radioactive wastes (BSC RAO) in December 2006. Eight fibre-concrete containers were stored into Republic storage of radioactive wastes (RU RAO). Total number in RU RAO reached 1260 pieces of fibre-concrete containers, which represent 17.50 per cent of storage capacity (7200 containers)

Information letter 10. Information about operation of Jadrova vyradovacia spolocnost, a.s. and plants SE-NPP Bohunice during October 2006

International Nuclear Information System (INIS)

2006-11-01

In this leaflet results of exploitation of four units of the Bohunice V1 and V2 NPPs are presented. The electricity and heat production in October 2006 are reviewed. Within a October 2006 the electricity was produced in NPP V1: 313.778 GWh (block 1), 209.838 GWh (block 2), totally 523.616 GWh, and 5125.651 GWh within a January - October 2006. Within a October 2006 the NPP V2: blocks 3 and 4 has worked on nominal power. Processing and storage of radioactive wastes in Jadrova vyradovacia spolocnost (JAVYS) is presented. Seventeen pieces of fibre-concrete containers were processed into fibre-concrete containers in Bohunice processing centre of radioactive wastes (BSC RAO) in October 2006. Thirty-eight fibre-concrete containers were stored into Republic storage of radioactive wastes (RU RAO). Total number in RU RAO reached 1234 pieces of fibre-concrete containers, which represent 17.14 percent of storage capacity (7200 containers)

Heat delivery from Bohunice NPP, Slovakia

International Nuclear Information System (INIS)

Paley, I.

1998-01-01

Experience with nuclear district heating in the Slovak Republic is reported. The heating system of the town of Trnava is supplied by the Bohunice NPP and conventional sources. Construction of the hot water heating system from the Bohunice NPP began in 1983. Commercial operation began on 10 December 1987. Heat delivery has gradually increased from 478 TJ in 1988, to 1,104 TJ in 1995. The heat cost is low, resulting in an increasing number of consumers. (author)

Report of the IPERS (International Peer Review Service) review mission for the Bohunice-V2 nuclear power plant Level 1 probabilistic safety assessment in the Slovak Republic 17 to 28 January 1995

International Nuclear Information System (INIS)

1995-01-01

This report presents the results of the IAEA International Peer Review Services (IPERS) review of the probabilistic safety assessment (PSA) for the Bohunice-V2 NPP. The review was based on the PSA documentation available and on intensive communications with the analysis team and representatives from the utility and the plant operator. The results presented herein reflect the views of the international experts carrying out the review. They are provided for consideration by the responsible authorities of the Slovak Republic. 12 refs, 4 tabs

Internal communication at Bohunice NPPs

International Nuclear Information System (INIS)

Dobdk, Dobroslav

1999-01-01

Communication is the base of everyday existence of a modern person and every company. It is not easy to work in this area in a changing 'eastern' country. Many tools, which are used are in the mind of people connected with 'propaganda'. I would like to share our experience with you. The goal of an internal communication is to spread and provide continuous current of objective information between the management of Bohunice NPPs and its personnel and between the personnel itself. Communication with the Bohunice NPPs employees helps to get acquainted with their opinions and ideas concerning the subsidiary and nuclear power industry

Bohunice NPPs - Part of the Slovak's economy (sustainable) development

International Nuclear Information System (INIS)

Dobak, Dobroslav

2001-01-01

Of the total consumption of electricity in Slovakia, 42% was generated in nuclear power plant units in 1999. Slovakia operates 6 units with a WWER 440 nuclear reactors, 4 of them are at Bohunice site and 2 at Mochovce. The Nuclear Regulatory Authority of SR is not the only regulatory body controlling nuclear activity. Both - the system of nuclear activities regulation in Slovakia as well as the approach to Nuclear Safety enhancement of the operator were positively judged by IAEA and WENRA. In 1993 -Slovakia has accepted the commitments of the UN Convention on Climate Changes, including a reduction of greenhouse gases to 1990 levels by the year 2000. Moreover, as an internal target Slovakia has set the reaching of the ,'Toronto Objective', i.e. 20% reduction in CO x emissions through the year 2005 as compared to 1988. Taking into account the actual situation as well as natural conditions for some renewable sources utilisation, the target won't be reached without nuclear energy. The nuclear energy is free of emissions, does not burn oxygen, and with the share of production in Slovakia will remain significant contributor. To the environment protection it contributes also by replacing fossil heat plants with heat delivery for the region. In case of radiological wastes the environment protection is ensured by very strict system of control, evidence, treatment and repository. To conclude, Bohunice NPPs were, are and will remain very important part of the Slovak's economy, creating conditions for its (sustainable) development

Practical experience with the leaky-fuel monitoring at Bohunice NPP

International Nuclear Information System (INIS)

Kacmar, M.; Cizek, J.

2001-01-01

The first part of this paper describes practical experience with the fuel monitoring in operating reactors from point of view possible leakages. Summarized in the paper are numbers leaky fuel assemblies both for NPP and for particular units. Some failure causes are discussed for operational conditions of Bohunice NPP. In the second part of paper critical power ramps on hot fuel rod of leaky fuel assemblies are analysed to eliminate failures from PCI. The main aim of the paper is the need to understand the mechanism and causes of failures (Authors)

Information letter 1. Information about operation of plants SE-NPP Bohunice and SE-VYZ during January 2006

International Nuclear Information System (INIS)

2006-02-01

In this leaflet results of exploitation of four units of the Bohunice V-1 and V-2 NPPs are presented. The electricity and heat production in January 2006 are reviewed. Within a January 2006 the electricity was produced: 249.149 GWh (block 1), 293.272 GWh (block 2), 305.479 GWh (block 3), 308.378 GWh (block 4), totally 1156 GWh. The heat production in January 2006 was 354 397 GJ. Processing and storage of radioactive wastes in Decommissioning of Nuclear Installations and Spent Fuel and Rad-waste Management (SE-VYZ) is presented. Twenty-two pieces of fibre-concrete containers were processed into fibre-concrete containers in Bohunice processing centre of radioactive wastes (BSC RAO) in January 2006. Sixteen fibre-concrete containers were stored into Republic storage of radioactive wastes (RU RAO). Total number in RU RAO reached 1048 pieces of fibre-concrete containers, which represent 14.55 per cent of storage capacity (7200 containers)

Radiation supervision - NPPs A-1, V-1, V-2

International Nuclear Information System (INIS)

2000-01-01

In this leaflet the radiation supervision of the nuclear power plants A-1, V-1, V-2 is presented. Off-site radiation supervision laboratory is a part of monitoring scheme of the NPPs. More than 1150 samples are taken from the environment annually. The tele-dosimetric system was constructed to improve the quality of the Bohunice NPPs operation impacts supervision. It has been running in a continuous operation from 1992 and providing supervision of the nuclear power plant off-site area within 25 kilometres. The tele-dosimetric system is described

Chapter No.3. Assessment and inspection of nuclear installations

International Nuclear Information System (INIS)

2002-01-01

The assessment activity of UJD in relation to nuclear installation lies in assessment of safety documentation for constructions realised as nuclear installations, or construction through which changes on nuclear installations are realised. The assessment activity of UJD in 2001 was focused on National Repository of Radwaste in Mochovce, on Radwaste conditioning and treatment technology in Jaslovske Bohunice and on the assessment of documentation for the project of modernisation of Bohunice V-2 NPPs which is under preparation. The assessment of the technical condition of equipment, important in terms of nuclear safety, primarily based on results of in-service inspections and surveillance testing of safety related components and systems, is also a part of the safety assessment of nuclear installation operation. The inspectors take part in training courses and participate in other technical meetings and workshops organised by the IAEA and also take part in special training courses organised by the Nuclear Authorities of European countries, USA and Japan. Bohunice V-1 NPP is equipped with two reactors of WWER 440 type V-230 and was put into operation in 1978-1980 as one of the last nuclear power plants with this type of reactor. Both units of NPP V-1 Bohunice operated in 2001 according to the requirements of energy dispatching at nominal power, or in a regime of tertiary regulation. November 2000, a mission of experts invited by UJD and delegated by IAEA took place at the Bohunice NPPs. The mission members together with experts of the plant operator assessed the safety of the units of WWER-440/V-230 of Bohunice V-1 NPP after the reconstruction. The members of the mission prepared the report on the current status of safety of these units for the IAEA. In 2001, UJD by its decision, issued the approval for further operation of both reactor units of Bohunice V-1 NPP. In sense of the relevant decree on operational events, 20 events have been recorded, at Bohunice V-1 NPP in

Slovak Electric, plc, Bohunice Nuclear Power Plant

International Nuclear Information System (INIS)

1999-01-01

A brief account of activities carried out by the Bohunice Nuclear Power Plant in 1998 is presented. These activities are reported under the headings: (1) Operation and electric power generation; (2) Nuclear and radiation safety; (3) Maintenance and scheduled refuelling out-gages; (4) Investment and WWER units upgrading; (5) Power Plants Personnel; (6) Public relations

Analysis of events significant with regard to safety of Bohunice V-1 nuclear power plant

International Nuclear Information System (INIS)

Suchomel, J.; Maron, V.; Kmosena, J.

1986-01-01

An analysis was made of operating safety of the V-1 nuclear power plant in Jaslovske Bohunice for the years 1980 - 1983. Of the total number of 676 reported failures only three were events with special safety significance, namely a complete loss of power supply for own consumption from the power grid, a failure of pins on the collectors of steam generators, and a failure of the heads of heat technology inspection channels. The failures were categorized according to the systems used in the USSR and in the USA and compared with data on failures in nuclear power plants in the two countries. The conclusions show that the operation of the V-1 nuclear power plant achieves results which are fully comparable with those recorded in 9 WWER-440 power plants operating in various countries. The average coefficient of availability is 0.72 and ranks the power plant in the fourth place among the said 9 plants. A comparison of the individual power plant units showed that of the total number of 22, the first unit of the V-1 plant ranks fifth with a coefficient of 0.78 and the second unit with a coefficient of 0.69 ranks 15th. (Z.M.)

The NPPR Trnava participation in the NPP V-2 modernisation and safety improvement project

International Nuclear Information System (INIS)

Michal, V.; Losonsky, B.; Magdolen, J.

1999-01-01

The presented contribution deals with form, present state and results of Nuclear Power Plants Research Inst.e participation in the NPP V-2 Jaslovske Bohunice Modernization and Safety Improvement Project.(author)

The V-1 NPP and V-2 NPP upgrading

International Nuclear Information System (INIS)

1998-01-01

A brief account of activities in the V-1 NPP and V-2 NPP upgrading as well as maintenance carried out by the Nuclear power plants Jaslovske Bohunice in 1997 is presented. The V-1 NPP applied the so called 'Small Backfitting Programme'covering 81 points of the Czechoslovak Atomic energy Commission Decree No 5/91. Continual upgrading continued after the Backfitting Programme completion with the Safety Report and following Nuclear Regulatory Authority of Slovak Republic (NRA SR) Decrees No 1/94 and 110/94 setting spheres and procedure for adopting and implementation of measures enabling the units to operate further on. Results of expert missions, analyses and assessments of components identified by Basic Engineering became the basis for the development of the Gradual Reconstruction Programme. The Programme outputs underwent economic and probabilistic assessing their contribution to nuclear safety. This process resulted in finalizing the Gradual Reconstruction Programme which started to be implemented in 1996 and will be completed in 1999. It is implemented by the REKON consortium and covers 17 areas including Instrumentation and Control, self-consumption emergency supply, leakage monitoring, emergency core cooling system, seismic reinforcement and radioactivity localisation. Both units will reach internationally acceptable safety standards for the remaining life-time period. The V-2 NPP Upgrading and Safety Enhancement Programme includes results of activities performed in the course of last years to define all important activities leading to enhancement of nuclear safety and performance reliability and effectiveness within the plant life-time period and to establish conditions for extending the life-time of these units for 40 years. The V-2 NPP Upgrading and Safety Enhancement Programme aims to assure safe operation with a probability of the core damages less than 10 -4 /reactor · year

Information letter 3. Information about operation of plants SE-NPP Bohunice and SE-VYZ during March 2006

International Nuclear Information System (INIS)

2006-04-01

In this leaflet results of exploitation of four units of the Bohunice V-1 and V-2 NPPs are presented. The electricity and heat production in March 2006 are reviewed. Within a March 2006 the electricity was produced: 294.020 GWh (block 1), 287.684 GWh (block 2), 292.636 GWh (block 3), 237.806 GWh (block 4), totally 1112 GWh, and 3330 GWh within a January - March 2005. The heat production in January 2006 was 253 057 GJ, and within a January - March 2006 it was produced 896 226 GJ of heat. Processing and storage of radioactive wastes in Decommissioning of Nuclear Installations and Spent Fuel and Rad-waste Management (SE-VYZ) is presented. Twenty-one pieces of fibre-concrete containers were processed into fibre-concrete containers in Bohunice processing centre of radioactive wastes (BSC RAO) in March 2006. Sixteen fibre-concrete containers were stored into Republic storage of radioactive wastes (RU RAO). Total number in RU RAO reached 1080 pieces of fibre-concrete containers, which represent 15.00 per cent of storage capacity (7200 containers). Celebration of ten years operation of SE-VYZ is described

Information letter 6. Information about operation of GovCo, a.s. and plant SE-NPP Bohunice during June 2006

International Nuclear Information System (INIS)

2006-07-01

In this leaflet results of exploitation of four units of the Bohunice V-1 and V-2 NPPs are presented. The electricity and heat production in June 2006 are reviewed. Within a June 2006 the electricity was produced in GovCo, a.s.: 289.150 GWh (block 1), 262.103 GWh (block 2), totally 551.253 GWh, and 321.515 GWh within a January - June 2006 and in SE-EBO, NPP V2: 278.896 GWh (block 3), 0 GWh (block 4), totally 278.896 GWh, and 2778.249 GWh within a January - June 2006. The heat production in June 2006 was 38 212 GJ, and within a January - June 2006 it was produced 1 098 605 GJ of heat. Processing and storage of radioactive wastes in GovCo, a.s. - Decommissioning of Nuclear Installations and Spent Fuel and Rad-waste Management (VYZ) is presented. Thirty-two pieces of fibre-concrete containers were processed into fibre-concrete containers in Bohunice processing centre of radioactive wastes (BSC RAO) in January 2006. Sixteen fibre-concrete containers were stored into Republic storage of radioactive wastes (RU RAO). Total number in RU RAO reached 1132 pieces of fibre-concrete containers, which represent 15.72 per cent of storage capacity (7200 containers). The technique of SE-VYZ in decommissioning of A1 NPP is described

NPP Bohunice experience with ASSET services

Energy Technology Data Exchange (ETDEWEB)

Klimo, J [Bohunice NPP (Slovakia)

1997-12-31

The general description of Bohunice NPP ASSET experience history was given at the last annual workshop in 1995. In my short presentation I would like to pay attention to the progress in this area which was achieved at our NPP during the last year. (author).

NPP Bohunice experience with ASSET services

International Nuclear Information System (INIS)

Klimo, J.

1996-01-01

The general description of Bohunice NPP ASSET experience history was given at the last annual workshop in 1995. In my short presentation I would like to pay attention to the progress in this area which was achieved at our NPP during the last year. (author)

Evaluation of seismic resistance of low voltage switchgear, NPP V1 Jaslovske Bohunice, Slovakia

International Nuclear Information System (INIS)

Zeman, P.

1999-01-01

During this year, company Stevenson and Associates took part in the project of evaluation of seismic resistance of NPP V-1 Jaslovske Bohunice in Slovakia. It was responsible for a part of electrical equipment, mainly for the evaluation of low voltage switchgears. There were four steps of the evaluation: Detailed Walkdown; Application of GIP-WWER Methodology; Developing, of In Cabinet Response Spectra; and Evaluation of Acceptance of Formerly Performed Relay Tests According to the Russian Standard OEG l-330.00-3). Tests performed according to the Russian Standard OAG are acceptable only if the tested subject shows just one dominant natural frequency in the significant energy frequency range. If there is no knowledge of modal properties of the tested subject (that is a frequent situation because test reports usually contain only generalized Fourier loading spectrum) the enveloping of In Cabinet Response Spectra (ICRS) in all significant energy frequency ranges by Response Spectra (RS) of harmonic signal on one arbitrary frequency. This criteria is usually not satisfied because the shake tables used for the tests are not able to produce the sufficient level of excitation in the low frequency range. It may lead to the demand for test repeating

Progress in Investigation of WWER-440 Reactor Pressure Vessel Steel by Gamma and Moessbauer Spectroscopy

International Nuclear Information System (INIS)

Hascik, J.; Slugen, V.; Lipka, J.; Hinca, R.; Toth, I.; Groene, R.; Uvacik, P.; Kupca, L.

1998-01-01

Gamma spectroscopic analyse and first experimental results of original irradiated reactor pressure vessel surveillance specimens are discussed in. In 1994, the new ''Extended Surveillance Specimen Program for nuclear Reactor Material Study'' was started in collaboration with the nuclear power plants (NPP) V-2 Bohunice (Slovakia). The first batch of MS samples (after 1 year, which is equivalent to 5 years of loading RPV-steel) was measured and interpreted using the new four components approach with the aim to observe microstructural changes due to thermal and neutron treatment resulting from operating conditions in NPP. The systematic changes in the relative areas of Moessbauer spectra components were observed. (author)

Experiences from start-up and use of fail-safe reactor level meter with KNITU probes

International Nuclear Information System (INIS)

Badiar, S.; Sipka, J.; Vanco, P.; Slanina, Marek; Liska, L.; Gavora, D.

2001-01-01

Within the framework of the reconstruction of both V1 Bohunice units with WWER-440/V-230 reactors, the VUJE-SIEMENS consortium implemented measurement systems for coolant level monitoring in reactor pressure vessels with 1E qualification, resp. with the qualification of category 1 according to NUSS RG1.97. The solution uses KNITU 11 probes made by Russian POZIT company. In operating plants, the installation causes problems in relation to the existing technology and quality assurance system. In the phase of implementation, the most important tasks were to resolve component quality, to commission the system, and to check its performance. (Authors)

Mitsubishi nuclear technologies and construction of new Bohunice

International Nuclear Information System (INIS)

Yoshizu, T.

2009-01-01

Mitsubishi Heavy Industries (MHI) has setup Generation III+ category power plant technologies both in large and middle size reactors as a key player in the global market of nuclear plant suppliers. MHI has developed 1,700 MWe class Advanced Pressurized Water Reactor for European utilities, EU-APWR, utilizing the APWR technology in Japan. The plant configuration is based on the proven technologies from MHI's ample experiences, but various advanced technologies are adopted to achieve enhanced safety, reliability, and economy. For the regions without large grid capacity, middle-sized nuclear power plant will be an attractive option for the utilities. Joint Venture ATMEA with AREVA NP will serve ATMEA1. The ATMEA1 will offer 1,100 MWe output with superior operation performance based on reliable and proven technologies. Mitsubishi has experience of half century for all of 26 PWR plants in Japan. The latest plant is Tomari Unit 3 of 1,000 MWe, which has completed the construction work and now in the final commissioning test. Tomari Unit 3 applies some advanced technologies such as all digital I and C, which are to be implemented in the EU-APWR. Based on this construction experience, Mitsubishi can contribute any kind of demands for New Bohunice 5 th unit project with the total engineering capability. (author)

Operational experiences feedback in Bohunice NPP

Energy Technology Data Exchange (ETDEWEB)

Betak, A [NPP Bohunice (Slovakia)

1997-10-01

The presentation reviews the following issues: OEF team in Bohunice NPP - structure; training and qualification: ASSET seminars on Prevention of incidents - INES manual handling, NRA-NRC the training on event investigation methods, NU - the training on HPES; legislation - documentation prepared in the frame of QA programme; results of OEF team activities; ASSET mission Dukovany - Experiences; the perspective activities.

SEJV2 software package for radiation monitoring system of WWER 440 NPP

International Nuclear Information System (INIS)

Kapisovsky, V.; Jancik, O.; Kubik, I.; Bena, J.

1993-01-01

The main part of the radiation monitoring system at a WWER-440 (213 reactor type) nuclear power plant is the centralized 400-channel monitoring system 'SEJVAL' servicing twin reactor units. The SEJV2 software package is described developed to run on a PC with an IFS2 interface to the SEJVAL radiation monitoring system. It provides enhanced data presentation, record keeping and report generation, thus improving the efficiency of the health physics shift. The system was for the first time implemented at the Jaslovske Bohunice V-2 nuclear power plant with encouraging results. (Z.S.) 3 refs

Experience with construction and assembly of V-1 nuclear power plant

International Nuclear Information System (INIS)

Prochazka, J.; Stepanek, S.; Drahy, J.

1981-01-01

The model is discussed of the constructions of the V-1 nuclear power plant at Jaslovske Bohunice with SKODA Trust fulfilling the role of the general supplier of the secondary part technology and the chief and special assembly contractor. The SKODA Trust mediated the Soviet supplies of technology, Soviet assembly and special assembly, and the mounting of the primary part according to Soviet projects. Plant start-up was safeguarded by the investor through Bohunice power plant staff and Soviet experts. The assembly of the primary circuit and the test assembly of reactor parts are described and the experience gained is discussed. The technological requirements are illustrated by the most important characteristics of the individual parts of the primary circuit. Also described are the design specifications of the 220 MW saturated steam turbine and the experience with its assembly and start-up. (B.S.)

KS-150 reactor control

International Nuclear Information System (INIS)

Wagner, K.

1974-01-01

A thorough description is presented of the control and protection system of the Bohunice A-1 reactor. The system including auxiliary facilities was developed, manufactured and installed at the reactor by the SKODA Works, Plzen. The system parameters are listed and a brief account is also given of the development efforts and of the physical and power start-up of the A-1 nuclear power plant. (L.O.)

Nuclear safety in Slovak Republic. Safety analysis reports for WWER 440 reactors

International Nuclear Information System (INIS)

Rohar, S.

1999-01-01

Implementation of nuclear power program is connected to establishment of regulatory body for safe regulation of siting, construction, operation and decommissioning of nuclear installations. Licensing being one of the most important regulatory surveillance activity is based on independent regulatory review and assessment of information on nuclear safety for particular nuclear facility. Documents required to be submitted to the regulatory body by the licensee in Slovakia for the review and assessment usually named Safety Analysis Report (SAR) are presented in detail in this paper. Current status of Safety Analysis Reports for Bohunice V-1, Bohunice V-2 and Mochovce NPP is shown

Lessons from feedback of safety operating experience for reactor physics

International Nuclear Information System (INIS)

Suchomel, J.; Rapavy, S.

1999-01-01

Analyses of events in WWER operations as a part of safety experience feedback provide a valuable source of lessons for reactor physics. Examples of events from Bohunice operation will be shown such as events with inadequate approach to criticality, positive reactivity insertions, expulsion of a control rod from shut-down reactor, problems with reactor protection system and control rods. (Authors)

Complex nuclear safety evaluation of the Bohunice V-1 nuclear power plant

International Nuclear Information System (INIS)

Kriz, Z.

1991-01-01

The safety concept of V-230 type reactor units dates back to the late 1960s. The units fail to be sufficiently dimensioned for emergency cooling of the reactor core and are fitted with no containment. So far, operating experience is good. The availability factor is 71.5% for unit 1 and 77.8% for unit 2. There occur 1 to 3 unscheduled shutdowns annually. The quality of steam generator tubes is very good. A complex safety assessment of the plant was accomplished in 1990. It concerned the concept and criteria of safety assessment, the earthquake situation, the condition of the primary coolant circuit equipment, the control system, the effect of the human factor, and preparedness of emergency plans. OSART and ASSET missions were accomplished at the plant. Based on the results of the missions as well as of inspections by the State Surveillance over Nuclear Safety, the decision has been adopted to operate the plant not longer than till 1995; the further fate of the plant will be decided on according to a future technical and economic analysis. (M.D.)

Planning for environmental restoration of the contaminated banks near NPP Bohunice

Energy Technology Data Exchange (ETDEWEB)

Slavik, O; Moravek, J [Nuclear Power Plants Research Institute, a.s., Trnava (Slovakia); Vladar, M [Inst. of Preventive and Clinical Medicine, Bratislava (Slovakia)

1996-12-31

The 18 km long banks of the Bohunice NPP waste water recipient are contaminated by cesium-137 as a result of two accidents on the CO{sub 2} cooled NPP A{sub 1} unit in 1976 and 1977. Since 1992, all he contaminated waste waters dumping from NPP Bohunice has been carried out directly to the Vah River through a specially constructed 15 km long pipeline. The final extent of contamination in the Bohunice site is represented. The overall contaminated area in this site with cesium-137 activity above 1 Bq/g of soil is about 67000 m{sup 2} and thus, the corresponding volume of top 20 cm thick soil layer is about 13000 m{sup 3}. For optimizing less costly remedial measures (warning signs...) an agreed scenario with a pre-estimated factor factor collective dose 2.10{sup -7} man.Sv.y{sup -1}/(m{sup 2}.Bq{sup 137}Cs.g{sup -1}) was applied. Limitation of individual effective doses according to a site specific stay scenario was also considered for this purposes with a limiting value of 0.25 mSv/y. Cost analysis of available remedial techniques were carried out, too. Two techniques have been selected for the contaminated banks restoration project: 1) removing/disposal of 20 cm soil top layer from steep and unengineered banks, and 2) mechanical dilution/fixation of contamination by clean 15 cm soil cover for the contaminated flat areas. Two-fold reduction of anticipated potential radiation risk were accepted, maximally, for the lastly mentioned technique, however cost saving is considerable (about 10-time lower the cost comparing to removing/disposal technique one). The basic acceptance limits AL for {sup 137}Cs in soil and criteria size of continuously contaminated bank areas were derived as: AL{sub 200} = 6.0 Bq/g and 800 m{sup 2} (300 m) or AL{sub 50} 8.0 Bq/g and 200 m{sup 2} (80 m) for removing/disposal of the soil on steep unengineered banks. For clean soil covering technique the resulting limits are in an interval AL{sub 50C} = 8 up to 16 Bq/g. (Abstract Truncated)

Radiological characterisation of V1 NPP technological systems and buildings - Activation

International Nuclear Information System (INIS)

Kristofova, Kristina; Rapant, Tibor; Svitek, Jaroslav

2012-01-01

V1 NPP at Jaslovske Bohunice site has been finally shutdown after 28 years of successful operation in 2006 (Unit 1) and 2008 (Unit 2). At present, both units are finally shutdown and since July 2011 under decommissioning license. The preparation of V1 NPP decommissioning has been supported and partly financed by the Bohunice International Decommissioning Support Fund (BIDSF), under the administration of the European Bank for Reconstruction and Development. From 06/2008 to 12/2011 AMEC Nuclear Slovakia, together with partners STM Power and EWN GmbH, carried out BIDSF B6.4 project - Decommissioning database development (DDB). The main purpose of the B6.4 project was to develop a physical and radiological inventory database to support V1 NPP decommissioning process planning and performance. One of the specific deliverable tasks within the B6.4 project was deliverable D12 - Characterization of activated equipment and civil structures based on measurement, sampling and analyses performed on the samples. The scope of deliverable services within D12 task consisted of: 1. Categorization of activated components ; 2. Development of single working programs for their radiological monitoring and sampling ; 3. Preparation of sampling device and revision of all handling equipment; 4. Dose rate monitoring and sampling of: - Civil structures from reactors shaft on both units ; - Components placed in HLW storage, (so called 'Mogilnik') - connection rods, absorbers ; of control rod assemblies and neutron flux measurement channels ; - Reactor pressure vessel and shielding assemblies at both units of V1 NPP, reactor; internals from Unit 2 of V1 NPP; 5. Analysis of samples ; 6. Determination of radiological inventory ; 7. Import of radiological data for activated components into DDB. During sampling, mainly remotely controlled sampling device and radiation resistant camera with LED lightening for visual checking of all performed activities was used. In total, 125 samples have been taken

ASTEC applications to VVER-440/V213 reactors

Energy Technology Data Exchange (ETDEWEB)

Matejovic, Peter, E-mail: ivstt@nextra.sk; Barnak, Miroslav; Bachraty, Milan; Vranka, Lubomir

2014-06-01

Since the beginning of ASTEC development by IRSN and GRS the code was widely applied to VVER reactors. In this paper, at first specific features of VVER-440/V213 reactor design that are important from the modelling point of view are briefly described. Then the validation of ASTEC code with focus on its applicability to VVER reactors is briefly summarised and the results obtained with the ASTEC V2.0-rev1 version for the ISP-33 PACTEL natural circulation experiment are presented. In the next section the application of ASTEC V2.0-rev1 code in upgrade of VVER-440/V213 NPPs to cope with consequences of severe accidents is described. This upgrade includes adoption of in-vessel retention via external reactor vessel cooling and installation of large capacity passive autocatalytic recombiners. Results of analysis with focus on corium localisation and stabilisation inside reactor vessel, hydrogen control in confinement and prevention of long-term confinement pressurisation are presented.

Eco information 2. Influence of operation of the plants Jadrova vyradovacia spolocnost, a.s., on the environment, locality of Bohunice, within February 2016

International Nuclear Information System (INIS)

2016-03-01

In this leaflet the results of monitoring of chemical gaseous and liquid effluents into the rivers Vah and Dudvah as well as of radiation monitoring of Bohunice V1 NPP, Interim Spent Fuel Storage (MSVP), Bohunice Radioactive Waste Processing Centre (VK808 - BSC), The Main Production Unit (VK 46A - HVB) and Bitumenation Lines (VK 46B - BL) are presented. The alpha radioactive effluents into atmosphere within January - February 2016 (for NPP V1, MSVP, BSC, HVB and BL, respectively) were: 0.100 MBq (0.001 of AL) for V1, 0.013 MBq (0.004% of AL) for MSVP, 0.017 MBq (0.012% of AL) for BSC, 0.048 MBq (0.007% of AL) for HVB and 0.005 MBq (0.003% of AL) for BL of aero-soles. The radioactive effluents into atmosphere and hydrosphere within a February 2016 for NPP V1, MSVP, and VK 808 BSC, respectively, were: 0.049 MBq (V1), 0.007 MBq (VK MSVP), 0.011 MBq (VK 808 BSC), 0.020 MBq (VK 46A) and 0.002 MBq (VK 46B) of aero-soles into atmosphere; 0.706 MBq (V1 and MSVP) and 0.738 MBq (TSU RAO and NPP A1) of corrosive and fission products, and 0.419 GBq (V1 and MSVP) and 7.479 GBq (TSU RAO and NPP A1) of tritium into the Vah River and 0.000 GBq (V1 and MSVP) and 0.000 MBq (TSU RAO and NPP A1) of corrosive and fission products and 0.000 GBq of tritium (V1) and 0.000 GBq of tritium (TSU RAO and NPP A1) into the Dudvah River). For the period January - February 2016 these radioactive effluents into recipient of Vah River represent for corrosive and fission products 0.898 MBq (0.0069% of AL for V1 and MSVP) and 1.084 MBq (0.009% of AL for TSU RAO and MSVP); and for tritium it is 0.420 GBq (0.02098% of AL) for V1 and MSVP, and 18.470 GBq (0.185% of AL) for TSU RAO and NPP A1 (into the Vah River) and for corrosive and fission products 0.000 MBq (V1 and MSVP) and 0.000 MBq (TSU RAO and NPP A1) (0.0000 of AL) of tritium (into the Dudvah River). Chemical effluents are reported, too.

Material properties of Bohunice 1 and 2 reactor pressure vessel materials before and after annealing

International Nuclear Information System (INIS)

Brumovsky, M.; Novosad, P.; Vacek, M.

1994-01-01

Six types of experimental RPV materials were studied before and after irradiation in host nuclear power and research reactors. Recovery of RPV materials from radiation hardening and embrittlement after annealing was evaluated including a rate of radiation damage after reirradiation used. (author). 3 refs, 4 figs, 2 tabs

Planning for environmental restoration of the contaminated banks near NPP Bohunice

International Nuclear Information System (INIS)

Slavik, O.; Moravek, J.; Vladar, M.

1995-01-01

The 18 km long banks of the Bohunice NPP waste water recipient are contaminated by cesium-137 as a result of two accidents on the CO 2 cooled NPP A 1 unit in 1976 and 1977. Since 1992, all he contaminated waste waters dumping from NPP Bohunice has been carried out directly to the Vah River through a specially constructed 15 km long pipeline. The final extent of contamination in the Bohunice site is represented. The overall contaminated area in this site with cesium-137 activity above 1 Bq/g of soil is about 67000 m 2 and thus, the corresponding volume of top 20 cm thick soil layer is about 13000 m 3 . For optimizing less costly remedial measures (warning signs...) an agreed scenario with a pre-estimated factor factor collective dose 2.10 -7 man.Sv.y -1 /(m 2 .Bq 137 Cs.g -1 ) was applied. Limitation of individual effective doses according to a site specific stay scenario was also considered for this purposes with a limiting value of 0.25 mSv/y. Cost analysis of available remedial techniques were carried out, too. Two techniques have been selected for the contaminated banks restoration project: 1) removing/disposal of 20 cm soil top layer from steep and unengineered banks, and 2) mechanical dilution/fixation of contamination by clean 15 cm soil cover for the contaminated flat areas. Two-fold reduction of anticipated potential radiation risk were accepted, maximally, for the lastly mentioned technique, however cost saving is considerable (about 10-time lower the cost comparing to removing/disposal technique one). The basic acceptance limits AL for 137 Cs in soil and criteria size of continuously contaminated bank areas were derived as: AL 200 = 6.0 Bq/g and 800 m 2 (300 m) or AL 50 8.0 Bq/g and 200 m 2 (80 m) for removing/disposal of the soil on steep unengineered banks. For clean soil covering technique the resulting limits are in an interval AL 50C = 8 up to 16 Bq/g. According to the criteria developed, it is necessary to subject to restoration about 11000 m 2 of

SIEMENS

International Nuclear Information System (INIS)

2001-01-01

This CD is multimedia presentation of programme safety upgrading of Bohunice V1 NPP. This chapter contains information about Siemens and it participation on reconstruction of Bohunice V1 and V1 NPPs. It consists of next parts: (1) FRAMATOME ANP - worldwide activities of the FRAMATOME are presented; (2) Nuclear power engineering - present activities focus on: Upgrading and Backfitting (Siemens WWER activities since 1971); Electrical instrumentation and control systems; Fuel assemblies and related services; Reactor development and construction of new plants; (3) Safety improvement; (4) Siemens in Slovakia (activities of Siemens in Slovakia during 1993-2000 are presented); (5) More than 150-year history

Selective Leaching of aerosol particles collected by cascade impactor in the ventilation stack of NPP V1 in Jaslovske Bohunice

Energy Technology Data Exchange (ETDEWEB)

Rulik, P; Beckova, V; Bucina, I; Foltanova, S; Poliak, R [National Radiation Protection Institute, Prague (Czech Republic)

1996-12-31

The study was apart of investigation of the size distribution of aerosol in air effluents from NPP V1 Jaslovske Bohunice. The evaluation the possible relationship between aerodynamic diameter of aerosol particles and chemical forms of radionuclides attached to the discharged aerosol was tried. Selective leaching was used for speciation of radionuclides present in the aerosol particles and for the estimation of their behaviour in the environment and absorption in gastro-intestinal tract. Activity concentrations of the radionuclides in the air, collected on collection substrates taken from individual impact stages and on back-up filter, were determined by sensitive gamma-spectrometric analysis using high purity Ge detectors. For the individual groups seven leaching steps were used. Following 12 radionuclides: silver-110m, cobalt-58, cobalt-60, cesium-134, cesium-137, manganese-54, ruthenium-103, antimony-124, antimony-125, tin-113, zinc-65, zirconium-95. Result shows that the leached fraction of the of the activity concentration does not depend on the size of the aerosol particles. (J.K.) 3 tabs., 3 figs.

Proceedings of the 9th NUSIM 2000 Conference. Joint Slovak, Czech and German Seminar on Nuclear Power

International Nuclear Information System (INIS)

2000-01-01

Scientific conference deals with problems of reactor safety upgrading, mainly of two blocks of the NPP V-1 Bohunice as well as decomissioning of the NPP A-1 Bohunice. Other problems of the nuclear engineering were discussed. Totally, 201 participants from the Slovak Republic, Czech Republic and Germany and from other countries took part in the conference. The Conference included the following sessions: (i): Survey on the situation of nuclear power in the partner countries; (ii) Mochovce design safety enhacement and operational experience; (iii) Bohunice V-1 safety upgrading and operational experience; (iv) Decomissioning, spent fuel and radwaste management; (v) Young Generation Presentation. Proceedings contains thirty one papers dealing with the scope of INIS

Analysis of the mortality development of the population in the surroundings of Bohunice NPP using Fuzzy logic methods

International Nuclear Information System (INIS)

Letkovicova, M.; Durov, M.; Stehlikova, B.

2001-01-01

We pursue the vicinity of Bohunice NPP. The vicinity has cyclic form with radius of 30 km, what represents an area approximately 2 800 km 2 . This area of pursued vicinity is requisite by the security report of Bohunice NPP. To the presumptive calculations we used the complete databases of Register of death, Register of municipalities and of Register of age structure of the inhabitants of the Slovak republic from 1993 to 1999, fully-fashioned in Statistical authority of the Slovak republic. We work with databases, which don't contain personal identifications. We pursue the evolution of the mortality by the indicators of the mortality, calculated by the WHO. By the literary sources and by our experience is necessary the sum at least of three years to calculation of stable demographic and epidemiological parameters. Therefore we work with the method of short time series. The basic observed unit, which is represented by one value of the indicator, is one municipality. All our assessing analyses are calculated from triennial sums of all indicators, so we work with man-years. Advanced report is the adjusted extract from Complex report on situation of environment and health of the inhabitants in vicinity of Bohunice NPP in 1999, which was advanced by our society in March 2001. (authors)

Welding electrode for peripheral welds of A-1 reactor pressure vessel

International Nuclear Information System (INIS)

Lakatos, L.

1975-01-01

The properties are outlined of the VUZ-AC1-52 welding electrode used in welding the Bohunice A-1 reactor pressure vessel. The mechanical properties of welded joints after the final thermal treatment are summed up. (J.K.)

Personnel education and training at Bohunice NPP

International Nuclear Information System (INIS)

Malovec, J.

1998-01-01

Procedure for education and training of all the personnel employed at Bohunice Nuclear power plant is presented in detail describing the training system structure, kinds of training, staff members qualification development, short term and long term tasks needed to assure attaining the training objectives. The proposed Staff Members Lifetime education implementation project contains basic starting points, measures to be implemented by 1998. It was prepared on the basis of a primary analysis which confirmed the existing need for implementing the lifetime education system

Computer modelling the potential benefits of amines in NPP Bohunice secondary circuit

International Nuclear Information System (INIS)

Fountain, M.J.; Smiesko, I.

1998-01-01

The use of computer modelling of PWR and WWER secondary circuit chemistry was already demonstrated in the past. The model was used to illustrate the technical and economic advantages, compared with ammonia, of using an 'advanced', high basicity, low volatility amines to raise the liquid phase pH(T) in the moisture separator and other areas swept by wet steam. Since the 1995, this technique has been successfully applied to a number of power plants and the computer model has been progressively developed. This paper describes the preliminary results of an ongoing assessment being carried out for the VVER 440 plants at Bohunice. The work for Bohunice is being funded by the 'Know How Fund', a department in the British Government's Foreign and Commonwealth Office. (J.P.N.)

Reconstruction of instrumentation and control system (SKR)

International Nuclear Information System (INIS)

Wiening, K.-H.

2001-01-01

For the first time extensive upgrades have been performed in all safety related areas of units with WWER 440/230 reactors. One of the most important actions was the replacement of the safety and safety related instrumentation and control. The state of the art digital safety instrumentation and control system TELEPERM XS has been implemented in units 1 and 2 of the Bohunice V1 power plant. The requirements as deduced from safety assessments conducted by commissions of international experts have been fulfilled, so that Bohunice V1 after this gradual reconstruction has been upgraded to an internationally accepted safety level for the remainder of its service life. (author)

Cooperation of nuclear reactor controller ARM-5S and turbine TVER-02

International Nuclear Information System (INIS)

Wagner, K.; Lnenicka, B.; Pokorny, F.; Prochazka, F.

1985-01-01

Turbines of Czechoslovak make provided with controllers TVER-02 are installed in WWER-440 nuclear power plants under construction in Czechoslovakia. Reactor output is controlled using Soviet-made controllers ARM-5S which already comprise turbine controllers. The problems are analyzed of cooperation of both controllers, especially their parameters and transient processes in typical operating situations. The analysis uses the results of measurements performed during the power start-up of Unit 1 of the V-2 nuclear power plant at Jaslovske Bohunice. The results show that two types of control modes can be selected for the operation of the entire unit: the control to constant unit output, and control of unit output varying with turbine load selected on the TVER-02 controller or given by the demand of the power network. (Z.M.)

The performance of ENDF/B-V.2 nuclear data for fast reactor calculations

International Nuclear Information System (INIS)

Atkinson, C.A.; Collins, P.J.

1987-01-01

Calculations with ENDF/B-V.2 data have been made for twenty-five fast-spectrum integral assemblies covering a wide range of sizes and compositions. Analysis was done by transport codes with refined cross section processing methods and detailed reactor modelling. The predictions of fission rate distributions and control rod worths were emphasized for the more prototypic benchmark cores. The results show considerable improvements in agreement with experiment compared with analysis using ENDF/B-IV data, but it is apparent that significant errors remain for fast reactor design calculations

Irradiation Embrittlement Monitoring Programs of RPV's in the Slovak Republic NPP's

International Nuclear Information System (INIS)

Kupca, Ludovik

2006-01-01

Four types of surveillance programs were (are) realized in Slovak NPP's: 'Standard Surveillance Specimen Program' (SSSP) was finished in Jaslovske Bohunice V-2 Nuclear Power Plant (NPP) Units 3 and 4, 'Extended Surveillance Specimen Program' (ESSP), was prepared for Jaslovske Bohunice NPP V-2 with aim to validate the SSSP results, For the Mochovce NPP Unit 1 and 2 was prepared completely new surveillance program 'Modern Surveillance Specimen Program' (MSSP), based on the philosophy that the results of MSSP must be available during all NPP service life, For the Bohunice V-1 NPP was finished 'New Surveillance Specimen Program' (NSSP) coordinated by IAEA, which gave arguments for prolongation of service life these units for minimum 20 years, New Advanced Surveillance Specimen Program (ASSP) for Bohunice V-2 NPP (units 3 and 4) and Mochovce NPP (units 1, 2) is approved now. ASSP is dealing with the irradiation embrittlement of heat affected zone (HAZ) and RPV's austenitic cladding, which were not evaluated till this time in surveillance programs. SSSP started in 1979 and was finished in 1990. ESSP program started in 1995 and will be finished in 2007, was prepared with aim of: increasing of neutron fluence measurement accuracy, substantial improvement the irradiation temperature measurement, fixed orientation of samples to the centre of the reactor core, minimum differences of neutron dose for all the Charpy-V notch and COD specimens, the dose rate effect evaluation. In the year 1996 was started the new surveillance specimen program for the Mochovce RPV's unit-1 and 2, based on the fundamental postulate - to provide the irradiation embrittlement monitoring till the end of units operation. The 'New Surveillance Specimen Program' (NSSP) prepared in the year 1999 for the Bohunice V-1 NPP was finished in the year 2004. Main goal of this program was to evaluate the weld material properties degradation due to the irradiation and recovery efficiency by annealing too. The

Liquid concrete mixes for V-2 nuclear power plant at Jaslovske Bohunice

International Nuclear Information System (INIS)

Valenta, D.; Oravec, J.

1983-01-01

The liquid concrete mixes consist of aggregates, cement, water and plastifiers. The main component of aggregates is redeposited dolomite from the Dolinka locality and sand. Cement of the SPC-325 type is used while mixing water is taken from the service water pump station for the V-1 nuclear power plant. All concretes used for the V-2 nuclear power plant construction are treated using plastifier Plastifikator S. In concrete mix development, care was primarily taken to select sand with sufficient amounts of grain of a size up to 0.25 mm. Granularity curves of the sands and the resulting curve of the aggregates granularity of the concrete mix are shown graphically. The method of manufacture and conveying of concrete mixes are briefly described. The mathematical statistical analysis of the quality of the concrete mixes produced showed that the proposed concrete mixes meet the requirements for homogeneity in the controlled parameters and that they can be manufactured in the situation of building production provided suitable components are selected, suitable aggregates are available and the quality of production is systematically checked. (J.P.)

