Overview of VVER water chemistry

International Nuclear Information System (INIS)

Ganesh, S.; Selvaraj, S.; Balasubramanian, M.R.; Selvavinayagam, P.; Sundar, R.S.

2007-01-01

Kudankulam Nuclear Power project is having twin units of 1000MWe of VVER type. This paper highlights the different analytical techniques that are followed to maintain the system chemistry within the technical specifications. This paper also briefs the different chemicals that are added to the systems and how they are monitored. Basic differences with respect to chemistry between a PHWR and VVER are also highlighted in this paper. (author)

Problems and prospects connected with development of high-temperature filtration technology at nuclear power plants equipped with VVER-1000 reactors

Science.gov (United States)

Shchelik, S. V.; Pavlov, A. S.

2013-07-01

Results of work on restoring the service properties of filtering material used in the high-temperature reactor coolant purification system of a VVER-1000 reactor are presented. A quantitative assessment is given to the effect from subjecting a high-temperature sorbent to backwashing operations carried out with the use of regular capacities available in the design process circuit in the first years of operation of Unit 3 at the Kalinin nuclear power plant. Approaches to optimizing this process are suggested. A conceptual idea about comprehensively solving the problem of achieving more efficient and safe operation of the high-temperature active water treatment system (AWT-1) on a nuclear power industry-wide scale is outlined.

Interactive nuclear plant analyzer for VVER-440 reactor

International Nuclear Information System (INIS)

Shier, W.; Horak, W.; Kennett, R.

1992-05-01

This document discusses an interactive nuclear plant analyzer (NPA) which has been developed for a VVER-440, Model 213 reactor for use in the training of plant personnel, the development and verification of plant operating procedures, and in the analysis of various anticipated operational occurrences and accident scenarios. This NPA is operational on an IBM RISC-6000 workstation and utilizes the RELAP5/MOD2 computer code for the calculation of the VVER-440 reactor response to the interactive commands initiated by the NPA operator

FP 6 EU - COVERS. Coordination action - VVER safety research

International Nuclear Information System (INIS)

Vasa, I.

2008-01-01

In this work research program of the European Union FP 6 - COVERS coordinated by the NRI Rez is presented. COVERS is designed to improve professional and communication environment in the specific area covering all aspects of safe and reliable operation of nuclear power plants with VVER-440 and VVER-1000 reactors. Project Consortium is composed of 26 research and development, engineering and technical support organisations of European VVER-operating and other EU and non-EU countries.

The role of PRA in the safety assessment of VVER Nuclear Power Plants in Ukraine

International Nuclear Information System (INIS)

Kot, C.

1999-01-01

Ukraine operates thirteen (13) Soviet-designed pressurized water reactors, VVERS. All Ukrainian plants are currently operating with annually renewable permits until they update their safety analysis reports (SARs), in accordance with new SAR content requirements issued in September 1995, by the Nuclear Regulatory Authority and the Government Nuclear Power Coordinating Committee of Ukraine. The requirements are in three major areas: design basis accident (DBA) analysis, probabilistic risk assessment (PRA), and beyond design-basis accident (BDBA) analysis. The last two requirements, on PRA and BDBA, are new, and the DBA requirements are an expanded version of the older SAR requirements. The US Department of Energy (USDOE), as part of its Soviet-Designed Reactor Safety activities, is providing assistance and technology transfer to Ukraine to support their nuclear power plants (NPPs) in developing a Western-type technical basis for the new SARs. USDOE sponsored In-Depth Safety Assessments (ISAs) are in progress at three pilot nuclear reactor units in Ukraine, South Ukraine Unit 1, Zaporizhzhya Unit 5, and Rivne Unit 1, and a follow-on study has been initiated at Khmenytskyy Unit 1. The ISA projects encompass most areas of plant safety evaluation, but the initial emphasis is on performing a detailed, plant-specific Level 1 Internal Events PRA. This allows the early definition of the plant risk profile, the identification of risk significant accident sequences and plant vulnerabilities and provides guidance for the remainder of the safety assessments

Control of selected VVER components life time SKODA JS a.s. experience

International Nuclear Information System (INIS)

Zdebor, J.; Pribulla, E.

2005-01-01

Experience from the operation of nuclear power plants with type VVER reactors has shown that the life time management of a number of nuclear reactor components is technically as well as with respect to safety substantiated even at the time which exceeds their originally designed life time. To accept such solution it was necessary to develop and implement a number of programs based on which it was possible to evaluate the actual condition of monitored equipment. It is a condition allowing to adopt solution concerning the possibility of their further operation. Experience from the manufacture of 21 sets of reactor equipment for VVER 440 and 3 sets VVER 1000 has been gathered in SKODA JS a.s. which have been completed by experience from service activities performed at operated nuclear power plants. Analyses of manufacturing data and in-service inspection results completed by a lot of laboratory tests have become the basis for the development of selected VVER components life time management programs. The paper focuses on the life time management of those VVER components which SKODA JS a.s. has most experience with. (authors)

Enhancement of Training Capabilities in VVER Technology Through Establishment of VVER Training Academy

International Nuclear Information System (INIS)

Ilieva, M.; Miteva, R.