Fuel utilization experience in Bohunice NPP and regulatory requirements for implementation of progressive fuel management strategies

Energy Technology Data Exchange (ETDEWEB)

Patenyi, V [Nuclear Regulatory Authority, Bratislava (Slovakia); Darilek, P; Majercik, J [Vyskumny Ustav Jadrovych Elektrarni, Trnava (Slovakia)

1994-12-31

The experience gained in fuel utilization and the basic requirements for fuel licensing in the Slovak NPPs is described. The original project of WWER-440 reactors supposes 3-year fuel cycle with cycle length of about 320 full power days (FPD). Since 1984 it was reduced to 290 FPD. Based on the experience of other countries, a 4-year fuel cycle utilization started in 1987. It is illustrated with data from the Bohunice NPP units. Among 504 fuel assemblies left for the fourth burnup cycle no leakage was observed. The mean burnup achieved in the different units varied from 33.1 to 38.5 Mwd/kg U. The new fuel assemblies used are different from the recent ones in construction, thermohydraulics, water-uranium ratio, enrichment and material design. To meet the safety criteria, regulatory requirements for exploitation of new fuel in WWER-440 were formulated by the Nuclear Regulatory Authority of Slovak Republic. 1 tab., 5 refs.

Monitoring of activity of the persons and vehicles at the exit from the NPP Bohunice

International Nuclear Information System (INIS)

Dobis, L.; Kaizer, J.; Svitek, J.

1998-01-01

In this paper the technical description of the monitoring of activity of the persons and vehicles at the exit from the NPP Bohunice as well as the results of monitoring during last six months are described

Eco information 4 Influence of operation of the plants Jadrova vyradovacia spolocnost, a.s., on the environment, locality of Bohunice, within April 2016

International Nuclear Information System (INIS)

2016-05-01

In this leaflet the results of monitoring of chemical gaseous and liquid effluents into the rivers Vah and Dudvah as well as of radiation monitoring of Bohunice V1 NPP, Interim Spent Fuel Storage (MSVP), Bohunice Radioactive Waste Processing Centre (VK808 - BSC), The Main Production Unit (VK 46A - HVB) and Bitumenation Lines (VK 46B - BL) are presented. The alpha radioactive effluents into atmosphere within January - April 2016 (for NPP V1, MSVP, BSC, HVB and BL, respectively) were: 0.141 MBq (0.0002 of AL) for V1, 0.027 MBq (0.006% of AL) for MSVP, 0.029 MBq (0.016% of AL) for BSC, 0.127 MBq (0.015% of AL) for HVB and 0.009 MBq (0.006% of AL) for BL of aero-soles. The radioactive effluents into atmosphere and hydrosphere within a April 2016 for NPP V1, MSVP, and VK 808 BSC, respectively, were: 0.017 MBq (V1), 0.008 MBq (VK MSVP), 0.006 MBq (VK 808 BSC), 0.029 MBq (VK 46A) and 0.003 MBq (VK 46B) of aero-soles into atmosphere; 0.880 MBq (V1 and MSVP) and 0.397 MBq (TSU RAO and NPP A1) of corrosive and fission products, and 0.315 GBq (V1 and MSVP) and 7.163 GBq (TSU RAO and NPP A1) of tritium into the Vah River and 0.000 GBq (V1 and MSVP) and 0.000 MBq (TSU RAO and NPP A1) of corrosive and fission products and 0.000 GBq of tritium (V1) and 0.000 GBq of tritium (TSU RAO and NPP A1) into the Dudvah River). For the period January - April 2016 these radioactive effluents into recipient of Vah River represent for corrosive and fission products 2.658 MBq (0.0204% of AL for V1 and MSVP) and 1.744 MBq (0.015% of AL for TSU RAO and MSVP); and for tritium it is 0.736 GBq (0.03679% of AL) for V1 and MSVP, and 31.833 GBq (0.318% of AL) for TSU RAO and NPP A1 (into the Vah River) and for corrosive and fission products 0.000 MBq (V1 and MSVP) and 0.000 MBq (TSU RAO and NPP A1) (0.0000 of AL) of tritium (into the Dudvah River). Chemical effluents are reported, too.

Research on V and V strategy of reactor physics code of COSINE

International Nuclear Information System (INIS)

Liu Zhanquan; Chen Yixue; Yang Chao; Dang Halei

2013-01-01

Verification and validation (V and V) is very important for the software quality assurance. Reasonable and efficient V and V strategy can achieve twice the result with half the effort. Core and system integrated engine for design and analysis (COSINE) software package contains three reactor physics codes, the lattice code (LATC), the core simulator (CORE) and the kinetics code (KIND), which is called the reactor physics subsystem. The V and V strategy for the physics subsystem was researched based on the foundation of scientific software's V and V method. The module based verification method and the function based validation method were proposed, composing the physical subsystem V and V strategy of COSINE software package. (authors)

VUJE experience with large scale projects and their applicability to the future of the Slovak energy system

International Nuclear Information System (INIS)

Ferenc, M.

2004-01-01

In this presentation author deals with participation of VUJE Trnava, Inc. on the reconstruction of the Bohunice V1 NPP, on modernisation of the Bohunice V2 NPP, and on of the projects in nuclear energy industry including of decommissioning of the Bohunice A1 NPP

Programmes design for Bohunice NPP personnel other than control room operators

International Nuclear Information System (INIS)

Kalincik, L.

2002-01-01

This paper deals with project development of training programmes for non-licenced NPP personnel-masters, field operators, maintenance and technical supporting personnel. The programme development focuses on the part stage and on the job training at NPP. Bohunice NPP belongs to plants with higher specific number of personnel per installed power capacity. This factor also influenced the choice of programmes design. Undermentioned procedure is one of various approaches to SAT exploitation for training programmes design. (author)

Statistical analysis of the vibration loading of the reactor internals and fuel assemblies of reactor units type WWER-440 from deferent projects

International Nuclear Information System (INIS)

Ovcharov, O.; Pavelko, V.; Usanov, A.; Arkadov, G.; Dolgov, A.; Molchanov, V.; Anikeev, J.; Pljush, A.

2006-01-01

In this paper the following items have been presented: 1) Vibration noise instrument channels; 2) Vibration loading characteristics of control assemblies, internals and design peculiarities of internals of WWER-440 deferent projects; 3) Coolant flow rate through the reactor, reactor core, fuel assemblies and control assemblies for different projects WWER-440 and 4) Noise measurements of coolant speed per channel. The change of auto power spectrum density of absolute displacement detector signal for the last 12 years of SUS monitoring of the Kola NPP unit 2; the coherence functions groups between two SPND of the same level for the Kola NPP unit 1; the measured coolant flow rate at Paks NPP and the auto power spectrum density group of SPND signals from 11 neutron measuring channels of the Kola NPP unit 1 are given. The main factors of vibration loading of internals and fuel assemblies for Kola NPP units 1-4, Bohunice NPP units 1 and 2 and Novovoronezh NPP units 3 and 4 are also discussed

NPP Mochovce - a project of extraordinay significance

International Nuclear Information System (INIS)

Chwolik, I.; Debru, M.

2000-01-01

In this paper and in this presentation the reactor safety upgrading of two blocks of the NPP V-1 Bohunice, some results of participation on safety upgrading by the German-French consortium EUCOM (Framatome and Siemens-KWU) are presented. (author)

IAEA Operational Safety Team Review Bohunice Nuclear Power Plant, Slovak Republic

International Nuclear Information System (INIS)

2010-01-01

Full text: An international team of nuclear installation safety experts, led by the International Atomic Energy Agency (IAEA), has reviewed Slovakia's Bohunice Nuclear Power Plant (BNPP) for its safety practices and has noted a series of good practices as well as recommendations to reinforce them. The IAEA assembled an international team of experts at the request of the Government of Slovak Republic to conduct an Operational Safety Review (OSART) of Bohunice NPP. Under the leadership of the IAEA's Division of Nuclear Installation Safety, the OSART team performed an in-depth operational safety review from 1 to 18 November 2010. The team was made up of experts from Belgium, Canada, China, the Czech Republic, France, Sweden, the United Kingdom and the IAEA. An OSART mission is designed as a review of programmes and activities essential to operational safety. It is not a regulatory inspection, nor is it a design review or a substitute for an exhaustive assessment of the plant's overall safety status. The team at BNPP conducted an in-depth review of the aspects essential to the safe operation of the NPP, which largely is under the control of the site management. The conclusions of the review are based on the IAEA's Safety Standards and proven good international practices. The review covered the areas of Management, Organization and Administration; Operations; Maintenance; Technical Support; Operating Experience; Radiation Protection; Chemistry and Emergency Planning and Preparedness. Long Term Operation assessment has been requested by the plant in addition to the standard OSART program. The OSART team has identified good plant practices which will be shared with the rest of the nuclear industry for consideration of their application. Examples include: BNPP has implemented a comprehensive set of technical and organizational measures which have significantly reduced the production of liquid radioactive waste; BNPP has developed an automatic transfer of dosimetry data

A three-dimensional transient calculation for the reactor model RAMONA using the COMMIX-2(V) code

International Nuclear Information System (INIS)

Weinberg, D.; Frey, H.H.; Tschoeke, H.

1993-01-01

The safety graded decay heat removal system of the European Fast Reactor needs a high availability. This system operates entirely under natural convection. To guarantee a proper design, experiments are carried out to verify thermal-hydraulic computer codes able to predict precisely local temperature loadings of the components and the reactor tank in the transition region from nominal operation under forced convection to the decay heat removal operation. - With the COMMIX-2 (V) code three-dimensional transient calculations have been performed to simulate experiments in the 360 deg. reactor model RAMONA, scaled 1:20 to the reality with water as simulant fluid for sodium. The computed average and local temperatures as well as the velocity distributions show a good agreement with the experimental results. Further efforts are necessary to reduce the computation time. (orig.)

ASTEC V2 severe accident integral code main features, current V2.0 modelling status, perspectives

International Nuclear Information System (INIS)

Chatelard, P.; Reinke, N.; Arndt, S.; Belon, S.; Cantrel, L.; Carenini, L.; Chevalier-Jabet, K.; Cousin, F.; Eckel, J.; Jacq, F.; Marchetto, C.; Mun, C.; Piar, L.

2014-01-01

The severe accident integral code ASTEC, jointly developed since almost 20 years by IRSN and GRS, simulates the behaviour of a whole nuclear power plant under severe accident conditions, including severe accident management by engineering systems and procedures. Since 2004, the ASTEC code is progressively becoming the reference European severe accident integral code through in particular the intensification of research activities carried out in the frame of the SARNET European network of excellence. The first version of the new series ASTEC V2 was released in 2009 to about 30 organizations worldwide and in particular to SARNET partners. With respect to the previous V1 series, this new V2 series includes advanced core degradation models (issued from the ICARE2 IRSN mechanistic code) and necessary extensions to be applicable to Gen. III reactor designs, notably a description of the core catcher component to simulate severe accidents transients applied to the EPR reactor. Besides these two key-evolutions, most of the other physical modules have also been improved and ASTEC V2 is now coupled to the SUNSET statistical tool to make easier the uncertainty and sensitivity analyses. The ASTEC models are today at the state of the art (in particular fission product models with respect to source term evaluation), except for quenching of a severely damage core. Beyond the need to develop an adequate model for the reflooding of a degraded core, the main other mean-term objectives are to further progress on the on-going extension of the scope of application to BWR and CANDU reactors, to spent fuel pool accidents as well as to accidents in both the ITER Fusion facility and Gen. IV reactors (in priority on sodium-cooled fast reactors) while making ASTEC evolving towards a severe accident simulator constitutes the main long-term objective. This paper presents the status of the ASTEC V2 versions, focussing on the description of V2.0 models for water-cooled nuclear plants

Assessment of the integrity of WWER type reactor pressure vessels

International Nuclear Information System (INIS)

Brumovsky, M.

1995-01-01

Procedures are given for the assessment of the residual lifetime of reactor pressure vessels with respect to a sudden failure, the lifetime of vessels with defects disclosed during in-service inspections, and the fatigue or corrosion-mechanical lifetime. Also outlined are the ways of assessing the effects of major degradation mechanisms, i.e. radiation embrittlement, thermal aging, and fatigue damage, including the use of calculated values and experimental examination, by means of surveillance specimens in particular. All results of assessment performed so far indicate that the life of reactor pressure vessels at the Dukovany, Jaslovske Bohunice, and Temelin nuclear power plants is well secured. 7 figs., 3 refs

Principles and criteria for environmental restoration of the contaminated banks near NPP Bohunice

International Nuclear Information System (INIS)

Slavik, O.; Moravek, J.

1995-01-01

The 18 km long banks of the Bohunice NPP waste water recipient are contaminated by 137 Cs as a result of two accidents on the CO 2 cooled NPP-A1 unit in 1976 and 1977. Contamination acceptance limits 6 or 8 Bq 137 Cslg of soil, depending on contaminated area size, were derived on the basis of developed principles, and approved by the authorities. Removing and safe burial of 1,100 m 3 of contaminated soil from steep area and 15 cm thick clean soil covering on about 1ha of flat area of the contaminated banks is planned in frame of the re-considered restoration project implementation in 1995/96. (author)

Environment monitoring and residents health condition monitoring of nuclear power plant Bohunice region

International Nuclear Information System (INIS)

Letkovicova, M.; Rehak, R.; Stehlikova, B.; Celko, M.; Hraska, S.; Klocok, L.; Kostial, J.; Prikazsky, V.; Vidovic, J.; Zirko, M.; Beno, T.; Mitosinka, J.

1998-01-01

The report contents final environment evaluation and selected characteristic of residents health physics of nuclear power plant Bohunice region. Evaluated data were elaborated during analytical period 1993-1997.Task solving which results are documented in this final report was going on between 1996- 1998. The report deals in individual stages with the following: Information obtaining and completing which characterize demographic situation of the area for the 1993-1997 period; Datum obtaining and completing which contain selected health physics characteristics of the area residents; Database structures for individual data archiving from monitoring and collection; Brief description of geographic information system for graphic presentation of evaluation results based on topographic base; Digital mapping structure description; Results and evaluation of radionuclide monitoring in environment performed by Environmental radiation measurements laboratory by the nuclear power plant Bohunice for the 1993-1997 period. Demographic situation evaluation and selected health physics characteristics of the area of nuclear power plant residents for the 1993-1997 period are summarized in the final part of the document. Monitoring results and their evaluation is processed in graph, table, text description and map output forms. Map outputs are processed in the geographic information system Arc View GIS 3.0a environment

Results of trial operation of new generation assemblies with improved vibration stability for WWER-440 reactors of V-230 and V-213 plants

International Nuclear Information System (INIS)

Vasilchenko, I.; Lushin, V.; Shumeev, A.

2006-01-01

FAs, in the region of FA-and-absorber rod butt joint due to arrangement of hafnium plates in the upper part of FA casing was also solved. The correctness of solutions, laid down in the design of the new generation fuel assemblies, is successfully confirmed by the results of trial operation. It is planned to apply the new generation fuel for WWER-440 reactors of V-213 type at power units of Dukovany NPP in 2005, and in 2006 at Mochovce NPP and at Bohunice NPP V-2 units 3 and 4. In 2007 it is planned to extend an application of vibration-proof working assemblies of new generation for power units of V-230 type at Kola NPP Unit 1

Eco information 9. Influence of operation of the plants Jadrova vyradovacia spolocnost, a.s., on the environment, locality of Bohunice, within September 2014

International Nuclear Information System (INIS)

2014-10-01

In this leaflet the results of monitoring of chemical gaseous and liquid effluents into the rivers Vah and Dudvah as well as of radiation monitoring of Bohunice V1 NPP, Interim Spent Fuel Storage (MSVP), Bohunice Radioactive Waste Processing Centre (VK808 - BSC), The Main Production Unit (VK 46A - HVB) and Bitumenation Lines (VK 46B - BL) are presented. The radioactive effluents into atmosphere within January - September 2014 (for NPP V1, MSVP, BSC, HVB and BL, respectively) were: 1.483 MBq (0.002 of AL) for V1, 0.087 MBq (0.029% of AL) for MSVP, 0.084 MBq (0.060% of AL) for BSC, 0.400 MBq (0.061% of AL) for HVB and 0.028 MBq (0.020% of AL) for BL of aero-soles. The radioactive effluents into atmosphere and hydrosphere within a September 2014 for NPP V1, MSVP, and VK 808 BSC, respectively, were: 0.258 MBq (V1), 0.007 MBq (VK MSVP), 0.018 MBq (VK 808 BSC), 0.005 MBq (VK 46A) and 0.002 MBq (VK 46B) of aero-soles into atmosphere; 1.169 MBq (V1 and MSVP) and 0.522 MBq (TSU RAO and NPP A1) of corrosive and fission products, and 0.002 GBq (V1 and MSVP) and 16.740 GBq (TSU RAO and NPP A1) of tritium into the Vah River and 0.000 GBq (V1 and MSVP) and 0.000 MBq (TSU RAO and NPP A1) of corrosive and fission products and 0.000 GBq of tritium (V1) and 0.000 GBq of tritium (TSU RAO and NPP A1) into the Dudvah River). For the period January - September 2014 these radioactive effluents into recipient of Vah River represent for corrosive and fission products 12.402 MBq (0.095% of AL for V1 and MSVP) and 5.010 MBq (0.042% of AL for TSU RAO and MSVP); and for tritium it is 8.382 GBq (0.419% of AL) for V1 and MSVP, and 98.415 GBq (0.984% of AL) for TSU RAO and NPP A1 (into the Vah River) and for corrosive and fission products 0.000 MBq (V1 and MSVP) and 0.000 MBq (TSU RAO and NPP A1) (0.0000 of AL) of tritium (into the Dudvah River). Chemical effluents are reported, too.

Eco information 1. Influence of operation of the plants Jadrova vyradovacia spolocnost, a.s., on the environment, locality of Bohunice, within January 2016

International Nuclear Information System (INIS)

2016-02-01

In this leaflet the results of monitoring of chemical gaseous and liquid effluents into the rivers Vah and Dudvah as well as of radiation monitoring of Bohunice V1 NPP, Interim Spent Fuel Storage (MSVP), Bohunice Radioactive Waste Processing Centre (VK808 - BSC), The Main Production Unit (VK 46A - HVB) and Bitumenation Lines (VK 46B - BL) are presented. The alpha radioactive effluents into atmosphere within January 2016 (for NPP V1, MSVP, BSC, HVB and BL, respectively) were: 0.051 MBq (0.0001 of AL) for V1, 0.006 MBq (0.002% of AL) for MSVP, 0.007 MBq (0.005% of AL) for BSC, 0.027 MBq (0.004% of AL) for HVB and 0.003 MBq (0.002% of AL) for BL of aero-soles. The radioactive effluents into atmosphere and hydrosphere within a January 2016 for NPP V1, MSVP, and VK 808 BSC, respectively, were: 0.051 MBq (V1), 0.006 MBq (VK MSVP), 0.007 MBq (VK 808 BSC), 0.027 MBq (VK 46A) and 0.003 MBq (VK 46B) of aero-soles into atmosphere; 0.192 MBq (V1 and MSVP) and 0.346 MBq (TSU RAO and NPP A1) of corrosive and fission products, and 0.001 GBq (V1 and MSVP) and 10.991 GBq (TSU RAO and NPP A1) of tritium into the Vah River and 0.000 GBq (V1 and MSVP) and 0.000 MBq (TSU RAO and NPP A1) of corrosive and fission products and 0.000 GBq of tritium (V1) and 0.000 GBq of tritium (TSU RAO and NPP A1) into the Dudvah River). For the period January - January 2016 these radioactive effluents into recipient of Vah River represent for corrosive and fission products 0.192 MBq (0.0015% of AL for V1 and MSVP) and 0.346 MBq (0.003% of AL for TSU RAO and MSVP); and for tritium it is 0.001 GBq (0.00003% of AL) for V1 and MSVP, and 10.991 GBq (0.110% of AL) for TSU RAO and NPP A1 (into the Vah River) and for corrosive and fission products 0.000 MBq (V1 and MSVP) and 0.000 MBq (TSU RAO and NPP A1) (0.0000 of AL) of tritium (into the Dudvah River). Chemical effluents are reported, too.

Production of iron-serpentinite concrete and mortar for Jaslovske Bohunice V-2 nuclear power plant

International Nuclear Information System (INIS)

Valenta, D.; Oravec, J.

1982-01-01

The ideas behind the research and the results of the research of serpentinite concrete with a discontinuous granulometric curve are given. Concrete mixes were experimentally tested; a formula is given for the manufacture of 1 m 3 of fresh concrete. Serpentinite concrete of a density of 2,240 kg/m 3 is satisfactory as shielding material. Time dependence of workability was also tested. It was found that the concrete was well workable as late as 2 hours after manufacture. Serpentinite concrete and mortar were made and used for the biological shielding construction in the shaft of Unit I of the V-2 nuclear power plant. (J.P.)

VUJE Trnava, Inc. - Engineering, Design and Research Organisation

International Nuclear Information System (INIS)

2001-01-01

This CD is multimedia presentation of programme safety upgrading of Bohunice V1 NPP. This chapter contains information about VUJE: It consists of next parts: (1) From VUJE history (1977-2001); (2) Human resources (Development of staff; Structure of employees 1999); (3) VUJE activities: (Diagnostics; Nuclear safety; Radiation safety; Commissioning and operation; Personnel training; Information technology; Electric grids; Conventional power); (4) Significant projects of VUJE are presented: Gradual reconstruction with safety upgrading of the V1 Bohunice nuclear power plant; Modernization of the V2 Bohunice NPP; Completion of the Republic Repository of Radioactive Wastes in Mochovce; Decommissioning of the A1 NPP Bohunice; Development of simulators; Physical and power commissioning of NPPs; Construction of high voltage line Varin - Sucany

The common project for completion of Bubbler Condenser Qualification (Bohunice, Mochovce, Dukovany and Paks NPPs)

International Nuclear Information System (INIS)

Jaroslav, H.; Pavol, B.

2003-01-01

Described is the common project for completion of bubbler condenser qualification for nuclear power plants in Bohunice, Mochovice, Dukovany and Paks. Functionality of the bubbler condenser was elaborated during the simulation of the main steam line brake, medium break and small break LOCA. On this basis the appropriate operation of bubbler condenser containment under accident conditions can be positively confirmed

Study air ingress into the reactor vessel using ICARE/CATHARE V2.0 in case of severe accident

International Nuclear Information System (INIS)

Gwenaelle Le Dantec; Fichot, F.

2005-01-01

Full text of publication follows: Safety analyses show that core degradation during a severe reactor accident would not be uniform. This was confirmed by TMI2 examinations. In fact, a central region of the core may overheat, melt and flow down to the lower plenum of the reactor while peripheral regions of the core would remain almost intact. Following rupture of the vessel by molten debris, air may be drawn from the containment by natural convection into the reactor coolant system, and react with the intact rods. Studying air ingress into the reactor vessel is of interest because the interaction of air with Zircaloy cladding can strongly affect the evolution of severe accident scenarios. The main effects are heat generation, increasing clad degradation, fission product release and nitriding. In case of air/steam recirculation in the vessel, significant nitriding of cladding can occur. The resulting ZrN phase is characterized by its brittleness and instability under oxidizing conditions, Oxidation of pre-existing ZrN phase layers has been observed to result in violent oxidation and heat release. Therefore, the first consequence for safety is a risk of strong deflagration in the vessel if a large number of rods on which a substantial layer of ZrN has grown are suddenly in contact with oxygen or steam. The second consequence is a late melting of core materials due to the very exothermic oxidation, leading to a late release of materials out of the reactor pressure vessel (RPV). In this paper we present an ICARE/CATHARE V2.0 calculation simulating air ingress into the vessel and in particular to describe the nitriding due to natural convection in the reactor vessel. The basic modeling and the necessary extensions of both ICARE and CATHARE are explained. The natural circulation is calculated to predict the regions of oxygen starvation where nitriding takes place. Key words: air ingress, nitriding, ICARE/CATHARE V2.0. (authors)

Treatment and conditioning of solid and liquid raw

International Nuclear Information System (INIS)

Jakubec, R.

2015-01-01

Jadrova a vyradovacia spolocnost, a.s. (JAVYS) implements activities within the processes of treatment and conditioning of radioactive waste (RAW) at two nuclear facilities, one of them located in Bohunice - Technologies for treatment and conditioning of RAW. This nuclear facility includes: Bohunice RAW treatment centre, bituminization lines, waste water purification station and technologies for sorting, fragmentation and decontamination of metallic RAW. The Bohunice RAW treatment centre (BRTC) in Bohunice processes and conditions liquid and solid radioactive waste produced during the A1 NPP and V1 NPP decommissioning, waste from the operation of V2 NPP in Bohunice as well as from the operation of NPP EMO 1,2 in Mochovce. The BRTC includes the following technological facilities: sorting, high-pressure compaction, incineration, concentration and cementation. Treatment of radioactive wastes in the BRTC is described. (authors)

Long-term measurement with calorimetric probes at unit 1 of V-1 nuclear power plant

International Nuclear Information System (INIS)

Erben, O.; Szasz, Z.; Jirousek, V.; Teren, S.

1989-01-01

Two calorimetric probes were tested at the first unit of the Bohunice V-1 nuclear power plant in long-term operation, i.e., during one whole reactor duty time. Each probe consisted of five fission calorimeters and one compensation calorimeter with a tungsten body. The actual calorimeters were provided with jacketed thermocouples 0.5 mm indiameter and 19 m in length. A detailed description is presented of the measuring chains and measurement techniques. Also described is the method of the disposal of the irradiated probes. The method is presented of the evaluation of measured data and the results are discussed of the analysis of these data. The measurements, including measurements during reactor shut-down and the results of the analysis of the measured data proved good viability and stability of the used calorimetres. The method of measuring the thermocouple signals is simple and the in-service evaluation of required data is quick. In order to increase measurement efficiency it would be appropriate to complete the measuring chain and to automate it. Reliability is a affected merely by protecting the thermocouples against mechanical damage during measurement probe handling and on the reactor. (Z.M.). 5 figs., 5 tabs., 5 refs

Current status of LTO licensing programme for Bohunice nuclear power plant

International Nuclear Information System (INIS)

Borak, J.; Kupca, L.

2012-01-01

The objective of long term operation (LTO) licensing programme for Bohunice nuclear power plant is to demonstrate that the relevant structures and components shall perform their functions throughout the entire LTO period during which they shall meet all the relevant safety requirements. All the activities-which should result in utility's request to obtain the licence for LTO-must be performed in line with the relevant legal basis. As of May 2012, the anticipated duration of currently running programme is thirteen months. All relevant documentation, required by the established legal basis, shall be submitted to the licensing authority one year before the Unit 3 design life expiry. (author)

Proceedings of the 14th International Meeting NUSIM 2006. Joint Slovak, Czech and German Seminar on Nuclear Power

International Nuclear Information System (INIS)

2006-01-01

During April 26-28, 2006 was carried out The 14 th Annual Nuclear Safety Information Meeting, NUSIM 2006. Scientific conference deals with problems of reactor safety upgrading, mainly of two blocks of the NPP V-1 Bohunice as well as decommissioning of the NPP A-1 Bohunice. Other problems of the nuclear engineering were discussed. The Conference proceeded in the following sessions: (I) Survey on the Situation of Nuclear Power in the Partner Countries; (II) Experiences with WWER operation. Almost 100 participants from the Slovak Republic, Austria, Serbia and Montenegro, Czech Republic and Germany took part in the conference. Thirty-three scientific lectures and three papers were presented.

Nuclear safety in Slovak Republic. Status of safety improvements

International Nuclear Information System (INIS)

Toth, A.

1999-01-01

Status of the safety improvements at Bohunice V-1 units concerning WWER-440/V-230 design upgrading were as follows: supplementing of steam generator super-emergency feed water system; higher capacity of emergency core cooling system; supplementing of automatic links between primary and secondary circuit systems; higher level of secondary system automation. The goal of the modernization program for Bohunice V-1 units WWER-440/V-230 was to increase nuclear safety to the level of the proposals and IAEA recommendations and to reach probability goals of the reactor concerning active zone damage, leak of radioactive materials, failures of safety systems and damage shields. Upgrading program for Mochovce NPP - WWER-440/V-213 is concerned with improving the integrity of the reactor pressure vessel, steam generators 'leak before break' methods applied for the NPP, instrumentation and control of safety systems, diagnostic systems, replacement of in-core monitoring system, emergency analyses, pressurizers safety relief valves, hydrogen removal system, seismic evaluations, non-destructive testing, fire protection. Implementation of quality assurance has a special role in improvement of operational safety activities as well as safety management and safety culture, radiation protection, decommissioning and waste management and training. The Year 2000 problem is mentioned as well

Assessment of spent WWER-440 fuel performance under long-term storage conditions

Energy Technology Data Exchange (ETDEWEB)

Kupca, L [VUJE Inc. (Slovakia)

2012-07-01

In the Slovak Republic are under operation 6 units (4 in the Jaslovske Bohunice site, and 2 in the Mochovce), 2 units are under construction in Mochovce site. All units are WWER-440 type. The fresh fuel is imported from the Russian Federation. The spent fuel assemblies are stored in wet conditions in Bohunice Interim Storage Spent Fuel Facility (SFIS). By 15 July 2008, there were 8413 assemblies in SFIS. The objectives are: 1) Wet AR storage of spent fuel from the NPP Bohunice and Mochovce: Surveillance of conditions for spent fuel storage in the at-reactor (AR) storage pools of both NPP's (characteristics of pool water, corrosion product data); Visual control of storage pool components; Evaluation of storage conditions with respect to long-term stability (corrosion of fuel cladding, structural materials); 2) Wet SFIS storage at Bohunice: Measurement of spent fuel conditions during the long-term wet storage, activity data in the storage casks and amount of crud; Surveillance program for SFIS structural materials.

Nuclear energetics as environmentally affable source - present and and future

International Nuclear Information System (INIS)

Suchomel, J.

2002-01-01

In this paper the situation in nuclear energetics in the world in 2000 year is presented. Climatic changes initiated by burning of the fossil fuels an influence of nuclear energetics are discussed. Author informs that European Union and U.S.A. supports developing of nuclear energetics. Nuclear phobia from radiation risk of some inhabitants is compared with risks of other man activities. Possibilities of the electricity production by alternative sources are compared. Liability of the Slovak Republic for decommissioning of two reactor of the V-1 Jaslovske Bohunice NPP in 2006 and 2008, which is compared with the Program of safety improvement of these reactors are discussed. Author and Slovak Nuclear Society accept gladly the suggestion of government of the Slovak Republic that they reassess this liability. The best alternative for decommissioned Jaslovske Bohunice NPP will be the completion of the 3 rd and 4 th blocks of the Mochovce NPP

Contributions of Modranska potrubni a.s. to the safety improvement of piping systems and valves of NPS type VVER 440 and VVER 1000

International Nuclear Information System (INIS)

Slach, J.

2004-01-01

The following activities are described: (i) Installation of pipe whip restraints on piping for high pressure and temperature steam and feed piping; (ii) Installation of air receivers for quick-acting valves with air actuator on VVER 440 units at the Jaslovske Bohunice V2 NPP; (iii) Replacement of the technical water distribution system material in the reactor hall of the Temelin VVER 1000 units; Installation of measuring nozzles on main steam piping DN 600 at the Temelin VVER 1000 units. (P.A.)

Computation code TEP 1 for automated evaluation of technical and economic parameters of operation of WWER-440 nuclear power plant units

International Nuclear Information System (INIS)

Zadrazil, J.; Cvan, M.; Strimelsky, V.

1987-01-01

The TEP 1 program is used for automated evaluation of the technical and economic parameters of nuclear power plant units with WWER-440 reactors. This is an application program developed by the Research Institute for Nuclear Power Plants in Jaslovske Bohunice for the KOMPLEX-URAN 2M information system, delivered by the USSR to the V-2 nuclear power plants in Jaslovske Bohunice and in Dukovany. The TEP 1 program is written in FORTRAN IV and its operation has two parts. First the evaluation of technical and economic parameters of operation for a calculation interval of 10 mins and second, the control of the calculation procedure, follow-up on input data, determination of technical and economic parameters for a lengthy time interval, and data printout and storage. The TEP 1 program was tested at the first unit of the V-2 power plant and no serious faults appeared in the process of the evaluation of technical and economic parameters. A modification of the TEP 1 programme for the Dukovany nuclear power plant is now being tested on the first unit of the plant. (Z.M.)

Comparison of the Safety Critical Software V and V Requirements for the Research Reactor Instrumentation and Control System

Energy Technology Data Exchange (ETDEWEB)

Joo, Sungmoon; Suh, Yong-Suk; Park, Cheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

This study was motivated by a research reactor project where the owner of the project and the equipment vendors are from two different standards frameworks. This paper reviews two major standards frameworks - NRC-IEEE and IAEA-IEC - and the software classification schemes as a background, then discuss the V and V issue. The purpose of this paper is by no means to solve the cross-standards-framework qualification issue, but, rather, is to remind the stakeholders of research reactor projects. V and V are also essential for the approval from regulatory bodies. As standards define or recommend consolidated engineering practices, methods, or criteria, V and V activities for software qualification are not exceptional. Within a standards framework, usually, the processes for the qualification of safety-critical software are well-established such that the safety is maximized while minimizing the compromises in software quality, safety, and reliability. When, however, multiple standards frameworks are involved in a research reactor project, it is difficult for equipment vendors to implement appropriate V and V activities as there is no unified view on this cross-standards-framework qualification issue yet. There are two major standards frameworks for safety-critical software development in nuclear industry. Unfortunately different safety classifications for software and thus different requirements for qualification are in place. What makes things worse is that (i) there are ambiguities in the standards and rooms for each stakeholders’ interpretation, and (ii) there is no one-to-one mapping between the associated V and V methods and activities. These may put the stakeholders of research reactor projects in trouble.

Comparison of the Safety Critical Software V and V Requirements for the Research Reactor Instrumentation and Control System

International Nuclear Information System (INIS)

Joo, Sungmoon; Suh, Yong-Suk; Park, Cheol

2016-01-01

This study was motivated by a research reactor project where the owner of the project and the equipment vendors are from two different standards frameworks. This paper reviews two major standards frameworks - NRC-IEEE and IAEA-IEC - and the software classification schemes as a background, then discuss the V and V issue. The purpose of this paper is by no means to solve the cross-standards-framework qualification issue, but, rather, is to remind the stakeholders of research reactor projects. V and V are also essential for the approval from regulatory bodies. As standards define or recommend consolidated engineering practices, methods, or criteria, V and V activities for software qualification are not exceptional. Within a standards framework, usually, the processes for the qualification of safety-critical software are well-established such that the safety is maximized while minimizing the compromises in software quality, safety, and reliability. When, however, multiple standards frameworks are involved in a research reactor project, it is difficult for equipment vendors to implement appropriate V and V activities as there is no unified view on this cross-standards-framework qualification issue yet. There are two major standards frameworks for safety-critical software development in nuclear industry. Unfortunately different safety classifications for software and thus different requirements for qualification are in place. What makes things worse is that (i) there are ambiguities in the standards and rooms for each stakeholders’ interpretation, and (ii) there is no one-to-one mapping between the associated V and V methods and activities. These may put the stakeholders of research reactor projects in trouble

Physics of Fast and Intermediate Reactors. V. I. Proceedings of the Seminar on the Physics of Fast and Intermediate Reactors. V. I

Energy Technology Data Exchange (ETDEWEB)

NONE

1962-03-15

in all cases that of heir presentation during the Seminar. Changes have been made where it was considered that these would enhance the usefulness of these volumes as reference books. The subject grouping adopted is given below. Volume I - I. Neutron Physics: I.1. Data requirements, I.2. Cross-section measurements, I.3. Fission properties, I.4. Nuclear theory, I.5. Multi-group cross-sections; II. Integral Experiments: II.1. Critical experiments, II.2. Other integral experiments, II.3. Theoretical correlations; Volume II - III. Reactor Theory: III.1. Calculation methods, III.2. Effects of cross-section errors, III.3. Reactivity effects, III.4. Long-term effects, III.5. Reactor concept studies; Volume III - IV. Reactor Dynamics: IV.1. Kinetics, IV.2. Stability, IV.3. Doppler effect, IV.4. Safety problems; V. Physics of Specific Reactors.

Chapter 9. Personnel qualification and training

International Nuclear Information System (INIS)

2000-01-01

In 1999 the Nuclear Regulatory Authority of the Slovak Republic (UJD) focused on the overall training system and on developing programmes for individual categories for NPP V-1 Bohunice, NPP V-2 Bohunice, NPP Mochovce and SE-VYZ. The fundamental theoretical and periodical training for both Bohunice and Mochovce NPPs personnel, simulator training for NPP Bohunice, and periodical simulator training for Bohunice personnel is carried out by the VUJE Training center in Trnava, whereas the simulator training and periodical training for NPP Mochovce is carried at Mochovce plant. Based on a successful passing of examination before the examining committee, UJD issues, a certificate on special professional skills of selected staff of nuclear installations for specific activity for the given type of nuclear installation and for the following positions: (a)Shift manager for scientific start up with the right of manipulation; (b) Shift supervisor; (c) Unit supervisor; (d) Primary circuit operator; (e) Secondary circuit operator; (f) Reactor physicist; (g) Shift manager for scientific start up without the right of manipulation. Examination of selected personnel is described. Last year the examining committee held twelve session for oral theoretical examination. The number of licenses issued in 1999 and the total number of valid licenses is given.Conclusions from inspections carried out by UJD and inspections and tests carried out by the NPP operators in 1999, as well as results from operation and start up of nuclear units confirm that the standard of professional skills of the staff at nuclear installations a high standard of operational safety is being achieved on a permanent basis. Increasing the qualification of UJD staff was done in a form of training and courses scheduled in the plan of training for the staff for 1999. These training, composed of specialized qualification study, functional study, as well as study aimed at maintaining qualification. Training courses organized

Monitoring of Persons at the Exit from Bohunice NPP

International Nuclear Information System (INIS)

Kaizer, J.; Svitek, J.

2001-01-01

Full text: IAEA defines the principal requirement 'defence in depth' as a multilayer system in its authorised document - International Basic Safety Standards for Protection against Ionising Radiation, Safety Series No. 115. The principle of the multilayer system is: a failure at one zone is compensated or corrected at subsequent zones. The main argument why Bohunice NPP modernised its monitoring system at the exit from NPP was the implementation of the principle 'defence in depth'. Several instruments PM7 (Eberline) equipped with the plastic scintillation detectors had been bought because of the modernisation. The instruments had to be integrated into overall security system NPP without any restriction to the number of passing people. The supplier had to modify the basic instrument operation. NPP required a 'dynamic' monitoring version, this means the operation without stopping of a person within the instrument. After the modification the value of the RDA (Reliable Detectable Activity) of the instruments PM7 was within the interval 9.25-10.4 kBq for 137 Cs (dotted source in the middle of the instrument). RDA for the mix of activation products was 2-3 times lower. In conclusion of our paper the results of the monitoring are presented within tree years as well as a discussion about these results. Maximum values of contaminations measured were very low (several kBq) that represented very low risk from potential exposure. (author)

Production of 48V in a nuclear reactor via secondary tritons

International Nuclear Information System (INIS)

Siri, S.; Cohen, I.M.

2009-01-01

The production of 48 V in a nuclear reactor, induced on titanium by tritons generated from the 6 Li(n, t) 4 He reaction, and eventually 7 Li(n, n't) 4 He, is described. Samples of lithium titanate were irradiated for an irradiation cycle (120 h) in the RA-3 reactor, belonging to Ezeiza Atomic Centre. After a radiochemical separation, the characteristic radiations from 48 V were identified in the gamma ray spectra of the vanadium fractions. (orig.)

Experience with quality of training of personnel in start-up, operation and maintenance of nuclear power plants

International Nuclear Information System (INIS)

Ziman, V.; Alaxin, E.

1983-01-01

The theoretical education of personnel takes place in the branch training centre in Jaslovske Bohunice and in the concern training centre of the Slovak Power Plants. Practical training takes place in the Bohunice V-1 power plant. Selected specialists are trained in the training centre of the Novo Voronezh nuclear power plant, at the Paks nuclear plant and in the training centre of the Tusimice power plant. The recruitment, selection, schooling, practical training and placement of personnel and their assignment to posts is done in such a manner as to make sure that the complexly trained personnel is available 6 months to 3 years prior to the physical start-up of the nuclear power plant. The training of university graduates for the post of reactor operator takes 18 months or more. Trained personnel attend in-service training courses in form of complementary courses whose content includes such problems as the elimination of typified possible accidents, on the basis of the analysis of all failures which occurred in the previous period. The rising quality of personnel training at the Bohunice V-1 nuclear power plant is reflected in the decreasing number of failures caused by the human factor and in the increased availability of the power units. (M.D.)

Calibration of a dePangher long counter from 2 keV to 19 MeV

Energy Technology Data Exchange (ETDEWEB)

Slaughter, D R; Rueppel, D W [California Univ., Livermore (USA). Lawrence Livermore Lab.

1977-09-01

The authors have measured the sensitivity of a dePangher precision long counter (PLC) relative to /sup 7/Li(p,n), T(p,n), and T(d,n) differential cross sections over the neutron energy range 10 keV-19 MeV. Absolute sensitivity at 2 keV is also measured, using a scandium filtered beam at a reactor. Results obtained with errors in the range 5-30% are consistent with the assumption of a nearly constant sensitivity over the range 2 keV-6 MeV, but exhibit a reduction above 12 MeV.

Chemistry monitoring and diagnostic system at NPP Jaslovske Bohunice

International Nuclear Information System (INIS)

Smiesko, Ivan; Figedy, Stefan

2012-09-01

This paper provides a description of water chemistry monitoring and diagnostic system installed at Slovak NPP Jaslovske Bohunice. System has complex architecture and covers laboratory data, chemistry and radiochemistry on-line monitoring data, process data acquisition and processing and diagnostics. Pre-filtered data from process computer and chemistry on-line monitors are recorded together with laboratory data in the ORACLE-based information system CHEMIS with many presentation and processing features. Brief information is given about the basic features of a newly developed diagnostic system for early detection and identification of anomalies incoming in the water chemistry regime of the primary and secondary circuit of VVER-440 type unit. This system, called SACHER (System of Analysis of Chemical Regime) has been installed within the major modernization project at the NPP Bohunice in the Slovak Republic. System SACHER has been developed fully in MATLAB environment. Diagnostic system works exclusively with available on-line data as an operation personnel support application allowing effective response to adverse chemistry events/trends. The availability of prompt information about the chemical conditions of the primary and secondary circuit is very important in order to prevent the undue corrosion and deposit build-up processes within the plant systems. The typical chemical information systems that exist and work at the NPPs give the user values of the measured quantities together with their time trends and other derived values. It is then the experienced user's role to recognize the situation the monitored process is in and make the subsequent decisions and take the measures. The SACHER system, based on the computational intelligence techniques, inserts the elements of intelligence into the overall chemical information system. It has the modular structure with the following most important modules: - normality module- its aim is to recognize that the process

Nuclear installations in Slovakia accords to the convention definition

International Nuclear Information System (INIS)

1998-01-01

In this part the nuclear power plants Bohunice - Units V-1 and V-2 and NPP Mochovce (description of units, safety reports and safety improvement programs) are described. Description of Bohunice A-1, history and current status of the NPP A-1 and NPP decommissioning program are included. In next parts interim spent fuel storage, technologies of Raw processing and treatment, and treated and solid Raw storage sites are described

Fast-reactor-data testing of ENDF/B-V at ORNL

International Nuclear Information System (INIS)

Wright, R.Q.; Ford, W.E. III; Lucius, J.L.; Webster, C.C.; Marable, J.H.

1982-01-01

The Cross Section Evaluation Working Group (CSEWG) is coordinating a program to assess the adequacy of ENDF/B-V cross sections for both fast- and thermal-reactor design applications. A secondary goal is to evaluate cross-section processing codes, cross-section libraries, and radiation-transport codes. Fast reactor data testing (FRDT) goals are accomplished, in part, by comparison of calculated results with documented performance parameters of CSEWG fast reactor benchmarks and with results obtained by other data testers. The purpose of this paper is to describe the results of FRDT at Oak Ridge National Laboratory

Existing and near future practices of spent fuel storage in Slovak Republic

International Nuclear Information System (INIS)

Mizov, J.

1999-01-01

In this paper existing and near future practices of spent fuel storage in Slovak Republic are discussed: (1) Reactor operation and spent fuel production; (2) Past policy in spent fuel storage; (3) Away-from-reactor (AFR) storage facility at Bohunice NPP site; (4) Present policy in spent fuel storage; (5) Final disposal of spent fuel

Fast breeder reactors: Experience and trends. V. 2

International Nuclear Information System (INIS)

1986-01-01

The IAEA Symposium on ''Fast Breeder Reactors: Experience and Future Trends'' was held, at the invitation of the Government of France, in Lyons, France, on 22-26 July 1985. It was hosted by the French Commissariat a l'energie atomique and Electricite de France. The purpose of the Symposium was to review the experience gained so far in the field of LMFBRs, taking into account the constructional, operational, technological, economic and fuel cycle aspects, and to consider the developmental trends as well as the international co-operation in fast breeder reactor design and utilization. The Symposium was attended by almost 400 participants (340 participants, 35 observers and 20 journalists) from 25 countries and five international organizations. More than 80 papers were presented and discussed during six regular sessions and four poster sessions. A separate abstract was prepared for each of these papers

Adoption of in-vessel retention concept for VVER-440/V213 reactors in Central European Countries

Energy Technology Data Exchange (ETDEWEB)

Matejovic, Peter, E-mail: peter.matejovic@ivstt.sk [Inzinierska Vypoctova Spolocnost (IVS), Jana Holleho 5, 91701 Trnava (Slovakia); Barnak, Miroslav; Bachraty, Milan; Vranka, Lubomir [Inzinierska Vypoctova Spolocnost (IVS), Jana Holleho 5, 91701 Trnava (Slovakia); Berky, Robert [Integrita a Bezpecnost Ocelovych Konstrukcii, Rybnicna 40, 831 07 Bratislava (Slovakia)

2017-04-01

Highlights: • Design of in-vessel retention concept for VVER-440/V213 reactors. • Thermal loads acting on the inner reactor surface. • Structural response of reactor pressure vessel. • External reactor vessel cooling. - Abstract: An in-vessel retention (IVR) concept was proposed for standard VVER-440/V213 reactors equipped with confinement made of reinforced concrete and bubbler condenser pressure suppression system. This IVR concept is based on simple modifications of existing plant technology and thus it was attractive for plant operators in Central European Countries. Contrary to the solution that was adopted before at Loviisa NPP in Finland (two units of VVER-440/V213 reactor with steel confinement equipped with ice condenser), the coolant access to the reactor pressure vessel from flooded cavity is enabled via closable hole installed in the centre of thermal shield of the reactor lower head instead of lowering this massive structure in the case of severe accident. As a consequence, the crucial point of this IVR concept is narrow gap between torispherical lower head and thermal and biological shield. Here the highest thermal flux is expected in the case of severe accident. Thus, realistic estimation of thermal load and corresponding deformations of reactor wall and their impact on gap width for coolant flow are of primarily importance. In this contribution the attention is paid especially to the analytical support with emphasis to the following points: 1) {sup ∗}Estimation of thermal loads acting on the inner reactor surface; 2) {sup ∗}Estimation of structural response of reactor pressure vessel (RPV) with emphasis on the deformation of outer reactor surface and its impact on the annular gap between RPV wall and thermal/biological shield; 3) {sup ∗}Analysis of external reactor vessel cooling. For this purpose the ASTEC code was used for performing analysis of core degradation scenarios, the ANSYS code for structural analysis of reactor vessel

Search for eV sterile neutrinos at a nuclear reactor — the Stereo project

Science.gov (United States)

Haser, J.; Stereo Collaboration

2016-05-01

The re-analyses of the reference spectra of reactor antineutrinos together with a revised neutrino interaction cross section enlarged the absolute normalization of the predicted neutrino flux. The tension between previous reactor measurements and the new prediction is significant at 2.7 σ and is known as “reactor antineutrino anomaly”. In combination with other anomalies encountered in neutrino oscillation measurements, this observation revived speculations about the existence of a sterile neutrino in the eV mass range. Mixing of this light sterile neutrino with the active flavours would lead to a modification of the detected antineutrino flux. An oscillation pattern in energy and space could be resolved by a detector at a distance of few meters from a reactor core: the neutrino detector of the Stereo project will be located at about 10 m distance from the ILL research reactor in Grenoble, France. Lengthwise separated in six target cells filled with 2 m3 Gd-loaded liquid scintillator in total, the experiment will search for a position-dependent distortion in the energy spectrum.

Thermal reactor benchmark tests on JENDL-2

International Nuclear Information System (INIS)

Takano, Hideki; Tsuchihashi, Keichiro; Yamane, Tsuyoshi; Akino, Fujiyoshi; Ishiguro, Yukio; Ido, Masaru.

1983-11-01

A group constant library for the thermal reactor standard nuclear design code system SRAC was produced by using the evaluated nuclear data JENDL-2. Furthermore, the group constants for 235 U were calculated also from ENDF/B-V. Thermal reactor benchmark calculations were performed using the produced group constant library. The selected benchmark cores are two water-moderated lattices (TRX-1 and 2), two heavy water-moderated cores (DCA and ETA-1), two graphite-moderated cores (SHE-8 and 13) and eight critical experiments for critical safety. The effective multiplication factors and lattice cell parameters were calculated and compared with the experimental values. The results are summarized as follows. (1) Effective multiplication factors: The results by JENDL-2 are considerably improved in comparison with ones by ENDF/B-IV. The best agreement is obtained by using JENDL-2 and ENDF/B-V (only 235 U) data. (2) Lattice cell parameters: For the rho 28 (the ratio of epithermal to thermal 238 U captures) and C* (the ratio of 238 U captures to 235 U fissions), the values calculated by JENDL-2 are in good agreement with the experimental values. The rho 28 (the ratio of 238 U to 235 U fissions) are overestimated as found also for the fast reactor benchmarks. The rho 02 (the ratio of epithermal to thermal 232 Th captures) calculated by JENDL-2 or ENDF/B-IV are considerably underestimated. The functions of the SRAC system have been continued to be extended according to the needs of its users. A brief description will be given, in Appendix B, to the extended parts of the SRAC system together with the input specification. (author)

Production of {sup 48}V in a nuclear reactor via secondary tritons

Energy Technology Data Exchange (ETDEWEB)

Siri, S. [Comision Nacional de Energia Atomica, Centro Atomico Ezeiza, Gerencia de Capacitacion, Quimica Nuclear y Ciencias de la Salud, Ezeiza, Buenos Aires (Argentina); Cohen, I.M. [Univ. Tecnologica Nacional, Dept. de Ingenieria Quimica, Buenos Aires (Argentina)

2009-07-01

The production of {sup 48}V in a nuclear reactor, induced on titanium by tritons generated from the {sup 6}Li(n, t){sup 4} He reaction, and eventually {sup 7}Li(n, n't){sup 4}He, is described. Samples of lithium titanate were irradiated for an irradiation cycle (120 h) in the RA-3 reactor, belonging to Ezeiza Atomic Centre. After a radiochemical separation, the characteristic radiations from {sup 48}V were identified in the gamma ray spectra of the vanadium fractions. (orig.)

Reactor BR2

Energy Technology Data Exchange (ETDEWEB)

Gubel, P

2000-07-01

The BR2 reactor is still SCK-CEN's most important nuclear facility. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. Various aspects concerning the operation of the BR2 Reactor, the utilisation of the CALLISTO loop and the irradiation programme, the BR2 R and D programme and the production of isotopes and of NTD-silicon are discussed. Progress and achievements in 1999 are reported.

Reactor BR2

International Nuclear Information System (INIS)

Gubel, P.

2000-01-01

The BR2 reactor is still SCK-CEN's most important nuclear facility. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. Various aspects concerning the operation of the BR2 Reactor, the utilisation of the CALLISTO loop and the irradiation programme, the BR2 R and D programme and the production of isotopes and of NTD-silicon are discussed. Progress and achievements in 1999 are reported

Testing ENDF/B-V data for thermal reactors

International Nuclear Information System (INIS)

Craig, D.S.

1982-10-01

Lattice parameters have been calculated for some thermal reactor benchmark lattices using ENDF/B-V data. These lattices were TRX-1, -2; BAPL-UO 2 -1,-2,-3; BNL-ThO 2 - 233 UO 2 -H 2 0-1,-2,-3; MIT-4,-5,-6; and PNL-31,-33,-35 (infinite lattices). In addition, parameters were calculated for 3 ZEEP lattices, 3 High-Conversion U0 2 -H 2 0 lattices, and 7 BNL-Th0 2 - 233 U0 2 -D 2 0 lattices. These calculations were made using the integral transport cell code RAHAB with the resonance reaction rates obtained using the OZMA code operating in the discrete ordinate mode. This code calculates the resonance rates allowing for the interaction of all resonances. Four group reaction rates for use in method comparisons are given for several lattices. The author discusses the use of the OZMA code for these calculations, including the choice of options and the orders of the angular quadratures, and compares results obtained using the CRNL thermal scattering data with those obtained using ENDF/B data

Status of data testing of ENDF/B-V reactor dosimetry file

International Nuclear Information System (INIS)

Magurno, B.A.

1979-01-01

The ENDF/B-V Reactor Dosimetry File was released August 1979, and Phase II data testing started. The results presented here are from Brookhaven National Laboratory only, and are considered preliminary. The tests include calculated spectrum-averaged cross sections using 235 U fission spectrum (Watt), 252 Cf spontaneous fission spectrum (Watt and Maxwellian), and the Coupled Fast Reactor Measurement Facility (CFRMF) spectrum. 6 tables

Evaluation of an external exposure of a worker during manipulation with waste packages stored in Bohunice radioactive waste treatment centre

International Nuclear Information System (INIS)

Slimak, A.; Hrncir, T.; Necas, V.

2012-01-01

The paper briefly describes current state of radioactive waste management as well as radioactive waste treatment and conditioning technologies used in Bohunice Radioactive Waste Treatment Centre. Radioactive Waste management includes pretreatment, treatment, conditioning, storage, transport and disposal of radioactive waste. Presented paper deals with the evaluation of an external exposure of a worker during manipulation with fibre-reinforced concrete container stored under shelter object. The external exposure of a worker was evaluated using VISIPLAN 3D ALARA code. (Authors)

V.S.O.P.-computer code system for reactor physics and fuel cycle simulation

International Nuclear Information System (INIS)

Teuchert, E.; Hansen, U.; Haas, K.A.

1980-03-01

V.S.O.P. (Very Superior Old Programs) is a system of codes linked together for the simulation of reactor life histories. It comprises neutron cross section libraries and processing routines, repeated neutron spectrum evaluation, 2-D diffusion calculation based on neutron flux synthesis with depletion and shutdown features, incore and out-of-pile fuel management, fuel cycle cost analysis, and thermal hydraulics (at present restricted to Pebble Bed HTRs). Various techniques have been employed to accelerate the iterative processes and to optimize the internal data transfer. A limitation of the storage requirement to 360 K-bites is achieved by an overlay structure. The code system has been used extensively for comparison studies of reactors, their fuel cycles, and related detailed features. Beside its use in research and development work for the high temperature reactor the system has been applied successfully to LWR and Heavy Water Reactors. (orig.) [de

High energy resolution characteristics on 14MeV neutron spectrometer for fusion experimental reactor

Energy Technology Data Exchange (ETDEWEB)

Iguchi, Tetsuo [Tokyo Univ., Tokai, Ibaraki (Japan). Nuclear Engineering Research Lab.; Takada, Eiji; Nakazawa, Masaharu

1996-10-01

A 14MeV neutron spectrometer suitable for an ITER-like fusion experimental reactor is now under development on the basis of a recoil proton counter telescope principle in oblique scattering geometry. To verify its high energy resolution characteristics, preliminary experiments are made for a prototypical detector system. The comparison results show reasonably good agreement and demonstrate the possibility of energy resolution of 2.5% in full width at half maximum for 14MeV neutron spectrometry. (author)

Radioactive waste management at WWER type reactors

International Nuclear Information System (INIS)

1993-05-01

This report was prepared within the framework of the Technical Assistance Regional Project on Advice on Waste Management at WWER Type Reactors, which was initiated by the IAEA in 1991. The Regional Project is an integral part of the IAEA's activities directed towards improvement of the safety and reliability of nuclear power plants with WWER type reactors (Soviet designed PWRs). Forty-five WWER type units are currently in operation and twenty-five are under construction in Bulgaria, Czechoslovakia, Finland, Hungary and the former USSR. The idea of regional collaboration between eastern European countries under the auspices of the IAEA was discussed for the first time during the last meeting of the Council for Mutual Economic Assistance (CMEA) on spent fuel and radioactive waste management, held in Rez, Czechoslovakia, in October 1990. Since then, the CMEA and some of its former Member States have ceased to exist. However, there are many reasons for eastern European countries to continue their regional collaboration at a higher level. The USSR, the designer and supplier of WWER type reactors in eastern European countries, participated in the first phase of the project. The majority of WWER type reactors are situated in States of the former USSR (Russia and Ukraine). The main results of the first phase of the Regional Project are: (i) Re-establishment of communication channels among eastern European countries operating WWER type reactors by incorporating the IAEA's technical assistance; (ii) Identification of common waste management problems (administrative and technical) requiring resolution; (iii) Familiarization with radioactive waste management systems at nuclear power plants with WWER type reactors - Paks (Hungary), Loviisa (Finland), Jaslovske Bohunice (Czechoslovakia) and Novovoronezh (Russian Federation). Tabs

Independent CO2 loop for cooling the samples irradiated in the RA reactor vertical experimental channels, Task 2.50.05

International Nuclear Information System (INIS)

Stojic, M.; Pavicevic, M.

1964-01-01

This report contains the following volumes V and VI of the Project 'Independent CO 2 loop for cooling the samples irradiated in RA reactor vertical experimental channels': Design project of the dosimetry control system in the independent CO 2 loop for cooling the samples irradiated in the RA reactor vertical experimental channels, and Safety report for the Independent CO 2 loop for cooling the samples irradiated in the RA reactor vertical experimental channels [sr

Design and testing of reactors for 735 kV

Energy Technology Data Exchange (ETDEWEB)

Erb, W; Kraaij, D J

1965-11-01

The design and testing of five large, single phase shunt reactors rated either 110 or 55 MVAR, supplied for the 735 kV system of the Quebec Hydro Electric Commission which came into operation in the autumn of 1965 are described. As these reactors are permanently connected to the transmission lines, their losses must be considered as being continuously present and must be determined exactly. In addition to the use of a new bridge method, the losses were also measured calorimetrically for the purpose of comparison, the agreement between the two tests being remarkably good. The impulse tests with full wave and chopped wave are subsequently described.

Research reactor core conversion guidebook. V.2: Analysis (Appendices A-F)

International Nuclear Information System (INIS)

1992-04-01

Volume 2 consists of detailed Appendices, covering safety analyses for generic 10 MW reactor, safety analysis - probabilistic methods, methods for preventing LOCA, radiological consequence analyses, examples of safety report amendments and safety specifications. Included in Volume 2 are example analyses for cores with with highly enriched uranium and low enriched uranium fuels showing differences that can be expected in the safety parameters and radiological consequences of postulated accidents. There are seven examples of licensing documents related to core conversion and two examples of methods for determining power limits for safety specifications in the document. Refs, figs, bibliographies and tabs

VUEZ. Annual report 2004

International Nuclear Information System (INIS)

2005-01-01

A brief account of activities carried out by the Vyskumny ustav energetickych zariadeni, a.s. (VUEZ) in 2004 is presented. These activities are reported under the headings: (1) Introductory address by the Chairman of the Board of Directors; (2) Mission and vision; (3) Basic data; (4) Product portfolio and customer services; (5) VUEZ - Quality policy; (6) Human resources; (7) Economic data; (8) Auditor's certificate; (8) Adving, s.r.o.; (9) Contact persons and addresses. In 2004, the decisive domestic market capacities of VUEZ were focused on its main business partner SE, a.s., particularly on the Jaslovske Bohunice NPP. VUEZ was one of the major contractors participating in investment projects such as the Upgrading of the Jaslovske Bohunice V2 NPP. In addition, sealing work and periodical integrated leakage rate tests in nuclear power plants were resumed. In the field of fossil-fuel power plants, a substantial increase in services provided by VUEZ Emission Measurement Laboratory was recorded. In the field of experimental research, another bilateral project was implemented with IRSN Paris - an extensive programme aimed at verifying the operational reliability of emergency core cooling systems for PWR reactors. In 2004, experimental tests in this field were performed also for Westinghouse. In the process of preparation for the Jaslovske Bohunice V1 NPP decommissioning, intensive work was performed for the Project Management Unit Consultant - an international consortium consisting of Electricite de France, Empresarios Agrupados Internacional S.A., Iberdrola Ingenieria y Consultoria S.A., and Soluziona Ingenieria S.A. In the field of leak-tightness improvement in nuclear power plants, work was executed in foreign plants such as the Dukovany NPP, Czech Republic, and the Paks NPP, Hungary. In the field of investment deliveries, hermetic doors designed for the RAW Repository in the Paks NPP were manufactured for and delivered to OLAJTERV R.t. Company, Budapest, Hungary

Tensile properties and microstructure of helium-injected and reactor-irradiated V-20 Ti

International Nuclear Information System (INIS)

Tanaka, M.P.; Bloom, E.E.; Horak, J.A.

1981-01-01

Mechanical properties and microstructure of vanadium-20% titanium were examined following helium-injection and reactor irradiation. Helium was injected at ambient temperature to concentrations of 90 and 200 at. ppM; neutron irradiation was at 400, 575, 625, and 700 0 C to fluence of 3 x 10 26 n/m 2 , E > 0.1 MeV. Cavities representing negligible volume swelling were observed in all helium-injected specimens. Degradation of mechanical properties, especially loss of ductility due to helium, occurred at temperatures of 625 and 700 0 C. The levels of helium produced in the fusion spectrum can be expected to alter the response of vanadium alloys from that observed in fast reactor irradiations

Tensile properties and microstructure of helium-injected and reactor-irradiated V-20 Ti

Energy Technology Data Exchange (ETDEWEB)

Tanaka, M.P.; Bloom, E.E.; Horak, J.A.

1981-01-01

Mechanical properties and microstructure of vanadium-20% titanium were examined following helium-injection and reactor irradiation. Helium was injected at ambient temperature to concentrations of 90 and 200 at. ppM; neutron irradiation was at 400, 575, 625, and 700/sup 0/C to fluence of 3 x 10/sup 26/ n/m/sup 2/, E > 0.1 MeV. Cavities representing negligible volume swelling were observed in all helium-injected specimens. Degradation of mechanical properties, especially loss of ductility due to helium, occurred at temperatures of 625 and 700/sup 0/C. The levels of helium produced in the fusion spectrum can be expected to alter the response of vanadium alloys from that observed in fast reactor irradiations.

Safety of reactors built according to earlier standards (WWER 440/V230 type)

International Nuclear Information System (INIS)

Misak, J.; Rohar, S.

1995-01-01

The problems of safety of WWER-440/V-230 type reactors are discussed, and the following conclusions are made. (1) The reactors have a very good operational record. (2) The reactors have serious design shortcomings, which should be eliminated by safety upgrading. Core damage frequency should be further reduced. (3) PSA methods constitute an appropriate tool for assessment of plant vulnerability to some initiating events and malfunctions, for prioritization of upgrading measures and for tolerability of deviations from current safety standards. (4) The most important safety merits, such as a large thermal inertia and low rupture probability, should be properly taken into account in the analysis. (5) Extensive safety upgrading is feasible and can lead to a considerable risk reduction. In certain circumstances such upgrading is the least expensive option even though the total cost is much higher than the initial plant construction cost. (6) Properly upgraded, the reactor units may be operable until better power resources are available within the country. (7) The existing gap between the technological and political judgements of nuclear safety should be reduced continuously by information exchange improvements. (8) A unified approach to nuclear safety should be adopted for all nuclear reactors (not just WWERs) built to earlier standards. 5 tabs., 1 fig

Borate compound content reduction in liquid radioactive waste from nuclear power plants with VVER reactor

International Nuclear Information System (INIS)

Szalo, A.; Zatkulak, M.

2000-01-01

This paper describes the current status of liquid waste (evaporator concentrates) inventory at V-1 and V-2 NPPs in Jaslovske Bohunice and the intention to separate boron from them with respect to waste minimisation and improvement of physical and chemical properties for further waste treatment and conditioning. Preliminary results of laboratory experiments concerned to borate crystallisation after pH adjustment with nitric or formic acid performed in the 1998 are given. At the present time laboratory experiments continuing - next acids, coagulation with carbon oxide, electrolytic process, ion exchange resin, study of decontamination factors, immobilization of boric acid, decrease radioactivity, purification of boron-contained compounds. Slovenske Elektrarne have accumulated 7,000 m 3 of evaporator concentrates containing 100-180 g/l borate. In order to make more storage space available, it is proposed to remove some of the borate in the liquor by precipitation as sodium tetraborate and immobilise in either cement of bitumen. The supernate can be further volume reduced by evaporation and returned to the tanks. Slovenske Elektrarne are currently evaluating acid addition to the pH 12-13 concentrate to reduce the borate solubility. However, this adds to the salt burden of the waste through this chemical addition -thus creating future increases in conditioning and disposal costs. Boric acid is used in pressurized water as a soluble neutron poison to control reactivity and also to assure a safety margin in the spent fuel pool and during refuelling operations. Boric acid is also present in the water reserved for injection into the reactor in the event of postulated accidents. (author)

Evaluation of fatigue crack growth in the primary circuit pipeline of a WWER 440/213c type nuclear power plant

International Nuclear Information System (INIS)

Samohyl, P.

1993-07-01

The fatigue damage of the primary circuit of WWER-440/213c reactors was evaluated proceeding from actual and design operating data of units 3 and 4 of the Bohunice V-2 nuclear power plant. A complex computation model was set up, encompassing the main circulation pipeline, pressurizer pipeline, emergency core aftercooling system pipeline, steam pipeline, and feedwater pipeline. The standardized STATIC code was applied to the stress analysis, and the FATLBB code was used to determine the crack increment for all operating states and primary circuit sections. The probability of fatigue failure of the pipelines was found to be low. (J.B.). 55 tabs., 3 figs., 9 refs

CSRL-V ENDF/B-V 227-group neutron cross-section library and its application to thermal-reactor and criticality safety benchmarks

International Nuclear Information System (INIS)

Ford, W.E. III; Diggs, B.R.; Knight, J.R.; Greene, N.M.; Petrie, L.M.; Webster, C.C.; Westfall, R.M.; Wright, R.Q.; Williams, M.L.

1982-01-01

Characteristics and contents of the CSRL-V (Criticality Safety Reference Library based on ENDF/B-V data) 227-neutron-group AMPX master and pointwise cross-section libraries are described. Results obtained in using CSRL-V to calculate performance parameters of selected thermal reactor and criticality safety benchmarks are discussed

Upgrading of the radiation protection system at the V1 NPP

International Nuclear Information System (INIS)

Dobis, L.; Kaizer, J.; Svitek, J.

2003-01-01

The original radiation protection system at Bohunice V1 NPP from the 1970s was upgraded so as to meet current national as well as international standards. The article describes the upgrading of the radiation control system (teledosimetry, emergency measurement in the hermetic zone, liquid discharges, gaseous discharges, service water, remote measurement, hygiene loop, contamination monitoring at the controlled zone exit and activity monitoring at the NPP exit, special laundry, instrument calibration), dosimetry, software, and personnel contamination inspection/measurement. (author)

Model of nuclear reactor type VVER-1000/V-320 built by computer code ATHLET-CD

International Nuclear Information System (INIS)

Georgiev, Yoto; Filipov, Kalin; Velev, Vladimir

2014-01-01

A model of nuclear reactor type VVER-1000 V-320 developed for computer code ATHLET-CD2.1A is presented. Validation of the has been made, in the analysis of the station blackout scenario with LOCA on fourth cold leg is shown. As the calculation has been completed, the results are checked through comparison with the results from the computer codes ATHLET-2.1A, ASTEC-2.1 and RELAP5mod3.2

Termination of exploitation of V 1 NPP - BIDSF projects

International Nuclear Information System (INIS)

Pnackova, L.

2004-01-01

In this paper the interview with engineer Peter Hlbocky, director of division of the Project of decommissioning of V 1 Nuclear Power Plant in Jaslovske Bohunice is presented. Project Manager Unit (PMU) was formed on the basis of directive of the General Director of the Slovenske elektrarne, a.s. The Director of the Division of decommissioning of the V 1 NPP and at the same time the Main manager of the PMU is engineer Peter Hlbocky. On this project participate 19 employees of the Slovenske elektrarne, a. s. (SE), 6 abroad employees of the consortium IBERINCO, 15 employees of the VUEZ and 25 abroad employees on the detached place of work in the Spain and France

Problems of WWER-440 dynamic changes

International Nuclear Information System (INIS)

Rydzi, S.

1986-01-01

The data processing capability of the DYNAMIKA program is presented and demonstrated for the calculation of coolant parameters and heat transfer variables of the WWER reactor in accident and transient modes of operation. An experimental outage is described of the TG 11 turbogenerator at the V-1 Jaslovske Bohunice nuclear power plant. The measured values were compared with values calculated using the DYNAMIKA program. The graphic representation makes it evident that the mathematical model comes very close to reality. (J.B.)

The PLTEMP V2.1 code

International Nuclear Information System (INIS)

Olson, A.P.

2003-01-01

Recent improvements to the computer code PLTEMP/ANL V2.1 are described. A new iterative, error-minimization solution technique is used to obtain the thermal distribution both within each fuel plate, and along the axial length of each coolant channel. A new, radial geometry solution is available for tube-type fuel assemblies. Software comparisons of these and other new models are described. Applications to Russian-designed IRT-type research reactors are described. (author)

Tensile properties and microstructure of helium injected and reactor irradiated V-20 Ti

International Nuclear Information System (INIS)

Tanaka, M.P.; Bloom, E.E.; Horak, J.A.

1980-01-01

The objective of this work was to determine the effect of preinjected helium followed by neutron irradiation on the mechanical properties and microstructure of V-20% Ti. These results will be used for the evaluation of the potential use of V-20% Ti in fusion reactor service

TiO2-photocatalyzed As(III) oxidation in a fixed-bed, flow-through reactor.

Science.gov (United States)

Ferguson, Megan A; Hering, Janet G

2006-07-01

Compliance with the U.S. drinking water standard for arsenic (As) of 10 microg L(-1) is required in January 2006. This will necessitate implementation of treatment technologies for As removal by thousands of water suppliers. Although a variety of such technologies is available, most require preoxidation of As(III) to As(V) for efficient performance. Previous batch studies with illuminated TiO2 slurries have demonstrated that TiO2-photocatalyzed AS(III) oxidation occurs rapidly. This study examined reaction efficiency in a flow-through, fixed-bed reactor that provides a better model for treatment in practice. Glass beads were coated with mixed P25/sol gel TiO2 and employed in an upflow reactor irradiated from above. The reactor residence time, influent As(III) concentration, number of TiO2 coatings on the beads, solution matrix, and light source were varied to characterize this reaction and determine its feasibility for water treatment. Repeated usage of the same beads in multiple experiments or extended use was found to affect effluent As(V) concentrations but not the steady-state effluent As(III) concentration, which suggests that As(III) oxidation at the TiO2 surface undergoes dynamic sorption equilibration. Catalyst poisoning was not observed either from As(V) or from competitively adsorbing anions, although the higher steady-state effluent As(III) concentrations in synthetic groundwater compared to 5 mM NaNO3 indicated that competitive sorbates in the matrix partially hinder the reaction. A reactive transport model with rate constants proportional to incident light at each bead layer fit the experimental data well despite simplifying assumptions. TiO2-photocatalyzed oxidation of As(III) was also effective under natural sunlight. Limitations to the efficiency of As(III) oxidation in the fixed-bed reactor were attributable to constraints of the reactor geometry, which could be overcome by improved design. The fixed-bed TiO2 reactor offers an environmentally

XRD study of yttria stabilized zirconia irradiated with 7.3 MeV Fe, 10 MeV I, 16 MeV Au, 200 MeV Xe and 2.2 GeV Au ions

Energy Technology Data Exchange (ETDEWEB)

Nakano, K.; Yoshizaki, H. [Department of Materials Science, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan); Saitoh, Y. [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, Takasaki, Gunma 370-1292 (Japan); Ishikawa, N. [Tokai Research and Development Center, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Iwase, A., E-mail: iwase@mtr.osakafu-u.ac.jp [Department of Materials Science, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan)

2016-03-01

To simulate energetic neutron irradiation effects, yttria-stabilized zirconia (YSZ) which is one of the major materials for electrical corrosion potential sensors (ECP sensors) was irradiated with heavy ions at energies ranging from 7.3 MeV to 2.2 GeV. Ion irradiation effects on the lattice structure were analyzed using the X-ray diffraction (XRD). The increase in lattice constant was induced by the ion irradiation. It was dominated by the elastic collision process and not by the electronic excitation process. The lattice disordering which was observed as a broadening of XRD peaks was also induced by the irradiation especially for 200 MeV Xe ion irradiation. The present result suggests that the expansion and/or the disordering of YSZ lattice induced by energetic neutrons may affect the durability of a joint interface between a metal housing and YSZ membrane for the usage of ECP sensors in nuclear power reactors.

RELAP5/MOD3.2 investigation of reactor vessel YR line capabilities for primary side depressurization during the TLFW in VVER1000/V320

International Nuclear Information System (INIS)

Gencheva, Rositsa V.; Stefanova, Antoaneta E.; Groudev, Pavlin P.

2005-01-01

During the development of Symptom Based Emergency Operating Procedures (SB-EOPs) for VVER-1000/V320 units at Kozloduy Nuclear Power Plant (NPP), a number of analyses have been performed using the RELAP5/MOD3.2 computer code. One of them is 'Investigation of reactor vessel YR line capabilities for primary side depressurization during the Total Loss of Feed Water (TLFW)'. The main purpose of these calculations is to evaluate the capabilities of YR line located at the top of the reactor vessel for primary side depressurization to the set point of High Pressure Injection System (HPIS) actuation and the abilities for successful core cooling after Feed and Bleed procedure initiation. For the purpose of this, operator action with 'Reactor vessel off-gas valve - 0.032 m' opening has been investigated. RELAP5/MOD3.2 computer code has been used to simulate the TLFW transient in VVER-1000 NPP model. This model was developed at Institute for Nuclear Research and Nuclear Energy - Bulgarian Academy of Sciences (INRNE-BAS), Sofia, for analyses of operational occurrences, abnormal events, and design basis scenarios. The model provides a significant analytical capability for the specialists working in the field of NPP safety

Chapter No.8. Personnel qualification and training

International Nuclear Information System (INIS)

2002-01-01

The overall training system and the development projects of training the staff of all categories from NPP V-1, NPP V-2 Bohunice, SE-VYZ and NPP Mochovce were the subject of UJD's attention. During 2001 following inspections were carried out on nuclear personnel training: - PP's Bohunice: an inspection focused on compliance with requirements for staff qualifications and compliance with the prescribed training of Bohunice plant staff; - Mochovce NPP: an inspection focused on compliance with the requirements for staff qualifications and compliance with the prescribed training of NPP Mochovce staff; - SE-VYZ: an inspection focused on compliance with the requirements for staff qualifications and compliance with the prescribed training of SE-VYZ staff. Training the staff of the NPP's Bohunice: - The fundamental and periodical theoretical training as sure as the fundamental and periodical simulator training is carried out by the VUJE Training centre in Trnava. - The fundamental practical training in the workplace and training for the change work- rank is carried at Bohunice plant. Training of the staff of the NPP Mochovce: - The fundamental and periodical theoretical training is carried out by the VUJE Training centre in Trnava. The fundamental practical training in the workplace and training for the change work- rank as well as the fundamental and periodical simulator training is carried at Mochovce plant. Based on a successful passing of examination before the examining committee, UJD issues a certificate on special professional skills of selected staff members of nuclear installations for specific activity for the given type of nuclear installation and for the following positions: 1. Scientific shift manager for start up with the right of manipulation; 2. Shift supervisor; 3. Unit supervisor; 4. Primary circuit operator; 5. Secondary circuit operator; 6. Reactor physicist; 7. Scientific shift manager for start up without the right of manipulation. Examinations of

Integral activation experiment of fusion reactor materials with d-Li neutrons up to 55 MeV

Energy Technology Data Exchange (ETDEWEB)

Maekawa, Fujio; Ikeda, Yujiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Moellendorff, Ulrich von [Forschungszentrum Karlsruhe, Karlsruhe (Germany); Wada, Masayuki [Business Automation Co., Ltd., Tokyo (Japan)

2000-03-01

An integral activation experiment of fusion reactor materials with a deuteron-lithium neutron source was performed. Since the maximum energy of neutrons produced was 55 MeV, the experiment with associated analysis was one of the first attempts for extending the energy range beyond 20 MeV. The following keywords represent the present study: d-Li neutrons, 55 MeV, dosimetry, SAND-II, spectrum adjustment, LA-150, MCNP, McDeLi, IFMIF, fusion reactor materials, integral activation experiment, low-activation, F82H, vanadium-alloy, IEAF, ALARA, and sequential charged particle reaction. (author)

Pb(n,2n) cross section at 14.1 MeV

International Nuclear Information System (INIS)

Zhou Delin

1991-01-01

Pb is a potential candidate for the neutron multiplier of the fusion reactor, so its (n, 2n) cross section at 14 MeV is of importance. This work is carried out to get a new evaluation of Pb (n,2n) cross section at 14.1 MeV for checking the angle-integrated neutron emission cross section. The equal weight averaged value 2252 +- 40 Mb is adopted in the evaluation

ANSL-V: ENDF/B-V based multigroup cross-section libraries for Advanced Neutron Source (ANS) reactor studies

International Nuclear Information System (INIS)

Ford, W.E. III; Arwood, J.W.; Greene, N.M.; Petrie, L.M.; Primm, R.T. III; Waddell, M.W.; Webster, C.C.; Westfall, R.M.; Wright, R.Q.

1987-01-01

Multigroup P3 neutron, P0-P3 secondary gamma ray production (SGRP), and P6 gamma ray interaction (GRI) cross section libraries have been generated to support design work on the Advanced Neutron Source (ANS) reactor. The libraries, designated ANSL-V (Advanced Neutron Source Cross-Section Libraries), are data bases in a format suitable for subsequent generation of problem dependent cross sections. The ANSL-V libraries are available on magnetic tape from the Radiation Shielding Information Center at Oak Ridge National Laboratory

Nuclear business worth billions begins

International Nuclear Information System (INIS)

Beer, G.; Marcan, P.; Slovak, K.

2005-01-01

The first V1 unit of Bohunice nuclear power station is to be shutdown by the end of next year. However, its decommissioning can only start in 2011 as before the decommissioning can start the second unit must be shutdown and the nuclear fuel to be stored in a basin must cool down. But in spite of these limitations, the decommissioning process has already started. Various analyses and projects have been put out to tender, work on the technical division of the decommissioned V1 units from the V2 units, which will remain in service, has also began. The state owned company, GovCo, a.s., will be in charge of the decommissioning of the V1 units. The method to be applied to the decommissioning of the V1 units has not yet been selected. The project management unit of Slovak Electric favours immediate decommissioning. 'Not only will decommissioning start immediately following the removal of the nuclear fuel, but it will also be done continuously,'explained unit director, Peter Hlbocky. Using this procedure, decommissioned could be complete by 2026. The question as to whether the power plant will be completely decommissioned to create a green field site will, according to P. Hlbocky, depend on Slovakia's future plans regarding nuclear energy generation at Jaslovske Bohunice, which could be a suitable location for building a new nuclear power station. In such a case, a part of the infrastructure would remain in place. 'Should Slovakia decide to continue its nuclear program, it would be a waste not to take advantage of the existing infrastructure,' said P. Hlbocky. The cabinet is to decide on the method to be used for decommissioning of the V1 reactor and the time frame for the process by the end of next year. The cabinet will decide mainly on the basis of cost estimates to be prepared together with decommissioning concept that is currently under preparation. The decommissioning concept financed by the Bohunice International Decommissioning Support Fund should provide more

CSRL-V: processed ENDF/B-V 227-neutron-group and pointwise cross-section libraries for criticality safety, reactor, and shielding studies

International Nuclear Information System (INIS)

Ford, W.E. III; Diggs, B.R.; Petrie, L.M.; Webster, C.C.; Westfall, R.M.

1982-01-01

A P 3 227-neutron-group cross-section library has been processed for the subsequent generation of problem-dependent fine- or broad-group cross sections for a broad range of applications, including shipping cask calculations, general criticality safety analyses, and reactor core and shielding analyses. The energy group structure covers the range 10 -5 eV - 20 MeV, including 79 thermal groups below 3 eV. The 129-material library includes processed data for all materials in the ENDF/B-V General Purpose File, several data sets prepared from LENDL data, hydrogen with water- and polyethyelene-bound thermal kernels, deuterium with C 2 O-bound thermal kernels, carbon with a graphite thermal kernel, a special 1/V data set, and a dose factor data set. The library, which is in AMPX master format, is designated CSRL-V (Criticality Safety Reference Library based on ENDF/B-V data). Also included in CSRL-V is a pointwise total, fission, elastic scattering, and (n,γ) cross-section library containing data sets for all ENDF/B-V resonance materials. Data in the pointwise library were processed with the infinite dilute approximation at a temperature of 296 0 K

PARR-2: reactor description and experiments

International Nuclear Information System (INIS)

Wyne, M.F.; Meghji, J.H.

1990-12-01

PARR-2 is a miniature neutron source reactor (MNSR) research reactor has been designed at the rate of 27 kW. Reactor assembly comprises of peaking characteristics with a self limiting flux. In this report reactor description with its assembly and instrumentation control system has been explained. The reactor engineering and physics experiments which can be performed on this reactor are explained in this report. PARR-2 is fueled with HEU fuel pins which are about 90% enriched in U-235. Specific requirements for the safety of the reactor, its building and the personnel, normal instrumentation as required in an industrial environment is sufficient. (A.B.)

Reactor BR2: Introduction

International Nuclear Information System (INIS)

Gubel, P.

2000-01-01

The BR2 reactor is still SCK-CEN's most important nuclear facility. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. A safety audit was conduced by the IAEA, the conclusions of which demonstrated the excellent performance of the plant in terms of operational safety. In 1999, the CALLISTO facility was extensively used for various programmes involving LWR pressure vessel materials, IASCC of LWR structural materials, fusion reactor materials and martensic steels for use in ADS systems. In 1999, BR2's commercial programmes were further developed

Experience with humidity monitoring and leak detection system SMU-V at the Jaslovske Bohunice V-1 NPP

International Nuclear Information System (INIS)

Macko, O.

1996-01-01

Within the paper a brief technical description of SMU-V system is presented including algorithms for measured data evaluation, assessment of experience acquired the system operation and prospective VUEZ activities aimed at the developed of systems for NPP primary circuit leak detection based on humidity monitoring. System SMU-V is used to diagnose dangerous conditions during which integrity of the pipeline could be impaired resulting in absolute humidity increase in the monitored volume. (author)

V.S.O.P. (99/09) computer code system for reactor physics and fuel cycle simulation. Version 2009

Energy Technology Data Exchange (ETDEWEB)

Ruetten, H.J.; Haas, K.A.; Brockmann, H.; Ohlig, U.; Pohl, C.; Scherer, W.

2010-07-15

V.S.O.P. (99/ 09) represents the further development of V.S.O.P. (99/ 05). Compared to its precursor, the code system has been improved again in many details. The main motivation for this new code version was to update the basic nuclear libraries used by the code system. Thus, all cross section libraries involved in the code have now been based on ENDF/B-VII. V.S.O.P. is a computer code system for the comprehensive numerical simulation of the physics of thermal reactors. It implies the setup of the reactor and of the fuel element, processing of cross sections, neutron spectrum evaluation, neutron diffusion calculation in two or three dimensions, fuel burnup, fuel shuffling, reactor control, thermal hydraulics and fuel cycle costs. The thermal hydraulics part (steady state and time-dependent) is restricted to gas-cooled reactors and to two spatial dimensions. The code can simulate the reactor operation from the initial core towards the equilibrium core. This latest code version was developed and tested under the WINDOWS-XP - operating system. (orig.)

V.S.O.P. (99/09) computer code system for reactor physics and fuel cycle simulation. Version 2009

International Nuclear Information System (INIS)

Ruetten, H.J.; Haas, K.A.; Brockmann, H.; Ohlig, U.; Pohl, C.; Scherer, W.

2010-07-01

V.S.O.P. (99/ 09) represents the further development of V.S.O.P. (99/ 05). Compared to its precursor, the code system has been improved again in many details. The main motivation for this new code version was to update the basic nuclear libraries used by the code system. Thus, all cross section libraries involved in the code have now been based on ENDF/B-VII. V.S.O.P. is a computer code system for the comprehensive numerical simulation of the physics of thermal reactors. It implies the setup of the reactor and of the fuel element, processing of cross sections, neutron spectrum evaluation, neutron diffusion calculation in two or three dimensions, fuel burnup, fuel shuffling, reactor control, thermal hydraulics and fuel cycle costs. The thermal hydraulics part (steady state and time-dependent) is restricted to gas-cooled reactors and to two spatial dimensions. The code can simulate the reactor operation from the initial core towards the equilibrium core. This latest code version was developed and tested under the WINDOWS-XP - operating system. (orig.)

Material test reactor fuel research at the BR2 reactor

Energy Technology Data Exchange (ETDEWEB)

Dyck, Steven Van; Koonen, Edgar; Berghe, Sven van den [Institute for Nuclear Materials Science, SCK-CEN, Boeretang, Mol (Belgium)

2012-03-15

The construction of new, high performance material test reactor or the conversion of such reactors' core from high enriched uranium (HEU) to low enriched uranium (LEU) based fuel requires several fuel qualification steps. For the conversion of high performance reactors, high density dispersion or monolithic fuel types are being developed. The Uranium-Molybdenum fuel system has been selected as reference system for the qualification of LEU fuels. For reactors with lower performance characteristics, or as medium enriched fuel for high performance reactors, uranium silicide dispersion fuel is applied. However, on the longer term, the U-Mo based fuel types may offer a more efficient fuel alternative and-or an easier back-end solution with respect to the silicide based fuels. At the BR2 reactor of the Belgian nuclear research center, SCK-CEN in Mol, several types of fuel testing opportunities are present to contribute to such qualification process. A generic validation test for a selected fuel system is the irradiation of flat plates with representative dimensions for a fuel element. By flexible positioning and core loading, bounding irradiation conditions for fuel elements can be performed in a standard device in the BR2. For fuel element designs with curved plates, the element fabrication method compatibility of the fuel type can be addressed by incorporating a set of prototype fuel plates in a mixed driver fuel element of the BR2 reactor. These generic types of tests are performed directly in the primary coolant flow conditions of the BR2 reactor. The experiment control and interpretation is supported by detailed neutronic and thermal-hydraulic modeling of the experiments. Finally, the BR2 reactor offers the flexibility for irradiation of full size prototype fuel elements, as 200mm diameter irradiation channels are available. These channels allow the accommodation of various types of prototype fuel elements, eventually using a dedicated cooling loop to provide the

EBR-2 [Experimental Breeder Reactor-2], IFR [Integral Fast Reactor] prototype testing programs

International Nuclear Information System (INIS)

Lehto, W.K.; Sackett, J.I.; Lindsay, R.W.; Planchon, H.P.; Lambert, J.D.B.

1990-01-01

The Experimental Breeder Reactor-2 (EBR-2) is a sodium cooled power reactor supplying about 20 MWe to the Idaho National Engineering Laboratory (INEL) grid and, in addition, is the key component in the development of the Integral Fast Reactor (IFR). EBR-2's testing capability is extensive and has seen four major phases: (1) demonstration of LMFBR power plant feasibility, (2) irradiation testing for fuel and material development. (3) testing the off-normal performance of fuel and plant systems and (4) operation as the IFR prototype, developing and demonstrating the IFR technology associated with fuel and plant design. Specific programs being carried out in support of the IFR include advanced fuels and materials development and component testing. This paper discusses EBR-2 as the IFR prototype and the associated testing programs. 29 refs

Nuclear and activation characteristics of materials in 14.1-MeV and 2.5-MeV neutron field

International Nuclear Information System (INIS)

Seki, Yasushi; Takeyasu, Yuuichi.

1988-11-01

The nuclear and activation characteristics of various materials and elements of interest in terms of fusion reactor design are calculated and the results are graphically shown. The elements and materials are placed in a simple geometry modelling a blanket and shield of a fusion reactor. The neutrons with 14.1-MeV and 2.5-MeV energy are generated from the region represented as D-T and D-D plasma, respectively. The following activation characteristics after neutron irradiation are shown for each material and element; 1. Time evolution of induced activity, 2. Time evolution of decay heat, 3. Delayed gamma-ray dose distribution, 4. Decay heat distribution. In addition to the above activation characteristics, nuclear characteristics during the neutron irradiation, e.g. neutron energy spectra, neutron and gamma-ray flux distribution, nuclear heating distributions, and neutron and gamma-ray dose rate are also shown. (author)

ASTEC-CATHARE2 benchmarks on French PWR 1300MWe reactors

International Nuclear Information System (INIS)

Tregoures, Nicolas; Philippot, Marc; Foucher, Laurent; Guillard, Gaetan; Fleurot, Joelle

2009-01-01

The French Institut de Radioprotection et de Surete Nucleaire (IRSN) is performing a level 2 Probabilistic Safety Assessment (PSA-2) on the French 1300 MWe reactors. This PSA-2 is heavily relying on the ASTEC integral computer code, jointly developed by IRSN and GRS (Germany). In order to assess the reliability and the quality of physical results of the ASTEC V1.3 code as well as the PWR 1300 MWe reference input deck, an important series of benchmarks with the French best-estimate thermal-hydraulic code CATHARE 2 V2.5 has been performed on 14 different severe accident scenarios. The present paper details 2 out of the 14 studied scenarios: a 12 inches cold leg Loss of Coolant Accident (LOCA) and a 2 tubes Steam Generator Tube Rupture (SGTR). The thermal-hydraulic behavior of the primary and secondary circuits is thoroughly investigated and the ASTEC results of the core degradation phase are presented. Overall, the thermal-hydraulic behavior given by the ASTEC V1.3 is in very good agreement with the CATHARE 2 V2.5 results. (author)

Enel waiting for the state to act first

International Nuclear Information System (INIS)

Anon

2005-01-01

Enel will only answer the basic question whether Slovenske elektrarne will complete the reactors 3 and 4 in nuclear power plant in Mochovce next year. Initial analyses made by Enel indicate that the completion of Mochovce would cost over 60 billions Sk (1,54 billions EUR). Since National Property Fund has approved the strategic investment plan two more conditions have to be met before Enel can acquire Slovenske elektrarne. The first condition is that a part of the company assets has to taken over by state owned joint stock company GovCo. This regards reactor V-1 in nuclear power plant Jaslovske Bohunice that should be made ready for closure by end of 2008, damaged reactor A-1, nuclear equipment decommissioning and disposal unit VYZ and hydroelectric power plant in Gabcikovo. The other condition that still has to be fulfilled is passing of a new act on disposal of nuclear power generating equipment. The new act should distribute the fund's resources amongst the individual nuclear energy sources. M. Arcelli (regional manager of Enel for Slovakia) stresses that the money nuclear power station in Mochovce and V-2 earned and will earn during their time in operation will have to remain in the fund to cover their later liquidation i.e. should not be used on liquidation of reactors V-1 or A-1. (authors)

Reactor BR2. Introduction

International Nuclear Information System (INIS)

Gubel, P.