2015-01-01

Education and training (E&T) have always been key factor to the sustainability of the nuclear industry. With regard to E&T it is still the challenge to raise the interest of qualified young people of studies and professions related to nuclear technologies. CORONA Project is established to provide a special purpose structure for training and for gathering the existing and generating new knowledge in the VVER area as well as to contribute to transnational mobility and lifelong learning amongst VVER operating countries. CORONA Project consists of two parts: CORONA I (2011–2014) “Establishment of a regional centre of competence for VVER technology and Nuclear Applications”, co-financed by the EC Framework Programme 7 and CORONA II “Enhancement of training capabilities in VVER technology through establishment of VVER training academy”, co-financed by the EURATOM 2014-2015 Working programme of HORIZON 2020. The project is focused on development of training schemes for VVER nuclear professionals, subcontractors, students and for non-nuclear specialists working in support of nuclear applications as civil engineers, physical protection employees, government employees, secondary school teachers, journalists. Safety culture and soft skills training are incorporated as an integral part of all training schemes because they require continuous consideration. It is vital for the acceptance of nuclear energy by the public and for the safe performance of the nuclear installations. CORONA II project is to proceed with the development of state-of-the-art virtual training centre — CORONA Academy. This objective will be realised through networking between universities, research organizations, regulatory bodies, industry and any other organizations involved in the application of nuclear science, ionising radiation and nuclear safety. It will bring together the most experienced trainers and will allow trainees from different locations to access the needed knowledge on demand

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

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.

Analysis of core damage frequency: Nuclear power plant Dukovany, VVER/440 V-213 Unit 1, internal events. Volume 1: Main report

International Nuclear Information System (INIS)

Pugila, W.J.

1994-01-01

This report presents the final results from the Level 1 probabilistic safety assessment (PSA) for the Dukovany VVER/440 V-213 nuclear power plant, Unit 1. Section 1.1 describes the objectives of this study. Section 1.2 discusses the approach that was used for completing the Dukovany PSA. Section 1.3 summarizes the results of the PSA. Section 1.4 provides a comparison of the results of the Dukovany PSA with the results of other PSAs for different types of reactors worldwide. Section 1.5 summarizes the conclusions of the Dukovany PSA

Three-dimensional reactor dynamics code for VVER type nuclear reactors

Energy Technology Data Exchange (ETDEWEB)

Kyrki-Rajamaeki, R. [VTT Energy, Espoo (Finland)

1995-10-01

A three-dimensional reactor dynamics computer code has been developed, validated and applied for transient and accident analyses of VVER type nuclear reactors. This code, HEXTRAN, is a part of the reactor physics and dynamics calculation system of the Technical Research Centre of Finland, VTT. HEXTRAN models accurately the VVER core with hexagonal fuel assemblies. The code uses advanced mathematical methods in spatial and time discretization of neutronics, heat transfer and the two-phase flow equations of hydraulics. It includes all the experience of VTT from 20 years on the accurate three-dimensional static reactor physics as well as on the one-dimensional reactor dynamics. The dynamic coupling with the thermal hydraulic system code SMABRE also allows the VVER circuit-modelling experience to be included in the analyses. (79 refs.).

Three-dimensional reactor dynamics code for VVER type nuclear reactors

International Nuclear Information System (INIS)

Kyrki-Rajamaeki, R.

1995-10-01

A three-dimensional reactor dynamics computer code has been developed, validated and applied for transient and accident analyses of VVER type nuclear reactors. This code, HEXTRAN, is a part of the reactor physics and dynamics calculation system of the Technical Research Centre of Finland, VTT. HEXTRAN models accurately the VVER core with hexagonal fuel assemblies. The code uses advanced mathematical methods in spatial and time discretization of neutronics, heat transfer and the two-phase flow equations of hydraulics. It includes all the experience of VTT from 20 years on the accurate three-dimensional static reactor physics as well as on the one-dimensional reactor dynamics. The dynamic coupling with the thermal hydraulic system code SMABRE also allows the VVER circuit-modelling experience to be included in the analyses. (79 refs.)

Possible emission of radioactive fission products during off-design accidents at a nuclear power plant with VVER-1000 reactor

International Nuclear Information System (INIS)

Dubkov, A.P.; Kozlov, V.F.; Luzanova, L.M.

1995-01-01

It is well known that eight nuclear power plants with VVER-1000 reactors have been constructed in Russia, Ukraine, and in the Republic of Belarus and they have been operating successfully without any serious accidents since 1980. These facilities have been analyzed for various accident scenarios, and measures have been incorporated which will prevent core damage during these possible events. However, an off-design accident can occur, and in such a case, the radiological consequences would exceed the worst design accidents. This paper reviews a number of potential off-design accidents in order to develop an accident plan to mitigate the consequences of such an accident

VVER-1000 backfitting programs

International Nuclear Information System (INIS)

Zabka, H.; Milhem, J.L.

1998-01-01

Russia, Ukraine, and Bulgaria have nineteen nuclear generating units of the VVER-1000/V-320 (1000 MWe PWR) type in operation. Most of these plants were built in the eighties. Their design is based on Soviet standards of the seventies. In the early eighties and, in particular, after the Chernobyl accident, new safety principles and supplementary specific standards were introduced. However, they were taken into account only to a limited extent in the design and construction of the VVER-1000/V-320 plants. A number of nuclear power plants, whose construction was stopped after the political changes in the countries of the former USSR, now are to be completed with the financial assistance of the Commission of the European Union and other Western organizations, respectively. This Western support is dependent on the condition that these plants attain a level of engineered safeguards comparable to that of PWR plants currently in operation in Western Europe. (orig.) [de

Innovative instrumentation for VVERs based in non-invasive techniques

International Nuclear Information System (INIS)

Jeanneau, H.; Favennec, J.M.; Tournu, E.; Germain, J.L.

2000-01-01

Nuclear power plants such as VVERs can greatly benefit from innovative instrumentation to improve plant safety and efficiency. In recent years innovative instrumentation has been developed for PWRs with the aim of providing additional measurements of physical parameters on the primary and secondary circuits: the addition of new instrumentation is made possible by using non-invasive techniques such as ultrasonics and radiation detection. These innovations can be adapted for upgrading VVERs presently in operation and also in future VVERs. The following innovative instrumentation for the control, monitoring or testing at VVERs is described: 1. instrumentation for more accurate primary side direct measurements (for a better monitoring of the primary circuit); 2. instrumentation to monitor radioactivity leaks (for a safer plant); 3. instrumentation-related systems to improve the plant efficiency (for a cheaper kWh)

Presenting a model of repair and preventing maintenance of Bushehr nuclear power plants analyzing the data of similar nuclear power plants

International Nuclear Information System (INIS)

Parikhan, Hammidreza

1997-01-01

Due to the increase application of nuclear energy for producing electricity, special attention must be paid to their maintenance activities in general and preventive maintenance in particular. It has been shown that a well established preventive maintenance programme will enhance the reliability and availability of nuclear power plants. A model of preventive maintenance for Buhehr nuclear power plant which is due to be completed by 2001 is developed. The prescribed model is based on past experiences of VVER nuclear power plants around the world. The utilized data is provided by International Atomic Energy Agency (IAEA) in Vienna, Austria. The data and past experiences reveal such important information as availability, energy loss, types of failures, duration of failure, etc. A strategy for designing a database is established. These data are then analyzed by statistical methods such as Pareto analysis, t-test, K-S test, analysis of variance, etc. The results of our analysis reveal important information in regard to establishment of a well-defined preventive maintenance programme in Buhshehr nuclear power plant. The results show that certain equipment such turbo-generator and control-rods play an important role in the maintenance of a VVER nuclear power plant. Other findings are discussed in great detail

SCORPIO-VVER core monitoring and surveillance system with advanced capabilities

International Nuclear Information System (INIS)

Molnar, J.; Vocka, R.

2009-01-01

The SCORPIO-VVER system includes following features: 1) Validation of plant measurements and identification of sensor failures. 2) Optimum combination of measurements and calculations to obtain precise values of important parameters. 3) On-line 3D power distribution calculation with pin power reconstruction. 4) Limit checking and thermal margin calculation allowing for surveillance of VVER core limits such as DNBR, Sub-cooling margin, FdH and FQ peeking factors. 5) Integrated modules for monitoring fuel performance and coolant activity for identification of fuel failures. 6) Predictive capabilities and strategy planning, offering the possibility to check the consequences of operational manoeuvres in advance, prediction of critical parameters, etc. 7) Convenient monitoring of approach to criticality during reactor start-up. 8) Automated transition between cycles (fuel reload). The SCORPIO-VVER core monitoring system with its flexible and modular framework successfully responses to the plant operating needs and advances in nuclear fuel cycle strategies and fuel design. Modular framework allows for easy modifications of the system and implementation of new methods in physical modules. Even if the system is installed only on VVER-440 reactors, it could be adapted for VVER-1000 needs

Operation of Nuclear Fuel Based on Reprocessed Uranium for VVER-type Reactors in Competitive Nuclear Fuel Cycles

Energy Technology Data Exchange (ETDEWEB)

Troyanov, V.; Molchanov, V.; Tuzov, A. [TVEL Corporation, 49 Kashirskoe shosse, Moscow 115409 (Russian Federation); Semchenkov, Yu.; Lizorkin, M. [RRC ' Kurchatov Institute' (Russian Federation); Vasilchenko, I.; Lushin, V. [OKB ' Gidropress' (Russian Federation)