2001-01-01

The BR2 is a materials testing reactor and is still one of SCK-CEN's important nuclear facilities. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. During the last three years, the availability of the installation was maintained at an average level of 97.6 percent. In the year 2000, the reactor was operated for a total of 104 days at a mean power of 56 MW. In 2000, most irradiation experiments were performed in the CALLISTO PWR loop. The report describes irradiations achieved or under preparation in 2000, including the development of advanced facilities and concept studies for new programmes. An overview of the scientific irradiation programmes as well as of the R and D programme of the BR2 reactor in 2000 is given

Reactor BR2. Introduction

Energy Technology Data Exchange (ETDEWEB)

Gubel, P

2001-04-01

The BR2 is a materials testing reactor and is still one of SCK-CEN's important nuclear facilities. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. During the last three years, the availability of the installation was maintained at an average level of 97.6 percent. In the year 2000, the reactor was operated for a total of 104 days at a mean power of 56 MW. In 2000, most irradiation experiments were performed in the CALLISTO PWR loop. The report describes irradiations achieved or under preparation in 2000, including the development of advanced facilities and concept studies for new programmes. An overview of the scientific irradiation programmes as well as of the R and D programme of the BR2 reactor in 2000 is given.

VAPOR PHASE OXIDATION OF DIMETHYL SULFIDE WITH OZONE OVER V2O5/TIO2 CATALYST

Science.gov (United States)

Removal of volatile and odorous compounds emissions from the pulp and paper industry usually creates secondary pollution for scrubbing and adsorption processes or sulfur poising for catalytic incineration. Product studies performed in a flow reactor packed with 10 % V2O5/TiO2 cat...

Main modelling features of the ASTEC V2.1 major version

International Nuclear Information System (INIS)

Chatelard, P.; Belon, S.; Bosland, L.; Carénini, L.; Coindreau, O.; Cousin, F.; Marchetto, C.; Nowack, H.; Piar, L.; Chailan, L.

2016-01-01

Highlights: • Recent modelling improvements of the ASTEC European severe accident code are outlined. • Key new physical models now available in the ASTEC V2.1 major version are described. • ASTEC progress towards a multi-design reactor code is illustrated for BWR and PHWR. • ASTEC strong link with the on-going EC CESAM FP7 project is emphasized. • Main remaining modelling issues (on which IRSN efforts are now directing) are given. - Abstract: A new major version of the European severe accident integral code ASTEC, developed by IRSN with some GRS support, was delivered in November 2015 to the ASTEC worldwide community. Main modelling features of this V2.1 version are summarised in this paper. In particular, the in-vessel coupling technique between the reactor coolant system thermal-hydraulics module and the core degradation module has been strongly re-engineered to remove some well-known weaknesses of the former V2.0 series. The V2.1 version also includes new core degradation models specifically addressing BWR and PHWR reactor types, as well as several other physical modelling improvements, notably on reflooding of severely damaged cores, Zircaloy oxidation under air atmosphere, corium coolability during corium concrete interaction and source term evaluation. Moreover, this V2.1 version constitutes the back-bone of the CESAM FP7 project, which final objective is to further improve ASTEC for use in Severe Accident Management analysis of the Gen.II–III nuclear power plants presently under operation or foreseen in near future in Europe. As part of this European project, IRSN efforts to continuously improve both code numerical robustness and computing performances at plant scale as well as users’ tools are being intensified. Besides, ASTEC will continue capitalising the whole knowledge on severe accidents phenomenology by progressively keeping physical models at the state of the art through a regular feed-back from the interpretation of the current and

Calculational experimental examination and ensuring of equipment and pipelines seismic resistance at starting and operating water-cooled and moderated reactor WWER-type NPPs. Final report

International Nuclear Information System (INIS)

1999-01-01

The results of testing of equipment at Bohunice NPP and pipeline systems at Unit 3 of Kozloduy NPP (WWER-440 type reactors) are presented in this Final Report. These results side by side with experimental values of natural frequencies and decrements also include experimental data about vibration modes of tested equipment and pipelines. For the first time the results of new calculational-experimental examination of equipment seismic resistance at Unit 2 of Armenian NPP are presented. At Kozloduy NPP direction's request the planed additional tests of some selected items were put off on 1997. Instead of postponed tests we carried out detailed analysis of our past inspections of numerous equipment seismic resistance at the Unit 5 of Kozloduy NPP. Experimental data with results of additional analysis are presented

Preparation for and building of V-1 nuclear power plant

International Nuclear Information System (INIS)

Smatlak, S.; Spirko, M.

1981-01-01

Some findings and problems encountered during the construction of the V-1 nuclear power plant at Jaslovske Bohunice are discussed from the point of view of the investor, mainly problems associated with project preparation and relations between suppliers and the customer. The progress of construction is described and the dates are shown of the main stages of construction and tests. The construction proceeded according to a net diagram and was controlled by the construction management and a coordination group headed by the investor. An international start-up commission was established for the start-up stage. The fields are outlined of the participation and co-operation of Soviet organizations during project preparation, supplies, assembly, start-up, and fuel supplies for the V-1 nuclear power plant. (B.S.)

Software V and V of PPS for Shin-Hanul Nuclear Power Plant Units 1 and 2

International Nuclear Information System (INIS)

Park, Cheollak; Kang, Dongpa; Choe, Changhui; Sohn, Sedo; Beak, Seungmin

2013-01-01

Software V and V processes determine whether the development products of a given activity conform to the requirements of that activity and whether the software satisfies its intended use and user needs. This paper introduces the software V and V activities and tasks performed during the software development life cycle performed during the software development life cycle of the Plant Protection System (PPS) for Shin-Hanul Nuclear Power Plant Units 1 and 2 (SHN 1 and 2). The PPS generates signals to actuate Reactor Trip (RT) and Engineered Safety Features (ESF) whenever monitored processes exceed predetermined limits, and the PPS software is classified safety critical and an independent V and V is thus required according to regulations, code and standards. The software V and V efforts, sufficiently disciplined and rigorous, are quite essential to demonstrate that the software development process is of a high quality. The software V and V of PPS for SHN 1 and 2 has been accomplished successfully with systematic V and V procedures and methods established until test phase in compliance with related code and standards. In particular, the use of automated tools such as LDRA and DOORS greatly has contributed to an improvement of a software quality, and a reduction of a verification time and human errors

Safety features of TR-2 reactor

International Nuclear Information System (INIS)

Tuerker, T.

2001-01-01

TR-2 is a swimming pool type research reactor with 5 MW thermal power and uses standard MTR plate type fuel elements. Each standard fuel element consist of 23 fuel plates with a meat + cladding thickness of 0.127 cm, coolant channel clearance is 0.21 cm. Originally TR-2 is designed for %93 enriched U-Al. Alloy fuel meat.This work is based on the preparation of the Final Safety Analyses Report (FSAR) of the TR-2 reactor. The main aspect is to investigate the behaviour of TR-2 reactor under the accident and abnormal operating conditions, which cowers the accident spectrum unique for the TR-2 reactor. This presentation covers some selected transient analyses which are important for the safety aspects of the TR-2 reactor like reactivity induced startup accidents, pump coast down (Loss of Flow Accident, LOFA) and other accidents which are charecteristic to the TR-2

Switching Overvoltages in 60 kV reactor compensated cable grid due to resonance after disconnection

DEFF Research Database (Denmark)

Bak, Claus Leth; Baldursson, Haukur; Oumarou, Abdoul M.

2008-01-01

power could be directly connected to long cables. Switching both cable and reactor together will cause resonance to occur between the cable capacitance and the inductance of the cable during last end disconnection. Similar type of resonance condition is known to have caused switching overvoltages...... on the 400kV grid in Denmark. Therefore it is considered necessary to analyze further whether connecting a reactor directly to 60kV cable can cause switching overvoltages. A model in PSCAD was used to analyze which parameters can cause overvoltage. The switching resonance overvoltage was found to be caused...

Reactor BR2. Introduction

International Nuclear Information System (INIS)

Gubel, P.

2002-01-01

The BR2 materials testing reactor is one of SCK-CEN's most important nuclear facilities. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. In 2001, the reactor was operated for a total of 123 days at a mean power of 59 MW in order to satisfy the irradiation conditions of the internal and external programmes using mainly the CALLISTO PWR loop. The mean consumption of fresh fuel elements was 5.26 per 1000 MWd. Main achievements in 2001 included the development of a three-dimensional full-scale model of the BR2 reactor for simulation and prediction of irradiation conditions for various experiments; the construction of the FUTURE-MT device designed for the irradiation of fuel plates under representative conditions of geometry, neutron spectrum, heat flux and thermal-hydraulic conditions and the development of in-pile instrumentation and a data acquisition system

Reactor BR2. Introduction

Energy Technology Data Exchange (ETDEWEB)

Gubel, P

2002-04-01

The BR2 materials testing reactor is one of SCK-CEN's most important nuclear facilities. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. In 2001, the reactor was operated for a total of 123 days at a mean power of 59 MW in order to satisfy the irradiation conditions of the internal and external programmes using mainly the CALLISTO PWR loop. The mean consumption of fresh fuel elements was 5.26 per 1000 MWd. Main achievements in 2001 included the development of a three-dimensional full-scale model of the BR2 reactor for simulation and prediction of irradiation conditions for various experiments; the construction of the FUTURE-MT device designed for the irradiation of fuel plates under representative conditions of geometry, neutron spectrum, heat flux and thermal-hydraulic conditions and the development of in-pile instrumentation and a data acquisition system.

2 keV filters of quasi-mono-energetic neutrons

International Nuclear Information System (INIS)

Adib, M.; Habib, N.; El-Mesiry, M.S.; Bashter, I.I.; Saleh, A.; Fathallah, M.

2013-01-01

A simulation study for the production of 2 keV filters of quasi-mono-energetic neutrons based on the deep interference minima in the 45 Sc total cross-section was carried out. A computer code QMENF-II was adapted to calculate the optimum amounts of the 45 Sc as a main filter element and additional component ones to obtain sufficient intensity at high resolution and purity of the filtered quasi-mono-energetic neutrons. The emitted neutron spectrum from nuclear reactor and from the reaction of 2.6 MeV protons on a lithium fluoride target at the accelerator beam port, are used for simulation

Jevgenij V. Doc: We do not want to build a monument at Mochovce

International Nuclear Information System (INIS)

Janoska, J.

2004-01-01

In this paper the interview with the General Manager of Inter RAO JES - Jevgenij V. Doc is published. Inter RAO JES applies for the privatisation of Slovenske elektrarne (Slovak Electric - SE). According to the General Manager of Inter RAO JES, the company does not need a foreign partner to provide financial support after the privatisation of SE, but rather it requires a political support. Plans about Bohunice NPP and of completion of the Mochovce NPP as well as of privatisation of the SE by the Inter RAO JES are presented

BR2 Reactor: Introduction

International Nuclear Information System (INIS)

Moons, F.

2007-01-01

The irradiations in the BR2 reactor are in collaboration with or at the request of third parties such as the European Commission, the IAEA, research centres and utilities, reactor vendors or fuel manufacturers. The reactor also contributes significantly to the production of radioisotopes for medical and industrial applications, to neutron silicon doping for the semiconductor industry and to scientific irradiations for universities. Along the ongoing programmes on fuel and materials development, several new irradiation devices are in use or in design. Amongst others a loop providing enhanced cooling for novel materials testing reactor fuel, a device for high temperature gas cooled fuel as well as a rig for the irradiation of metallurgical samples in a Pb-Bi environment. A full scale 3-D heterogeneous model of BR2 is available. The model describes the real hyperbolic arrangement of the reactor and includes the detailed 3-D space dependent distribution of the isotopic fuel depletion in the fuel elements. The model is validated on the reactivity measurements of several tens of BR2 operation cycles. The accurate calculations of the axial and radial distributions of the poisoning of the beryllium matrix by 3 He, 6 Li and 3T are verified on the measured reactivity losses used to predict the reactivity behavior for the coming decades. The model calculates the main functionals in reactor physics like: conventional thermal and equivalent fission neutron fluxes, number of displacements per atom, fission rate, thermal power characteristics as heat flux and linear power density, neutron/gamma heating, determination of the fission energy deposited in fuel plates/rods, neutron multiplication factor and fuel burn-up. For each reactor irradiation project, a detailed geometry model of the experimental device and of its neighborhood is developed. Neutron fluxes are predicted within approximately 10 percent in comparison with the dosimetry measurements. Fission rate, heat flux and

Fissile fuel production and usage of thermal reactor waste fueled with UO2 by means of hybrid reactor system

International Nuclear Information System (INIS)

Ipek, O.

1997-01-01

The use of Fast Breeder Reactors to produce fissile fuel from nuclear waste and the operation of these reactors with a new neutron source are becoming today' topic. In the thermonuclear reactors, it is possible to use 2.45-14.1 MeV - neutrons which can be obtained by D-T, D-D Semicatalyzed (D-D) and other fusion reactions. To be able to do these, Hybrid Reactor System, which still has experimental and theoretical studies, have to be taken into consideration.In this study, neutronic analysis of hybrid blanket with grafit reflector, is performed. D-T driven fusion reaction is surrounded by UO 2 fuel layer and the production of ''2''3''9Pu fissile fuel from waste ''2''3''8U is analyzed. It is also compared to the other possible fusion reactions. The results show that 815.8 kg/year ''2''3''8Pu with D-T reaction and 1431.6 kg/year ''2''3''8Pu with semicatalyzed (D-D) reaction can be produced for 1000 MW fusion power. This means production of 2.8/ year and 4.94/ year LWR respectively. In addition, 1000 MW fusion flower is is multiplicated to 3415 MW and 4274 MW for D-T and semicatalyzed (D-D) reactions respectively. The system works subcritical and these values are 0.4115 and 0.312 in order. The calculations, ANISN-ORNL code, S 16 -P 3 approach and DLC36 data library are used

Preparation and benchmarking of ANSL-V cross sections for advanced neutron source reactor studies

International Nuclear Information System (INIS)

Arwood, J.W.; Ford, W.E. III; Greene, N.M.; Petrie, L.M.; Primm, R.T. III; Waddell, M.W.; Webster, C.C.; Westfall, R.M.; Wright, R.Q.

1987-01-01

Research and development for the advanced neutron source (ANS) reactor is being funded by the US Dept. of Energy. This reactor is to provide the world's most intense steady-state source of low-energy neutrons for a national experimental user facility. Pseudo-problem-independent, multigroup cross-section libraries were generated to support ANS design work. The libraries, designated ANSL-V, are data bases in AMPX master format for subsequent generation of problem-dependent cross sections for use with codes such as KENO, ANISN, XSDRNPM, VENTURE, DOT, and MORSE. Included in ANSL-V are 123-material P 3 neutron, 46-material P 0 or P 6 secondary gamma-ray production (SGRP), and 34-material P 6 gamma-ray interaction (GRI) libraries

The BR2 materials testing reactor. Past, ongoing and under-study upgradings

Energy Technology Data Exchange (ETDEWEB)

Baugnet, J M; Roedt, Ch de; Gubel, P; Koonen, E [Centre d' Etude de I' Energie Nucleaire, Studiecentrum voor Kernenergie, C.E.N./S.C.K., Mol (Belgium)

1990-05-01

The BR2 reactor (Mol, Belgium) is a high-flux materials testing reactor. The fuel is 93% {sup 235}U enriched uranium. The nominal power ranges from 60 to 100 MW. The main features of the design are the following: 1) maximum neutron flux, thermal: 1.2 x 10{sup 15} n/cm{sup 2} s; fast (E > 0.1 MeV) : 8.4 x 10{sup 14} n /cm{sup 2} s; 2) great flexibility of utilization: the core configuration and operation mode can be adapted to the experimental loading; 3) neutron spectrum tailoring; 4) availability of five 200 mm diameter channels besides the standard channels (84 mm diameter); 5) access to the top and bottom covers of the reactor authorizing the irradiation of loops. The reactor is used to study the behaviour of fuel elements and structural materials intended for future nuclear power stations of several types (fission and fusion). Irradiations are carried out in connection with performance tests up to very high burn-up or neutron fluence as well as for safety experiments, power cycling experiments, and generally speaking, tests under off-normal conditions. Irradiations for nuclear transmutation (production of high specific activity radio-isotopes and transplutonium elements), neutron-radiography, use of beam tubes for physics studies, and gamma irradiations are also carried out. The BR2 is used in support of Belgian programs, at the request of utilities, industry and universities and in the framework of international agreements. The paper reviews the past and ongoing upgrading and enhancement of reactor capabilities as well as those under study or consideration, namely with regard to: reactor equipment, fuel elements, irradiation facilities, reactor operation conditions and long-term strategy. (author)

Reactor plant for Belene NPP completion

International Nuclear Information System (INIS)

Dragunov, Yu. G.; Ryzhov, S. B.; Ermakov, D. N.; Repin, A. I.

2004-01-01

Construction of 'Belene' NPP was started at the end of 80-ties using project U-87 with V-320 reactor plant, general designer of this plant is OKB 'Gidropress'. At the beginning of 90-ties, on completing the considerable number of deliveries and performance of civil engineering work at the site the NPP construction was suspended. Nowadays, considering the state of affairs at the site and the work performed by Bulgarian Party on preservation of the equipment delivered, the most perspective is supposed to be implementation of the following versions in completing 'Belene' NPP: for completion of Unit 1 - reactor plant VVER-1000 on the basis of V-320 reactor with the maximum use of the delivered equipment (V-320M) having the extended service life and safety improvement; for Unit 2 - advanced reactor plant VVER-1000. For the upgraded reactor plant V-230M the basic solutions and characteristics are presented, as well as the calculated justification of strength and safety analyses, design of the reactor core and fuel cycle, instrumentation and control systems, application of the 'leak-before break' in the project and implementation of safety measures. For the modernised reactor plant V-392M the main characteristics and basic changes are presented, concerning reactor pressure vessel, steam generator, reactor coolant pump set. Design of NPP with the modernized reactor plant V-320M meets the up-to-date requirements and can be licensed for completion and operation. In the design of NPP with the advanced reactor plant the basic solutions and the equipment are used that are similar to those used in standard reactor plant V-320 and new one with VVER-1000 under construction and completion in Russia, and abroad. Compliance of reactor design with the up-to-date international requirements, considering the extended service life of the main equipment, shows its rather high potential for implementation during completion of 'Belene' NPP

Design basis and design features of WWER-440 model 213 nuclear power plants. Reference plant: Bohunice V2 (Slovakia)

International Nuclear Information System (INIS)

1994-05-01

The prime objective of the IAEA Technical Co-operation Project on Evaluation of Safety Aspects of WWER-440 model 213 NPPs is to co-ordinate and to integrate assistance to national organizations in studying selected aspects of safety for the same type of reactors. Consequently, the study integrated the results generated by national activities carried out in the Czech Republic, Hungary, Slovakia and Ukraine and co-ordinated through the IAEA. Valuable assistance in carrying out the tasks was also provided by Bulgaria and Poland. A set of publications is being prepared to present the results of the project. The publications are intended to facilitate the review and utilization of the results of the project. They are also providing assistance in further refinement and/or extension of plant specific safety evaluation of model 213 NPPs. This Technical Document addressing the design basis and safety related design features of WWER-440 model 213 plants is the first of the series to be published. It is hoped that this document will be useful to anyone working in the field of WWER safety, and in particular to experts planning, executing or reviewing studies related to the subject. Refs, 36 figs, tabs

Application of MCNPX 2.7.D for reactor core management at the research reactor BR2

International Nuclear Information System (INIS)

Kalcheva, Silva; Koonen, Edgar

2011-01-01

The paper discusses application of the Monte Carlo burn up code MCNPX 2.7.D for whole core criticality and depletion analysis of the Material Testing Research Reactor BR2 at SCK-CEN in Mol, Belgium. Two different approaches in the use of MCNPX 2.7.D are presented. The first methodology couples the evolution of fuel depletion, evaluated by MCNPX 2.7.D in an infinite lattice with a steady-state 3-D power distribution in the full core model. The second method represents fully automatic whole core depletion and criticality calculations in the detailed 3-D heterogeneous geometry model of the BR2 reactor. The accuracy of the method and computational time as function of the number of used unique burn up materials in the model are being studied. The depletion capabilities of MCNPX 2.7.D are compared vs. the developed at the BR2 reactor department MCNPX & ORIGEN-S combined method. Testing of MCNPX 2.7.D on the criticality measurements at the BR2 reactor is presented. (author)

Homogeneous SLOWPOKE reactors for replacing SLOWPOKE-2 research reactors and the production of radioisotopes

International Nuclear Information System (INIS)

Bonin, H.W.; Hilborn, J.W.; Carlin, G.E.; Gagnon, R.; Busatta, P.

2014-01-01

Inspired from the inherently safe SLOWPOKE-2 research reactor, the Homogeneous SLOWPOKE reactor was conceived with a double goal: replacing the heterogeneous SLOWPOKE-2 reactors when they reach end-of-core life to continue their missions of neutron activation analysis and neutron radiography at universities, and to produce radioisotopes such as 99 Mo for medical applications. A homogeneous reactor core allows a much simpler extraction of radioisotopes (such as 99 Mo) for applications in industry and nuclear medicine. The 20 kW Homogeneous SLOWPOKE reactor was modelled using both the deterministic WIMS-AECL and the probabilistic MCNP 5 reactor simulation codes. The homogeneous fuel mixture was a dilute aqueous solution of Uranyl Sulfate (UO 2 SO 4 ) with 994.2 g of 235 U (enrichment at 20%) providing an excess reactivity at operating temperature (40 o C) of 3.8 mk for a molality determined as 1.46 mol kg -1 for a Zircaloy-2 reactor vessel. Because this reactor is intended to replace the core of SLOWPOKE-2 reactors, the Homogeneous SLOWPOKE reactor core had a height about twice its diameter. The reactor could be controlled by mechanical absorber rods in the beryllium reflector, chemical control in the core, or a combination of both. The safety of the Homogeneous SLOWPOKE reactor was analysed for both normal operation and transient conditions. Thermal-hydraulics calculations used COMSOL Multiphysics and the results showed that natural convection was sufficient to ensure adequate reactor cooling in all situations. The most severe transient simulated resulted from a 5.87 mk step positive reactivity insertion to the reactor in operation at critical and at steady state at 20 o C. Peak temperature and power were determined as 83 o C and 546 kW, respectively, reached 5.1 s after the reactivity insertion. However, the power fell rapidly to values below 20 kW some 35 s after the peak and remained below that value thereafter. Both the temperature and void coefficients are

Homogeneous SLOWPOKE reactors for replacing SLOWPOKE-2 research reactors and the production of radioisotopes

Energy Technology Data Exchange (ETDEWEB)

Bonin, H.W., E-mail: bonin-h@rmc.ca [Royal Military College of Canada, Kingston, Ontario (Canada); Hilborn, J.W. [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada); Carlin, G.E. [Ontario Power Generation, Toronto, Ontario (Canada); Gagnon, R.; Busatta, P. [Canadian Forces (Canada)

2014-07-01

Inspired from the inherently safe SLOWPOKE-2 research reactor, the Homogeneous SLOWPOKE reactor was conceived with a double goal: replacing the heterogeneous SLOWPOKE-2 reactors when they reach end-of-core life to continue their missions of neutron activation analysis and neutron radiography at universities, and to produce radioisotopes such as {sup 99}Mo for medical applications. A homogeneous reactor core allows a much simpler extraction of radioisotopes (such as {sup 99}Mo) for applications in industry and nuclear medicine. The 20 kW Homogeneous SLOWPOKE reactor was modelled using both the deterministic WIMS-AECL and the probabilistic MCNP 5 reactor simulation codes. The homogeneous fuel mixture was a dilute aqueous solution of Uranyl Sulfate (UO{sub 2}SO{sub 4}) with 994.2 g of {sup 235}U (enrichment at 20%) providing an excess reactivity at operating temperature (40 {sup o}C) of 3.8 mk for a molality determined as 1.46 mol kg{sup -1} for a Zircaloy-2 reactor vessel. Because this reactor is intended to replace the core of SLOWPOKE-2 reactors, the Homogeneous SLOWPOKE reactor core had a height about twice its diameter. The reactor could be controlled by mechanical absorber rods in the beryllium reflector, chemical control in the core, or a combination of both. The safety of the Homogeneous SLOWPOKE reactor was analysed for both normal operation and transient conditions. Thermal-hydraulics calculations used COMSOL Multiphysics and the results showed that natural convection was sufficient to ensure adequate reactor cooling in all situations. The most severe transient simulated resulted from a 5.87 mk step positive reactivity insertion to the reactor in operation at critical and at steady state at 20 {sup o}C. Peak temperature and power were determined as 83 {sup o}C and 546 kW, respectively, reached 5.1 s after the reactivity insertion. However, the power fell rapidly to values below 20 kW some 35 s after the peak and remained below that value thereafter. Both the

Further study on parameterization of reactor NAA: Pt. 2

International Nuclear Information System (INIS)

Tian Weizhi; Zhang Shuxin

1989-01-01

In the last paper, Ik 0 method was proposed for fission interference corrections. Another important kind of interferences in reator NAA is due to threshold reaction induced by reactor fast neutrons. In view of the increasing importance of this kind of interferences, and difficulties encountered in using the relative comparison method, a parameterized method has been introduced. Typical channels in heavy water reflector and No.2 horizontal channel of Heavy Water Research Reactor in the Insitute of Atomic Energy have been shown to have fast neutron energy distributions (E>4 MeV) close to primary fission neutron spectrum, by using multi-threshold detectors. On this basis, Ti foil is used as an 'instant fast neutron flux monitor' in parameterized corrections for threshold reaction interferences in the long irradiations. Constant values of φ f /φ s = 0.70 ± 0.02% have been obtained for No.2 rabbit channel. This value can be directly used for threshold reaction inference correction in the short irradiations

Theoretical analysis of nuclear reactors (Phase I), I-V, Part V, Determining the fine flux distribution

International Nuclear Information System (INIS)

Pop-Jordanov, J.

1962-07-01

Mono energetic neutron transport equation was solved by Carlson numerical method in cylindrical geometry. S n code was developed for the digital computer ZUSE Z23. Neutron flux distribution was determined for the RA reactor cell by applying S 4 approximation. Reactor cell was treated as D 2 O-U-D 2 O system. Time of iteration was 185 s [sr

Introductory speeches

International Nuclear Information System (INIS)

2001-01-01

This CD is multimedia presentation of programme safety upgrading of Bohunice V1 NPP. This chapter consist of introductory commentary and 4 introductory speeches (video records): (1) Introductory speech of Vincent Pillar, Board chairman and director general of Slovak electric, Plc. (SE); (2) Introductory speech of Stefan Schmidt, director of SE - Bohunice Nuclear power plants; (3) Introductory speech of Jan Korec, Board chairman and director general of VUJE Trnava, Inc. - Engineering, Design and Research Organisation, Trnava; Introductory speech of Dietrich Kuschel, Senior vice-president of FRAMATOME ANP Project and Engineering

Fusion reactor problems

International Nuclear Information System (INIS)

Carruthers, R.

It is pointed out that plasma parameters for a fusion reactor have been fairly accurately defined for many years, and the real plasma physics objective must be to find the means of achieving and maintaining these specifiable parameters. There is good understanding of the generic technological problems: breading blankets and shields, radiation damage, heat transfer and methods of magnet design. The required plasma parameters for fusion self-heated reactors are established at ntausub(E) approximately 2.10 14 cm -3 sec, plasma radius 1.5 to 3 m, wall loading 5 to 10 MW cm -2 , temperature 15 keV. Within this model plasma control by quasi-steady burn as a key problem is studied. It is emphasized that the future programme must interact more closely with engineering studies and should concentrate upon research which is relevant to reactor plasmas. (V.P.)

Advanced Neutron Source Cross Section Libraries (ANSL-V): ENDF/B-V based multigroup cross-section libraries for advanced neutron source (ANS) reactor studies

International Nuclear Information System (INIS)

Ford, W.E. III; Arwood, J.W.; Greene, N.M.; Moses, D.L.; Petrie, L.M.; Primm, R.T. III; Slater, C.O.; Westfall, R.M.; Wright, R.Q.

1990-09-01

Pseudo-problem-independent, multigroup cross-section libraries were generated to support Advanced Neutron Source (ANS) Reactor design studies. The ANS is a proposed reactor which would be fueled with highly enriched uranium and cooled with heavy water. The libraries, designated ANSL-V (Advanced Neutron Source Cross Section Libraries based on ENDF/B-V), are data bases in AMPX master format for subsequent generation of problem-dependent cross-sections for use with codes such as KENO, ANISN, XSDRNPM, VENTURE, DOT, DORT, TORT, and MORSE. Included in ANSL-V are 99-group and 39-group neutron, 39-neutron-group 44-gamma-ray-group secondary gamma-ray production (SGRP), 44-group gamma-ray interaction (GRI), and coupled, 39-neutron group 44-gamma-ray group (CNG) cross-section libraries. The neutron and SGRP libraries were generated primarily from ENDF/B-V data; the GRI library was generated from DLC-99/HUGO data, which is recognized as the ENDF/B-V photon interaction data. Modules from the AMPX and NJOY systems were used to process the multigroup data. Validity of selected data from the fine- and broad-group neutron libraries was satisfactorily tested in performance parameter calculations

CO2 Energy Reactor - Integrated Mineral Carbonation: Perspectives on Lab-Scale Investigation and Products Valorization

OpenAIRE

Rafael M Santos; Pol CM Knops; Keesjan L Rijnsburger; Yi Wai eChiang

2016-01-01

To overcome the challenges of mineral CO2 sequestration, Innovation Concepts B.V. is developing a unique proprietary gravity pressure vessel (GPV) reactor technology and has focussed on generating reaction products of high economic value. The GPV provides intense process conditions through hydrostatic pressurization and heat exchange integration that harvests exothermic reaction energy, thereby reducing energy demand of conventional reactor designs, in addition to offering other benefits. In ...

Accident localization system with jet condensers for VVER 440-V 230 NPP at Jaslovske Bohunice

International Nuclear Information System (INIS)

Murani, J.

1995-01-01

The operational safety of the V1 nuclear power plant (NPP) is unsatisfactory and does not correspond to present requirements as to nuclear safety. Further NPP operation after 1995 is conditional on nuclear safety enhancement to a level comparable with that in West European countries. This aim should be achieved by a principal reconstruction involving in addition to others also backfitting the V1 NPP with technical facilities aimed at coping with a design basis accident (DBA).To cope with such an accident the Power Equipment Research Institute (VUEZ) designed an accident localization system with jet condensers. This system consists of (a) an air trap (one for each unit, mutually interconnected) with an expansion bell enclosed within, placed on a plate with 200 pipes of jet condensers passing through, and (b) a connecting duct between the hermetic zone and the air trap. The vertical jet condenser is an essential element of the system designed for steam condensation. Apart from condensation it serves as a water seal separating units 1 and 2.Demonstration tests of the jet condenser (model 1:1) condensing function were carried out at the testing unit of the All-Union Research Institute for NPP Operation (VNIIAES), Moscow in Kashir, 11-22 September 1992. These experiments proved the jet condenser ability to ensure complete condensation of the steam produced. Experimental verification of the sealing function (model 1:1) was carried out at the testing unit of the VUEZ Tlmace. These experiments concerning the dynamics and overpressure in the free space above the pool were close to the conditions in the air trap during DBA. The jet condenser height was proved to be sufficient to ensure the sealing function. Design and experimental work has been implemented in close cooperation with Russian experts Mr. V.N. Bulynin from the VNIIAES, Moscow, and Mr. M.V. Kuznecov from the Scientific and Engineering Center for Nuclear and Radiological Safety, Moscow. (orig.)

A comparison of the free vacancy production in α brass by fission reactor neutrons and 14.8-MeV neutrons

International Nuclear Information System (INIS)

Damask, A.C.; Van Konynenburg, R.; Borg, R.J.; Dienes, G.J.

1976-01-01

Enhancement of substitutional diffusion is observed in α brass (30 wt% Zn) by following the decrease in electrical resistivity with neutron irradiation of a thermally equilibrated alloy; the decrease arises from the increase in short-range order. It was determined by previous research that this diffusion enhancement is largely caused by the annealling of radiation-produced vacancies in excess of the thermal equilibrium concentration. Therefore, the results reported here are based upon a well-established technique. The rate of resistivity change per neutron of different energies will give the relative number of free vacancies produced per neutron. This experiment compares the effect of 14.8 MeV neutrons with neutrons from a fission reactor. The results indicate that 14.8 MeV neutrons produce 10 +- 2 times as many free vacancies as reactor neutrons when the latter are expressed in terms of those neutrons with energies greater than 0.1 MeV. (author)

Core monitoring at the WNP-2 reactor

International Nuclear Information System (INIS)

Skeen, D.R.; Torres, R.H.; Burke, W.J.; Jenkins, I.; Jones, S.W.

1992-01-01

The WNP-2 reactor is a 3,323-MW(thermal) boiling water reactor (BWR) that is operated by the Washington Public Power Supply System. The WNP-2 reactor began commercial operation in 1984 and is currently in its eighth cycle. The core monitoring system used for the first cycle of operation was supplied by the reactor vendor. Cycles 2 through 6 were monitored with the POWERPLEX Core Monitoring Software System (CMSS) using the XTGBWR simulation code. In 1991, the supply system upgraded the core monitoring system by installing the POWERPLEX 2 CMSS prior to the seventh cycle of operation for WNP-2. The POWERPLEX 2 CMSS was developed by Siemens Power Corporation (SPC) and is based on SPC's advanced state-of-the-art reactor simulator code MICROBURN-B. The improvements in the POWERPLEX 2 system are possible as a result of advances in minicomputer hardware

Change of I-V characteristics of SiC diodes upon reactor irradiation; Modification des caracteristiques I-V de jonctions p-n au SiC du fait d'une irradiation dans un reacteur; Izmeneniya kharakteristik I-V vyrashchennogo v SiC perekhoda tipa p-n posle oblucheniya ego v reaktore; Modificaciones que sufren por irradiacion en un reactor las caracteristicas I-V de uniones p-n en SiC

Energy Technology Data Exchange (ETDEWEB)

Heerschap, M; De Coninck, R [Solid State Physics Dept., SCK-CEN, Mol (Belgium)

1962-04-15

In search for semiconductors, which can be used in high-flux reactors in order to measure flux distributions, we irradiated SiC p-n junctions in the Belgium BR-1 reactor. Two types of SiC-diodes of different origin have been irradiated. These junctions are grown in the Lely-furnace. The change in forward and reverse characteristics have been measured during and after irradiation up to temperatures of 150{sup o}C, while measurements up to a temperature of 500{sup o}C are in progress. It has been found that one type resists BR-1 neutrons up to an integrated flux of 10{sup 15} n/cm{sup 2}, while the other resists irradiation up to a flux of 10{sup 17} n/cm{sup 2}. The changes in characteristics are given as well as the result of some annealing experiments. (author) [French] En recherchant des semi-conducteurs pouvant servir a mesurer les distributions de flux dans les reacteurs a haut flux de neutrons, les auteurs ont irradie des jonctions p-n au SiC dans le reacteur belge BR-1. Deux types de diodes a SiC d'origines differentes ont ete ainsi irradies. Les jonctions en question sont preparees par etirage dans le four Lely. Les auteurs ont mesure les modifications subies par les caracteristiques I-V apres et pendant l'irradiation a des temperatures allant jusqu'a 150{sup o}C; ils poursuivent leurs mesures dans la gamme des temperatures allant de 150{sup o}C a 500{sup o}C. Us ont constate que l'un des types de diode a SiC resiste aux neutrons du reacteur BR-1 jusqu'a 10{sup 15} n/cm{sup 2}, tandis que l'autre type resiste a l'irradiation jusqu'a 10{sup 17} n/cm{sup 2}. Les auteurs indiquent les modifications subies par les caracteristiques, ainsi que le resultat de certaines experiences de recuit. (author) [Spanish] Los autores estan tratando de encontrar semiconductores con los que sea posible medir distribuciones de flujo en reactores de flujo elevado, y con este fin irradiaron uniones p-n del SiC en el reactor BR-1 de Belgica. Irradiaron dos tipos de diodos de SiC de

TA-2 Water Boiler Reactor Decommissioning Project

International Nuclear Information System (INIS)

Durbin, M.E.; Montoya, G.M.

1991-06-01

This final report addresses the Phase 2 decommissioning of the Water Boiler Reactor, biological shield, other components within the biological shield, and piping pits in the floor of the reactor building. External structures and underground piping associated with the gaseous effluent (stack) line from Technical Area 2 (TA-2) Water Boiler Reactor were removed in 1985--1986 as Phase 1 of reactor decommissioning. The cost of Phase 2 was approximately $623K. The decommissioning operation produced 173 m 3 of low-level solid radioactive waste and 35 m 3 of mixed waste. 15 refs., 25 figs., 3 tabs

Monitoring of primary circuit and reactor of NPP A-1

International Nuclear Information System (INIS)

Prazska, M.; Majersky, M.; Rezbarik, J.; Sekely, S.; Vozarik, P.; Walthery, R.; Stuller, P.

2005-01-01

Nuclear Power Plant A-1 in Jaslovske Bohunice was commissioned in 1972. Heavy water moderated, carbon dioxide cooled channel type reactor was shut down after two accidents in 1977. During more serious second accident, the reduced coolant flow caused local overheating of the fuel and consequent damage/melting of the fuel channel. Both accidents had led to the damage of several fuel assemblies with extensive local damage of fuel claddings. As a consequence, the main cooling circuit was significantly contaminated by fission products and long-life alpha nuclides. The detailed monitoring of dose rates, smearable contamination and sampling of contamination was performed. Extended monitoring in reacto vessel, primary circuit pipes, turbo-compressors, steam generators, main valves, gas tanks and also heavy water system with collectors, coolers, distilling and purification station, pumps and valves was done. Appropriate devices and procedures for the monitoring and examination of the installations were prepared and applied. Obtained results will serve for the future planning of the decontamination and decommissioning works. The 3-D model of the reactor that had been developed as part of this Project proved invaluable for orientation, visualisation, planning and analysis of results. Dose rates were measured in the technological channels from the reactor hall floor to the bottom of the hot gas chamber in decrements of 1 m and 0.5 m. The highest absolute values of dose rates were found in channels located in the middle of the reactor (up to 1900 mGy/h in the active zone region). It is estimated that the total contaminated area of primary circuit equipment (pipework, steam generators and turbo-compressors) is some 48 000 m 2 . It follows that the total gamma contamination is of the order of 10 14 to 10 15 Bq and total alpha contamination 10 11 to 10 13 Bq. The total amount of deposits in the gas circuit is about 14.3 tons. (authors)

Independent CO{sub 2} loop for cooling the samples irradiated in the RA reactor vertical experimental channels, Task 2.50.05; Nezavisno kolo CO{sub 2} za hladjenje uzoraka ozracivanih u vertikalnim eksperimentalnim kanalima reaktora RA, Zad. 2.50.05

Energy Technology Data Exchange (ETDEWEB)

Stojic, M; Pavicevic, M

1964-07-01

This report contains the following volumes V and VI of the Project 'Independent CO{sub 2} loop for cooling the samples irradiated in RA reactor vertical experimental channels': Design project of the dosimetry control system in the independent CO{sub 2} loop for cooling the samples irradiated in the RA reactor vertical experimental channels, and Safety report for the Independent CO{sub 2} loop for cooling the samples irradiated in the RA reactor vertical experimental channels. Ovaj izvestaj sadrzi dva albuma zadatka 'Nezavisno kolo CO{sub 2} za hladjenje uzoraka ozracivanih u vertikalnim eksperimentalnim kanalima reaktora RA', Zad. 2.50.05: Album V: Predprojekat sistema dozimetrijske kontrole u nezavisnom kolu CO{sub 2} za hladjenje uzoraka ozracivanih u VEK reaktora RA i Album VI: Izvestaj o sigurnosti za nezavisno kolo CO{sub 2} za hladjenje uzoraka ozracivanih u VEK reaktora RA.

EBR-2 [Experimental Breeder Reactor-2] test programs

International Nuclear Information System (INIS)

Sackett, J.I.; Lehto, W.K.; Lindsay, R.W.; Planchon, H.P.; Lambert, J.D.B.; Hill, D.J.

1990-01-01

The Experimental Breeder Reactor-2 (EBR-2) is a sodium cooled power reactor supplying about 20 MWe to the Idaho National Engineering Laboratory (INEL) grid and, in addition, is the key component in the development of the Integral Fast Reactor (IFR). EBR-2's testing capability is extensive and has seen four major phases: (1) demonstration of LMFBR power plant feasibility, (2) irradiation testing for fuel and material development, (3) testing the off-normal performance of fuel and plant systems and (4) operation as the IFR prototype, developing and demonstrating the IFR technology associated with fuel and plant design. Specific programs being carried out in support of the IFR include advanced fuels and materials development, advanced control system development, plant diagnostics development and component testing. This paper discusses EBR-2 as the IFR prototype and the associated testing programs. 29 refs

REMOCIÓN DE ARSÉNICO (V ASISTIDA POR OXIDACIÓN UV SOLAR EN UN FOTO-REACTOR TUBULAR DE SECCIÓN CIRCULAR

Directory of Open Access Journals (Sweden)

Ramiro Escalera Vásquez

2010-01-01

Full Text Available Se ha construido y caracterizado un foto-reactor tubular de sección circular para su aplicación al tratamiento de aguas subterráneas contaminadas con Arsénico, As(V, utilizando las técnica de la Remoción de Arsénico por Oxidación Solar (RAOS. El concentrador solar que posee una capacidad de radiación equivalente a 2,8 soles, fue construido reciclando materiales desechados: tubos de vidrio proveniente de lámparas de Ne y tubos de desagüe sanitario de 6” (PVC, recubiertos por láminas de aluminio. Pruebas simultáneas sin agitación,realizadas aplicando la radiación UV solar a aguas sintéticas, demostraron que la remoción de As(V en el foto-reactor es más rápida queen un tubo de vidrio sólo y en una botella PET de 2 litros, logrando remociones mayores al 98% en todos los casos. Los tiempos para la aparición de los flóculos de complejo Fe-citrato fueron de 40, 50 y 90 min respectivamente, para intensidades de radiación UVA integral (290-390 nm entre 50 y 70 Wm-2. Pruebas de irradiación seguidas de agitación controlada a 30-33 s-1 de gradiente de velocidad, demostraron que el foto-reactor acelera el proceso de formación de flóculos fácilmente sedimentables al cabo de 20-30 min de agitación. Los tiempos de irradiación óptimos para el foto-reactor, el tubo y la botella son de 15, 25 y 60 min, respectivamente. Pruebas en régimen de flujo continuo en un foto-reactor de aproximadamente 1 m2 de área, con un tiempo de residencia hidráulica (igual al tiempo de irradiación de 15 min, mostraron la formación inmediata de flóculos fácilmente sedimentables cuando se agitan a 33 s-1 durante 20-30 min, lográndose una remoción del 98,36% una concentración remanente de 16,5 mgL-1 de As(V en aguas decantadas. Esto significa que se pueden tratar aproximadamente 130 Lm-2 en una jornada de 6 horas de radiación UVA de 50-70 Wm-2 de intensidad.

MLR reactor

International Nuclear Information System (INIS)

Ryazantsev, E.P.; Egorenkov, P.M.; Nasonov, V.A.; Smimov, A.M.; Taliev, A.V.; Gromov, B.F.; Kousin, V.V.; Lantsov, M.N.; Radchenko, V.P.; Sharapov, V.N.