2009-06-15

Current nuclear fuel cycle of Russian nuclear power involves reprocessed low-enriched uranium in nuclear fuel production for some NPP units with VVER-type LWR. This paper discusses design and performance characteristics of commercial nuclear fuel based on natural and reprocessed uranium. It presents the review of results of commercial operation of nuclear fuel based on reprocessed uranium on Russian NPPs-unit No.2 of Kola NPP and unit No.2 of Kalinin NPP. The results of calculation and experimental validation of safe fuel operation including necessary isotope composition conformed to regulation requirements and results of pilot fuel operation are also considered. Meeting the customer requirements the possibility of high burn-up achieving was demonstrated. In addition the paper compares the characteristics of nuclear fuel cycles with maximum length based on reprocessed and natural uranium considering relevant 5% enrichment limitation and necessity of {sup 236}U compensation. The expedience of uranium-235 enrichment increasing over 5% is discussed with the aim to implement longer fuel cycles. (authors)

French-Finnish colloquium on safety of French and Russian type nuclear power plants

International Nuclear Information System (INIS)

Lukka, M.; Jaervinen, M.; Minkkinen, P.; Ukkola, A.; Levomaeki, L.

1994-01-01

The French-Finnish Colloquium on Safety of French and Russian Type Nuclear Power Plants was held in June, 14th - 16th, 1994, in Lappeenranta, Finland. The main topics of the colloquium were: VVER and RBMK reactors; Industrial safety studies for VVER's in FRAMATOME; Structural safety analysis of Ignalina NPP; Thermalhydraulic system (BETHSY) and analytical experiments for French NPP; Test facilities simulating VVER plants during accidents; PACTEL - facility for VVER thermal hydraulics; High burn-up fuel and reactivity accidents; Overview of severe accident research at Nuclear Protection and Safety Institute of CEA; Research of severe accidents in Finland; Review of main activities concerning computer codes used for VVER thermal-hydraulic safety analysis in OKB Gidropress; CATHARE code; APROS computer code, new developments; TRIO and TOLBIAC computer codes; ESTET and N3S softwares; HEXTRAN - 3D reactor dynamics code for VVER accident analysis; An overview the boron dilution issue in PWRs; Boron mixing transients in a 900 MW PWR vessel for a reactor start-up operation; and Problem of boric acid dilution in IVO

Investigation of station blackout scenario in VVER440/v230 with RELAP5 computer code

Energy Technology Data Exchange (ETDEWEB)

Gencheva, Rositsa Veselinova, E-mail: roseh@mail.bg; Stefanova, Antoaneta Emilova, E-mail: antoanet@inrne.bas.bg; Groudev, Pavlin Petkov, E-mail: pavlinpg@inrne.bas.bg

2015-12-15

Highlights: • We have modeled SBO in VVER440. • RELAP5/MOD3 computer code has been used. • Base case calculation has been done. • Fail case calculation has been done. • Operator and alternative operator actions have been investigated. - Abstract: During the development of symptom-based emergency operating procedures (SB-EOPs) for VVER440/v230 units at Kozloduy Nuclear Power Plant (NPP) a number of analyses have been performed using the RELAP5/MOD3 (Carlson et al., 1990). Some of them investigate the response of VVER440/v230 during the station blackout (SBO). The main purpose of the analyses presented in this paper is to identify the behavior of important VVER440 parameters in case of total station blackout. The RELAP5/MOD3 has been used to simulate the SBO in VVER440 NPP model (Fletcher and Schultz, 1995). This model was developed at the Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences (INRNE-BAS), Sofia, for analyses of operational occurrences, abnormal events and design based scenarios. The model provides a significant analytical capability for specialists working in the field of NPP safety.

Interactive nuclear plant analyzer for the VVER-440 reactor

International Nuclear Information System (INIS)

Shier, W.; Kennett, R.

1993-01-01

An interactive nuclear plant analyzer (NPA) has been developed for a VVER-440 model 213 reactor for use in the training of plant personnel, the development and verification of plant operating procedures, and in the analysis of various anticipated operational occurrences and accident scenarios. This NPA is operational on an IBM RISC-6000 workstation and utilizes the RELAP5/MOD2 computer code for the calculation of the VVER-440 reactor response to the interactive commands initiated by the NPA operator. Results of the interactive calculation can be through the user-defined, digital display of various plant parameters and through color changes that reflect changes in primary system fluid temperatures, fuel and clad temperatures, and the temperatures of other metal structures. In addition, changes in the status of various components and system can be initiated and/or displayed both numerically and graphically on the mask

Effect of a dual-purpose cask payload increment of spent fuel assemblies from VVER 1000 Bushehr Nuclear Power Plant on basket criticality

International Nuclear Information System (INIS)

Rezaeian, M.; Kamali, J.

2017-01-01

Dual-purpose casks can be utilized for dry interim storage and transportation of the highly radioactive spent fuel assemblies (SFAs) of Bushehr Nuclear Power Plant (NPP). Criticality safety analysis was carried out using the MCNP code for the cask containing 12, 18, or 19 SFAs. The basket materials of borated stainless steel and Boral (Al-B_4C) were investigated, and the minimum required receptacle pitch of the basket was determined. - Highlights: • Criticality safety analysis for a dual purpose cask was carried out. • The basket material of borated stainless steel and Boral were investigated. • Minimum receptacle pitch was determined for 12, 18, or 19 VVER 1000 spent fuel assemblies.

Results of VVER fuel rods tests in the MIR.M1 reactor under power cycling conditions

International Nuclear Information System (INIS)

Burukin, A.; Izhutov, A.; Ovchinnikov, V.; Kalygin, V.; Markov, D.; Pimenov, Y.; Novikov, V.; Medvedev, A.; Nesterov, B.

2011-01-01

The paper presents the main results of the 50 ... 60 MWd/kgU burnup VVER fuel rods tests performed in the MIR.M1 reactor loop facilities under power cycling. The non-destructive PIE results are presented as well. A series of experiments was performed, including overall measurement of fuel rod parameters test, in one of which 300 cycles were done. Irradiation under power cycling conditions and PIE of high-burnup VVER fuel rods showed the following: 1) all fuel rods claddings preserved their integrity under irradiation at linear heat rate (LHR) higher than the NPP operating one; 2) experimental data were obtained on the axial and radial cladding strain and fission gas release (FGR) from 50 ... 60 MWd/kgU burnup VVER-440 and VVER-1000 fuel rods as well as on the kinetics of the change in these parameters and fuel temperature under the power cycling; 3) non-destructive PIE results are in a satisfactory correlation with the data obtained by means of in-pile measurement gages during irradiation. (authors)

The safety of nuclear power plants in Eastern Europe

International Nuclear Information System (INIS)

Hoehn, J.; Niehaus, F.

1997-01-01

Nuclear power plant operators and nuclear organizations from the West and from the East cooperate at many levels. The G7 and G24 nations have taken it upon themselves to improve the safety of Eastern nuclear power plants. The European Union has launched support programs, i.e. Technical Assistance to the Commonwealth of Independent States (Tacis) and Pologne-Hangrie: Aide a la Reconstruction Economique (Phare), and founded the European Bank for Reconstruction and Development. The countries of Central and Eastern Europe operate nuclear power plants equipped with VVER-type pressurized water reactors and those equipped with RBMK-type reactors. The safety of these two types of plants is judged very differently. Among the VVER plants, a distinction is made between the older and the more recent 440 MWe lines and the 1000 MWe line. Especially the RBMK plants (Chernobyl-type plants) differ greatly as a function of location and year of construction. Even though they do not meet Western safety standards and at best can be backfitted up to a certain level, it must yet be assumed that they will remain in operation to the end of their projected service lives for economic reasons. (orig.) [de

Special features of embrittlement of welded joints in shells of VVER-type reactors

International Nuclear Information System (INIS)

Kasatkin, O.G.

1999-01-01

At present, the atomic power engineering of Russia and Ukraine is based on water-water energy reactors of the VVER-440 and VVER-1000 type, with the electric power of 440 and 1000 MW, respectively. The majority of the VVER-440 reactors are installed in Russia, and VVER-1000 reactors operate in Ukraine. The reactors' shell (RS) is produced from cylindrical shells and a dished end welded together by circular joints under a flux. The RS of the VVER-440 reactor is produced from 15Kh3MFA steel, and the VVER-1000 reactors are produced from 15Kh2NMFA steel. The shell of the VVER-1000 reactor has an internal austenite coating. The condition of the RS metal is determined mainly by the critical brittleness temperature T b at which the impact toughness of specimens with a sharp notch reaches 60 J/cm 2 . The energy reactors, working in western countries, are characterised by a service life of 40 years and discussion is being carried out to extend this lifetime to 60 years. The design service life of the domestic reactors varies from 30 (RS VVER-440) to 40 (RS VVER-1000) years. According to investigations, the service life of the shells of these reactors is restricted by the properties of welded joints which are characterised by higher susceptibility to embrittlement than that of the parent metal, especially due to a higher content in the weld of phosphorus (RS VVER-440) or nickel (RS VVER-1000). Therefore, some experts believe that the actual service life of the RS is shorter than the design life. The accurate evaluation of the service life of welded joints in the RS is very important for the safety of service and also in the economic aspects, because the unjustified decrease of the permissible service life and premature shutdown of units of the nuclear power station result in huge losses

Structural strength during severe reactor accidents of the VVER- 91 nuclear power plant

International Nuclear Information System (INIS)

Varpasuo, P.