1998-01-01

The Material Testing Loop Reactor (MLR) development was commenced in 1991 with the aim of updating and widening Russia's experimental base to validate the selected directions of further progress of the nuclear power industry in Russia and to enhance its reliability and safety. The MLR reactor is the pool-type one. As coolant it applies light water and as side reflector beryllium. The direction of water circulation in the core is upward. The core comprises 30 FA arranged as hexagonal lattice with the 90-95 mm pitch. The central materials channel and six loop channels are sited in the core. The reflector includes up to 11 loop channels. The reactor power is 100 MW. The average power density of the core is 0.4 MW/I (maximal value 1.0 MW/l). The maximum neutron flux density is 7.10 14 n/cm 2 s in the core (E>0.1 MeV), and 5.10 14 n/cm 2 s in the reflector (E<0.625 eV). In 1995 due to the lack of funding the MLR designing was suspended. (author)

ANSL-V: ENDF/B-V based multigroup cross-section libraries for Advanced Neutron Source (ANS) reactor studies. Supplement 1

Energy Technology Data Exchange (ETDEWEB)

Wright, R.Q.; Renier, J.P.; Bucholz, J.A.

1995-08-01

The original ANSL-V cross-section libraries (ORNL-6618) were developed over a period of several years for the physics analysis of the ANS reactor, with little thought toward including the materials commonly needed for shielding applications. Materials commonly used for shielding applications include calcium barium, sulfur, phosphorous, and bismuth. These materials, as well as {sup 6}Li, {sup 7}Li, and the naturally occurring isotopes of hafnium, have been added to the ANSL-V libraries. The gamma-ray production and gamma-ray interaction cross sections were completely regenerated for the ANSL-V 99n/44g library which did not exist previously. The MALOCS module was used to collapse the 99n/44g coupled library to the 39n/44g broad- group library. COMET was used to renormalize the two-dimensional (2- D) neutron matrix sums to agree with the one-dimensional (1-D) averaged values. The FRESH module was used to adjust the thermal scattering matrices on the 99n/44g and 39n/44g ANSL-V libraries. PERFUME was used to correct the original XLACS Legendre polynomial fits to produce acceptable distributions. The final ANSL-V 99n/44g and 39n/44g cross-section libraries were both checked by running RADE. The AIM module was used to convert the master cross-section libraries from binary coded decimal to binary format (or vice versa).

Sensing Traffic Density Combining V2V and V2I Wireless Communications

Directory of Open Access Journals (Sweden)

Julio A. Sanguesa

2015-12-01

Full Text Available Wireless technologies are making the development of new applications and services in vehicular environments possible since they enable mobile communication between vehicles (V2V, as well as communication between vehicles and infrastructure nodes (V2I. Usually, V2V communications are dedicated to the transmission of small messages mainly focused on improving traffic safety. Instead, V2I communications allow users to access the Internet and benefit from higher level applications. The combination of both V2V and V2I, known as V2X communications, can increase the benefits even further, thereby making intelligent transportation systems (ITS a reality. In this paper, we introduce V2X-d, a novel architecture specially designed to estimate traffic density on the road. In particular, V2X-d exploits the combination of V2V and V2I communications. Our approach is based on the information gathered by sensors (i.e., vehicles and road side units (RSUs and the characteristics of the roadmap topology to accurately make an estimation of the instant vehicle density. The combination of both mechanisms improves the accuracy and coverage area of the data gathered, while increasing the robustness and fault tolerance of the overall approach, e.g., using the information offered by V2V communications to provide additional density information in areas where RSUs are scarce or malfunctioning. By using our collaborative sensing scheme, future ITS solutions will be able to establish adequate dissemination protocols or to apply more efficient traffic congestion reduction policies, since they will be aware of the instantaneous density of vehicles.

Sensing Traffic Density Combining V2V and V2I Wireless Communications.

Science.gov (United States)

Sanguesa, Julio A; Barrachina, Javier; Fogue, Manuel; Garrido, Piedad; Martinez, Francisco J; Cano, Juan-Carlos; Calafate, Carlos T; Manzoni, Pietro

2015-12-16

Wireless technologies are making the development of new applications and services in vehicular environments possible since they enable mobile communication between vehicles (V2V), as well as communication between vehicles and infrastructure nodes (V2I). Usually, V2V communications are dedicated to the transmission of small messages mainly focused on improving traffic safety. Instead, V2I communications allow users to access the Internet and benefit from higher level applications. The combination of both V2V and V2I, known as V2X communications, can increase the benefits even further, thereby making intelligent transportation systems (ITS) a reality. In this paper, we introduce V2X-d, a novel architecture specially designed to estimate traffic density on the road. In particular, V2X-d exploits the combination of V2V and V2I communications. Our approach is based on the information gathered by sensors (i.e., vehicles and road side units (RSUs)) and the characteristics of the roadmap topology to accurately make an estimation of the instant vehicle density. The combination of both mechanisms improves the accuracy and coverage area of the data gathered, while increasing the robustness and fault tolerance of the overall approach, e.g., using the information offered by V2V communications to provide additional density information in areas where RSUs are scarce or malfunctioning. By using our collaborative sensing scheme, future ITS solutions will be able to establish adequate dissemination protocols or to apply more efficient traffic congestion reduction policies, since they will be aware of the instantaneous density of vehicles.

BR2 Reactor: Irradiation of fuels

International Nuclear Information System (INIS)

Verwimp, A.

2005-01-01

Safe, reliable and economical operation of reactor fuels, both UO 2 and MOX types, requires in-pile testing and qualification up to high target burn-up levels. In-pile testing of advanced fuels for improved performance is also mandatory. The objectives of research performed at SCK-CEN are to perform Neutron irradiation of LWR (Light Water Reactor) fuels in the BR2 reactor under relevant operating and monitoring conditions, as specified by the experimenter's requirements and to improve the on-line measurements on the fuel rods themselves

Efficient H2O2/CH3COOH oxidative desulfurization/denitrification of liquid fuels in sonochemical flow-reactors.

Science.gov (United States)

Calcio Gaudino, Emanuela; Carnaroglio, Diego; Boffa, Luisa; Cravotto, Giancarlo; Moreira, Elizabeth M; Nunes, Matheus A G; Dressler, Valderi L; Flores, Erico M M

2014-01-01

The oxidative desulfurization/denitrification of liquid fuels has been widely investigated as an alternative or complement to common catalytic hydrorefining. In this process, all oxidation reactions occur in the heterogeneous phase (the oil and the polar phase containing the oxidant) and therefore the optimization of mass and heat transfer is of crucial importance to enhancing the oxidation rate. This goal can be achieved by performing the reaction in suitable ultrasound (US) reactors. In fact, flow and loop US reactors stand out above classic batch US reactors thanks to their greater efficiency and flexibility as well as lower energy consumption. This paper describes an efficient sonochemical oxidation with H2O2/CH3COOH at flow rates ranging from 60 to 800 ml/min of both a model compound, dibenzotiophene (DBT), and of a mild hydro-treated diesel feedstock. Four different commercially available US loop reactors (single and multi-probe) were tested, two of which were developed in the authors' laboratory. Full DBT oxidation and efficient diesel feedstock desulfurization/denitrification were observed after the separation of the polar oxidized S/N-containing compounds (S≤5 ppmw, N≤1 ppmw). Our studies confirm that high-throughput US applications benefit greatly from flow-reactors. Copyright © 2013 Elsevier B.V. All rights reserved.

Volatility of V15Cr5Ti fusion reactor alloy

International Nuclear Information System (INIS)

Neilson, R.M. Jr.

1986-01-01

One potential hazard from the presence of activation products in fusion facilities is accidental oxidation-driven volatility of those activation products. Scoping experiments were conducted to investigate the oxidation and elemental volatility of candidate fusion reactor alloy V15Cr5Ti as a function of time, temperature, and test atmosphere. Experiments in air and in argon carrier gases containing 10 4 to 10 1 Pa (10 -1 to 10 -4 atm) oxygen were conducted to investigate the lower oxygen partial pressure limit for the formation of a low melting point (approximately 650 0 C), high volatility, oxide layer and its formation rate. Experiments to determine the elemental volatility of alloy constituents in air at temperatures of 700 0 C to greater than 1600 0 C. Some of these volatility experiments used V15Cr5Ti that was arc-remelted to incorporate small quantities (<0.1 wt. %) of Sc and Ca. Incorporation of Sc and Ca in test specimens permitted volatility measurement of radioactive constituents present only after activation of V15Cr5Ti

Ageing management of the BR2 research reactor

International Nuclear Information System (INIS)

Verpoortem, J. R.; Van Dyck, S.

2014-01-01

At the Belgian nuclear research centre (SCK.CEN) several test reactors are operated. Among these, Belgian Reactor 2 (BR2) is the largest Material Test Reactor (MTR). This water-cooled, beryllium moderated reactor with a maximum thermal power of 100 MW became operational in 1962. Except for two major refurbishment campaigns of one year each, this reactor has been operated continuously over the past 50 years, with a frequency of 5-12 cycles per year. At present, BR2 is used for different research activities, the production of medical isotopes, the production of n-doped silicon and various training and education activities. (Author)

Conceptual designs of power tokamak-type thermonuclear reactors

International Nuclear Information System (INIS)

Shejndlin, A.E.; Nedospasov, A.V.

1978-01-01

Physico-technical and ecological aspects of conceptual designing power tokamak-type reactors have been briefly considered. Only ''pure'' (''non-hybride'') reactors are discussed. Presented are main plasma-physical parameters, characteristics of blankets and magnetic systems of the following projects: PPPL; V-2; V-3; Culham-2, JAERI; TBEh-2500; TFTR. Two systems of the first wall protection have been considered: divertor one and by means of a layer of a cool turbulent plasma. Examined are the following problems: fuel loading, choice of the first wall material, blanket structure, magnetic system, environmental contamination. The comparison of relative hazards of fast neutron reactors and fusion reactors has shown that in respect of fusion reactors the biological hazard potential value is less by one-two orders

Damage by radiation in structural materials of BWR reactor vessels; Dano por radiacion en materiales estructurales de vasijas de reactores BWR

Energy Technology Data Exchange (ETDEWEB)

Robles, E.; Balcazar, M.; Alpizar, A.M.; Calderon, B.E. [Departamento de Sintesis y Caracterizacion de Materiales, Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

2002-07-01

The structural materials which are manufactured the pressure vessels of the BWR reactors undergo degradation in their mechanical properties mainly due to the damage produced by the fast neutrons (E> 1 MeV) coming from the reactor core. The mechanisms of neutron damage in this type of materials are experimentally studied, through the irradiation of vessel steel in experimental reactors for a quickly ageing. Alternately the neutron damage through steel irradiation with heavy ions is simulated. In this work the first results of the damage induced by irradiation of a similar steel to the vessel of a BWR reactor are shown. The irradiation was performed with fast neutrons (E> 1 MeV, fluence of 1.45 x 10{sup 18} n/cm{sup 2}) in the TRIGA Mark III Salazar reactor and separately with Ni{sup +3} ions in a Tandetrom accelerator (E= 4.8 MeV and an ion flux rank of 0.1 to 53 ions/A{sup 2}). (Author)

The 5th surveillance testing for Kori unit 2 reactor vessel materials

Energy Technology Data Exchange (ETDEWEB)

Chang, Kee Ok; Kim, Byoung Chul; Lee, Sam Lai; Choi, Kwon Jae; Gong, Un Sik; Chang, Jong Hwa; Joo, Yong Sun; Ahn, Sang Bok; Hong, Joon Hwa [Korea Atomic Energy Research Institute, Taejeon (Korea)

2001-03-01

Surveillance testing for reactor vessel materials is performed in order to evaluate the irradiation embrittlement due to neutrons during operation and set the condition of safe operation of nuclear reactor. The 5th surveillance testing was performed completely by Korea Atomic Energy Research Institute at Taejeon after the capsule was transported from Kori site including its removal from reactor. Fast neutron fluences for capsules were calculated and various testing including mechanical and chemistry analysis were performed in order to evaluate the integrity of Kori unit 2 reactor vessel during the operation until life time. The evaluation results are as follows; Fast neutron fluences for capsules V, R, P, T and N are 2.837E+18, 1.105E+19, 2.110E+19, 3.705E+19 and 4.831E+19n/cm{sup 2}, respectively. The bias factor, the ratio of measurement/calculation, was 0.918 for the 1st through 5th testing and the calculational uncertainty, 11.6% satisfied the requirement of USNRC Reg.Guide DG-1053, 20%. The best estimated neutron fluence for reactor vessel inside surface was 1.898E+19n/cm{sup 2} based on the end of 15th fuel cycle and it was predicted that the fluences of vessel inside surface at 32, 40, 48 and 56EFPY would reach 4.203E+19, 5.232E+19, 6.262E+19 and 7.291E+19n/cm{sup 2} based on the current calculation. The result through this analysis for Kori unit 2 showed that there would be no problem for the pressurized thermal shock(PTS) during the operation until design life. 49 refs., 35 figs., 48 tabs. (Author)

V-1 nuclear power plant standby RPP-16S computer software

International Nuclear Information System (INIS)

Suchy, R.

1988-01-01

The software structure of the function of program modules of the RPP-16S standby computer which is part of the information system of the V-1 Bohunice nuclear power plant are described. The multitasking AMOS operational system is used for the organization of programs in the computer. The program modules are classified in five groups by function, i.e., in modules for the periodical collection of values and for the measurement of process quantities for both nuclear power plant units; for the primary processing of the values; for the monitoring of exceedance of preset limits; for unit operators' communication with the computer. The fifth group consists of users program modules. The standby computer software was tested in the actual operating conditions of the V-1 power plant. The results showed it operated correctly; minor shortcomings were removed. (Z.M.). 1 fig

Minutes of the 2. Meeting of the WPRS / EGRPANS / Sodium Fast Reactor Task Force (SFR)

International Nuclear Information System (INIS)

Ivanov, Evgeny; Kereszturi, Andras; Pataki, I.; Tota, A.; Vertes, P.; Kim, Taek K.; Taiwo, T.A.; Kugo, Teruhiko; Lee, Yi Kang; Messaoudi, Nadia; Michel-Sendis, Franco; ); Pascal, Vincent; Buiron, Laurent; Varaine, Frederic; Ponomarev, Alexander

2012-01-01

Five organizations (SCK/CEN, KIT, KFKI, CEA, ANL) participated in the Sodium-cooled fast reactor (SFR) Benchmark calculations and all results were collected and compiled by CEA and ANL. The compiled results of the large size cores and medium size cores were presented by V. Pascal (CEA) and T. K. Kim (ANL), respectively. Separately, A. Kereszturi presented his recently updated results. It was observed that there is wide variation in core multiplication factor, kinetics parameters, and reactivity feedback coefficients. In particular, compared to the CEA results, ANL calculated smaller k-eff, Doppler constant, but higher sodium void worth and control rod worth. The core modeling issue (heterogeneous vs. homogeneous) and solution method (diffusion vs. transport) were identified as the potential reasons of these discrepancies, including the minor impacts from the depletion chains and lumped fission product modeling. All participants agreed that additional investigation was needed to identify the reasons of these discrepancies. In addition, V. Pascal presented the informative notes of the reactivity feedback calculations methodology proposed by CEA. This document brings together the 5 presentations (slides) given at this meeting: 1 - SFR Task Force : Core behavior during transient as a function of power size and fuel nature (L. Buiron, V. Pascal, F. Varaine); 2 - Sodium Fast Reactor core Feedback and Transient response (SFRFT) Expert Group: preliminary benchmark results for large cores (L. Buiron, V. Pascal, F. Varaine); 3 - Numerical Benchmark Results for 1000 MWth Sodium-cooled Fast Reactor (T.K. Kim and T.A. Taiwo); 4 - Preliminary results of the WPRS Sodium-Cooled Fast Reactor Benchmark problems (A. Kereszturi, I. Pataki, A. Tota, P. Vertes); 5 - SFR Task Force : proposal for Feedback coefficients estimation methodology (L. Buiron, V.Pascal, F. Varaine)

Calculation of low-energy reactor neutrino spectra reactor for reactor neutrino experiments

Energy Technology Data Exchange (ETDEWEB)

Riyana, Eka Sapta; Suda, Shoya; Ishibashi, Kenji; Matsuura, Hideaki [Dept. of Applied Quantum Physics and Nuclear Engineering, Kyushu University, Kyushu (Japan); Katakura, Junichi [Dept. of Nuclear System Safety Engineering, Nagaoka University of Technology, Nagaoka (Japan)

2016-06-15

Nuclear reactors produce a great number of antielectron neutrinos mainly from beta-decay chains of fission products. Such neutrinos have energies mostly in MeV range. We are interested in neutrinos in a region of keV, since they may take part in special weak interactions. We calculate reactor antineutrino spectra especially in the low energy region. In this work we present neutrino spectrum from a typical pressurized water reactor (PWR) reactor core. To calculate neutrino spectra, we need information about all generated nuclides that emit neutrinos. They are mainly fission fragments, reaction products and trans-uranium nuclides that undergo negative beta decay. Information in relation to trans-uranium nuclide compositions and its evolution in time (burn-up process) were provided by a reactor code MVP-BURN. We used typical PWR parameter input for MVP-BURN code and assumed the reactor to be operated continuously for 1 year (12 months) in a steady thermal power (3.4 GWth). The PWR has three fuel compositions of 2.0, 3.5 and 4.1 wt% {sup 235}U contents. For preliminary calculation we adopted a standard burn-up chain model provided by MVP-BURN. The chain model treated 21 heavy nuclides and 50 fission products. The MVB-BURN code utilized JENDL 3.3 as nuclear data library. We confirm that the antielectron neutrino flux in the low energy region increases with burn-up of nuclear fuel. The antielectron-neutrino spectrum in low energy region is influenced by beta emitter nuclides with low Q value in beta decay (e.g. {sup 241}Pu) which is influenced by burp-up level: Low energy antielectron-neutrino spectra or emission rates increase when beta emitters with low Q value in beta decay accumulate. Our result shows the flux of low energy reactor neutrinos increases with burn-up of nuclear fuel.

Reactor theory and power reactors. 1. Calculational methods for reactors. 2. Reactor kinetics

International Nuclear Information System (INIS)

Henry, A.F.

1980-01-01

Various methods for calculation of neutron flux in power reactors are discussed. Some mathematical models used to describe transients in nuclear reactors and techniques for the reactor kinetics' relevant equations solution are also presented

Investigation of tritium and 233U breeding in a fission-fusion hybrid reactor fuelling with ThO2

International Nuclear Information System (INIS)

Yildiz, K.; Sahin, S.; Sahin, H. M.; Acir, A.; Yalcin, S.; Altinok, T.; Bayrak, M.; Alkan, M.; Durukan, O.

2007-01-01

In the world, thorium reserves are three times more than natural Uranium reserves. It is planned in the near future that nuclear reactors will use thorium as a fuel. Thorium is not a fissile isotope because it doesn't make fission with thermal neutrons so it could be converted to 2 33U isotope which has very high quality fission cross-section with thermal neutrons. 2 33U isotope can be used in present LWRs as an enrichment fuel. In the fusion reactors, tritium is the most important fossil fuel. Because tritium is not natural isotope, it has to be produced in the reactor. The purpose of this work is to investigate the tritium and 2 33U breeding in a fission-fusion hybrid reactor fuelling with ThO 2 for Δt=10 days during a reactor operation period in five years. The neutronic analysis is performed on an experimental hybrid blanket geometry. In the center of the hybrid blanket, there is a line neutron source in a cylindrical cavity, which simulates the fusion plasma chamber where high energy neutrons (14.1 MeV) are produced. The conventional fusion reaction delivers the external neutron source for blankets following, 2 D + 3 T →? 4 He (3.5 MeV) + n (14.1 MeV). (1) The fuel zone made up of natural-ThO 2 fuel and it is cooled with different coolants. In this work, five different moderator materials, which are Li 2 BeF 4 , LiF-NaF-BeF 2 , Li 2 0Sn 8 0, natural Lithium and Li 1 7Pb 8 3, are used as coolants. The radial reflector, called tritium breeding zones, is made of different Lithium compounds and graphite in sandwich structure. In the work, eight different Lithium compounds were used as tritium breeders in the tritium breeding zones, which are Li 3 N, Li 2 O, Li 2 O 2 , Li 2 TiO 3 , Li 4 SiO 3 , Li 2 ZrO 3 , LiBr and LiH. Neutron transport calculations are conducted in spherical geometry with the help of SCALE4.4A SYSTEM by solving the Boltzmann transport equation with code CSAS and XSDRNPM, under consideration of unresolved and resolved resonances, in S 8 -P 3

Studies of fragileness in steels of vessels of BWR reactors; Estudios de fragilizacion en aceros de vasija de reactores BWR

Energy Technology Data Exchange (ETDEWEB)

Robles, E.F.; Balcazar, M.; Alpizar, A.M.; Calderon, B.E. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

2003-07-01

The structural materials with those that are manufactured the pressure vessels of the BWR reactors, suffer degradation in its mechanical properties mainly to the damage taken place by the fast neutrons (E > 1 MeV) coming from the reactor core. Its are experimentally studied those mechanisms of neutron damage in this material type, by means of the irradiation of steel vessel in experimental reactors to age them quickly. Alternatively it is simulated the neutron damage by means of irradiation of steel with heavy ions. In this work those are shown first results of the damage induced by irradiation from a similar steel to the vessel of a BWR reactor. The irradiation was carried out with fast neutrons (E > 1 MeV, fluence of 1.45 x 10{sup 18} n/cm{sup 2}) in the TRIGA MARK lll reactor and separately with Ni{sup +3} ions in a Tandetrom accelerator, E = 4.8 MeV and range of the ionic flow of 0.1 to 53 iones/A{sup 2}. (Author)

Development of 'low activation superconducting wire' for an advanced fusion reactor

International Nuclear Information System (INIS)

Hishinuma, Y.; Yamada, S.; Sagara, A.; Kikuchi, A.; Takeuchi, T.; Matsuda, K.; Taniguchi, H.

2011-01-01

In the D-T burning plasma reactor beyond ITER such as DEMO and fusion power plants assuming the steady-state and long time operation, it will be necessary to consider carefully induced radioactivity and neutron irradiation properties on the all components for fusion reactors. The decay time of the induced radioactivity can control the schedule and scenarios of the maintenance and shutdown on the fusion reactor. V 3 Ga and MgB 2 compound have shorter decay time within 1 years and they will be desirable as a candidate material to realize 'low activation and high magnetic field superconducting magnet' for advanced fusion reactor. However, it is well known that J c -B properties of V 3 Ga and MgB 2 wires are lower than that of the Nb-based A15 compound wires, so the J c -B enhancements on the V 3 Ga and MgB 2 wires are required in order to apply for an advanced fusion reactor. We approached and succeeded to developing the new process in order to improve J c properties of V 3 Ga and MgB 2 wires. In this paper, the recent activities for the J c improvements and detailed new process in V 3 Ga and MgB 2 wires are investigated. (author)

Decommissioning and radioactive waste management. The European Commission overview

International Nuclear Information System (INIS)

Rehak, M

2010-01-01

In this lecture author deals with the European Commission overview on the decommissioning and radioactive waste management. Financial support of European Commission of decommissioning of the Ignalina NPP, Bohunice V1 NPP and Kozloduy Units 1 and 2 is presented.

BR2 reactor neutron beams

International Nuclear Information System (INIS)

Neve de Mevergnies, M.

1977-01-01

The use of reactor neutron beams is becoming increasingly more widespread for the study of some properties of condensed matter. It is mainly due to the unique properties of the ''thermal'' neutrons as regards wavelength, energy, magnetic moment and overall favorable ratio of scattering to absorption cross-sections. Besides these fundamental reasons, the impetus for using neutrons is also due to the existence of powerful research reactors (such as BR2) built mainly for nuclear engineering programs, but where a number of intense neutron beams are available at marginal cost. A brief introduction to the production of suitable neutron beams from a reactor is given. (author)

Visible-Light-Responsive Photocatalysis: Ag-Doped TiO2 Catalyst Development and Reactor Design Testing

Science.gov (United States)

Coutts, Janelle L.; Hintze, Paul E.; Meier, Anne; Shah, Malay G.; Devor, Robert W.; Surma, Jan M.; Maloney, Phillip R.; Bauer, Brint M.; Mazyck, David W.

2016-01-01

In recent years, the alteration of titanium dioxide to become visible-light-responsive (VLR) has been a major focus in the field of photocatalysis. Currently, bare titanium dioxide requires ultraviolet light for activation due to its band gap energy of 3.2 eV. Hg-vapor fluorescent light sources are used in photocatalytic oxidation (PCO) reactors to provide adequate levels of ultraviolet light for catalyst activation; these mercury-containing lamps, however, hinder the use of this PCO technology in a spaceflight environment due to concerns over crew Hg exposure. VLR-TiO2 would allow for use of ambient visible solar radiation or highly efficient visible wavelength LEDs, both of which would make PCO approaches more efficient, flexible, economical, and safe. Over the past three years, Kennedy Space Center has developed a VLR Ag-doped TiO2 catalyst with a band gap of 2.72 eV and promising photocatalytic activity. Catalyst immobilization techniques, including incorporation of the catalyst into a sorbent material, were examined. Extensive modeling of a reactor test bed mimicking air duct work with throughput similar to that seen on the International Space Station was completed to determine optimal reactor design. A bench-scale reactor with the novel catalyst and high-efficiency blue LEDs was challenged with several common volatile organic compounds (VOCs) found in ISS cabin air to evaluate the system's ability to perform high-throughput trace contaminant removal. The ultimate goal for this testing was to determine if the unit would be useful in pre-heat exchanger operations to lessen condensed VOCs in recovered water thus lowering the burden of VOC removal for water purification systems.

Fission product release from SLOWPOKE-2 reactors

Energy Technology Data Exchange (ETDEWEB)

Harnden-Gillis, A M.C. [Queen` s Univ., Kingston, ON (Canada). Dept. of Physics

1994-12-31

Increasing radiation fields at several SLOWPOKE-2 reactors fuelled with highly enriched uranium aluminum alloy fuel have begun to interfere with the daily operation of these reactors. To investigate this phenomenon, samples of reactor container water and gas from the headspace were obtained at four SLOWPOKE-2 reactor facilities and examined by gamma ray spectroscopy methods. These radiation fields are due to the circulation of fission products within the reactor container vessel. The most likely source of the fission product release is an area of uranium-bearing material exposed to the coolant at the end weld line which originated at the time of fuel fabrication. The results of this study are compared with observations from an underwater visual examination of one core and the metallographic examination of archived fuel elements. 19 refs., 4 tabs., 8 figs.

Phase diagrams of systems of Sr2V2O7-M2V2O7 and of Ba2V2O7-M2V2O7 (M=Ca,Cd)

International Nuclear Information System (INIS)

Fotiev, A.A.; Zhuravlev, V.D.; Zhukov, V.P.

1982-01-01

Using the methods of X-ray phase and differential thermal anlyses phase equilibria in the systems Sr 2 V 2 O 7 -M 2 V 2 O 7 and Ba 2 V 2 O 7 -M 2 V 2 O 7 , where M--Ca, Cd, are studied, their phase diagrams being built. New double pyrovanadates Mosub(0.5)Srsub(1.5)Vsub(2)Osub(7) and MBaV 2 O 7 are found [ru

Pressurized water reactor simulator. Workshop material. 2. ed

International Nuclear Information System (INIS)

2005-01-01

The International Atomic Energy Agency (IAEA) has established an activity in nuclear reactor simulation computer programs to assist its Member States in education. The objective is to provide, for a variety of advanced reactor types, insight and practice in their operational characteristics and their response to perturbations and accident situations. To achieve this, the IAEA arranges for the development and distribution of simulation programs and educational material and sponsors courses and workshops. The workshops are in two parts: techniques and tools for reactor simulator development. And the use of reactor simulators in education. Workshop material for the first part is covered in the IAEA Training Course Series No. 12, 'Reactor Simulator Development' (2001). Course material for workshops using a WWER- 1000 reactor department simulator from the Moscow Engineering and Physics Institute, the Russian Federation is presented in the IAEA Training Course Series No. 21, 2nd edition, 'WWER-1000 Reactor Simulator' (2005). Course material for workshops using a boiling water reactor simulator developed for the IAEA by Cassiopeia Technologies Incorporated of Canada (CTI) is presented in the IAEA publication: Training Course Series No.23, 2nd edition, 'Boiling Water Reactor Simulator' (2005). This report consists of course material for workshops using a pressurized water reactor simulator

Assessment of capability for modeling the core degradation in 2D geometry with ASTEC V2 integral code for VVER type of reactor

International Nuclear Information System (INIS)

Dimov, D.

2011-01-01

The ASTEC code is progressively becoming the reference European severe accident integral code through in particular the intensification of research activities carried out since 2004. The purpose of this analysis is to assess ASTEC code modelling of main phenomena arising during hypothetical severe accidents and particularly in-vessel degradation in 2D geometry. The investigation covers both early and late phase of degradation of reactor core as well as determination of corium which will enter the reactor cavity. The initial event is station back-out. In order to receive severe accident condition, failure of all active component of emergency core cooling system is apply. The analysis is focus on ICARE module of ASTEC code and particularly on so call MAGMA model. The aim of study is to determine the capability of the integral code to simulate core degradation and to determine the corium composition entering the reactor cavity. (author)

Measurements of the total neutron cross-sections of U and UO2 below 2 eV at different temperatures

International Nuclear Information System (INIS)

Adib, M.; Maayouf, R.M.A.; Abdel-Kawy, A.; Ashry, A.; Abbas, Y.; Abu-Zahra, A.; Hamouda, I.

1982-11-01

The total neutron cross-sections of natural uranium and its oxide are measured using two time of flight spectrometers, installed in front of two of the ET-RR-1 reactor horizontal channels, and also by a neutron diffraction spectrometer. The measurements were carried out at room temperature in the energy range from 2 eV-0.002 eV and at 210 deg. C, for neutron energies below 0.005 eV. The coherent scattering cross-section of U was deduced both from the Bragg cut-offs observed in the behaviour of the total neutron cross-section of both U and UO 2 at cold neutron energies and the neutron diffraction pattern obtained at room temperature. (author)

Evaluation of VVER-1200/V-491 reactor pressure vessel integrity during large break LOCA along with SBO using MELCOR 1.8.6

International Nuclear Information System (INIS)

Bui Thi Hoa; Tran Chi Thanh

2015-01-01

After Fukushima accident and stress test recommended by IAEA for existing reactors, higher safety requirements are enforced upon nuclear power plants during design extension and severe accident conditions. Based on those arguments, Vietnam Government requests a lot of effective safety solutions, in designs proposed for the nuclear power plants in Ninh Thuan province of Vietnam, which can prevent the accident progression toward severe accidents and mitigate severe accident consequences. One of safety requirements is related to delay time of core melt during design extension condition. Especially, if the worst case of accidents occurs, the reactor vessel integrity must be maintained at least 24 hours from the beginning of the accident. With the aim at investigation of Reactor Pressure Vessel (RPV) integrity, in this study, MELCOR 1.8.6 code is used to evaluate the integrity of RPV lower head for VVER-1200/V-491 reactor during a Large Break Loss of Coolant Accident (LBLOCA) in combination with Station Blackout (SBO) event. The study figures out several parameters related to melt down progress such as: rupture position and rupture timing, the amount of hydrogen generated. Availability of the second stage hydro-accumulators (HA2) in the VVER-1200/V-491 is assumed as an additional improvement to delay the timing of core melt as well as to maintain the vessel integrity for long-term. (author)

Damage by radiation in structural materials of BWR reactor vessels

International Nuclear Information System (INIS)

Robles, E.; Balcazar, M.; Alpizar, A.M.; Calderon, B.E.

2002-01-01

The structural materials which are manufactured the pressure vessels of the BWR reactors undergo degradation in their mechanical properties mainly due to the damage produced by the fast neutrons (E> 1 MeV) coming from the reactor core. The mechanisms of neutron damage in this type of materials are experimentally studied, through the irradiation of vessel steel in experimental reactors for a quickly ageing. Alternately the neutron damage through steel irradiation with heavy ions is simulated. In this work the first results of the damage induced by irradiation of a similar steel to the vessel of a BWR reactor are shown. The irradiation was performed with fast neutrons (E> 1 MeV, fluence of 1.45 x 10 18 n/cm 2 ) in the TRIGA Mark III Salazar reactor and separately with Ni +3 ions in a Tandetrom accelerator (E= 4.8 MeV and an ion flux rank of 0.1 to 53 ions/A 2 ). (Author)

Studies of fragileness in steels of vessels of BWR reactors

International Nuclear Information System (INIS)

Robles, E.F.; Balcazar, M.; Alpizar, A.M.; Calderon, B.E.

2003-01-01

The structural materials with those that are manufactured the pressure vessels of the BWR reactors, suffer degradation in its mechanical properties mainly to the damage taken place by the fast neutrons (E > 1 MeV) coming from the reactor core. Its are experimentally studied those mechanisms of neutron damage in this material type, by means of the irradiation of steel vessel in experimental reactors to age them quickly. Alternatively it is simulated the neutron damage by means of irradiation of steel with heavy ions. In this work those are shown first results of the damage induced by irradiation from a similar steel to the vessel of a BWR reactor. The irradiation was carried out with fast neutrons (E > 1 MeV, fluence of 1.45 x 10 18 n/cm 2 ) in the TRIGA MARK lll reactor and separately with Ni +3 ions in a Tandetrom accelerator, E = 4.8 MeV and range of the ionic flow of 0.1 to 53 iones/A 2 . (Author)

Radiological characterisation on V1 NPP technological systems and buildings - Contamination

International Nuclear Information System (INIS)

Hanzel, Richard; Rapant, Tibor; Svitek, Jaroslav

2012-01-01

Since 2001, the preparation of V1 NPP practical decommissioning has been supported and partly financed by the Bohunice International Decommissioning Support Fund, under the administration of the European bank for Reconstruction and development. AMEC Nuclear Slovakia, together with partners STM Power and EWN GmbH, performed BIDSF B.4 project - Decommissioning database development. The main purpose of the B6.4 project was to develop a comprehensive physical and radiological inventory database to support RAW management development of the decommissioning studies and decommissioning project of Bohunice V1 NPP. AMEC Nuclear Slovakia was responsible mainly for DDB design, planning documents and physical and radiological characterization including sampling and analyses of the plant controlled area. The objective of V1 NPP radiological characterization was summarisation of sampling and analyses results, description of methodology used for radiological characterization and determination of the V1 NPP radiological inventory. Results of the characterization survey included the identification and distribution of contamination in buildings, structures, and other site facilities or other impacted media. The characterization survey clearly identified those portions of the site that have been affected by site activities and are contaminated. The survey also identified the portions of the site that have not been affected by these activities and can be marked as 'not impacted'. Radiological data have been presented also on the basis of index RAI level, where 5 radiological classes have been defined. On the basis of sampling and analyses results following radiological parameters have been assigned to all impacted components and civil structures included in DDB: dose rate in contact, dose rate in distance 1 m, external surface contamination, internal surface contamination and volume/mass contamination. Each room in controlled area has been described by following radiological parameters

Advances in Reactor Physics, Mathematics and Computation. Volume 2

Energy Technology Data Exchange (ETDEWEB)

1987-01-01

These proceedings of the international topical meeting on advances in reactor physics, mathematics and computation, Volume 2, are divided into 7 sessions bearing on: - session 7: Deterministic transport methods 1 (7 conferences), - session 8: Interpretation and analysis of reactor instrumentation (6 conferences), - session 9: High speed computing applied to reactor operations (5 conferences), - session 10: Diffusion theory and kinetics (7 conferences), - session 11: Fast reactor design, validation and operating experience (8 conferences), - session 12: Deterministic transport methods 2 (7 conferences), - session 13: Application of expert systems to physical aspects of reactor design and operation.

Analytical and experimental verification of confinement upgrading for Bohunice NPP V1

International Nuclear Information System (INIS)

Tkac, A.

2000-01-01

The scope of this paper is to provide a brief description of confinement improvement for NPP V-1 and supporting thermal-hydraulic analyses and experimental results. Series of analyses are performed in the process of the designing of an improved confinement system. Based on the analytical results obtained in the PHARE Project NS01/91 'Confinement and Improved ECCS Evaluation' as well as on additional activities performed after its finishing, additional modifications have been proposed during the designing. It is required to minimize the construction works EWST ceiling, while final solution shall fulfil acceptance criteria set forth in Decision 1/94 of Slovak Regulatory Authority (UJD). The technical requirement of the UJD is related to confinement. IAEA recommendations are taken into account. Due to new definitions of DBA and BDBA first considerations were connected and oriented on possible value of pressure peak increasing. As a result of the structural analysis limiting values for hermetic zone are determined. Some design modifications of the hermetic zone are proposed

CATHARE 2 V2.5 : a fully validated CATHARE version for various applications

International Nuclear Information System (INIS)

Robert, M.; Farvacque, M.; Parent, M.; Faydide, B.

2003-01-01

The CATHARE code is devoted to best estimate calculations of thermal-hydraulic transients in nuclear reactors. The code is based on a 2-fluid 6-equation model including non-condensable gases equations and additional equations for radio-chemical components transport. It allows the coolant circuits of any reactor to be represented by assembling 1D, 0D and 3D modules. The outcome of more than 20 years of joint development effort by CEA, EDF, FRAMATOME-ANP and IRSN, is the CATHARE 2 V2.5 version, to be released at the end of 2003. The development strategy of this version was to include in one single version the functionalities and the models needed for all the various applications the CATHARE partners have to deal with, in the scope of thermal-hydraulic nuclear safety analysis. Physical assessment is a highly time consuming activity for this kind of code. The 'single version' strategy results in putting together the validation efforts required for each application, thus significantly reducing the global validation effort. It also makes the maintenance process more efficient. The main objective of CATHARE 2 V2.5 is to perform safety analyses for Pressurized Water Reactors postulated accidents or other incidents, such as primary LOCAs, SGTR, loss of RHR, secondary breaks, loss of feed-water, etc. The 3D module of CATHARE has been developed in connection with the future safety methodologies based on the 3D modelling of the vessel. The main application is the large break LOCA where significant 3D effects take place, and in particular the phenomena related to the core radial temperature profile, the 3D core quenching pattern, the bypass of the accumulator water to the break and CCFL phenomena in the down-comer during the refill phase. These effects are exemplified with a PWR large break LOCA calculation using a 3D modeling of the vessel. Another major application of this version of CATHARE is to be used without modification in the SIPA French reactor simulator. This

Nuclear materials

International Nuclear Information System (INIS)

1996-01-01

In 1998, Nuclear Regulatory Authority of the Slovak Republic (NRA SR) performed 38 inspections, 25 of them were performed in co-operation with IAEA inspectors. There is no fresh nuclear fuel at Bohunice A-1 NPP at present. Fresh fuel of Bohunice V-1 and V-2 NPPs is inspected in the fresh fuel storage.There are 327 fresh fuel assemblies in Mochovce NPP fresh fuel storage. In addition to that, are also 71 small users of nuclear materials in Slovakia. In most cases they use: covers made of depleted uranium for non-destructive works, detection of level in production plants, covers for therapeutical sources at medical facilities. In. 1995, NRA SR issued 4 new licences for nuclear material withdrawal. In the next part manipulation with nuclear materials, spent fuel stores and illegal trafficking in nuclear materials are reported

Research reactor core conversion guidebook. V.1: Summary

International Nuclear Information System (INIS)

1992-04-01

In view of the proliferation concerns caused by the use of highly enriched uranium (HEU) and in anticipation that the supply of HEU to research and test reactors will be more restricted in the future, this guidebook has been prepared to assist research reactor operators in addressing the safety and licensing issues for conversion of their reactor cores from the use of HEU fuel to the use of low enriched uranium fuel. This Guidebook, in five volumes, addresses the effects of changes in the safety-related parameters of mixed cores and the converted core. It provides an information base which should enable the appropriate approvals processes for implementation of a specific conversion proposal, whether for a light or for a heavy water moderated research reactor. Refs, figs, bibliographies and tabs

Calculation of criticality of the AP600 reactor with KENO V.a code

Energy Technology Data Exchange (ETDEWEB)

Krumbein, A; Caner, M; Shapira, M [Israel Atomic Energy Commission, Yavne (Israel). Soreq Nuclear Research Center

1996-12-01

The Westinghouse AP600 PWR has been modeled using the KENO V.a three dimensional Monte Carlo criticality program of the SCALE-PC code system. These calculations and the use of a Monte Carlo neutron transport code such as KENO will provide us with an independent check on our WIMS/CITATION calculations for the AP600 as well as for other reactors. It will also enable us to model more complicated geometries. (authors).

Neutron transport. Physics and calculation of nuclear reactors with applications to pressurized water reactors and fast neutron reactors. 2 ed.

International Nuclear Information System (INIS)

Bussac, J.; Reuss, P.

1985-01-01

This book presents the main physical bases of neutron theory and nuclear reactor calculation. 1) Interactions of neutrons with matter and basic principles of neutron transport; 2) Neutron transport in homogeneous medium and the neutron field: kinetic behaviour, slowing-down, resonance absorption, diffusion equation, processing methods; 3) Theory of a reactor constituted with homogeneous zones: critical condition, kinetics, separation of variables, calculation and neutron balance of the fundamental mode, one-group and multigroup theories; 4) Study of heterogeneous cell lattices: fast fission factor, resonance absorption, thermal output factor, diffusion coefficient, computer codes; 5) Operation and control of reactors: perturbation theory, reactivity, fuel properties evolution, poisoning by fission products, calculation of a reactor and fuel management; 6) Study of some types of reactors: PWR and fast breeder reactors, the main reactor types of the present French program [fr

In-service inspections of V-230 reactor

International Nuclear Information System (INIS)

Prepechal, J.

1984-01-01

It is stated that despite certain constraints the configuration of the WWER-440 is such that it allows to make in-service inspections on a fully satisfactory scale. Three factors are discussed whose existence is necessary for the implementation of in-service inspections. The program defining the scale of inspections is satisfactory with regard to the safety and reliability of reactor operation. Its further development must result in reducing time consumption and radiation burden of personnel. Regulations for the implementation and evaluation of inspections represent the weakest link in the system of in-service inspections. At present, various organizations are dealing with the said problem within international cooperation. Equipment for in-service inspections of WWER-440 reactors is relatively good. The most important knowledge is summed up gained from the ten pre-service and in-service inspections of reactors of this type made so far. (Z.M.)

TPDWR2: thermal power determination for Westinghouse reactors, Version 2. User's guide

International Nuclear Information System (INIS)

Kaczynski, G.M.; Woodruff, R.W.

1985-12-01

TPDWR2 is a computer program which was developed to determine the amount of thermal power generated by any Westinghouse nuclear power plant. From system conditions, TPDWR2 calculates enthalpies of water and steam and the power transferred to or from various components in the reactor coolant system and to or from the chemical and volume control system. From these results and assuming that the reactor core is operating at constant power and is at thermal equilibrium, TPDWR2 calculates the thermal power generated by the reactor core. TPDWR2 runs on the IBM PC and XT computers when IBM Personal Computer DOS, Version 2.00 or 2.10, and IBM Personal Computer Basic, Version D2.00 or D2.10, are stored on the same diskette with TPDWR2

Once-through CANDU reactor models for the ORIGEN2 computer code

International Nuclear Information System (INIS)

Croff, A.G.; Bjerke, M.A.

1980-11-01

Reactor physics calculations have led to the development of two CANDU reactor models for the ORIGEN2 computer code. The model CANDUs are based on (1) the existing once-through fuel cycle with feed comprised of natural uranium and (2) a projected slightly enriched (1.2 wt % 235 U) fuel cycle. The reactor models are based on cross sections taken directly from the reactor physics codes. Descriptions of the reactor models, as well as values for the ORIGEN2 flux parameters THERM, RES, and FAST, are given

SCORPIO-VVER core monitoring and surveillance system with advanced capabilities

International Nuclear Information System (INIS)

Molnar, J.; Vocka, R.

2010-01-01

In this work authors present 12 years of operation experience of core monitoring and surveillance system with advanced capabilities on nuclear power plants on 6 unit of VVER-440 type of reactors at two different NPPs. The original version of the SCORPIO (Surveillance of reactor CORe by PIcture On-line display) system was developed for the western type of PWR reactors. The first version of the SCORPIO-VVER Core Monitoring System for Dukovany NPP (VVER-440 type of reactor, Czech Republic) was developed in 1998. For SCORPIO-VVER implementation at Bohunice NPP in Slovakia (2001) the system was enhanced with startup module KRITEX.

Radiation protection at the RA Reactor in 1988, Part -2, RA reactor annual report

International Nuclear Information System (INIS)

Ninkovic, M.; Ajdacic, N.; Zaric, M.; Vukovic, Z.

1988-01-01

Radiation protection tasks which enable safe operation of the RA reactor, and are defined according the the legal regulations and IAEA safety recommendations are sorted into four categories in this report: (1) Control of the working environment, dosimetry at the RA reactor and radiation protection; (2) Radioactivity control in the vicinity of the reactor and meteorology measurements; (3) Decontamination and relevant actions, collecting and treatment of fluid effluents; and and solid radioactive wastes [sr

Irradiation effects on Zr-2.5Nb in power reactors

Energy Technology Data Exchange (ETDEWEB)

Song, C., E-mail: Carol.Song@cnl.ca [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada)

2016-06-15

Zirconium alloys are widely used as structural materials in nuclear applications because of their attractive properties such as a low absorption cross-section for thermal neutrons, excellent corrosion resistance in water, and good mechanical properties at reactor operating temperatures. Zr-2.5Nb is one of the most commonly used zirconium alloys and has been used for pressure tube materials in CANDU (Canada Deuterium Uranium) and RBMK (Reaktor Bolshoy Moshchnosti Kanalnyy, 'High Power Channel-type Reactor') reactors for over 40 years. In a recent report from the Electric Power Research Institute, Zr-2.5Nb was identified as one of the candidate materials for use in normal structural applications in light-water reactors owing to its increased resistance to irradiation-induced degradation as compared with currently used materials. Historically, the largest program of in-reactor tests on zirconium alloys was performed by Atomic Energy of Canada Limited. Over many years of in-reactor testing and CANDU operating experience with Zr- 2.5Nb, extensive research has been conducted on the irradiation effects on its microstructures, mechanical properties, deformation behaviours, fracture toughness, delayed hydride cracking, and corrosion. Most of the results on Zr-2.5Nb obtained from CANDU experience could be used to predict the material performance under light water reactors. This paper reviews the irradiation effects on Zr-2.5Nb in power reactors (including heavy-water and light-water reactors) and summarizes the current state of knowledge. (author)

Enhancements to the SLOWPOKE-2 nuclear research reactor at the Royal Military College of Canada

Energy Technology Data Exchange (ETDEWEB)

Hungler, P.C.; Andrews, M.T.; Weir, R.D.; Nielson, K.S.; Chan, P.K.; Bennett, L.G.I., E-mail: paul.hungler@rmc.ca [Royal Military College of Canada, Kingston, Ontario (Canada)

2014-07-01

In 1985 a Safe Low Power C(K)ritical Experiment (SLOWPOKE) nuclear research reactor was installed at the Royal Military College of Canada (RMCC). The reactor at nominally 20 kW thermal was named SLOWPOKE-2 and the core was designed to have a total of 198 fuel pins with Low Enriched Uranium (LEU) fuel (19.89% U-235). Installation of the reactor was intended to provide an education tool for members of the Canadian Armed Forces (CAF) and an affordable neutron source for the application of neutron activation analysis (NAA) and radioisotope production. Today, the SLOWPOKE-2 at RMCC continues to be a key education tool for undergraduate and post-graduate students and successfully conducts NAA and isotope production as per its original design intent. RMCC has significantly upgraded the facility and instruments to develop capabilities such as delayed neutron and gamma counting (DNGC) and neutron imaging, including 2D thermal neutron radiography and 3D thermal neutron tomography. These unique nuclear capabilities have been applied to relevant issues in the CAF. The analog control system originally installed in 1985 has been removed and replaced in 2001 by the SLOWPOKE Integrated Reactor Control and Instrumentation System (SIRCIS) which is a digital controller. This control system continues to evolve with SIRCIS V2 currently in operation. The continual enhancement of the facility, instruments and systems at the SLOWPOKE-2 at RMCC will be discussed, including an update on RMCC's refueling plan. (author)

Enhancements to the SLOWPOKE-2 nuclear research reactor at the Royal Military College of Canada

International Nuclear Information System (INIS)

Hungler, P.C.; Andrews, M.T.; Weir, R.D.; Nielson, K.S.; Chan, P.K.; Bennett, L.G.I.

2014-01-01

In 1985 a Safe Low Power C(K)ritical Experiment (SLOWPOKE) nuclear research reactor was installed at the Royal Military College of Canada (RMCC). The reactor at nominally 20 kW thermal was named SLOWPOKE-2 and the core was designed to have a total of 198 fuel pins with Low Enriched Uranium (LEU) fuel (19.89% U-235). Installation of the reactor was intended to provide an education tool for members of the Canadian Armed Forces (CAF) and an affordable neutron source for the application of neutron activation analysis (NAA) and radioisotope production. Today, the SLOWPOKE-2 at RMCC continues to be a key education tool for undergraduate and post-graduate students and successfully conducts NAA and isotope production as per its original design intent. RMCC has significantly upgraded the facility and instruments to develop capabilities such as delayed neutron and gamma counting (DNGC) and neutron imaging, including 2D thermal neutron radiography and 3D thermal neutron tomography. These unique nuclear capabilities have been applied to relevant issues in the CAF. The analog control system originally installed in 1985 has been removed and replaced in 2001 by the SLOWPOKE Integrated Reactor Control and Instrumentation System (SIRCIS) which is a digital controller. This control system continues to evolve with SIRCIS V2 currently in operation. The continual enhancement of the facility, instruments and systems at the SLOWPOKE-2 at RMCC will be discussed, including an update on RMCC's refueling plan. (author)

Plasma-catalyst hybrid reactor with CeO2/γ-Al2O3 for benzene decomposition with synergetic effect and nano particle by-product reduction.

Science.gov (United States)

Mao, Lingai; Chen, Zhizong; Wu, Xinyue; Tang, Xiujuan; Yao, Shuiliang; Zhang, Xuming; Jiang, Boqiong; Han, Jingyi; Wu, Zuliang; Lu, Hao; Nozaki, Tomohiro

2018-04-05

A dielectric barrier discharge (DBD) catalyst hybrid reactor with CeO 2 /γ-Al 2 O 3 catalyst balls was investigated for benzene decomposition at atmospheric pressure and 30 °C. At an energy density of 37-40 J/L, benzene decomposition was as high as 92.5% when using the hybrid reactor with 5.0wt%CeO 2 /γ-Al 2 O 3 ; while it was 10%-20% when using a normal DBD reactor without a catalyst. Benzene decomposition using the hybrid reactor was almost the same as that using an O 3 catalyst reactor with the same CeO 2 /γ-Al 2 O 3 catalyst, indicating that O 3 plays a key role in the benzene decomposition. Fourier transform infrared spectroscopy analysis showed that O 3 adsorption on CeO 2 /γ-Al 2 O 3 promotes the production of adsorbed O 2 - and O 2 2‒ , which contribute benzene decomposition over heterogeneous catalysts. Nano particles as by-products (phenol and 1,4-benzoquinone) from benzene decomposition can be significantly reduced using the CeO 2 /γ-Al 2 O 3 catalyst. H 2 O inhibits benzene decomposition; however, it improves CO 2 selectivity. The deactivated CeO 2 /γ-Al 2 O 3 catalyst can be regenerated by performing discharges at 100 °C and 192-204 J/L. The decomposition mechanism of benzene over CeO 2 /γ-Al 2 O 3 catalyst was proposed. Copyright © 2017 Elsevier B.V. All rights reserved.

Results of charpy V-notch impact testing of structural steel specimens irradiated at ∼30 degrees C to 1 x 1016 neutrons/cm2 in a commercial reactor cavity

International Nuclear Information System (INIS)

Iskander, S.K.; Stoller, R.E.

1997-04-01

A capsule containing Charpy V-notch (CVN) and mini-tensile specimens was irradiated at ∼ 30 degrees C (∼ 85 degrees F) in the cavity of a commercial nuclear power plant to a fluence of 1 x 10 16 neutrons/cm 2 (> 1MeV). The capsule included six CVN impact specimens of archival High Flux Isotope Reactor A212 grade B ferritic steel and five CVN impact specimens of a well-studied A36 structural steel. This irradiation was part of the ongoing study of neutron-induced damage effects at the low temperature and flux experienced by reactor supports. The plant operators shut down the plant before the planned exposure was reached. The exposure of these specimens produced no significant irradiation-induced embrittlement. Of interest were the data on unirradiated specimens in the L-T orientation machined from a single plate of A36 structural steel, which is the same specification for the structural steel used in some reactor supports. The average CVN energy of five unirradiated specimens obtained from one region of the plate and tested at room temperature was ∼ 99 J, while the energy of 11 unirradiated specimens from other locations of the same plate was 45 J, a difference of ∼ 220%. The CVN impact energies for all 18 specimens ranged from a low of 32 J to a high of 111 J. Moreover, it appears that the University of Kansas CVN impact energy data of the unirradiated specimens at the 100-J level are shifted toward higher temperatures by about 20 K. The results were an example of the extent of scatter possible in CVN impact testing. Generic values for the CVN impact energy of A36 should be used with caution in critical applications

IGORR 2: Proceedings of the 2. meeting of the International Group On Research Reactors

Energy Technology Data Exchange (ETDEWEB)

NONE

1992-07-01

The International group on Research Reactors was formed to facilitate the sharing of knowledge and experience among those institutions and individuals who are actively working to design, build, and promote new research reactors or to make significant upgrades to existing facilities. Sessions during this second meeting were devoted to research reactor reports (GRENOBLE reactor, FRM-II, HIFAR, PIK, reactors at JAERI, MAPLE, ANS, NIST, MURR, TRIGA, BR-2, SIRIUS 2); other neutron sources; and two workshops were dealing with research and development results and needs and reports on progress in needed of R and D areas identified at IGORR 1.

IGORR 2: Proceedings of the 2. meeting of the International Group On Research Reactors

International Nuclear Information System (INIS)

1992-01-01

The International group on Research Reactors was formed to facilitate the sharing of knowledge and experience among those institutions and individuals who are actively working to design, build, and promote new research reactors or to make significant upgrades to existing facilities. Sessions during this second meeting were devoted to research reactor reports (GRENOBLE reactor, FRM-II, HIFAR, PIK, reactors at JAERI, MAPLE, ANS, NIST, MURR, TRIGA, BR-2, SIRIUS 2); other neutron sources; and two workshops were dealing with research and development results and needs and reports on progress in needed of R and D areas identified at IGORR 1

Development of Czechoslovak nuclear power engineering

International Nuclear Information System (INIS)

Keher, J.

1985-01-01

The output of Czechoslovak nuclear power plants is envisaged at 2200 MW by 1985, 4400 MW by 1990 and 10,280 MW by the year 2000. The operation so far is assessed of Bohunice V-1 and Bohunice V-2 power plants as is the construction of the Dukovany nuclear power plant. International cooperation in the fulfilment of the nuclear power programme is based on the General Agreement on Cooperation in the Prospective Development and Interlinkage of CMEA Power Systems to the year 1990, the Agreement on Multilateral International Specialization and Cooperation of Production and on Mutual Deliveries of Nuclear Power Plant Equipment. The most important factor in international cooperation is the Programme of Cooperation between the CSSR and the USSR. The primary target in the coming period is the Temelin nuclear power plant project and the establishment of unified control of the nuclear power complex. (M.D.)

Chapter 2. The production units

International Nuclear Information System (INIS)

1998-01-01

In the second chapter of this CD ROM the production units of the Slovak Electric, Plc. (Slovenske elektrarne, a.s.), are presented. It consist of next paragraphs: (1) Nuclear power plants (A-1 Nuclear Power Plant (History, Technological scheme, basic data are presented); V-1, V-2 Bohunice Nuclear Power Plant (History 1972-1985, technological scheme; nuclear safety, radiation protection, heat supply, international co-operation and basic data are presented); Mochovce Nuclear Power Plant (History 1980-1998, technological scheme, construction completion, milestones of commissioning, safety and environmental protection as well as basic data are included). (2) Conventional sources of energy (Vojany fossil power plant (History 1959-1992, Technological units of power plant, Impact of operation on the environment, Plant of Vojany FPP Renewal and Reconstruction, Basic data are listed), Novaky fossil power plant (History 1949-1998, Technological scheme, current investment construction, basic data, Handlova heating plant). Kosice Combined Heat Power Plant (History 1960-1995, technological scheme, State metrology centre, acredited chemical laboratory, basic data). (3) Hydroelectric power plants (Trencin HPPs: Cierny Vah pumped storage HPP, Liptovska Mara HPP, Orava HPP, Sucany HPP, Miksova HPP, Nosice HPP, Velke Kozmalovce HPP, Gabcikovo HPP, Dubnica HPP, Nove Mesto n/V HPP, Madunice HPP, Kralova HPP) and Dobsina HPPs: (Dobsina HPP, Ruzin HPP, Domasa HPP, small HPPs) are presented

In-pile modelling of nuclear fuel element for the MTR type reactors. Pt. 2

Energy Technology Data Exchange (ETDEWEB)

Farhadi, Kazem [AEOI, Tehran (Iran, Islamic Republic of). Radiations Application Research School

2014-06-15

In part two of the present paper, neutronic properties of the pool-type research reactor core are used to assess the similitude laws derived for out-of-pile modelling of the fuel element. The benchmark reactor used for this purpose is an IAEA 5 MW thermal pool-type research reactor currently in operation. The neutronic properties analysis are based on typical 2 200 m/sec and neutrons having 0.025 eV energy. The non-leakage capability of the system is estimated in terms of diffusion length. Also the slowing down power and the moderating ratio of the modelled methanol coolant are calculated in terms of lethargy of the diffusing medium. It is shown that the Iron which is substituted for Aluminium cladding is a relatively low absorber of neutrons but has a high neutron leakage. Methanol which replaced ordinary water as coolant is not a suitable coolant due to high neutrons absorbing substance. It is concluded that although Iron as a cladding material and methanol as a coolant meet the modelling out-of-pile criteria but are not satisfying neutronic properties. Therefore, use of them as a model clad and coolant are not suggested for research reactors. (orig.)

Compatibility of vanadium alloys with reactor-grade helium for fusion reactor applications

International Nuclear Information System (INIS)

Bell, G.E.C.; Bishop, P.S.

1993-01-01

Tests were conducted to determine the compatibility of vanadium alloys with reactor-grade helium and to define the helium gas chemistry requirements for fusion reactors, miniature tensile specimens of V-5Cr-5Ti. V-10Cr-5Ti, and V-12.5Cr-5 Ti were exposed in a once-through system to helium with 70 vppm-H 2 (measured oxygen partial pressures of 10 -12 atm) and bottle helium (measured oxygen partial pressures of -4 atm) between 500 and 700 degree C for up to 1008 h. The weight changes in the specimens were recorded. The helium-exposed specimens were tensile tested, and the effects of exposure on mechanical properties were assessed. Exposure between 500 and 700 degree C for 1008 h in He+70 vppm-H 2 resulted in complete embrittlement of all the alloys in room temperature tensile tests. The fracture mode was primarily cleavage, probably caused by a hydrogen-induced shift in the ductile to brittle transition temperature (DBTT). Weight gains increased with temperature and were largest for the V-5Cr-5Ti alloy. Specimens exposed for 531 h between 500 and 700 degree C in bottle He exhibited two distinct fracture morphologies on the fracture surfaces. Brittle cleavage around the edges of specimens gave way to ductile dimpling in the center of the specimens. The brittle region around the periphery of the specimen is most likely the highest vanadium oxide. V 2 O 5

Characterization of the Three Mile Island Unit-2 reactor building atmosphere prior to the reactor building purge

International Nuclear Information System (INIS)

Hartwell, J.K.; Mandler, J.W.; Duce, S.W.; Motes, B.G.

1981-05-01

The Three Mile Island Unit-2 reactor building atmosphere was sampled prior to the reactor building purge. Samples of the containment atmosphere were obtained using specialized sampling equipment installed through penetration R-626 at the 358-foot (109-meter) level of the TMI-2 reactor building. The samples were subsequently analyzed for radionuclide concentration and for gaseous molecular components (O 2 , N 2 , etc.) by two independent laboratories at the Idaho National Engineering Laboratory (INEL). The sampling procedures, analysis methods, and results are summarized

Reactor Physics Development for Advanced Gas-Cooled Reactors; Recherches en Physique des Reacteurs, pour des Reacteurs Perfectionnes Refroidis par un Gaz; Razrabotka metodov v oblasti reaktornoj fiziki dlya usovershenstvovannogo reaktora s gazovym okhlazhdeniem; Progresos de la Fisica de los Reactores de Tipo Avanzado Refrigerados por Gas

Energy Technology Data Exchange (ETDEWEB)

Moore, J. [United Kingdom Atomic Energy Authority (United Kingdom)

1964-04-15

metodos de medicion de los efectos de la reactividad en APEX, HERO y AGR, y para determinar los datos relativos a la estructura fina y a la distribucion de la potencia en los conjuntos combustibles complejos. Los trabajos se concentran principalmente en el desarrollo de un metodo capaz de sustituir al 'hetrecontrol' y al 'FTD2' , para los cuerpos de reactor cuando el combustible haya alcanzado un grado de combustion considerable. La finalidad del programa experimental con la instalacion HERO es precisamente comprobar estos metodos con cuerpos complejos, inclusive con combustible que contenga plutonio. La explotacion del reactor AGR y las mediciones fisicas que se realicen con el combustible despues de la irradiacion permitiran obtener datos adicionales sobre el efecto del plutonio. (author) [Russian] Rassmatrivaetsja tshhatel'naja jeksperimental'naja i teoreticheskaja rabota, provedennaja pri konstruirovanii, stroitel'stve i vvode v jekspluataciju Uindskejlskogo usovershenstvovannogo reaktora s gazovym ohlazhdeniem i pri okazanii obshhej pomoshhi pri razrabotke usovershenstvovannogo reaktora s gazovym ohlazhdeniem (AGR) dla proizvodstva jenergii dlja grazhdanskih celej. Daetsja opisanie znachitel'nogo ob{sup e}ma rabot, kotorye byli neobhodimy dlja razrabotki prigodnyh teoreticheskih metodov rascheta: 1) raspredelenija potoka i balansa reaktivnosti v slozhnoj aktivnoj zone reaktora; 2) raspredelenija jenergii v toplive so slozhnoj geometriej i 3) vlijanija obluchenija na toplivnye cikly i raspredelenie jenergii. V kachestve vvedenija delaetsja ssylka na jeksperimental'nye dannye i teoreticheskie metody, poluchennye v rezul'tate rabot nad uranovo-magnoksovymi sistemami, i na jeksperimental'nye dannye, poluchennye v rezul'tate Sovmestnoj jeksperimental'noj programmy Britanskoj promyshlennosti (BICEP), kotorye javilis' otpravnym momentom v razrabotke teoreticheskih metodov, primenimyh k usovershenstvovannym reaktoram s gazovym ohlazhdeniem. Dlja opredelenija parametrov

Radiation protection at the RA Reactor in 1998, RA reactor annual report, Part -2

International Nuclear Information System (INIS)

Ninkovic, M.; Pavlovic, R.; Mandic, M.; Pavlovic, S.; Grsic, Z.

1998-01-01

Radiation protection tasks which enable safe operation of the RA reactor, and are defined according the the legal regulations and IAEA safety recommendations are sorted into four categories in this report: (1) Control of the working environment, dosimetry at the RA reactor; (2) Radioactivity control in the vicinity of the reactor and meteorology measurements; (3) Collecting and treatment of fluid effluents; and (4) radioactive wastes, decontamination and actions. Each of the category is described as a separate annex of this report [sr

Active species in a large volume N2-O2 post-discharge reactor

International Nuclear Information System (INIS)

Kutasi, K; Pintassilgo, C D; Loureiro, J; Coelho, P J

2007-01-01

A large volume post-discharge reactor placed downstream from a flowing N 2 -O 2 microwave discharge is modelled using a three-dimensional hydrodynamic model. The density distributions of the most populated active species present in the reactor-O( 3 P), O 2 (a 1 Δ g ), O 2 (b 1 Σ g + ), NO(X 2 Π), NO(A 2 Σ + ), NO(B 2 Π), NO 2 (X), O 3 , O 2 (X 3 Σ g - ) and N( 4 S)-are calculated and the main source and loss processes for each species are identified for two discharge conditions: (i) p = 2 Torr, f = 2450 MHz, and (ii) p = 8 Torr, f = 915 MHz; in the case of a N 2 -2%O 2 mixture composition and gas flow rate of 2 x 10 3 sccm. The modification of the species relative densities by changing the oxygen percentage in the initial gas mixture composition, in the 0.2%-5% range, are presented. The possible tuning of the species concentrations in the reactor by changing the size of the connecting afterglow tube between the active discharge and the large post-discharge reactor is investigated as well

Hydrolytic and radiolytic degradation of TBP in TBP.30% V/V-dodecane/UO2(NO3)2.HNO3.H2O systems

International Nuclear Information System (INIS)

Barreta, L.G.

1980-01-01

The hydrolytic and radiolytic degradation of TBP is investigated in systems of TBP 30% V/V-dodecane/H 2 O . HNO 3 . UO 2 (NO 3 ) 2 by gas chromatographic determination of HDBP. No direct relation between the concentration of HDBP formed and the quantity of HNO 3 extracted by the organic phase is observed in the studies of hydrolysis of TBP. The HDBP concentration is seen to increase non-linearly with the concentration of HNO 3 extracted by the organic phase. Radiolytic studies show that for doses greater than 1 Wh/l, the concentration of HDBP formed increases with the dose absorbed by the system. Whith doses smaller than 1 Wh/l and acid concentration greater than 2 M, two distinct patterns of behavior are observed. The concentration of HDBP as a function of the radiation dose absorbed by the system presents a minimum for uranyl nitrate concentrations smaller than 0.9 M; for uranyl nitrate concentrations greater than 1.3 M the concentration of radiolytic HDBP cannot be calculated because the concentration of the hydrolytic HDBP determined is greater than the sum of the experimental concentrations of hydrolytic and radiolytic HDBP. It is known that the dose absorbed by the process solutions during the reprocessing of light water reactor fuel elements is smaller than one Wh/l. Thus, dose rates between zero and one Wh/l should be studied for this system. (Author) [pt

Safety problems of nuclear power plants with reactors of new generation; Voprosy bezopasnosti v proehktakh AEhS novogo pokoleniya s WWER

Energy Technology Data Exchange (ETDEWEB)

Fedorov, V; Rogov, M; Biryukov, G [Opytno-Konstruktorskoe Byuro Gidropress, Podol` sk (Russian Federation)

1996-12-31

Modernization schemes for safety enhancement of WWER-1000 reactors are proposed. In the case of WWER-1000/V-392 it is based on introduction of additional safety systems and overall design improvement. For WWER-1100 (1000-1100 MW) the safety is enhanced by passive systems built from two-stage heat exchangers. For WWER-500/600 the use of passive safety system is extended to emergency cooling of the active zone and removal of the residual heat emissions from the reactor. The technical characteristics of the three reactors are compared. 3 figs., 1 tab.

G 2 reactor project; Projet de pile a double fin: G 2

Energy Technology Data Exchange (ETDEWEB)

Ailleret, [Electricite de France (EDF), Dir. General des Etudes de Recherches, 75 - Paris (France); Taranger, P; Yvon, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1955-07-01

The CEA actually constructs the G-2 reactor core working with natural uranium, which will use graphite as moderator, and gas under pressure as cooling fluid. This report presents the specificity of the new reactor: - the different elements of the reactor core, - the control and the security of the reactor, - the renewal of the fuel, - the biologic surrounding wall, - and the cooling circuit. (M.B.) [French] le Commissariat a l'Energie Atomique construit actuellement la pile G-2 a Uranium naturel, qui utilisera le graphite comme moderateur, et le gaz sous pression comme fluide de refroidissement. Ce rapport presente les specificite du nouveau reacteur: - les differents elements de la pile, - le controle et la securite du reacteur, - le renouvellement du combustible, - l'enceinte biologique, - et le circuit de refroidissement. (M.B.)

Reactor handbook. 2. rev. ed.

International Nuclear Information System (INIS)

Lederer, B.J.; Wildberg, D.W.

1992-01-01

On the basis of the guidelines on expert knowledge, the book discusses the subjects of atomic physics, heat transfer, nuclear power plants, reactor materials, radiation protection, reactor safety, reactor instrumentation, and reactor operation, with special regard to nuclear power plants with LWR-type reactors. The book is intended for shift personnel, especially gang bosses, reactor operators, and control station operators: for this reason a practical and rather popular style has been chosen. However, the book will also be a manual for other operating personnel, personnel of producer companies, expert organisations, authorities, and students. It can be used as a textbook for staff training, a manual for the practice, and as accompanying book for teaching at nuclear engineering schools. (orig.) With 173 figs [de

Feasibility studies for decommissioning

International Nuclear Information System (INIS)

Hladky, E.

2000-01-01

In this presentation author deals with planning of decommission of the NPPs A1, V1 and V2 Bohunice and Mochovce. It was concluded that: Used model for decommissioning parameters assessment has been suitable for elaboration of initial decommissioning plans (feasibility studies); Basic assessment of main decommissioning parameters and basic comparison of various decommissioning options have been possible; Improvement of the model and corresponding software is desirable and works on software improvement began one year ago; V1-NPP initial decommissioning plan should be actualized, because initial decommissioning plan does not correspond by its content and structure to requirements of Act No. 130/98 and Nuclear Regulatory Authority Degree No. 246/99; Strategy of radioactive wastes treatment and conditioning together with technical provisions at Jaslovske Bohunice site was changed in comparison with the assumptions in 1991-92; Considered V1 NPP decommissioning options are necessary to be re-evaluated in accordance with latest development of knowledge and approaches to NPP decommissioning in the world; Specific unit costs are substantially and differentially changed in comparison with the assumptions in 1991-92; Necessity to take into account technical changes resulted from V1 NPP reconstruction. (author)

ZOCO V - a computer code for the calculation of time-dependent spatial pressure distribution in reactor containments

International Nuclear Information System (INIS)

Mansfeld, G.; Schally, P.

1978-06-01

ZOCO V is a computer code which can calculate the time- and space- dependent pressure distribution in containments of water-cooled nuclear power reactors (both full pressure containments and pressure suppression systems) following a loss-of-coolant accident, caused by the rupture of a main coolant or steam pipe

Microstructure alterations in the base material, heat affected zone and weld metal of a 440-VVER-reactor pressure vessel caused by high fluence irradiation during long term operation: material: 15 Ch2MFA {approx} 0, 15 C-2,5 Cr-0, 7Mo-0,3 V; Veraenderungen der Mikrostruktur in Grundwerkstoff, WEZ und Schweissgut eines 440-VVER-Reaktordruckbehaelters, verursacht durch Neutronenbestrahlung im langzeitigen Betrieb; Werkstoff: 15 Ch2MFA {approx} 0,15 C-2,5 Cr-0, 7Mo-0,3 V

Energy Technology Data Exchange (ETDEWEB)

Maussner, G; Scharf, L; Langer, R [Siemens AG Energieerzeugung KWU, Erlangen (Germany); Gurovich, B [Russian Research Centre Kurchatov Inst., Moscow (Russian Federation)

1998-11-01

Within the scope of the Tacis `91/1.1 project of the European Community, ``Reactor Vessel Embrittlement``, specimens were taken from the heavily irradiated circumferential welds of a VVER pressure vessel. The cumulated fast neutron fluence in the specimens amounts to up to 6.5 x 10{sup 19} cm{sup -}2 (E > 0.5 MeV). For the multi-laboratory, coordinated study, the specimens were cutted for mechanical testing as well as analytical, microstructural and microanalytical examinations in the base metal, HAZ and weld metal with respect to the effects of reactor operatio and post-irradiation annealing as well as thermal treatment (475 C, 560 C). The analytical transmission electron microscopy (200 kV) revealed the alterations found in the mechanical properties to be due to the formation of black dots and irradiation-induced segregations and accumulations of copper and carbides. These effects, caused by operation, (neutron radiation, temperature), are much more significant in the HAZ than in the base metal. (orig./CB) [Deutsch] Im Rahmen des von der Europaeischen Union beauftragten Tacis `91/1.1 Programms `Reactor Vessel Embrittlement` wurden Bohrkerne aus dem hochbestrahlten Rundnahtbereich eines VVER-Reaktordruckbehaelters entnommen. Die kumulierte schnelle Neutronenfluenz in diesen Proben betraegt bis zu 6,5 x 10{sup 19} cm{sup -2} (E>0,5 MeV). In einer gemeinschaftlichen Untersuchung wurden mechanisch-technologische, chemische sowie mirkostrukturelle Untersuchungen an Grundwerkstoff-, WEZ- und Schweissgutproben im vergleichbaren Ausgangs-, bestrahlten und anschliessend waermebehandelten (475 C, 560 C) Werkstoffzustand durchgefuehrt. Die analytische Durchstrahlelektronenmikroskopie (200 kV) laesst als Ursache fuer die festgestellten Veraenderungen der mechanischen Eigenschaften die Bildung von Versetzungsringen (black dots) sowie von bestrahlungsinduzierten Ausscheidungen und Anreicherungen von Kupfer in den Karbiden erkennen. Diese Effekte, als Folge der betrieblichen

A search for muon neutrino to electron neutrino oscillations at Δm² > 0.1 eV²

Energy Technology Data Exchange (ETDEWEB)

Patterson, Ryan Benton [Princeton Univ., NJ (United States)

2007-11-01

The evidence is compelling that neutrinos undergo flavor change as they propagate. In recent years, experiments have observed this phenomenon of neutrino oscillations using disparate neutrino sources: the sun, fission reactors, accelerators, and secondary cosmic rays. The standard model of particle physics needs only simple extensions - neutrino masses and mixing - to accommodate all neutrino oscillation results to date, save one. The 3.8σ-significant $\\bar{v}$_e excess reported by the LSND collaboration is consistent with $\\bar{v}$_μ →$\\bar{v}$_e oscillations with a mass-squared splitting of Δm² ~ 1 eV². This signal, which has not been independently verified, is inconsistent with other oscillation evidence unless more daring standard model extensions (e.g. sterile neutrinos) are considered.

Annual report on JEN-1 and JEN-2 Reactors; Informe periodico de Reactores JEN-1 y JEN-2 correpondiente al ano 1972

Energy Technology Data Exchange (ETDEWEB)

Montes Ponce de Leon, J.

1974-07-01

In the annual report on the JEN-1 and JEN-2 reactors the main fractures of the reactor operations and maintenance are described. The reactor has been in operation for 2188 hours, what means 74% of the total working time. Maintenance and periodical tests have occupied the rest of the time. Maintenance operations are shown according to three main subjects, the main failures so as the reactor scrams are also described. Different date relating with radiation level and health Physics are also included. (Author)

A SAS2H/KENO-V methodology for 3D fuel burnup analysis

International Nuclear Information System (INIS)

Milosevic, M.; Greenspan, E.; Vujic, J.

2002-01-01

An efficient methodology for 3D fuel burnup analysis of LWR reactors is described in this paper. This methodology is founded on coupling Monte Carlo method for 3D calculation of node power distribution, and transport method for depletion calculation in ID Wigner-Seitz equivalent cell for each node independently. The proposed fuel burnup modeling, based on application of SCALE-4.4a control modules SAS2H and KENO-V.a is verified for the case of 2D x-y model of IRIS 15 x 15 fuel assembly (with reflective boundary condition) by using two well benchmarked code systems. The one is MOCUP, a coupled MCNP-4C and ORIGEN2.1 utility code, and the second is KENO-V.a/ORIGEN2.1 code system recently developed by authors of this paper. The proposed SAS2H/KENO-V.a methodology was applied for 3D burnup analysis of IRIS-1000 benchmark.44 core. Detailed k sub e sub f sub f and power density evolution with burnup are reported. (author)

Control of WWER-440 nuclear reactor

International Nuclear Information System (INIS)

Wagner, K.; Drab, F.; Grof, V.

1978-01-01

The V-1 reactor control systems are described. The data acquisition and processing system fulfils four main functions, ie., reactor start-up and power increase to 10% of the rated power, automatic power control within 3% and 110% of the rated power, reactivity compensation, and reactor protection. The automatic control system ensures constant steam pressure maintained with an accuracy of +-0.05 MPa. Reactivity compensation and spatial power distribution is mainly safeguarded by boric acid control. The V-1 reactor protection system has four levels of accident protection depending on the gravity of the failure. The philosophy of automation of the V-1 reactor control and protection system is based on autonomous automatic controlers and on the direct control of the individual sets and technological equipment. In conclusion, development trends are briefly outlined of control and protection systems of light water reactor power plants. (Z.M.)

Monitoring program of surrounding of the NPP SE-EBO

International Nuclear Information System (INIS)

Dobis, L.; Kostial, J.

1997-01-01

The paper dealt with monitoring program of radiation control of surrounding of the NPP Bohunice, which has the aim: (1) to ensure the control of influence of work of the NPP Bohunice on the environment in their surrounding; (2) to ensure the back-ground for regular brief of control and supervisory organs about condition of the environment in surrounding of the NPP Bohunice; (3) to maintain the expected technical level of control of the NPP Bohunice and to exploit optimally the technical means; (4) to solicit permanently the data about the radioactivity of environment in surrounding of the NPP Bohunice for forming of files of the data; (5) to exploit purposefully the technical equipment, technical workers and to maintain their in permanent emergency and technical eligibility for the case of the breakdown; (6) to obtain permanently the files of the values for qualification of the reference levels. This program of monitoring includes the radiation control of surrounding of the NPP Bohunice, in the time of normal work of power-station's blocks, inclusively of all types of trouble-shooting and repairer works in surrounding of the NPP Bohunice, up to distance 20 km from power-station. The monitoring includes: outlets from the NPP Bohunice, monitoring of radiation characteristics in surrounding of the NPP Bohunice, (aerosols, fall-outs, soil), the links of food chains: (grass and fodder, milk, agriculture products), hydrosphere in surrounding (surface waters, drink water, bores of radiation control in complex of the NPP Bohunice, components of the hydrosphere), measurement of radiation from external sources (measurement of the dose rates, measurement of the doses [sk

The bent crystal diffraction spectrometer at the BR2 reactor in Mol

Science.gov (United States)

Kaerts, E.; Jacobs, L.; Vandenput, G.; Van Assche, P. H. M.

1988-05-01

The DuMond-type bent crystal diffraction spectrometer installed at the BR2 reactor in Mol is presented. The spectrometer is mainly designed to study nuclear γ-transitions following thermal neutron capture. It covers the energy interval 25 ≦ Eγ ≦ 1500 keV. Instead of the traditionally used quartz crystals, a highly perfect silicium crystal is chosen as analysing crystal. Diffraction occurs from the (220) plane. The "quasi-mosaic" width, introduced by bending the crystal, is as small as 0.2″. The integrated reflecting power R of the bent crystal stays constant up to 1.5 MeV in first, 680 keV in second and 300 keV in third diffraction order. For higher photon energies, only an E-1 energy dependence is observed in second and third diffraction order. Consequently, besides improving the energy resolution, the use of these silicium crystals substantially increases the spectrometer efficiency and extends the high energy limit of bent crystal diffraction spectrometers. The diffraction angles are measured with a symmetrical interferometer system which covers an angular range of -6° to +6° with a precision of about 0.01″. Minimum diffraction line widths of 0.9″ have been measured, corresponding to an energy resolution ΔE = 1.35 × 10 -6E2n-1 keV -1. The dominant contribution to the observed line widths arises from the finite extent of the source.

Final report for the 2nd Ex-Vessel Neutron Dosimetry Installations and Evaluations for Yonggwang Unit 2 Reactor Pressure Vessel

Energy Technology Data Exchange (ETDEWEB)

Kim, Byoung Chul; Yoo, Choon Sung; Lee, Sam Lai; Gong, Un Sik; Choi, Kwon Jae; Chung, Kyoung Ki; Kim, Kwan Hyun; Chang, Jong Hwa; Ha, Jea Ju

2008-01-15

This report describes a neutron fluence assessment performed for the Yonggwang Unit 2 pressure vessel beltline region based on the guidance specified in Regulatory Guide 1.190. In this assessment, maximum fast neutron exposures expressed in terms of fast neutron fluence (E>1 MeV) and iron atom displacements (dpa) were established for the beltline region of the pressure vessel. During Cycle 16 of reactor operation, an Ex-Vessel Neutron Dosimetry Program was instituted at Yonggwang Unit 2 to provide continuous monitoring of the beltline region of the reactor vessel. The use of the Ex-Vessel Neutron Dosimetry Program coupled with available surveillance capsule measurements provides a plant specific data base that enables the evaluation of the vessel exposure and the uncertainty associated with that exposure over the service life of the unit. Ex-Vessel Neutron Dosimetry has been evaluated at the conclusion of Cycle 16.

Simulation of VVER MCCI reactor test case with ASTEC V2/MEDICIS computer code

International Nuclear Information System (INIS)

Stefanova, A.; Grudev, P.; Gencheva, R.

2011-01-01

This paper presents an application of the ASTEC v2, module MEDICIS for simulation of VVER Molten core concrete interaction test (MCCI) case without water injection. The main purpose of performed calculation is verification and improvement of module MEDICIS/ASTECv2 for better simulation of core concrete interaction processes. The VVER-1000 reference nuclear power plant was chosen as SARNET2 benchmark MCCI test-case. The initial conditions for MCCI test are taken after SBO scenario calculated with ASTEC version 1.3R2 by INRNE. (authors)

VERONA V6.22 – An enhanced reactor analysis tool applied for continuous core parameter monitoring at Paks NPP

Energy Technology Data Exchange (ETDEWEB)

Végh, J., E-mail: janos.vegh@ec.europa.eu [Institute for Energy and Transport of the Joint Research Centre of the European Commission, Postbus 2, NL-1755 ZG Petten (Netherlands); Pós, I., E-mail: pos@npp.hu [Paks Nuclear Power Plant Ltd., H-7031 Paks, P.O. Box 71 (Hungary); Horváth, Cs., E-mail: csaba.horvath@energia.mta.hu [Centre for Energy Research, Hungarian Academy of Sciences, H-1525 Budapest 114, P.O. Box 49 (Hungary); Kálya, Z., E-mail: kalyaz@npp.hu [Paks Nuclear Power Plant Ltd., H-7031 Paks, P.O. Box 71 (Hungary); Parkó, T., E-mail: parkot@npp.hu [Paks Nuclear Power Plant Ltd., H-7031 Paks, P.O. Box 71 (Hungary); Ignits, M., E-mail: ignits@npp.hu [Paks Nuclear Power Plant Ltd., H-7031 Paks, P.O. Box 71 (Hungary)

2015-10-15

Between 2003 and 2007 the Hungarian Paks NPP performed a large modernization project to upgrade its VERONA core monitoring system. The modernization work resulted in a state-of-the-art system that was able to support the reactor thermal power increase to 108% by more accurate and more frequent core analysis. Details of the new system are given in Végh et al. (2008), the most important improvements were as follows: complete replacement of the hardware and the local area network; application of a new operating system and porting a large fraction of the original application software to the new environment; implementation of a new human-system interface; and last but not least, introduction of new reactor physics calculations. Basic novelty of the modernized core analysis was the introduction of an on-line core-follow module based on the standard Paks NPP core design code HELIOS/C-PORCA. New calculations also provided much finer spatial resolution, both in terms of axial node numbers and within the fuel assemblies. The new system was able to calculate the fuel applied during the first phase of power increase accurately, but it was not tailored to determine the effects of burnable absorbers as gadolinium. However, in the second phase of the power increase process the application of fuel assemblies containing three fuel rods with gadolinium content was intended (in order to optimize fuel economy), therefore off-line and on-line VERONA reactor physics models had to be further modified, to be able to handle the new fuel according to the accuracy requirements. In the present paper first a brief overview of the system version (V6.0) commissioned after the first modernization step is outlined; then details of the modified off-line and on-line reactor physics calculations are described. Validation results for new modules are treated extensively, in order to illustrate the extent and complexity of the V&V procedure associated with the development and licensing of the new

Optimized Control Rods of the BR2 Reactor

Energy Technology Data Exchange (ETDEWEB)

Kalcheva, Silva; Koonen, E.

2007-09-15

At the present time the BR-2 reactor uses control elements with cadmium as neutron absorbing part. The lower section of the control element is a beryllium assembly cooled by light water. Due to the burn up of the lower end of the cadmium section during the reactor operation, the presently used rods for reactivity control of the BR-2 reactor have to be replaced by new ones. Considered are various types Control Rods with full active part of the following materials: cadmium (Cd), hafnium (Hf), europium oxide (Eu2O3) and gadolinium (Gd2O3). Options to decrease the burn up of the control rod material in the hot spot, such as use of stainless steel in the lower active part of the Control Rod are discussed. Comparison with the characteristics of the presently used Control Rods types is performed. The changing of the characteristics of different types Control Rods and the perturbation effects on the reactor neutronics during the BR-2 fuel cycle are investigated. The burn up of the Control Rod absorbing material, total and differential control rods worth, macroscopic and effective microscopic absorption cross sections, fuel and reactivity evolution are evaluated during approximately 30 operating cycles.

Optimized Control Rods of the BR2 Reactor

International Nuclear Information System (INIS)

Kalcheva, Silva; Koonen, E.

2007-01-01

At the present time the BR-2 reactor uses control elements with cadmium as neutron absorbing part. The lower section of the control element is a beryllium assembly cooled by light water. Due to the burn up of the lower end of the cadmium section during the reactor operation, the presently used rods for reactivity control of the BR-2 reactor have to be replaced by new ones. Considered are various types Control Rods with full active part of the following materials: cadmium (Cd), hafnium (Hf), europium oxide (Eu2O3) and gadolinium (Gd2O3). Options to decrease the burn up of the control rod material in the hot spot, such as use of stainless steel in the lower active part of the Control Rod are discussed. Comparison with the characteristics of the presently used Control Rods types is performed. The changing of the characteristics of different types Control Rods and the perturbation effects on the reactor neutronics during the BR-2 fuel cycle are investigated. The burn up of the Control Rod absorbing material, total and differential control rods worth, macroscopic and effective microscopic absorption cross sections, fuel and reactivity evolution are evaluated during approximately 30 operating cycles.

Study on neutron capture cross sections using the filtered neutron beams of 55 keV and 144 keV at the Dalat reactor and related applications

International Nuclear Information System (INIS)

Vuong Huu Tan; Nguyen Canh Hai; Pham Ngoc Son; Tran Tuan Anh

2007-01-01

In this fundamental research project on nuclear physics in period of 2006, the neutron capture cross sections for the reactions of 139 La (n,γ) 140 La, 152 Sm (n,γ) 153 Sm, 191 Ir (n,γ) 192 Ir and 193 Ir (n,γ) 194 Ir have been measured at 55 keV and 144 keV by the activation method using the filtered neutron beams of the Dalat nuclear research reactor. The cross sections were determined relative to the standard capture cross sections of 197 Au. The samples and standard were prepaid from high purity (99.99%) foil of Au and natural oxide powders of La 2 O 3 , Sm 2 O 3 and IrO 2 . A high efficient HPGe detector (58%) was used to detect the gamma rays, emitted from the activated samples. The absolute efficiency curve of the detector has been precisely calibrated thanks to a set of standard radioisotope sources and a multi-nuclide standard solution, supported by IAEA. The present results were compared with the previous measurements from EXFOR-2003, and the evaluated values of JENDL 3.3 and ENDF/B-6.8. (author)

Upgrading of the research reactors FRG-1 and FRG-2

International Nuclear Information System (INIS)

Krull, W.

1981-01-01

In 1972 for the research reactor FRG-2 we applied for a license to increase the power from 15 MW to 21 MW. During this procedure a public laying out of the safety report and an upgrading procedure for both research reactors - FRG-1 (5 MW) and FRG-2 - were required by the licensing authorities. After discussing the legal background for licensing procedures in the Federal Republic of Germany the upgrading for both research reactors is described. The present status and future licensing aspects for changes of our research reactors are discussed, too. (orig.) [de

PSA analysis focused on Mochovce NPP safety measures evaluation from operational safety point of view

International Nuclear Information System (INIS)

Cillik, I.; Vrtik, L.

2001-01-01

Mochovce NPP consists of four reactor units of WWER 440/V213 type and it is located in the south-middle part of Slovakia. At present first unit operated and the second one under the construction finishing. As these units represent second generation of WWER reactor design, the additional safety measures (SM) were implemented to enhance operational and nuclear safety according to the recommendations of performed international audits and operational experience based on exploitation of other similar units (as Dukovany and J. Bohunice NPPs). These requirements result into a number of SMs grouped according to their purpose to reach recent international requirements on nuclear and operational safety. The paper presents the bases used for safety measures establishing including their grouping into the comprehensive tasks covering different areas of safety goals as well as structural organization of a project management of including participating companies and work performance. More, results are given regarding contribution of selected SMs to the total core damage frequency decreasing.(author)

Mochovce NPP safety measures evaluation from point of view of operational safety enhancement

International Nuclear Information System (INIS)

Cillik, I.; Vrtik, L.

2000-01-01

Mochovce NPP consists of four reactor units of WWER 440/V213 type and it is located in the south-middle part of Slovakia. At present first unit operated and the second one under the construction finishing. As these units represent second generation of WWER reactor design, the additional safety measures (SM) were implemented to enhance operational and nuclear safety according to the recommendations of performed international audits and operational experience based on exploitation of other similar units (as Dukovany and J. Bohunice NPPs). These requirements result into a number of SMs grouped according to their purpose to reach recent international requirements on nuclear and operational safety. The paper presents the bases used for safety measures establishing including their grouping into the comprehensive tasks covering different areas of safety goals as well as structural organization of a project management of including participating companies and work performance. More, results are given regarding contribution of selected SMs to the total core damage frequency decreasing. (author)

Calculation of external exposure during transport and disposal of radioactive waste arisen from dismantling of steam generator

International Nuclear Information System (INIS)

Hornacek, M.; Necas, V.