1999-12-01

The report summarises the studies carried out in Fortum Engineering (formerly IVO Power Engineering) between the years of 1992 and 1997 concerning ultimate strength of structures designed to mitigate and contain the consequences of various core melt accident scenarios. The report begins with the description of containment loading situations arising from core melt accidents. These situations are divided to fast and slow loads. Fast loads include ex-vessel steam explosions, steam spikes, hydrogen burns, direct containment heating and missiles. Slow loads are connected with pressure rise inside the containment in case when the containment heat removal system is not functioning. First part of report describes the analyses of reactor cavity based on axi-symmetric load assumptions. These studies are performed with various models like one degree of freedom idealisation, axi-symmetric modelling of geometry and full three-dimensional modelling of geometry. Second part of report describes the analyses of cavity based on non-axi-symmetric load assumptions. Here full 3D- geometry model is used combined with various physical models for the behaviour of reinforced concrete. Third part of report gives short account of the analysis of containment ultimate pressure capacity. The containment model in this case includes pre-stressing tendons and mild steel reinforcing bars. The load is assumed to axi-symmetric internal static pressure. The capacity of the reactor cavity against the ex-vessel steam explosion scenarios for VVER-91 plant concept is established for both axi-symmetric and non-axi-symmetric load models using ANACAP structural analysis code. The validation of the cavity response to ex-vessel steam explosion load using different commercially available codes gave mixed results for both axisymmetric and non-axi-symmetric load presentations.The ultimate static overpressure capacity of the VVER-91 reactor cavity structure was established to be of the order of 10 MPa. This result

IVO participation in IAEA benchmark for VVER-type nuclear power plants seismic analysis and testing

International Nuclear Information System (INIS)

Varpasuo, P.

1997-12-01

This study is a part of the IAEA coordinated research program 'Benchmark study for the Seismic Analysis and Testing of VVER Type NPPs'. The study reports the numerical simulation of the blast test for Paks and Kozloduy nuclear power plants beginning from the recorded free-field response and computing the structural response at various points inside the reactor building. The full-scale blast tests of the Paks and Kozloduy NPPs took place in December 1994 and in July 1996. During the tests the plants operated normally. The instrumentation for the tests consisted of 52 recording channels with 200 Hz sampling rate. Detonating 100 kg charges in 50-meter deep boreholes at 2.5-km distance from the plant carried out the blast tests. The 3D structural models for both reactor buildings were analyzed in the frequency domain. The number of modes extracted in both cases was about 500 and the cut-off frequency was 25 Hz. In the response history run the responses of the selected points were evaluated. The input values for response history run were the three components of the excitation, which were transformed from time domain to the frequency domain with the aid of Fourier transform. The analysis was carried out in frequency domain and responses were transferred back to time domain with inverse Fourier transform. The Paks and Kozloduy blast tests produced a wealth of information on the behavior of the nuclear power plant structures excited by blast type loads containing also the low frequency wave train if albeit with small energy content. The comparison of measured and calculated results gave information about the suitability of the selected analysis approach for the investigated blast type loading

Issues in the use of Weapons-Grade MOX Fuel in VVER-1000 Nuclear Reactors: Comparison of UO2 and MOX Fuels

Energy Technology Data Exchange (ETDEWEB)

Carbajo, J.J.

2005-05-27

The purpose of this report is to quantify the differences between mixed oxide (MOX) and low-enriched uranium (LEU) fuels and to assess in reasonable detail the potential impacts of MOX fuel use in VVER-1000 nuclear power plants in Russia. This report is a generic tool to assist in the identification of plant modifications that may be required to accommodate receiving, storing, handling, irradiating, and disposing of MOX fuel in VVER-1000 reactors. The report is based on information from work performed by Russian and U.S. institutions. The report quantifies each issue, and the differences between LEU and MOX fuels are described as accurately as possible, given the current sources of data.

The Paks Nuclear Power Station

International Nuclear Information System (INIS)

Erdosi, N.; Szabo, L.

1978-01-01

As the first stage in the construction of the Paks Nuclear Power Station, two units of 440 MW(e) each will be built. They are operated with two coolant loops each. The reactor units are VVER 440 type water-moderated PWR type heterogeneous power reactors designed in the Soviet Union and manufactured in Czechoslovakia. Each unit operates two Soviet-made K-220-44 steam turbines and Hungarian-made generators of an effective output of 220 MW. The output of the transformer units - also of Hungarian made - is 270 MVA. The radiation protection system of the nuclear power station is described. Protection against system failures is accomplished by specially designed equipment and security measures especially within the primary circuit. Some data on the power station under construction are given. (R.P.)

Top-Level Software for VVER-1000 In-core Monitoring System under Implementation of Expanded Nuclear Fuel Diversification Program in Ukraine

International Nuclear Information System (INIS)

Khalimonchuk, V.A.

2015-01-01

The paper considers the possibility and expediency of developing mathematical software for VVER-1000 ICMS in Ukraine. This mathematical software is among the most important conditions for implementation of the expanded nuclear fuel diversification program. The top-level software is to be developed based on SSTC own studies in the development of codes for power distribution recovery, which were successfully used previously for RBMK-1000 safety analysis

Test facility of the VVER-440 condensation-type pressure suppression system

International Nuclear Information System (INIS)

Wolff, H.; Arndt, S.