2014-01-01

The dismantling of large components (reactor pressure vessel, reactor internals, steam generator) represents complex of processes involving preparation, dismantling, waste treatment and conditioning, transport and final disposal. To optimise all of these activities in accordance with the ALARA principle the prediction of the exposure of workers is an essential prerequisite. The paper deals with the calculation of external exposure of workers during transport and final disposal of heat exchange tubes of steam generator used in Slovak nuclear power plant V1 in Jaslovske Bohunice. The type of waste packages, the calculation models of truck and National Radioactive Waste Repository in Mochovce are presented. The detailed methodology of radioactive waste disposal is showed and the degree of influence of time decay (0, 5 and 10 years) on the radiological conditions during transport and disposal is studied. All of the results do not exceed the limits given in Slovak and international regulatory documents. (authors)

Reactor physics experiments in PURNIMA sub critical facility coupled with 14 MeV neutron source

International Nuclear Information System (INIS)

Kumar, Rajeev; Degweker, S.B.; Patel, Tarun; Bishnoi, Saroj; Adhikari, P.S.

2011-01-01

Accelerator Driven Sub-critical Systems (ADSS) are attracting increasing worldwide attention due to their superior safety characteristics and their potential for burning actinide and fission product waste and energy production. A number of countries around the world have drawn up roadmaps/programs for development of ADSS. Indian interest in ADSS has an additional dimension, which is related to the planned utilization of our large thorium reserves for future nuclear energy generation. A programme for development of ADSS is taken up at the Bhabha Atomic Research Centre (BARC) in India. This includes R and D activities for high current proton accelerator development, target development and Reactor Physics studies. As part of the ADSS Reactor Physics research programme, a sub-critical facility is coming up in BARC which will be coupled with an existing D-D/D-T neutron generator. Two types of cores are planned. In one of these, the sub-critical reactor assembly consists of natural uranium moderated by high density polyethylene (HDP) and reflected by BeO. The other consists of natural uranium moderated by light water. The maximum neutron yield of the neutron source with tritium target is around 10 10 neutron per sec. Various reactor physics experiments like measurement of the source strength, neutron flux distribution, buckling estimation and sub-critical source multiplication are planned. Apart from this, measurement of the total fission power and neutron spectrum will also be carried out. Mainly activation detectors will be used in all in-core neutron flux measurement. Measurement of the degree of sub-criticality by various deterministic and noise methods is planned. Helium detectors with advanced data acquisition card will be used for the neutron noise experiments. Noise characteristics of ADSS are expected to be different from that of traditional reactors due to the non-Poisson statistical features of the source. A new theory incorporating these features has been

EURATOM's Programme of Participation in Power Reactor Construction; Le programme de participation d'Euratom aux reacteurs de puissance; Programma uchastiya v razrabotke ehnergeticheskikh reaktorov Evratoma; El programa de participacion de la Euratom en la construccion y explotacion de reactores de potencia

Energy Technology Data Exchange (ETDEWEB)

Ramadier, R. C.; Parker, E. [Communaute Europoenne de l' Energie Atomique, Bruxelles (Belgium)

1963-10-15

One of the means used by the Commission of EURATOM to promote the development of a European nuclear industry is a programme of ''Community participation'', under which the Commission will participate in power reactor construction up to a total expenditure of 32 million European Monetary Agreement units of account. The return for this will be the acquisition of information on the design, construction, start-up and operation of such reactors. So far, proposals from three companies have resulted in the signing of contracts. These companies are: (a) The Societa Elettronucleare Nazionale (SENN), which is constructing a station of 150 MW(e) net in Italy, equipped with a double-cycle boiling-water reactor; (b) The Societa Italiana Meridionale Energia Atomica (SIMEA), which has undertaken to construct a station f 200 MW(e) net in Italy, equipped with a natural uranium-graphite-CO{sub 2} reactor; (c) The Societe d'Energie Nucleaire Franco-Belge des Ardennes (SENA), which has undertaken to construct, on the French-Belgian border, a station which will be equipped with a pressurized-water reactor and whose output will reach, and probably exceed, 242 MW(e) net. Further, the Commission has been requested by the Rheinisch-Westfalisches Elektrizitatswerk - Bayernwerke (RWE-BW) group and the N.V. Samenwerkende Electriciteits-Productiebedrijve to take part in the construction o f two other power reactors - the first a 237 MW(e) double-cycle boiling-water reactor, and the second a 50 MW(e) single-cycle, natural-circulation boiling-water reactor. Community participation can take various forms, one of them being the sharing of any deficit that might result from the production of electricity by the stations during their first years of operation. The effect of EURATOM's participation has been to encourage the construction of some of these nuclear power stations. Moreover, it has resulted in the gathering of extremely useful information and w ill continue to do so in the years to come

The EUCLID/V1 Integrated Code for Safety Assessment of Liquid Metal Cooled Fast Reactors. Part 1: Basic Models

Science.gov (United States)

Mosunova, N. A.

2018-05-01

The article describes the basic models included in the EUCLID/V1 integrated code intended for safety analysis of liquid metal (sodium, lead, and lead-bismuth) cooled fast reactors using fuel rods with a gas gap and pellet dioxide, mixed oxide or nitride uranium-plutonium fuel under normal operation, under anticipated operational occurrences and accident conditions by carrying out interconnected thermal-hydraulic, neutronics, and thermal-mechanical calculations. Information about the Russian and foreign analogs of the EUCLID/V1 integrated code is given. Modeled objects, equation systems in differential form solved in each module of the EUCLID/V1 integrated code (the thermal-hydraulic, neutronics, fuel rod analysis module, and the burnup and decay heat calculation modules), the main calculated quantities, and also the limitations on application of the code are presented. The article also gives data on the scope of functions performed by the integrated code's thermal-hydraulic module, using which it is possible to describe both one- and twophase processes occurring in the coolant. It is shown that, owing to the availability of the fuel rod analysis module in the integrated code, it becomes possible to estimate the performance of fuel rods in different regimes of the reactor operation. It is also shown that the models implemented in the code for calculating neutron-physical processes make it possible to take into account the neutron field distribution over the fuel assembly cross section as well as other features important for the safety assessment of fast reactors.

Fusion reactor design and technology 1986. V. 1

International Nuclear Information System (INIS)

1987-01-01

The first volume of the Proceedings of the Fourth Technical Committee Meeting and Workshop on Fusion Reactor Design and Technology organized by the IAEA (Yalta, 26 May - 6 June 1986) includes 36 papers devoted to the following topics: fusion programmes (3 papers), tokamaks (15 papers), non-tokamak reactors and open systems (9 papers), inertial confinement concepts (5 papers), fission-fusion hybrids (4 papers). Each of these papers has a separate abstract. Refs, figs and tabs

''Sleeping reactor'' irradiations: Shutdown reactor determination of short-lived activation products

International Nuclear Information System (INIS)

Jerde, E.A.; Glasgow, D.C.

1998-01-01

At the High-Flux Isotope Reactor (HFIR) at the Oak Ridge National Laboratory, the principal irradiation system has a thermal neutron flux (φ) of ∼ 4 x 10 14 n/cm 2 · s, permitting the detection of elements via irradiation of 60 s or less. Irradiations of 6 or 7 s are acceptable for detection of elements with half-lives of as little as 30 min. However, important elements such as Al, Mg, Ti, and V have half-lives of only a few minutes. At HFIR, these can be determined with irradiation times of ∼ 6 s, but the requirement of immediate counting leads to increased exposure to the high activity produced by irradiation in the high flux. In addition, pneumatic system timing uncertainties (about ± 0.5 s) make irradiations of 9 Be(γ,n) 8 Be, the gamma rays principally originating in the spent fuel. Upon reactor SCRAM, the flux drops to ∼ 1 x 10 10 n/cm 2 · s within 1 h. By the time the fuel elements are removed, the flux has dropped to ∼ 6 x 10 8 . Such fluxes are ideal for the determination of short-lived elements such as Al, Ti, Mg, and V. An important feature of the sleeping reactor is a flux that is not constant

TEMPERA-V2. A computer program for sensitivity analysis in a cooling channel of nuclear reactors-V.1

International Nuclear Information System (INIS)

Andrade Lima, F.R. de; Alvim, A.C.M.

1986-09-01

The sensitivity of linear responses associated with physical quantities governed by non linear differential systems is studied, using perturbation theory. The equivalence and formal differences of differential and GPT formalisms are shown. Both of them and also the matricial formalism are used for sensitivity calculations of transient problems in a typical PWR coolant channel. The results obtained are encouraging with respect to the potentiality of the method for thermal-hydraulic calculations normally performed for reactor design and safety analysis. (Author) [pt

Annual report on JEN-1 and JEN-2 Reactors

International Nuclear Information System (INIS)

Montes Ponce de Leon, J.

1974-01-01

In the annual report on the JEN-1 and JEN-2 reactors the main fractures of the reactor operations and maintenance are described. The reactor has been in operation for 2188 hours, what means 74% of the total working time. Maintenance and periodical tests have occupied the rest of the time. Maintenance operations are shown according to three main subjects, the main failures so as the reactor scrams are also described. Different date relating with radiation level and health Physics are also included. (Author)

The SPHINX reactor for engineering tests

International Nuclear Information System (INIS)

Adamov, E.O.; Artamkin, K.N.; Bovin, A.P.; Bulkin, Y.M.; Kartashev, E.F.; Korneev, A.A.; Stenbok, I.A.; Terekhov, A.S.; Khmel'Shehikov, V.V.; Cherkashov, Y.M.

1990-01-01

A research reactor known as SPHINX is under development in the USSR. The reactor will be used mainly to carry out tests on mock-up power reactor fuel assemblies under close-to-normal parameters in experimental loop channels installed in the core and reflector of the reactor, as well as to test samples of structural materials in ampoule and loop channels. The SPHINX reactor is a channel-type reactor with light-water coolant and moderator. Maximum achievable neutron flux density in the experimental channels (cell composition 50% Fe, 50% H 2 O) is 1.1 X 10 15 neutrons/cm 2 · s for fast neutrons (E > 0.1 MeV) and 1.7 X 10 15 for thermal neutrons at a reactor power of 200 MW. The design concepts used represent a further development of the technical features which have met with approval in the MR and MIR channel-type engineering test reactors currently in use in the USSR. The 'in-pond channel' construction makes the facility flexible and eases the carrying out of experimental work while keeping discharges of radioactivity into the environment to a low level. The reactor and all associated buildings and constructions conform to modern radiation safety and environmental protection requirements

Hydrogen production with effluent from an ethanol–H2-coproducing fermentation reactor using a single-chamber microbial electrolysis cell

KAUST Repository

Lu, Lu

2009-06-01

Hydrogen can be produced by bacterial fermentation of sugars, but substrate conversion to hydrogen is incomplete. Using a single-chamber microbial electrolysis cell (MEC), we show that additional hydrogen can be produced from the effluent of an ethanol-type dark-fermentation reactor. An overall hydrogen recovery of 83 ± 4% was obtained using a buffered effluent (pH 6.7-7.0), with a hydrogen production rate of 1.41 ± 0.08 m3 H2/m3 reactor/d, at an applied voltage of Eap = 0.6 V. When the MEC was combined with the fermentation system, the overall hydrogen recovery was 96%, with a production rate of 2.11 m3 H2/m3/d, corresponding to an electrical energy efficiency of 287%. High cathodic hydrogen recoveries (70 ± 5% to 94 ± 4%) were obtained at applied voltages of 0.5-0.8 V due to shorter cycle times, and repression of methanogen growth through exposure of the cathode to air after each cycle. Addition of a buffer to the fermentation effluent was critical to MEC performance as there was little hydrogen production using unbuffered effluent (0.0372 m3 H2/m3/d at Eap = 0.6 V, pH 4.5-4.6). These results demonstrate that hydrogen yields from fermentation can be substantially increased by using MECs. © 2009 Elsevier B.V. All rights reserved.

X-ray digital industrial radiography (DIR) for local liquid velocity (V(LL)) measurement in trickle bed reactors (TBRs): validation of the technique.

Science.gov (United States)

Mohd Salleh, Khairul Anuar; Rahman, Mohd Fitri Abdul; Lee, Hyoung Koo; Al Dahhan, Muthanna H

2014-06-01

Local liquid velocity measurements in Trickle Bed Reactors (TBRs) are one of the essential components in its hydrodynamic studies. These measurements are used to effectively determine a reactor's operating condition. This study was conducted to validate a newly developed technique that combines Digital Industrial Radiography (DIR) with Particle Tracking Velocimetry (PTV) to measure the Local Liquid Velocity (V(LL)) inside TBRs. Three millimeter-sized Expanded Polystyrene (EPS) beads were used as packing material. Three validation procedures were designed to test the newly developed technique. All procedures and statistical approaches provided strong evidence that the technique can be used to measure the V(LL) within TBRs.

System Design of a Supercritical CO_2 cooled Micro Modular Reactor

International Nuclear Information System (INIS)

Kim, Seong Gu; Cho, Seongkuk; Yu, Hwanyeal; Kim, Yonghee; Jeong, Yong Hoon; Lee, Jeong Ik

2014-01-01

Small modular reactor (SMR) systems that have advantages of little initial capital cost and small restriction on construction site are being developed by many research organizations around the world. Existing SMR concepts have the same objective: to achieve compact size and a long life core. Most of small modular reactors have much smaller size than the large nuclear power plant. However, existing SMR concepts are not fully modularized. This paper suggests a complete modular reactor with an innovative concept for reactor cooling by using a supercritical carbon dioxide. The authors propose the supercritical CO_2 Brayton cycle (S-CO_2 cycle) as a power conversion system to achieve small volume of power conversion unit (PCU) and to contain the reactor core and PCU in one vessel. A conceptual design of the proposed small modular reactor was developed, which is named as KAIST Micro Modular Reactor (MMR). The supercritical CO_2 Brayton cycle for the S-CO_2 cooled reactor core was optimized and the size of turbomachinery and heat exchanger were estimated preliminary. The nuclear fuel composed with UN was proposed and the core lifetime was obtained from a burnup versus reactivity calculation. Furthermore, a system layout with fully passive safety systems for both normal operation and emergency operation was proposed. (author)

Preliminary design of a tandem mirror reactor

International Nuclear Information System (INIS)

Strohmayer, J.N.

1984-04-01

The purpose of this thesis is to examine the TARA mirror experiment as a possible tandem mirror reactor configuration. This is a preliminary study to size the coil structure based on using the smallest end cell axial length that physics and engineering allow, zeroing the central cell parallel currents and having interchange stability. The input powers are estimated for the final reactor design so a Q value may be estimated. The Q value is defined as the fusion power divided by the total injected power absorbed by the plasma. A computer study was performed on the effect of the transition size, the transition vertical spacing and transition current. These parameters affect the central cell parallel currents, the recircularization of the flux tube and the ratio of central cell beta to anchor beta needed for marginal stability. Two designs were identified. The first uses 100 keV and 13 keV neutral beams to pump the ions that trap in the thermal barrier. The Q value of this reactor is 11.3. The second reactor uses a pump beam at 40 keV. This energy is chosen because there is a resonance for the charge exchange cross section between D 0 and He 2+ at this energy, thus the alpha ash will be pumped along with the deuterium and tritium. The Q value of this reactor is 11.6

The SLOWPOKE-2 reactor with low enrichment uranium oxide fuel

International Nuclear Information System (INIS)

Townes, B.M.; Hilborn, J.W.

1985-06-01

A SLOWPOKE-2 reactor core contains less than 1 kg of highly enriched uranium (HEU) and the proliferation risk is very low. However, to overcome proliferation concerns a new low enrichment uranium (LEU) fuelled reactor core has been designed. This core contains approximately 180 fuel elements based on the Zircaloy-4 clad UOsub(2) CANDU fuel element, but with a smaller outside diameter. The physics characteristics of this new reactor core ensure the inherent safety of the reactor under all conceivable conditions and thus the basic SLOWPOKE safety philosophy which permits unattended operation is not affected

Thermal energy and bootstrap current in fusion reactor plasmas

International Nuclear Information System (INIS)

Becker, G.

1993-01-01

For DT fusion reactors with prescribed alpha particle heating power P α , plasma volume V and burn temperature i > ∼ 10 keV specific relations for the thermal energy content, bootstrap current, central plasma pressure and other quantities are derived. It is shown that imposing P α and V makes these relations independent of the magnitudes of the density and temperature, i.e. they only depend on P α , V and shape factors or profile parameters. For model density and temperature profiles analytic expressions for these shape factors and for the factor C bs in the bootstrap current formula I bs ∼ C bs (a/R) 1/2 β p I p are given. In the design of next-step devices and fusion reactors, the fusion power is a fixed quantity. Prescription of the alpha particle heating power and plasma volume results in specific relations which can be helpful for interpreting computer simulations and for the design of fusion reactors. (author) 5 refs

Quality assurance

International Nuclear Information System (INIS)

1996-01-01

The main efforts of Nuclear Regulatory Authority of the Slovak Republic (NRA SR) was focused on support of quality assurance programmes development at responsible organizations Bohunice V-1 and V-v and Mochovce NPPs and their inspection. Development of the level two documentation of a partial quality assurance programme for NPP operation continued at Mochovce NPP. Most of documentation has been submitted to NRA SR for comments and approval. NRA SR invited a mission of French experts to Mochovce NPP to review preparation and performance of internal audits that would be beneficial for improvement in this kind activities at the NPP. Bohunice NPP continued in development of a partial quality assurance programme for operation. The Quality Assurance Programme submitted to NRA SR for approval. Based on a request of Bohunice NPPs, NRA SR consulted the draft quality assurance programme developed by Siemens for stage of the 'Basic Design' of V-1 NPP upgrading. The programme had not been submitted for approval to NRA SR prior to completion of works by Siemens. Based on an internal audit that had been performed, corrective measures were proposed to meet requirements on review and approval of suppliers quality assurance programmes. Requirements related to the quality assurance at nuclear installations were prepared to be incorporated into principles of a act on peaceful use of nuclear power in Slovak Republic

Operation of the SLOWPOKE-2 reactor in Jamaica

Energy Technology Data Exchange (ETDEWEB)

Grant, C.N.; Lalor, G.C.; Vuchkov, M.K. [University of the West Indies, Kingston (Jamaica)

2001-07-01

Over the past sixteen years lCENS has operated a SLOWPOKE 2 nuclear reactor almost exclusively for the purpose of neutron activation analysis. During this period we have adopted a strategy of minimum irradiation times while optimizing our output in an effort to increase the lifetime of the reactor core and to maintaining fuel integrity. An inter-comparison study with results obtained with a much larger reactor at IPEN has validated this approach. The parameters routinely monitored at ICENS are also discussed and the method used to predict the next shim adjustment. (author)

arXiv Performance of a full scale prototype detector at the BR2 reactor for the SoLid experiment

CERN Document Server

Abreu, Y.; Arnold, L.; Ban, G.; Beaumont, W.; Bongrand, M.; Boursette, D.; Castle, B.C.; Clark, K.; Coupé, B.; Cussans, D.; De Roeck, A.; D'Hondt, J.; Durand, D.; Fallot, M.; Ghys, L.; Giot, L.; Guillon, B.; Ihantola, S.; Janssen, X.; Kalcheva, S.; Kalousis, L.N.; Koonen, E.; Labare, M.; Lehaut, G.; Manzanillas, L.; Mermans, J.; Michiels, I.; Moortgat, C.; Newbold, D.; Park, J.; Pestel, V.; Petridis, K.; Piñera, I.; Pommery, G.; Popescu, L.; Pronost, G.; Rademacker, J.; Ryckbosch, D.; Ryder, N.; Saunders, D.; Schune, M.-H.; Simard, L.; Vacheret, A.; Van Dyck, S.; Van Mulders, P.; van Remortel, N.; Vercaemer, S.; Verstraeten, M.; Weber, A.; Yermia, F.

2018-05-03

The SoLid collaboration has developed a new detector technology to detect electron anti-neutrinos at close proximity to the Belgian BR2 reactor at surface level. A 288 kg prototype detector was deployed in 2015 and collected data during the operational period of the reactor and during reactor shut-down. Dedicated calibration campaigns were also performed with gamma and neutron sources. This paper describes the construction of the prototype detector with a high control on its proton content and the stability of its operation over a period of several months after deployment at the BR2 reactor site. All detector cells provide sufficient light yields to achieve a target energy resolution of better than 20%/√E(MeV). The capability of the detector to track muons is exploited to equalize the light response of a large number of channels to a precision of 3% and to demonstrate the stability of the energy scale over time. Particle identification based on pulse-shape discrimination is demonstrated with calibration so...

Irradiation techniques at BR2 reactor

International Nuclear Information System (INIS)

Hebel, W.

1978-01-01

Since 1963 the material testing reactor BR2 at Mol is operated for the realisation of numerous research programs and experiments on the behavior of materials under nuclear radiation and in particular under intensive neutron exposure. During this period special irradiation techniques and experimental devices were developed according to the desiderata of the different experiments and to the irradiation possibilities offered at BR2. The design and the operating characteristics of quite a number of those irradiation rigs of proven reliability may be used or can be made available for new irradiation experiments. A brief description is given of some typical irradiation devices designed and constructed by CEN/SCK, Technology and Energy Dpt. They are compiled according to their main use for the different research and development programs realized at BR2. Their eventual application however for different objectives could be possible. A final chapter summarizes the principal irradiation conditions offered by BR2 reactor. (author)

The numerical simulation of the WWER-440/V-213 reactor pressure vessel internals response to maximum hypothetical large break loss of coolant accident

International Nuclear Information System (INIS)

Hermansky, P.; Krajcovic, M.

2012-01-01

The reactor internals are designed to ensure cooling of the fuel, to ensure the movement of emergency control assemblies under all operating conditions including accidents and facilitate removal of the fuel and of the internals following an accident This paper presents results of the numerical simulation of the WWER-440/V213 reactor vessel internals dynamic response to maximum hypothetical Large-Break Loss of Coolant Accident. The purpose of this analysis is to determine the reactor vessel internals response due to rapid depressurization and to prove no such deformations occur in the reactor vessel internals which would prevent timely and proper activation of the emergency control assemblies. (Authors)

The Jules Horowitz Reactor project, a driver for revival of the research reactor community

International Nuclear Information System (INIS)

Pere, P.; Cavailler, C.; Pascal, C.

2010-01-01

The first concrete of the nuclear island for the Jules Horowitz Reactor (JHR) was poured at the end of July 2009 and construction is ongoing. The JHR is the largest new platform for irradiation experiments supporting Generation II and III reactors, Generation IV technologies, and radioisotope production. This facility, composed of a unique grouping of workshops, hot cells and hot laboratories together with a first-rate MTR research reactor, will ensure that the process, from preparations for irradiation experiments through post-irradiation non-destructive examination, is completed expediently, efficiently and, of course, safely. In addition to the performance requirements to be met in terms of neutron fluxes on the samples (5x10 14 n.cm -2 /sec -1 E>1 MeV in core and 3,6x10 14 n.cm -2 /sec -1 E<0.625 eV in the reflector) and the JHR's considerable irradiation capabilities (more than 20 experiments and one-tenth of irradiation area for simultaneous radioisotope production), the JHR is the first MTR to be built since the end of the 1960s, making this an especially challenging project. The presentation will provide an overview of the reactor, hot cells and laboratories and an outline of the key milestones in the project schedule, including initial criticality in early 2014 and radioisotope production in 2015. This will be followed by a description of the project organization set up by the CEA as owner and future operator and AREVA TA as prime contractor and supplier of critical systems, and a discussion of project challenges, especially those dealing with the following items:accommodation of a broad experimental domain; involvement by international partners making in-kind contributions to the project; ? development of components critical to safety and performance; the revival of engineering of research reactors and experimental devices involving France's historical players in the field of research reactors, and; tools to carry out the project, including computer codes

Biological biogas upgrading capacity of a hydrogenotrophic community in a trickle-bed reactor

International Nuclear Information System (INIS)

Rachbauer, Lydia; Voitl, Gregor; Bochmann, Günther; Fuchs, Werner

2016-01-01

Highlights: • Data on long term operation of a system supplied with real biogas are presented. • Ex-situ biological methanation is feasible for biogas upgrading. • Gas quality obtained complies with strictest direct grid injection criteria. • Biomethane can act as flexible storage for renewable surplus electricity. - Abstract: The current study reports on biological biogas upgrading by means of hydrogen addition to obtain biomethane. A mesophilic (37 °C) 0.058 m"3 trickle-bed reactor with an immobilized hydrogenotrophic enrichment culture was operated for a period of 8 months using a substrate mix of molecular hydrogen (H_2) and biogas (36–42% CO_2). Complete CO_2 conversion (> 96%) was achieved up to a H_2 loading rate of 6.5 m_n"3 H_2/m"3_r_e_a_c_t_o_r _v_o_l_. × d, corresponding to 2.3 h gas retention time. The optimum H_2/CO_2 ratio was determined to be between 3.67 and 4.15. CH_4 concentrations above 96% were achieved with less than 0.1% residual H_2. This gas quality complies even with tightest standards for grid injection without the need for additional CO_2 removal. If less rigid standards must be fulfilled H_2 loading rates can be almost doubled (10.95 versus 6.5 m_n"3 H_2/m"3_r_e_a_c_t_o_r _v_o_l_. × d) making the process even more attractive. At this H_2 loading the achieved methane productivity was 2.52 m_n"3 CH_4/m"3_r_e_a_c_t_o_r _v_o_l_. × d. In terms of biogas this corresponds to an upgrading capacity of 6.9 m_n"3 biogas/m"3_r_e_a_c_t_o_r _v_o_l_. × d. The conducted experiments demonstrate that biological methanation in an external reactor is well feasible for biogas upgrading under the prerequisite that an adequate H_2 source is available.

Modernized accurate methods for processing of in-core measurement signals in WWER reactors

International Nuclear Information System (INIS)

Polak, T.

1996-01-01

Utilization of the new accurate WIMS-KAERI library (WIMKAL-88) to generate the following characteristics for Rhodium SPND: Sensitivity depletion law by high (approx= 75%) burnup of emitter; influence of burnup-history on depletion law course; influence of neutron spectrum change on Rh-SPND sensitivity caused by change of fuel enrichment, fuel burnup, moderator temperature, concentration of boracid, central pin power rate and concentration of Xe 135 ; generating and experimental testing of Rh-SPND signal to linear pin power rate and signal to neutron flux conversion factors. Rh-SPND instrumentation optimization (reduction) related to safety and operational aspects as needed for 3D power surveillance in WWER-1000 reactors. Analysis of SPND reduction from 64x7 to 46x7 by method of Shannon information entropy optimization. Influence of reduction on accuracy of 3D power distribution reconstruction. Physical methods of 3D power distribution unfolding in new modernized on-line I and C system in NPP J. Bohunice with in-core measurements according to 210 thermocouples and 36x7 Rh-SPNDs. Program system TOPRE under QNX operating system network in FORTRAN 77, neutronic background calculations by macrocode MOBY-DICK. (author). 10 refs, 6 figs, 7 tabs

TMI-2 reactor vessel head removal

International Nuclear Information System (INIS)

Bengel, P.R.; Smith, M.D.; Estabrook, G.A.

1985-09-01

This report describes the safe removal and storage of the Three Mile Island Unit 2 (TMI-2) reactor vessel head. The head was removed in July 1984 to permit the removal of the plenum and the reactor core, which were damaged during the 1979 accident. From July 1982, plans and preparations were made using a standard head removal procedure modified by the necessary precautions and changes to account for conditions caused by the accident. After data acquisition, equipment and structure modifications, and training, the head was safely removed and stored; and the internals indexing fixture and a work platform were installed on top of the vessel. Dose rates during and after the operation were lower than expected; lessons were learned from the operation which will be applied to the continuing fuel removal operations activities

TMI-2 reactor vessel plenum final lift

International Nuclear Information System (INIS)

Wilson, D.C.

1986-01-01

Removal of the plenum assembly from the TMI-2 reactor vessel was necessary to gain access to the core region for defueling. The plenum was lifted from the reactor vessel by the polar crane using three specially designed pendant assemblies. It was then transferred in air to the flooded deep end of the refueling canal and lowered onto a storage stand where it will remain throughout the defueling effort. The lift and transfer were successfully accomplished on May 15, 1985 in just under three hours by a lift team located in a shielded area within the reactor building. The success of the program is attributed to extensive mockup and training activities plus thorough preparations to address potential problems. 54 refs

Activities in the Czech Republic for reactor pressure components lifetime management

International Nuclear Information System (INIS)

Brumovsky, M.

1994-01-01

The following activities in the Czech republic for reactor pressure components lifetime management are described: upgrading and safety assurance of nuclear power plants (NPP) with reactors of WWER-440/V-230 type, safety assurance of NPPs with reactors of WWER-440/V-213, lifetime management programme of NPPs with WWER-440/V-213 reactors, preparation of start-up of NPPs with WWER-1000/V-320 reactors, preparation of guides for lifetime as well as defect allowability evaluation in main components of primary and secondary circuits. 3 figs

Current and future possibilities of V2V and I2V technologies: an analysis directed toward Augmented Reality systems

Science.gov (United States)

Betancur, J. A.; Osorio-Gómez, Gilberto; Arnedo, Aida; Yarce Botero, Andrés.

2014-06-01

Nowadays, it is very important to explore the qualitative characteristics of autonomous mobility systems in automobiles, especially disruptive technology like Vehicle to Vehicle (V2V) and Infrastructure to Vehicle (I2V), in order to comprehend how the next generation of automobiles will be developed. In this sense, this research covers a general review about active safety in automobiles where V2V and I2V systems have been implemented; identifying the more realistic possibilities related to V2V and I2V technology and analyzing the current applications, some systems in development process and some future conceptual proposals. Mainly, it is notorious the potential development of mixing V2V and I2V systems pointing to increase the driver's attention; therefore, a configuration between these two technologies and some augmented reality system for automobiles (Head-Up Display and Head-Down Display) is proposed. There is a huge potential of implementation for this kind of configuration once the normative and the roadmap for its development can be widely established.

Operational inspections

International Nuclear Information System (INIS)

Bystersky, M.

1997-01-01

Special equipment is described, designed for inspection of reactor pressure vessels performed from the inside. Central shaft manipulator ZMM-5 is available for crack detection control using ultrasound and eddy currents, for visual check of surfaces, repair works at the reactor pressure vessel, and hardness measurements. The manipulator consists of the manipulator bridge, a cable container, shaft segments, a control mechanism and auxiliary parts. Eight inspections were performed at the Bohunice nuclear power plant and two at the Paks nuclear power plant. (M.D.)

Refurbishment programme for the BR2-reactor

Energy Technology Data Exchange (ETDEWEB)

Koonen, E [Centre d' Etude de l' Energie Nucleaire, Studiecentrum voor Kernenergie, BR2 Department, Boeretang, Mol (Belgium)

1992-07-01

BR2 is a high flux engineering test reactor, which differs from comparable material testing reactors by its specific core array (fig. 1). It is a heterogeneous, thermal, tank-in-pool type reactor, moderated by beryllium and light water, which serves also as coolant. The fuel elements consist of cylindrical assemblies loaded in channels materialized by hexagonal beryllium prisms. The central 200 mm channel is vertical, while all others are inclined and form a hyperbolical arrangement around the central one. This feature combines a very compact core with the requirement of sufficient space for individual access to all channels through penetrations in the top cover of the aluminium pressure vessel. Each channel may hold a fuel element, a control rod, an experiment, an irradiation device or a beryllium plug. The refurbishment Program According to the present programme of C.E.N./S.C.K., BR2 will be in operation until 1996. At that time, the beryllium matrix will reach its foreseen end-of-life. In order to continue operation beyond this point, a thorough refurbishment of the reactor is foreseen, in addition to the unavoidable replacement of the matrix, to ensure quality of the installation and compliance with modern standards. Some fundamental options have been taken as a starting point: BR2 will continue to be used as a classical MTR, i.e. fuel and material irradiations and safety experiments with some additional service-activities. The present configuration is optimized for that use and there is no specific experimental requirement to change the basic concepts and performance characteristics. From the customers viewpoint, it is desirable to go ahead with the well-known features of BR2, to maintain a high degree of availability and reliability and to minimize the duration of the long shutdown. It is also important to limit the amount of nuclear liabilities. So the objective of the refurbishment programme is the life extension of BR2 for about 15 years, corresponding to

Refurbishment programme for the BR2-reactor

International Nuclear Information System (INIS)

Koonen, E.

1992-01-01

BR2 is a high flux engineering test reactor, which differs from comparable material testing reactors by its specific core array (fig. 1). It is a heterogeneous, thermal, tank-in-pool type reactor, moderated by beryllium and light water, which serves also as coolant. The fuel elements consist of cylindrical assemblies loaded in channels materialized by hexagonal beryllium prisms. The central 200 mm channel is vertical, while all others are inclined and form a hyperbolical arrangement around the central one. This feature combines a very compact core with the requirement of sufficient space for individual access to all channels through penetrations in the top cover of the aluminium pressure vessel. Each channel may hold a fuel element, a control rod, an experiment, an irradiation device or a beryllium plug. The refurbishment Program According to the present programme of C.E.N./S.C.K., BR2 will be in operation until 1996. At that time, the beryllium matrix will reach its foreseen end-of-life. In order to continue operation beyond this point, a thorough refurbishment of the reactor is foreseen, in addition to the unavoidable replacement of the matrix, to ensure quality of the installation and compliance with modern standards. Some fundamental options have been taken as a starting point: BR2 will continue to be used as a classical MTR, i.e. fuel and material irradiations and safety experiments with some additional service-activities. The present configuration is optimized for that use and there is no specific experimental requirement to change the basic concepts and performance characteristics. From the customers viewpoint, it is desirable to go ahead with the well-known features of BR2, to maintain a high degree of availability and reliability and to minimize the duration of the long shutdown. It is also important to limit the amount of nuclear liabilities. So the objective of the refurbishment programme is the life extension of BR2 for about 15 years, corresponding to

Early detection and identification of anomalies in chemical regime based on computational intelligence techniques

International Nuclear Information System (INIS)

Figedy, Stefan; Smiesko, Ivan

2012-01-01

This article provides brief information about the fundamental features of a newly-developed diagnostic system for early detection and identification of anomalies being generated in water chemistry regime of the primary and secondary circuit of the VVER-440 reactor. This system, which is called SACHER (System of Analysis of CHEmical Regime), was installed within the major modernization project at the NPP-V2 Bohunice in the Slovak Republic. The SACHER system has been fully developed on MATLAB environment. It is based on computational intelligence techniques and inserts various elements of intelligent data processing modules for clustering, diagnosing, future prediction, signal validation, etc, into the overall chemical information system. The application of SACHER would essentially assist chemists to identify the current situation regarding anomalies being generated in the primary and secondary circuit water chemistry. This system is to be used for diagnostics and data handling, however it is not intended to fully replace the presence of experienced chemists to decide upon corrective actions. (author)

Operational report, basics of the preliminary project for reconstruction of the RA reactor ventilation system

International Nuclear Information System (INIS)

Martinc, R.

1982-01-01

This report presents the summary of results needed for designing the reconstruction of the RA reactor ventilation system. The final complete report will published later, including results of possible additional analyses according to the needs of main detailed project. Due to the size of the facility the need of filters for particulates is expected in systems V-1 and V-2, as well as revision of the system V-4. Adsorption filters are not needed in case of operation under regular working conditions. It would be favorable, but not indispensable to construct an adsorption filter that could be used occasionally at the input of V-2 system under the upper water shielding. This filter would be switched on when dehermetization of the reactor is planned and increased radioactivity is indicated in the gas system or experimental space of the RA reactor as well as in case of fuel elements failure. The aim of applying filters is shortening the time these elements would spend in the hermetized reactor i.e. their fast removal from the reactor. It is indispensable to build-in 'emergency' highly efficient adsorption filters in the V-2 system which would be switched on in case of accidents that would cause fuel elements meltdown (with simultaneous accident dehermetization of the heavy water system) [sr

The ICRH tokamak fusion test reactor

International Nuclear Information System (INIS)

Perkins, F.W.

1976-01-01

A Tokamak Fusion Test Reactor where the ion are maintained at Tsub(i) approximately 20keV>Tsub(e) approximately 7keV by ion-cyclotron resonance heating is shown to produce an energy amplification of Q>2 provided the principal ion energy loss channel is via collisional transfer to the electrons. Such a reactor produces 19MW of fusion power to the electrons. Such a reactor produces 19MW of fusion power and requires a 50MHz radio-frequency generator capable of 50MW peak power; it is otherwise compatible with the conceptual design for the Princeton TFTR. The required n tausub(E) values for electrons and ions are respectively ntausub(Ee)>1.5.10 13 cm -3 -sec and ntausub(Ei)>4.10 13 cm -3 -sec. The principal areas where research is needed to establish this concept are: tokamak transport calculations, ICRH physics, trapped-particle instability energy losses, tokamak equilibria with high values of βsub(theta), and, of course, impurities

X-ray digital industrial radiography (DIR) for local liquid velocity (V{sub LL}) measurement in trickle bed reactors (TBRs): Validation of the technique

Energy Technology Data Exchange (ETDEWEB)

Mohd Salleh, Khairul Anuar, E-mail: kmfgf@mst.edu; Lee, Hyoung Koo [Department of Mining and Nuclear Engineering, Missouri University of Science and Technology, Fulton Hall, 310 W. 14th St., Rolla, Missouri 65409 (United States); Rahman, Mohd Fitri Abdul [Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology, 143 Schrenk Hall, 400 W. 11th St., Rolla, Missouri 65409 (United States); Al Dahhan, Muthanna H. [Department of Mining and Nuclear Engineering, Missouri University of Science and Technology, Fulton Hall, 310 W. 14th St., Rolla, Missouri 65409 (United States); Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology, 143 Schrenk Hall, 400 W. 11th St., Rolla, Missouri 65409 (United States)

2014-06-15

Local liquid velocity measurements in Trickle Bed Reactors (TBRs) are one of the essential components in its hydrodynamic studies. These measurements are used to effectively determine a reactor's operating condition. This study was conducted to validate a newly developed technique that combines Digital Industrial Radiography (DIR) with Particle Tracking Velocimetry (PTV) to measure the Local Liquid Velocity (V{sub LL}) inside TBRs. Three millimeter-sized Expanded Polystyrene (EPS) beads were used as packing material. Three validation procedures were designed to test the newly developed technique. All procedures and statistical approaches provided strong evidence that the technique can be used to measure the V{sub LL} within TBRs.

Refurbishing the BR2 materials testing reactor

International Nuclear Information System (INIS)

Baugnet, J.M.; Dekeyser, J.; Gubel, P.

1995-01-01

SCK/CEN is refurbishing its BR2 reactor to allow its further operation during the next 15 years; in doing so, it chooses to keep BR2 available for future scientific and technological irradiation programs within an international context. (author) 2 figs

Analysis of the ZPPR-15 Critical Experiments with ENDF/B-V.2 and ENDF/B-VII.0 Data

International Nuclear Information System (INIS)

Kim, Sang Ji; Yang, Won Sik; Lee, Changho

2008-01-01

This paper presents the analysis results for the ZPPR-15 critical experiments. Using the ENDF/B-V.2 and ENDF/B-VII.0 data, three loading configurations of the ZPPR-15 Phase A experiments were analyzed with the ANL code suite for a fast reactor neutronics analysis, including the recently updated MC 2 -2 code. For the VIM Monte Carlo analyses with 3-D as-built models, the ENDF/B-VII.0 data improved the core multiplication factors by 0.21 to 0.37 %Δk, relative to the ENDF/B-V.2 data. With the plate heterogeneity effects taken into account by the SDX 1-D unit cell calculations, the DIF3D nodal transport solutions with the ENDF/B-V.2 data showed a good agreement for the core multiplication factors with the VIM Monte Carlo results to within 0.12 %Δk, but those with the ENDF/B-VII.0 data showed relatively larger deviations. Sensitivity studies based on the RZ models with homogenized cells showed excellent agreement for the core multiplication factors between the deterministic and Monte Carlo calculations to within 0.1 %Δk for both ENDF/B data. These results indicate that the MC 2 -2 methods are adequate for generating the multigroup cross sections for a fast reactor analysis, but the SDX process to account for the heterogeneity effect needs to be improved for the ENDF/B-VII.0 data. (authors)

Proceedings of 2. Yugoslav symposium on reactor physics, Part 2, Herceg Novi (Yugoslavia), 27-29 Sep 1966

International Nuclear Information System (INIS)

1966-01-01

This Volume 2 of the Proceedings of 2. Yugoslav symposium on reactor physics includes eight papers dealing with the following topics: method for measuring high anti reactivities of a reactor system; integration method for thermal reaction rate calculation; Determination of initial core configuration for BHWR-200 MWe; safety shutdowns and failures of the RA reactor equipment; determining the reactivity of absorption rods; measurements of thermal and fast neutron fluxes at the TRIGA reactor and other measurements during operation of the TRIGA reactor; mathematical modelling of the reactor safety; review of problems and methods for radiation risk assessment in the environment of a nuclear power plant

SIRIUS 2: A versatile medium power research reactor

International Nuclear Information System (INIS)

Rousselle, P.

1992-01-01

Most of the Research Reactors in the world have been critical in the Sixties and operated for twenty to thirty years. Some of them have been completely shut down, modified, or simply refurbished; the total number of RR in operation has decreased but there is still an important need for medium power research reactors in order: - to sustain a power program with fuel and material testing for NPP or fusion reactors; - to produce radioisotopes for industrial or medical purposes, doped silicon, NAA or neutron radiography; - to investigate further the condensed matter, with cold neutrons routed through neutron guides to improved equipment; - to develop new technologies and applications such as medical alphatherapy. Hence, taking advantage of nearly hundred reactor x years operation and backed up by the CEA experience, TECHNICATOME assisted by FRAMATOME has designed a new versatile multipurpose Research Reactor (20-30 Mw) SIRIUS 2 taking into account: - more stringent safety rules; - the lifetime; - the flexibility enabling a wide range of experiments and, - the future dismantling of the facility according to the ALARA criteria

On the anisotropy of in-reactor creep of Zr-2.5Nb tubes

International Nuclear Information System (INIS)

Causey, A.R.; Holt, R.A.

1993-06-01

Creep specimens made from cold-worked Zr-2.5Nb tubes, fabricated with two different microstructures and crystallographic textures, were irradiated in the Osiris reactor in France in a fast-neutron flux of about 1.8 x 10 18 n.m -2 .s -1 , E > MeV, at 553 and 585 K. The hoop stresses from internal Fluences, up to 4 x 10 25 n.m -2 , more than double those achieved an any other creep test on cold-worked Zr-2.5Nb in which both axial and transverse strain were measured. Creep rates were obtained from strain versus fluence plots, and creep compliances were obtained from plots of the strain rates against hoop stress for each material at each temperature. The ratio of creep rates at 583 K to those at 553 K was ∼ 1.36, a little higher than that extrapolated from stress relaxation results at temperatures between 523 and 568 K. The ratio of the biaxial creep compliance in the axial direction to that in the transverse directions is different for the two test materials: 0.0 to -0.1 for the fuel sheathing texture and 0.5 to 0.6 for the pressure tube texture. The results were analysed using a self-consistent model developed to account for the contributions to the creep anisotropy of the three microstructure parameters involved and to account for the grain interaction effects. The model, which was normalized to test reactor and power reactor creep data for cold-worked Zr-2.5Nb tubes, predicted the ratio of the creep compliancies to be -0.26 and 0.63, respectively. Thus the creep anisotropy of Zr-2.5Nb tubes with pressure-tube-like crystallographic texture can be adequately predicted. (author). 18 refs., 4 tabs., 13 figs

Comparison of Planning, Management and Organizational Aspects of Nuclear Power Plants A1 and V1 Decommissioning

Energy Technology Data Exchange (ETDEWEB)

Stubna, M.; Michal, V., E-mail: Marian.Stubna@vuje.sk, E-mail: V.Michal@iaea.org [VUJE, Inc. Trnava (Slovakia); Daniska, V., E-mail: Daniska@decom.sk [DECOM, Inc. Trnava (Slovakia); Sirota, J., E-mail: Sirota.Jan@javys.sk [JAVYS, Inc. Bratislava, (Slovakia)

2013-08-15

This contribution deals with planning, management and organizational aspects of decommissioning of NPP shut down due to the accident (prototype NPP A1) and NPP shut down after normal operation (NPP V1). The A1 and V1 NPPs are located very close in Bohunice nuclear site however both plants have very different technology and operational history. The preparation of A1 NPP decommissioning strategy and relevant decommissioning plans was long term process, because the plant was shut down after the accident in 1977 and decommissioning was implemented first time in Slovakia with many specific difficulties. The decommissioning planning of V1 NPP was shorter and easier, because the plant was shut down after normal operation, there were lessons learned from the A1 NPP decommissioning planning, available legislation, available financing etc. Development of decommissioning strategies, preparation and planning for decommissioning, development of legislation for decommissioning, management of decommissioning projects and other aspects are described and compared. Lessons learned are formulated on the basis of analysis of past, ongoing and planned decommissioning activities in Slovakia. (author)

Improvement of operational performance and increase of safety of WWER-1000/V-392

International Nuclear Information System (INIS)

Kurakov, Y.A.; Dragunov, Y.G.; Podshibiakin, A.K.; Fil, N.S.; Krushelnitsky, V.N.; Berkovich, V.M.