2004-01-01

Since the early nineties, GRS has supported regulatory authorities in Central and Eastern Europe in performing safety assessments of nuclear power plants. Especially studies of the condensation-type pressure suppression system of VVER-440/V-213-type plants have been important in this respect. Major steps in demonstrating complete functioning of the condensation-type pressure suppression system under accident conditions by experiments run in the Russian large scale test facility, BC V-213, have been completed in the past two years within the framework of various international experimental programs. The test results were used to validate specifically for power plants with VVER-400/V-213 reactors the COCOSYS GRS computer code, which is used in the safety assessments. The results of recalculations of the C02 EREC test, which simulates a break of a main steam pipe, demonstrate the present state of validation of COCOSYS for VVER condensation-type pressure suppression systems. (orig.) [de

VVER Reactor Safety in Eastern Europe and Former Soviet Union

Science.gov (United States)

Papadopoulou, Demetra

2012-02-01

VVER Soviet-designed reactors that operate in Eastern Europe and former Soviet republics have heightened international concern for years due to major safety deficiencies. The governments of countries with VVER reactors have invested millions of dollars toward improving the safety of their nuclear power plants. Most of these reactors will continue to operate for the foreseeable future since they provide urgently-needed electrical power. Given this situation, this paper assesses the radiological consequences of a major nuclear accident in Eastern Europe. The paper also chronicles the efforts launched by the international nuclear community to improve the safety of the reactors and notes the progress made so far through extensive collaborative efforts in Armenia, Bulgaria, the Czech Republic, Hungary, Kazakhstan, Lithuania, Russia, Slovakia, and Ukraine to reduce the risks of nuclear accidents. Western scientific and technical staff collaborated with these countries to improve the safety of their reactor operations by strengthening the ability of the regulator to perform its oversight function, installing safety equipment and technologies, investing time in safety training, and working diligently to establish an enduring safety culture. Still, continued safety improvement efforts are necessary to ensure safe operating practices and achieve timely phase-out of older plants.

Study on safety analysis of VVER-1200/V491 in scenario of Loss of Coolant Accidents along with partly failure of ECCS using RELAP5 code

International Nuclear Information System (INIS)

Hoang Minh Giang; Ha Thi Anh Dao; Hoang Tan Hung; Bui Thi Hoa; Nguyen Thi Tu Oanh; Dinh Anh Tuan; Pham Tuan Nam

2017-01-01

The advanced VVER-1200/V491 reactor designed with passive safety systems to deal with design extension conditions is primarily selected as priority candidate for Ninh Thuan 1 nuclear power plant project. So that, in order to enhance competence of nuclear safety and toward participation on review Safety Analysis Report (SAR) of Ninh Thuan nuclear Power project the study on safety analysis of VVER-1200/V491 in scenario of Loss of Coolant Accidents along with partly failure of ECCS is implemented. As requirement of the study, the input deck file of VVER-1200/V491 for RELAP5 and analysis report for some special case of LOCAs along with partly failure of ECCS are issued. (author)

Framatome advanced nuclear power-benefits for our clients from the new company

International Nuclear Information System (INIS)

Weber, P.

2001-01-01

Framatome ANP (Advanced Nuclear Power) merges the complementary strengths of two global nuclear industry leaders Framatome and Siemens - offering clients the best technological solutions for safe, reliable and economical plant performance. With a combined workforce of 13,300 skilled individuals, Framatome ANP is now the nuclear industry's leading supplier. Serving as Original Equipment Manufacturer (OEM) for more than 90 reactors that provide about 30% of the world's total installed nuclear power capacity, our experienced resources remain focused on the local needs of individual clients, wherever in the world they may be. The Company main business used to be turnkey construction of complete Nuclear Power plants, BWR and PWR capabilities, heavy equipment manufacturing, comprehensive I and C capabilities, and also expertise and knowledge of VVER. Framatome ANP will benefit in all of its fields of activity of the experience gained through Framatome and Siemens' collaboration on the next generation reactor, the EPR, as well as on steam generators replacements and or modernization of VVER. Framatome ANP nuclear fuel designs for both PWR and BWR plants provide innovative features and world-leading performance. Framatome ANP is organized according a matrix organization with: - 4 Business Groups (Project and Engineering, Service, Nuclear Fuel, Mechanical Equipment) - 3 Regional Divisions (Framatome Advanced Nuclear Power S.A.S., France; Framatome Advanced Nuclear Power GmbH, Germany; Framatome Advanced Nuclear Power Inc., USA). By 30th January 2001 Siemens Nuclear Power GmbH, founded in 2000 as successor of the Nuclear Division of Siemens Power Generation Group (KWU), was renamed to Framatome Advanced Nuclear Power GmbH forming the German part of the world wide acting company. Over the past 40 years 23 nuclear power plants all around the world - not only pressurized and boiling water reactors, but also two heavy-watermoderated reactors have been designed, constructed and