2001-01-01

The national programme of nuclear power development approved by the Russian Federation Government in 1998 considers the design of WWER-1000/V-392 power unit as a priority project of the new generation NPP with improved operational performances and increased safety. The pilot unit of this design (NVAES-2) is licensed for construction at the Novovoronezh NPP site. The NVAES-2 design is developed on the basis of standard power unit with reactor plant V-320. Twenty units of this type are in operation at the nuclear power plants in Russia, Ukraine and Bulgaria having totally about 270 reactor-years of operation. Two more V-320 units are being commissioned this year at Rostov NPP and Temelin NPP. So, the WWER-1000/V-392 design is as a whole an evolutionary development of the operating standard unit WWER-1000/V-320. Many technical solutions aimed at increase of safety and improvement of operational performance of the plant are implemented in the NVAES-2 design, such as advanced reactor WWER-1000, passive system of residual power removal, passive system of the core flooding under loss-of-coolant accidents, and others. NVAES-2 design refers to a class of advanced light water reactors and corresponds to the international requirements imposed to the nuclear power plants to be put into operation after the year 2000. New V-392 power unit has a good perspective from the view point of extensive implementation in the framework of the nuclear electricity production in Russia. Design decisions on NVAES-2 power unit with WWER-1000/V-392 reactor plant which assure significantly higher safety level and improve economical performance as compared to the operating WWER-1000 units are briefly considered in the present paper. (author)

Report of the ASSET (Assessment of Safety Significant Events Team) follow-up mission to the Bohunice (units 1-2) nuclear power plant in Slovakia 5-9 July 1993. Root cause analysis of operational events with a view to enhancing the prevention of accidents

International Nuclear Information System (INIS)

1993-01-01

This Report of the IAEA Assessment of Safety Significant Events Team (ASSET) presents the results of the team's review of the status of implementation of the recommendations made by the 1988 ASSET mission to Bohunice nuclear power plant in Slovakia, and of progress made by plant management in prevention of incidents. The findings, conclusions and suggestions presented herein reflect the views of the ASSET experts. They are provided for consideration by the responsible Slovakian authorities. The ASSET team's views presented in this report are based on review of the documentation made available and on the discussions with plant staff. The report includes the official response of the operating and regulatory organizations of Slovakia to the ASSET findings and conclusions. Figs, tabs

Theoretical analysis of nuclear reactors (Phase I), I-V, Part V, Determining the fine flux distribution; Razrada metoda teorijske analize nuklearnih reaktora (I faza) I-V, V Deo, Odredjivanje fine raspodele fluksa

Energy Technology Data Exchange (ETDEWEB)

Pop-Jordanov, J [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Serbia and Montenegro)

1962-07-15

Mono energetic neutron transport equation was solved by Carlson numerical method in cylindrical geometry. S{sub n} code was developed for the digital computer ZUSE Z23. Neutron flux distribution was determined for the RA reactor cell by applying S{sub 4} approximation. Reactor cell was treated as D{sub 2}O-U-D{sub 2}O system. Time of iteration was 185 s. Resena je transportna monoenergetska jednacina numerickom metodom Carlsona u cilindricnoj geometriji. Razvijanje S{sub n} kod za digitalnu masinu ZUSE-Z 23. Odredjena je raspodela fluksa u celiji reaktora RA S{sub 4} aproksimacijom. Celija je tretirana kao D{sub 2}O-U-D{sub 2}O. Vreme iteracije je 185 sec (author)

OTUS - Reactor inventory management system based on ORIGEN2

Energy Technology Data Exchange (ETDEWEB)

Poellaenen, R; Toivonen, H; Lahtinen, J; Ilander, T

1995-10-01

ORIGEN2 is a computer code that calculates nuclide composition and other characteristics of nuclear fuel. The use of ORIGEN2 requires good knowledge in reactor physics. However, once the input has been defined for a particular reactor type, the calculations can be easily repeated for any burnup and decay time. This procedure produces large output files that are difficult to handle manually. A new computer code, known as OTUS, was designed to facilitate the postprocessing of the data. OTUS makes use of the inventory files precalculated with ORIGEN2 in a way that enables their versatile treatment for different safety analysis purposes. A data base is created containing a comprehensive set of ORIGEN2 calculations as a function of fuel burnup and decay time. OTUS is a reactor inventory management system for a microcomputer with Windows interface. Four major data operations are available: (1) Build data modifies ORIGEN2 output data into a suitable format, (2) View data enables flexible presentation of the data as such, (3) Different calculations, such as nuclide ratios and hot particle characteristics, can be performed for severe accident analyses, consequence analyses and research purposes, (4) Summary files contain both burnup dependent and decay time dependent inventory information related to the nuclide and the reactor specified. These files can be used for safeguards, radiation monitoring and safety assessment. (orig.) (22 refs., 29 figs.).

The 2nd reactor core of the NS Otto Hahn

International Nuclear Information System (INIS)

Manthey, H.J.; Kracht, H.

1979-01-01

Details of the design of the 2nd reactor core are given, followed by a brief report summarising the operating experience gained with this 2nd core, as well as by an evaluation of measured data and statements concerning the usefulness of the knowledge gained for the development of future reactor cores. Quite a number of these data have been used to improve the concept and thus the specifications for the fuel elements of the 3rd core of the reactor of the NS Otto Hahn. (orig./HP) [de

Reactor Dosimetry State of the Art 2008

Science.gov (United States)

Voorbraak, Wim; Debarberis, Luigi; D'Hondt, Pierre; Wagemans, Jan

2009-08-01

. Williams, A. P. Ribaric and T. Schnauber. Agile high-fidelity MCNP model development techniques for rapid mechanical design iteration / J. A. Kulesza.Extension of Raptor-M3G to r-8-z geometry for use in reactor dosimetry applications / M. A. Hunter, G. Longoni and S. L. Anderson. In vessel exposure distributions evaluated with MCNP5 for Atucha II / J. M. Longhino, H. Blaumann and G. Zamonsky. Atucha I nuclear power plant azimutal ex-vessel flux profile evaluation / J. M. Longhino ... [et al.]. UFTR thermal column characterization and redesign for maximized thermal flux / C. Polit and A. Haghighat. Activation counter using liquid light-guide for dosimetry of neutron burst / M. Hayashi ... [et al.]. Control rod reactivity curves for the annular core research reactor / K. R. DePriest ... [et al.]. Specification of irradiation conditions in VVER-440 surveillance positions / V. Kochkin ... [et al.]. Simulations of Mg-Ar ionisation and TE-TE ionisation chambers with MCNPX in a straightforward gamma and beta irradiation field / S. Nievaart ... [et al.]. The change of austenitic stainless steel elements content in the inner parts of VVER-440 reactor during operation / V. Smutný, J. Hep and P. Novosad. Fast neutron environmental spectrometry using disk activation / G. Lövestam ... [et al.]. Optimization of the neutron activation detector location scheme for VVER-lOOO ex-vessel dosimetry / V. N. Bukanov ... [et al.]. Irradiation conditions for surveillance specimens located into plane containers installed in the WWER-lOOO reactor of unit 2 of the South-Ukrainian NPP / O. V. Grytsenko. V. N. Bukanov and S. M. Pugach. Conformity between LRO mock-ups and VVERS NPP RPV neutron flux attenuation / S. Belousov. Kr. Ilieva and D. Kirilova. FLUOLE: a new relevant experiment for PWR pressure vessel surveillance / D. Beretz ... [et al.]. Transport of neutrons and photons through the iron and water layers / M. J. Kost'ál ... [et al.]. Condition evaluation of spent nuclear fuel assemblies

The influence of Triga 2000 reactor operation on the surface contamination at reactor room using smear test method

International Nuclear Information System (INIS)

Bintu Khoiriyyah; Budi Purnama; Tri Cahyo Laksono

2016-01-01

The monitoring of surface contamination should be conducted to determine the safety of work areas. Surface contamination at the TRIGA 2000 reactor room which is on PSTNT-BATAN Bandung remain to be implemented although reactor not operating. In this research monitoring of surface contamination when TRIGA 2000 in operation of the first time after several years not operating aims to determine the influence on the results of monitoring. The monitoring of surface contamination has been done using smear test method at some predetermined in TRIGA 2000 reactor room. The highest surface contamination activities is obtained 0.32 Bq/cm 2 and there are some points that are not detected. Based on keputusan kepala BAPETEN No.1/Ka BAPETEN/ V/99 the work showed that the TRIGA 2000 reactor in the category of low area contamination, that is <3.7 Bq/cm 2 to gross beta. (author)

Mirror reactor studies

International Nuclear Information System (INIS)

Moir, R.W.; Barr, W.L.; Bender, D.J.

1977-01-01

Design studies of a fusion mirror reactor, a fusion-fission mirror reactor, and two small mirror reactors are summarized. The fusion reactor uses 150-keV neutral-beam injectors based on the acceleration of negative ions. The injectors provide over 1 GW of continuous power at an efficiency greater than 80%. The fusion reactor has three-stage, modularized, Venetian blind, plasma direct converter with a predicted efficiency of 59% and a new concept for removal of the lune-shaped blanket: a crane is brought between the two halves of the Yin-Yang magnet, which are separated by a float. The design has desirable features such as steady-state operation, minimal impurity problems, and low first-wall thermal stress. The major disadvantage is low Q resulting in high re-circulating power and hence high cost of electrical power. However, the direct capital cost per unit of gross electrical power is reasonable [$1000/kW(e)]. By contrast, the fusion-fission reactor design is not penalized by re-circulating power and uses relatively near-term fusion technology being developed for the fusion power program. New results are presented on the Th- 233 U and the U- 239 Pu fuel cycles. The purpose of this hybrid is fuel production, with projected costs at $55/g of Pu or $127/g of 233 U. Blanket and cooling system designs, including an emergency cooling system, by General Atomic Company, lead us to the opinion that the reactor can meet expected safety standards for licensing. The smallest mirror reactor having only a shield between the plasma and the coil is the 4.2-m long fusion engineering research facility (FERF) designed for material irradiation. The smallest mirror reactor having both a blanket and shield is the 7.5-m long experimental power reactor (EPR), which has both a fusion and a fusion-fission version. (author)

Fission product release from UO2 during irradiation. Diffusion data and their application to reactor fuel pins

International Nuclear Information System (INIS)

Findlay, J.R.; Johnson, F.A.; Turnbull, J.A.; Friskney, C.A.

1980-01-01

Release of fission product species from UO 2 , and to a limited extent from (U, Pu)0 2 was studied using small scale in-reactor experiments in which these interacting variables may be separated, as far as is possible, and their influences assessed. Experiments were at fuel ratings appropriate to water reactor fuel elements and both single crystal and poly-crystalline specimens were used. They employed highly enriched uranium such that the relative number of fissions occurring in plutonium formed by neutron capture was small. The surface to volume ratio (S/V) of the specimens was well defined thus reducing the uncertainties in the derivation of diffusion coefficients. These experiments demonstrate many of the important characteristics of fission product behaviour in UO 2 during irradiation. The samples used for these experiments were small being always less than 1g with a fissile content usually between 2 and 5mg. Polycrystalline materials were taken from batches of production fuel prepared by conventional pressing and sintering techniques. The enriched single crystals were grown from a melt of sodium and potassium chloride doped with UO 2 powder 20% 235 U content. The irradiations were performed in the DIDO reactor at Harwell. The neutron flux at the specimen was 4x10 16 neutrons m -2 s -1 providing a heat rating within the samples of 34.5 MW/teU

Design project of the dosimetry control system in the independent CO2 loop for cooling the samples irradiated in the RA reactor vertical experimental channels, Vol. V

International Nuclear Information System (INIS)

1964-01-01

Design project of the dosimetry control system in the independent CO 2 loop for cooling the samples irradiated in the RA reactor vertical experimental channels includes the following: calculations of CO 2 gas activity, design of the dosimetry control system, review of the changes that should be done in the RA reactor building for installing the independent CO 2 loop, specification of the materials with cost estimation, engineering drawings of the system [sr

Sequential injection spectrophotometric determination of V(V) in ...

African Journals Online (AJOL)

2009-01-15

Jan 15, 2009 ... The determination was based on the oxidation of dopamine (DP) by V(V) in acidic medium followed by ... To overcome some of these drawbacks some flow injec- ..... The analytical signal increased with the reactor length.

EL-2 reactor: Thermal neutron flux distribution

International Nuclear Information System (INIS)

Rousseau, A.; Genthon, J.P.

1958-01-01

The flux distribution of thermal neutrons in EL-2 reactor is studied. The reactor core and lattices are described as well as the experimental reactor facilities, in particular, the experimental channels and special facilities. The measurement shows that the thermal neutron flux increases in the central channel when enriched uranium is used in place of natural uranium. However the thermal neutron flux is not perturbed in the other reactor channels by the fuel modification. The macroscopic flux distribution is measured according the radial positioning of fuel rods. The longitudinal neutron flux distribution in a fuel rod is also measured and shows no difference between enriched and natural uranium fuel rods. In addition, measurements of the flux distribution have been effectuated for rods containing other material as steel or aluminium. The neutron flux distribution is also studied in all the experimental channels as well as in the thermal column. The determination of the distribution of the thermal neutron flux in all experimental facilities, the thermal column and the fuel channels has been made with a heavy water level of 1825 mm and is given for an operating power of 1000 kW. (M.P.)

Physics design of advanced steady-state tokamak reactor A-SSTR2

International Nuclear Information System (INIS)

Nishio, Satoshi; Ushigusa, Kenkichi

2000-10-01

Based on design studies on the fusion power reactor such as the DEMO reactor SSTR, the compact power reactor A-SSTR and the DREAM reactor with a high environmental safety and high availability, a new concept of compact and economic fusion power reactor (A-SSTR2) with high safety and high availability is proposed. Employing high temperature superconductor, the toroidal filed coils supplies the maximum field of 23T on conductor which corresponds to 11T at the magnetic axis. A-SSTR2 (R p =6.2m, a p =1.5m, I p =12MA) has a fusion power of 4GW with β N =4. For an easy maintenance and for an enough support against a strong electromagnetic force on coils, a poloidal coils system has no center solenoid coils and consists of 6 coils located on top and bottom of the machine. Physics studies on the plasma equilibrium, controllability of the configuration, the plasma initiation and non-inductive current ramp-up, fusion power controllability and the diverter have shown the validity of the A-SSTR2 concept. (author)

Management of the Bohunice RPVs annealing procedures

International Nuclear Information System (INIS)

Repka, M.

1994-01-01

The program of annealing regeneration procedure of RPVs units 1 and 2 of NPP V-1 (EBO) realization in the year 1993, is the topic of this paper. In the paper the following steps are described in detail: the preparation works, the annealing procedure realization schedule and safety management: starting with zero conditions, assembling of annealing apparatus, annealing procedure, cooling down and disassembling procedure of annealing apparatus. At the end the programs of annealing of both RPVs including the dosimetry measurements are discussed and evaluated. (author). 3 figs

FORE-2, Thermohydraulics and Space-Independent Reactor Kinetics for Transients

International Nuclear Information System (INIS)

Fox, J.N.; Lawler, B.E.; Butz, H.R.; Heames, T.J.

1984-01-01

1 - Description of problem or function: FORE2 is a coupled thermal hydraulics-point kinetics digital computer code designed to calculate significant reactor parameters under steady-state conditions, or as functions of time during transients. The transients may result from a programmed reactivity insertion or a power change. Variable inlet coolant flow rate and temperature are considered. The code calculates the reactor power, the individual reactivity feedbacks, and the temperature of coolant, cladding, fuel, structure, and additional material for up to seven axial positions in three channel types which represent radial zones of the reactor. The heat of fusion, accompanying fuel melting, the liquid metal voiding reactivity, and the spatial and the time variation of the fuel cladding gap coefficient due to changes in gap size are considered. 2 - Method of solution: FORE2 input consists of property data, geometry, power and flow distribution factors, external time varying functions, experimental coefficients, and termination data. The differential equations for fluid flow, heat transfer, and point neutronics are solved by explicit finite-difference procedures. 3 - Restrictions on the complexity of the problem: Reactor excursions which can be calculated are restricted to those transients in which the reactor is not substantially destroyed. As a general rule, changes in reactor geometry and composition during an excursion are limited to those cases in which the reactivity effects of the changes may be considered as small perturbations of the initial system. Thus, accidents involving large-scale disassembly and bulk meltdown of a core are not covered by FORE2. FORE2 is valid only while the core retains its initial geometry

Mathematical simulation of gas pressure in fibre-reinforced concrete container at radiation and biological decomposition of cellulose, bituminized and concrete radwastes

International Nuclear Information System (INIS)

Kuruc, J.; Kvito, P.

2005-01-01

Fibre-reinforced concrete container (FRCC) are used for long-time repository of radioactive wastes. Low- and middle-active radwastes from operation of the NPPs V-1, V-2 Jaslovske Bohunice, Mochovce NPP and from decommissioned NPP A-1 (Jaslovske Bohunice) are treated in the plant SE-VYZ in Jaslovske Bohunice and after immobilisation are deposited in National Radwaste Repository Mochovce (RU RAO). After filling of the RU RAO, FRCC will be stored during 300 years. During this time the integrity of the FRCC must be guaranteed. By the influence of autoradiolysis of the cellulose and bituminized radwastes as well as in cement grout the gases are formed, mainly the hydrogen, methane and carbon dioxide. In the case of presence of available water (a w ≥ 0.63) and in presence of microbes and moulds at appropriate conditions the biological decomposition of cellulose materials may proceed with formation of H 2 , CH 4 a CO 2 . With increasing of developed gases may increase pressure in FRCC, that may initiate the loss of integrity of the FRCC with following endangering of radiation safety of the RU RAO, respectively of the territory over the repository.Authors developed the new mathematical model of pressure of gases in FRCC and in deposited barrels with cellulose and bituminized radwastes. The mathematical model is based on biological decomposition of cellulose materials as well as on radiation decomposition of cellulose, bitumen and concrete. In this mathematical model the diffusion through the walls of FRCC is the main process responsible for decreasing of the pressure. This model was developed in two basic variants: (1) Mathematical model of gas pressure in FRCC as function of dose; (2) Mathematical model of gas pressure in FRCC as function of mass of cellulose

Fuel management of mixed reactor type power plant systems

International Nuclear Information System (INIS)

Csom, Gyula

1988-01-01

In equilibrium symbiotic power plant system containing both thermal reactors and fast breeders, excess plutonium produced by the fast breeders is used to enrich the fuel of the thermal reactors. In plutonium deficient symbiotic power plant system plutonium is supplied both by thermal plants and fast breeders. Mathematical models were constructed and different equations solved to characterize the fuel utilization of both systems if they contain only a single thermal type and a single fast type reactor. The more plutonium is produced in the system, the higher output ratio of thermal to fast reactors is achieved in equilibrium symbiotic power plant system. Mathematical equations were derived to calculate the doubling time and the breeding gain of the equilibrium symbiotic system. (V.N.) 2 figs.; 2 tabs

Innovative energy production in fusion reactors

Science.gov (United States)

Iiyoshi, A.; Momota, H.; Motojima, O.; Okamoto, M.; Sudo, S.; Tomita, Y.; Yamaguchi, S.; Ohnishi, M.; Onozuka, M.; Uenosono, C.

1993-10-01

Concepts of innovative energy production in neutron-lean fusion reactors without having the conventional turbine-type generator are proposed for improving the plant efficiency. These concepts are: (1) traveling wave direct energy conversion of 14.7 MeV protons; (2) cusp type direct energy conversion of charged particles; (3) efficient use of radiation with semiconductor and supplying clean fuel in a form of hydrogen gas; and (4) direct energy conversion from deposited heat to electric power with semiconductor utilizing Nernst effect. The candidates of reactors such as a toroidal system and an open system are also studied for application of the new concepts. The study shows the above concepts for a commercial reactor are promising.

Calculation of induced activity in the V-230 reactor

International Nuclear Information System (INIS)

Bouhahhane, A.; Farkas, G.

2013-01-01

In this paper, we focused on the calculation of the neutron induced activity of nuclear reactor components for decommissioning purposes. The results confirm, that the most important radionuclides in the reactor components dismantling process are 55 Fe (1 st decade), 60 Co (10 - 50 y) and 63 Ni (during the whole process). Another aim of this paper was to refer to the possibility to improve the accuracy of the calculations using continuous energy Monte Carlo methods. (authors)

The Jules Horowitz reactor project, a driver for revival of the research reactor community

Energy Technology Data Exchange (ETDEWEB)

Pere, P.; Cavailler, C.; Pascal, C. [AREVA TA, CEA Cadarache - Etablissement d' AREVA TA - Chantier RJH - MOE - BV2 - BP no. 9 - 13115 Saint Paul lez Durance (France); CS 50497 - 1100, rue JR Gauthier de la Lauziere, 13593 Aix en Provence cedex 3 (France)

2010-07-01

The first concrete of the nuclear island for the Jules Horowitz Reactor (JHR) was poured at the end of July 2009 and construction is ongoing. The JHR is the largest new platform for irradiation experiments supporting Generation II and III reactors, Generation IV technologies, and radioisotope production. This facility, composed of a unique grouping of workshops, hot cells and hot laboratories together with a first -rate MTR research reactor, will ensure that the process, from preparations for irradiation experiments through post-irradiation non-destructive examination, is completed expediently, efficiently and, of course, safely. In addition to the performance requirements to be met in terms of neutron fluxes on the samples (5x10{sup 14} n.cm{sup -2}/sec{sup -1} E> 1 MeV in core and 3,6x10{sup 14} n.cm{sup -2}/sec{sup -1} E<0.625 eV in the reflector) and the JHR's considerable irradiation capabilities (more than 20 experiments and one-tenth of irradiation area for simultaneous radioisotope production), the JHR is the first MTR to be built since the end of the 1960's, making this an especially challenging project. The presentation will provide an overview of the reactor, hot cells and laboratories and an outline of the key milestones in the project schedule, including initial criticality in early 2014 and radioisotope production in 2015. This will be followed by a description of the project organization set up by the CEA as owner and future operator and AREVA TA as prime contractor and supplier of critical systems, and a discussion of project challenges, especially those dealing with the following items: - accommodation of a broad experimental domain, - involvement by international partners making in-kind contributions to the project, - development of components critical to safety and performance, - the revival of engineering of research reactors and experimental devices involving France's historical players in the field of research reactors, and

A successful approach for the implementation of symptom-based emergency operating procedures for VVER reactors

International Nuclear Information System (INIS)

Lhoest, V.; Prior, R.; Pascal, G.

2000-01-01

The paper provides an overview of the organization, the progress and the results of the various Emergence Operating Procedure (EOP) development programs for VVER type reactors conducted by Westinghouse so far. The detailed working process is presented through the solutions to some major plant issues. The EOPs have been developed for the Temelin, Dukovany, Bohunice, Mochovce and Paks VVER nuclear power plants. The procedures are developed in working teams of experts from the utility and Westinghouse. The completion of the programs constitute an indication of the overall success of this approach. This is further reinforced by the general acceptance of the new procedures by the plant personnel, together with the good results obtained so far from procedure testing. This is also confirmed by a new PSA-level 1 analysis for Dukovany plant, which shows a significant improvement in the overall plant safety. This means a 20% reduction in the Core Damage Frequency due to the introduction of the new EOPs. The fact that some modifications have been implemented to the plants to solve design weaknesses identified in the course of this programs also constitute a positive result

Technology requirements for fusion--fission reactors based on magnetic-mirror confinement

International Nuclear Information System (INIS)

Moir, R.W.

1978-01-01

Technology requirements for mirror hybrid reactors are discussed. The required 120-keV neutral beams can use positive ions. The magnetic fields are 8 T or under and can use NbTi superconductors. The value of Q (where Q is the ratio of fusion power to injection power) should be in the range of 1 to 2 for economic reasons relating to the cost of recirculating power. The wall loading of 14-MeV neutrons should be in the range of 1 to 2 MW/m 2 for economic reasons. Five-times higher wall loading will likely be needed if fusion reactors are to be economical. The magnetic mirror experiments 2XIIB, TMX, and MFTF are described

Keeping research reactors relevant: A pro-active approach for SLOWPOKE-2

International Nuclear Information System (INIS)

Cosby, L.R.; Bennett, L.G.I.; Nielsen, K.; Weir, R.

2010-01-01

The SLOWPOKE is a small, inherently safe, pool-type research reactor that was engineered and marketed by Atomic Energy of Canada Limited (AECL) in the 1970s and 80s. The original reactor, SLOWPOKE-1, was moved from Chalk River to the University of Toronto in 1970 and was operated until upgraded to the SLOWPOKE-2 reactor in 1973. In all, eight reactors in the two versions were produced and five are still in operation today, three having been decommissioned. All of the remaining reactors are designated as SLOWPOKE-2 reactors. These research reactors are prone to two major issues: aging components and lack of relevance to a younger audience. In order to combat these problems, one SLOWPOKE -2 facility has embraced a strategy that involves modernizing their reactor in order to keep the reactor up to date and relevant. In 2001, this facility replaced its aging analogue reactor control system with a digital control system. The system was successfully commissioned and has provided a renewed platform for student learning and research. The digital control system provides a better interface and allows flexibility in data storage and retrieval that was never possible with the analogue control system. This facility has started work on another upgrade to the digital control and instrumentation system that will be installed in 2010. The upgrade includes new computer hardware, updated software and a web-based simulation and training system that will allow licensed operators, students and researchers to use an online simulation tool for training, education and research. The tool consists of: 1) A dynamic simulation for reactor kinetics (e.g., core flux, power, core temperatures, etc). This tool is useful for operator training and student education; 2) Dynamic mapping of the reactor and pool container gamma and neutron fluxes as well as the vertical neutron beam tube flux. This research planning tool is used for various researchers who wish to do irradiations (e.g., neutron

Very high flux steady state reactor and accelerator based sources

International Nuclear Information System (INIS)

Ludewig, H.; Todosow, M.; Simos, N.; Shapiro, S.; Hastings, J.

2004-01-01

With the number of steady state neutron sources in the US declining (including the demise of the Bnl HFBR) the remaining intense sources are now in Europe (i.e. reactors - ILL and FMR, accelerator - PSI). The intensity of the undisturbed thermal flux for sources currently in operation ranges from 10 14 n/cm 2 *s to 10 15 n/cm 2 *s. The proposed Advanced Neutron Source (ANS) was to be a high power reactor (about 350 MW) with a projected undisturbed thermal flux of 7*10 15 n/cm 2 *s but never materialized. The objective of the current study is to explore the requirements and implications of two source concepts with an undisturbed flux of 10 16 n/cm 2 *s. The first is a reactor based concept operating at high power density (10 MW/l - 15 MW/l) and a total power of 100 MW - 250 MW, depending on fissile enrichment. The second is an accelerator based concept relying on a 1 GeV - 1.5 GeV proton Linac with a total beam power of 40 MW and a liquid lead-bismuth eutectic target. In the reactor source study, the effects of fissile material enrichment, coolant temperature and pressure drop, and estimates of pressure vessel stress levels will be investigated. The fuel form for the reactor will be different from all other operating source reactors in that it is proposed to use an infiltrated graphitic structure, which has been developed for nuclear thermal propulsion reactor applications. In the accelerator based source the generation of spallation products and their activation levels, and the material damage sustained by the beam window will be investigated. (authors)

Calculations of reactor-accident consequences, Version 2. CRAC2: computer code user's guide

International Nuclear Information System (INIS)

Ritchie, L.T.; Johnson, J.D.; Blond, R.M.

1983-02-01

The CRAC2 computer code is a revision of the Calculation of Reactor Accident Consequences computer code, CRAC, developed for the Reactor Safety Study. The CRAC2 computer code incorporates significant modeling improvements in the areas of weather sequence sampling and emergency response, and refinements to the plume rise, atmospheric dispersion, and wet deposition models. New output capabilities have also been added. This guide is to facilitate the informed and intelligent use of CRAC2. It includes descriptions of the input data, the output results, the file structures, control information, and five sample problems

Eco information 1. Influence of operation of the plants Jadrova vyradovacia spolocnost, a.s., on the environment within January 2009

International Nuclear Information System (INIS)

2009-01-01

In this leaflet the results of monitoring of chemical gaseous and liquid effluents into the rivers Vah and Dudvah as well as of radiation monitoring of Bohunice V1 NPP and Bohunice Radioactive Waste Processing Centre (MSVP) are presented. The radioactive effluents into atmosphere within January - January 2009 (for NPP V1, A1, and MSVP, respectively) were: 0.470 TBq (0.024% of annually limit (AL)) for V1 of rare gases; 0.437 MBq (0.001% AL) for V1), 0.531 MBq (0.06% of AL) for A1 and 0.011 MBq (0.004% of AL) for MSVP) of aero-soles; 4.024 MBq (0.006% of AL) for V1) of iodine. The radioactive effluents into atmosphere and hydrosphere within a January 2009 for NPP V1, A1 and MSVP, respectively) were: 0.470 TBq (V1) of rare gases; 0.437 MBq (V1), 0.531 MBq (A1) and 0.011 MBq (MSVP) of aero-soles; 4.024 MBq (V1) of iodine; 1.358 MBq (V1) and 2.68 MBq (A1 and MSVP, totally) of corrosive and fission products, and 124.4 GBq (V1) and 13.12 GBq (A1 and MSVP, totally) of tritium. For the period January - January 2009 these radioactive effluents into recipient of Vah River represent for corrosive and fission products 1.358 MBq (0.010% of AL) for V1, 2.66 MBq (0.02% of AL) for A1; and for tritium it is 124.4 GBq (0.622% of AL) for V1, 13.12 GBq (0.13% of AL) for A1. Chemical effluents are reported, too

Power cables with extruded insulation and their accessories for rated voltages from 1 kV (Um = 1,2 kV) up to 30 kV (Um = 36 kV) : Part 2: cables for rated voltages from 6 kV (Um = 7,2 kV) up to 30 kV (Um = 36 kV)

CERN Document Server

International Electrotechnical Commission. Geneva

2005-01-01

Power cables with extruded insulation and their accessories for rated voltages from 1 kV (Um = 1,2 kV) up to 30 kV (Um = 36 kV) : Part 2: cables for rated voltages from 6 kV (Um = 7,2 kV) up to 30 kV (Um = 36 kV)

Tokamak engineering test reactor

International Nuclear Information System (INIS)

Conn, R.W.; Jassby, D.L.

1975-07-01

The design criteria for a tokamak engineering test reactor can be met by operating in the two-component mode with reacting ion beams, together with a new blanket-shield design based on internal neutron spectrum shaping. A conceptual reactor design achieving a neutron wall loading of about 1 MW/m 2 is presented. The tokamak has a major radius of 3.05 m, the plasma cross-section is noncircular with a 2:1 elongation, and the plasma radius in the midplane is 55 cm. The total wall area is 149 m 2 . The plasma conditions are T/sub e/ approximately T/sub i/ approximately 5 keV, and ntau approximately 8 x 10 12 cm -3 s. The plasma temperature is maintained by injection of 177 MW of 200-keV neutral deuterium beams; the resulting deuterons undergo fusion reactions with the triton-target ions. The D-shaped toroidal field coils are extended out to large major radius (7.0 m), so that the blanket-shield test modules on the outer portion of the torus can be easily removed. The TF coils are superconducting, using a cryogenically stable TiNb design that permits a field at the coil of 80 kG and an axial field of 38 kG. The blanket-shield design for the inner portion of the torus nearest the machine center line utilizes a neutron spectral shifter so that the first structural wall behind the spectral shifter zone can withstand radiation damage for the reactor lifetime. The energy attenuation in this inner blanket is 8 x 10 -6 . If necessary, a tritium breeding ratio of 0.8 can be achieved using liquid lithium cooling in the []outer blanket only. The overall power consumption of the reactor is about 340 MW(e). A neutron wall loading greater than 1 MW/m 2 can be achieved by increasing the maximum magnetic field or the plasma elongation. (auth)

WWER-1000 reactor simulator. Material for training courses and workshops. 2. ed

International Nuclear Information System (INIS)

2005-01-01

The International Atomic Energy Agency (IAEA) has established an activity in nuclear reactor simulation computer programs to assist its Member States in education. The objective is to provide, for a variety of advanced reactor types, insight and practice in their operational characteristics and their response to perturbations and accident situations. To achieve this, the IAEA arranges for the development and distribution of simulation programs and educational material and sponsors courses and workshops. The workshops are in two parts: techniques and tools for reactor simulator development; and the use of reactor simulators in education. Workshop material for the first part is covered in the IAEA publication: Training Course Series No.12, Reactor Simulator Development (2001). Course material for workshops using a pressurized water reactor (PWR) simulator developed for the IAEA by Cassiopeia Technologies Inc. of Canada is presented in the IAEA publication, Training Course Series No. 22, 2nd edition, Pressurized Water Reactor Simulator (2005) and Training Course Series No.23, 2nd edition, Boiling Water Reactor Simulator (2005). This report consists of course material for workshops using the WWER-1000 Reactor Department Simulator from the Moscow Engineering and Physics Institute, Russian Federation

ASAMPSA2 best-practices guidelines for L2 PSA development and applications. Volume 3 - Extension to Gen IV reactors

International Nuclear Information System (INIS)

Bassi, C.; Bonneville, H.; Brinkman, H.; Burgazzi, L.; Polidoro, F.; Vincon, L.; Jouve, S.

2010-01-01

The main objective assigned to the Work Package 4 (WP4) of the 'ASAMPSA2' project (EC 7. FPRD) consist in the verification of the potential compliance of L2PSA guidelines based on PWR/BWR reactors (which are specific tasks of WP2 and WP3) with Generation IV representative concepts. Therefore, in order to exhibit potential discrepancies between LWRs and new reactor types, the following work was based on the up-to-date designs of: - The European Fast Reactor (EFR) which will be considered as prototypical of a pool-type Sodium-cooled Fast Reactor (SFR); - The ELSY design for the Lead-cooled Fast Reactor (LFR) technology; - The ANTARES project which could be representative of a Very-High Temperature Reactor (VHTR); - The CEA 2400 MWth Gas-cooled Fast Reactor (GFR). (authors)

Neuronal responses in visual area V2 (V2) of macaque monkeys with strabismic amblyopia.

Science.gov (United States)

Bi, H; Zhang, B; Tao, X; Harwerth, R S; Smith, E L; Chino, Y M

2011-09-01

Amblyopia, a developmental disorder of spatial vision, is thought to result from a cascade of cortical deficits over several processing stages beginning at the primary visual cortex (V1). However, beyond V1, little is known about how cortical development limits the visual performance of amblyopic primates. We quantitatively analyzed the monocular and binocular responses of V1 and V2 neurons in a group of strabismic monkeys exhibiting varying depths of amblyopia. Unlike in V1, the relative effectiveness of the affected eye to drive V2 neurons was drastically reduced in the amblyopic monkeys. The spatial resolution and the orientation bias of V2, but not V1, neurons were subnormal for the affected eyes. Binocular suppression was robust in both cortical areas, and the magnitude of suppression in individual monkeys was correlated with the depth of their amblyopia. These results suggest that the reduced functional connections beyond V1 and the subnormal spatial filter properties of V2 neurons might have substantially limited the sensitivity of the amblyopic eyes and that interocular suppression was likely to have played a key role in the observed alterations of V2 responses and the emergence of amblyopia.

Comparison of 2D and 3D Neutron Transport Analyses on Yonggwang Unit 3 Reactor

International Nuclear Information System (INIS)

Maeng, Aoung Jae; Kim, Byoung Chul; Lim, Mi Joung; Kim, Kyung Sik; Jeon, Young Kyou; Yoo, Choon Sung

2012-01-01

10 CFR Part 50 Appendix H requires periodical surveillance program in the reactor vessel (RV) belt line region of light water nuclear power plant to check vessel integrity resulting from the exposure to neutron irradiation and thermal environment. Exact exposure analysis of the neutron fluence based on right modeling and simulations is the most important in the evaluation. Traditional 2 dimensional (D) and 1D synthesis methodologies have been widely applied to evaluate the fast neutron (E > 1.0 MeV) fluence exposure to RV. However, 2D and 1D methodologies have not provided accurate fast neutron fluence evaluation at elevations far above or below the active core region. RAPTOR-M3G (RApid Parallel Transport Of Radiation - Multiple 3D Geometries) program for 3D geometries calculation was therefore developed both by Westinghouse Electronic Company, USA and Korea Reactor Integrity Surveillance Technology (KRIST) for the analysis of In-Vessel Surveillance Test and Ex-Vessel Neutron Dosimetry (EVND). Especially EVND which is installed at active core height between biological shielding material and concrete also evaluates axial neutron fluence by placing three dosimetries each at Top, Middle and Bottom part of the angle representing maximum neutron fluence. The EVND programs have been applied to the Korea Nuclear Plants. The objective of this study is therefore to compare the 3D and the 2D Neutron Transport Calculations and Analyses on the Yonggwang unit 3 Reactor as an example

Recent events at Bohunice NPP Slovak Republic

International Nuclear Information System (INIS)

Lipar, M.

1996-01-01

During a filter regeneration in the steam generators (SG) blow down purification system at full power, approximately 900 litres of NaOH penetrated through a condensate collection tank into the main turbine condenser and subsequently into three SGs. The penetration occurred because of a valve left open during the filter regeneration due to a valve configuration error. The water in the tree SGs foamed, causing unexpected behaviour in SG level indicators which led to a reactor scram. By exceeding the pH value of feedwater for 7 minutes, the technical specification were violated, until the unit was brought into hot shut-down mode. Figs

Current status of restoration work for obstacle and upper core structure in reactor vessel of experimental fast reactor 'Joyo'. 2-2

International Nuclear Information System (INIS)

Okuda, Eiji; Ito, Hiromichi; Yoshihara, Shizuya

2014-01-01

An accident occurred in experimental fast reactor 'Joyo' in 2007 which is obstruction of fuel change equipment caused by contacting rotating plug and MARICO-2. In addition, we confirmed two happenings in the reactor vessel that (1) Deformation of MARICO-2 subassembly on the in vessel storage rack together with a transfer pot, (2) Deformation of the Upper core structure of 'Joyo' caused by contacting MARICO-2 subassembly and the UCS. We do the restoration work for restoring it. This time, we describe current status of Replacement work of the UCS. (author)

Oxidation of SO{sub 2} in a trickle bed reactor packed with activated carbon at low liquid flow rates

Energy Technology Data Exchange (ETDEWEB)

Suyadal, Y.; Oguz, H. [Ankara Univ. (Turkey). Dept. of Chemical Engineering

2000-07-01

In this study, the oxidation of SO{sub 2} on activated carbon (AcC) by using distilled water and air was carried out in a laboratory scale trickle bed reactor (TBR). Distilled water and air containing 1.7% (v/v) SO{sub 2} were fed co-currently downward through a fixed bed of AcC particles in a range of 1-7 cm{sup 3}/s and 10-27 cm{sup 3}/s, respectively. H{sub 2}SO{sub 3}/H{sub 2}SO{sub 4} solutions were the products obtained in the liqiuid phase. Steady-state experiments were performed in a column of 0.15 m packing height and 0.047 m column diameter at 20 C and atmospheric pressure. (orig.)

Comparison of results for burning with BWR reactors CASMO and SCALE 6.2 (TRITON / NEWT); Comparacion de los resultados de quemado para reactores BWR con CASMO y SCALE 6.2 (TRITON/NEWT)

Energy Technology Data Exchange (ETDEWEB)

Mesado, C.; Miro, R.; Barrachina, T.; Verdu, G.

2014-07-01

In this paper we compare the results from two codes burned, CASMO and SCALE 6.2 (TRITON). To do this, is simulated all segments corresponding to a boiling water reactor (BWR) using both codes. In addition, to account for different working points, simulations changing the instantaneous variables, these are repeated: void fractions (6 points), fuel temperature (6 points) and control rods (two points), with a total of 72 possible combinations of different instantaneous variables for each segment. After all simulations are completed for each segment, we can reorder the obtained cross sections, as SCALE CASMO both, to create a library of compositions nemtab format. This format is accepted by the neutronic code of nodal diffusion, PARCS v2.7. Finally compares the results obtained with PARCS and with the SIMULATE3 -SIMTAB methodology to level of full reactor. Also, we have made use of the KENO-VI and MCDANCOFF modules belonging to SCALE. The first is a Monte Carlo transport code with which you can validate the value of the multiplier, the second has been used to obtain values of Dancoff factor and increase the accuracy of model SCALE. (Author)

NH{sub 3} decomposition and simultaneous H{sub 2} separation with a commercial Pd-Cu-Ag/V membrane

Energy Technology Data Exchange (ETDEWEB)

Skodras, G.; Sakelleropoulos, G. [Centre for Research and Technology, Hellas, Ptolemaidas-Kozanis, Ptolemaida (Greece). Inst. for Solid Fuel Technolgy and Applications]|[Aristotle Univ. of Thessaloniki, Thessaloniki (Greece). Dept. of Chemical Engineering, Chemical Process Engineering Lab]|[Centre for Research and Technology, Hellas, Thermis, Thessaloniki (Greece). Chemical Process Research Inst.; Kaldis, S. [Centre for Research and Technology, Hellas, Thermis, Thessaloniki (Greece). Chemical Process Research Inst.; Topis, S. [Centre for Research and Technology, Hellas, Ptolemaidas-Kozanis, Ptolemaida (Greece). Inst. for Solid Fuel Technolgy and Applications]|[Aristotle Univ. of Thessaloniki, Thessaloniki (Greece). Dept. of Chemical Engineering, Chemical Process Engineering Lab; Koutsonikolas, D. [Aristotle Univ. of Thessaloniki, Thessaloniki (Greece). Dept. of Chemical Engineering, Chemical Process Engineering Lab; Grammelis, P. [Centre for Research and Technology, Hellas, Ptolemaidas-Kozanis, Ptolemaida (Greece). Inst. for Solid Fuel Technolgy and Applications

2006-07-01

The potential for integrated gasification combined cycle (IGCC) technology to emerge as an efficient and environmentally clean technology for power generation from coal gas was discussed. Ammonia (NH{sub 3}) is formed during gasification of coal. The concentration in coal gas depends on temperature, pressure, residence time and coal rank. In the gas turbine as much as 50 per cent of the NH{sub 3} in the fuel gas can be converted to NOx when the gas is combusted to produce power. A catalyst is required to bring NH{sub 3} levels down to acceptable levels for a gas turbine. This study examined the simultaneous ammonia (NH{sub 3}) decomposition and hydrogen (H{sub 2}) separation via a commercial Pd-Cu-Ag/V catalytic membrane reactor with 100 per cent H{sub 2} selectivity. A 16 per cent Ni/Al{sub 2}O{sub 3} catalyst was prepared and 88 per cent NH{sub 3} conversion was achieved with 20 per cent H{sub 2} in the feed stream. Increase of temperature and prolongation of residence time resulted in higher conversions. However, pressure increase lowered the decomposition due to the high H{sub 2} partial pressure. In order to develop kinetic equations, experiments at differential conversions were also performed. H{sub 2} diffusion was found to be the rate limiting step of H{sub 2} transport through the membrane. As such, H{sub 2} permeance increased exponentially with temperature. Mathematical model were then developed to describe the operation of the catalytic membrane reactor and to compare its performance with the conventional reactor. It was concluded that the conversion of NH{sub 3} can be increased significantly using the Pd-Cu-Ag/V membrane. 14 refs., 3 tabs., 7 figs.

Potential performance analysis and future trend prediction of electric vehicle with V2G/V2H/V2B capability

Directory of Open Access Journals (Sweden)

Dalong Guo

2016-03-01

Full Text Available Due to the intermittent nature, renewable energy sources (RES has brought new challenges on load balancing and energy dispatching to the Smart Grid. Potentially served as distributed energy storage, Electric Vehicle’s (EV battery can be used as a way to help mitigate the pressure of fluctuation brought by RES and reinforce the stability of power systems. This paper gives a comprehensive review of the current situation of EV technology and mainly emphasizing three EV discharging operations which are Vehicle to Grid (V2G, Vehicle to Home (V2H, and Vehicle to Building (V2B, respectively. When needed, EV’s battery can discharge and send its surplus energy back to power grid, residential homes, or buildings. Based on our data analysis, we argue that V2G with the largest transmission power losses is potentially less efficient compared with the other two modes. We show that the residential users have the incentive to schedule the charging, V2G, and V2H according to the real-time price (RTP and the market sell-back price. In addition, we discuss some challenges and potential risks resulting from EVs’ fast growth. Finally we propose some suggestions on future power systems and also argue that some incentives or rewards need to be provided to motivate EV owners to behave in the best interests of the overall power systems.