In-core nuclear fuel management optimization of VVER1000 using perturbation theory

International Nuclear Information System (INIS)

Hosseini, Mohammad; Vosoughi, Naser

2011-01-01

In-core nuclear fuel management is one of the most important concerns in the design of nuclear reactors. The two main goals in core fuel loading pattern design optimization are maximizing the core effective multiplication factor in order to extract the maximum energy, and keeping the local power peaking factor lower than a predetermined value to maintain fuel integrity. Because of the numerous possible patterns of the fuel assemblies in the reactor core, finding the best configuration is so important and complex. Different methods for optimization of fuel loading pattern in the core have been introduced so far. In this study, a software is programmed in C ⧣ language to find an order of the fuel loading pattern of the VVER-1000 reactor core using the perturbation theory. Our optimization method is based on minimizing the radial power peaking factor. The optimization process lunches by considering the initial loading pattern and the specifications of the fuel assemblies which are given as the input of the software. It shall be noticed that the designed algorithm is performed by just shuffling the fuel assemblies. The obtained results by employing the mentioned method on a typical reactor reveal that this method has a high precision in achieving a pattern with an allowable radial power peaking factor. (author)

Experience on KKNPP VVER 1000 MWe water chemistry

International Nuclear Information System (INIS)

Ganesh, S.; Selvaraj, S.; Balasubramanian, M.R.; Selvavinayagam, P.; Pillai, Suresh Kumar

2015-01-01

Kudankulam Nuclear Power Project consists of pressurized water reactor (VVER) 2 x 1000 MWe constructed in collaboration with Russian Federation at Kudankulam in Tirunelveli District, Tamilnadu. Unit - 1 attained criticality on July 13 th 2013 and the unit was synchronized to grid on 22 nd October 2013. This paper highlights experience gained on water chemistry regime for primary and secondary circuit. (author)

Development of an automated system of nuclear materials accounting for nuclear power stations with water-cooled, water-moderated reactors

International Nuclear Information System (INIS)

Babaev, N.S.

1981-06-01

The results of work carried out under IAEA Contract No. 2336/RB are described (subject: an automated system of nuclear materials accounting for nuclear power stations with water-cooled, water-moderated (VVER) reactors). The basic principles of an accounting system for this type of nuclear power plant are outlined. The general structure and individual units of the information computer program used to achieve automated accounting are described and instructions are given on the use of the program. A detailed example of its application (on a simulated nuclear power plant) is examined

Nuclear power and Imatran Voima in the future

International Nuclear Information System (INIS)

Numminen, K.

1995-01-01

As the owner of the Loviisa NPS with two VVER-440 units, Imatran Voima (IVO) has worked with nuclear power for more than twenty years. After the negative decision of the Finnish Parliament in 1993 there are no possibilities to build nuclear power in Finland in the near future. However, the preparation work for increasing the produced power of all four operating NPP's of Finland is going on. The emphasis in the work with new nuclear energy is on the supporting programs in Eastern Europe and the preparation of a building contract of a new NPS to China together with the Russians. With a new decision of the Finnish Parliament, the nuclear option could still be an important part of the future energy strategy of Finland. (orig.)

Diversification of the VVER fuel market in Eastern Europe and Ukraine

Energy Technology Data Exchange (ETDEWEB)

Kirst, Michael [Westinghouse EMEA, Brussels (Belgium); Benjaminsson, Ulf; Oenneby, Carina [Westinghouse Electric Sweden AB, Vaesteraes (Sweden)

2015-03-15

There are a total of 33 VVER active reactors in the EU and Ukraine, accounting for the largest percentage of the total electricity supply in the countries operating these. The responsible governments and utilities operating these units want too see an increased diversification of the nuclear fuel supply. Westinghouse is the only nuclear fuel producer outside Russia, which has taken the major steps to develop, qualify and manufacture VVER fuel designs - both for VVER-440 and VVER-1000 reactors. The company has delivered reloads of VVER-440 fuel to Loviisa 2 in Finland, VVER-1000 fuel for both the initial core and follow-on regions to Temelin 1-2 in the Czech Republic and more recently reloads of VVER-1000 fuel to South Ukraine 2-3. Technical challenges in form of mechanical interference with the resident fuel have been encountered in Ukraine, but innovative solutions have been developed and successfully implemented and today Ukraine has, for the first time in its history, a viable VVER-1000 fuel design alternative, representing a tremendous lever in energy security for the country.

Radiolysis of the VVER-1000 reactor coolant: An experimental study and mathematical modeling

International Nuclear Information System (INIS)

Arkhipov, O.P.; Bugaenko, V.L.; Kabakchi, S.A.

1995-01-01

Variations in the composition of the coolant for the primary circuit of a VVER-1000 reactor of the Kalinin nuclear power plant upon transition from power-level operation to shutdown was studied experimentally. The data obtained were used for verification of the MORAVA-H2 program developed earlier for simulation of the coolant state in pressurized-water power reactors

PMK-2, the First Integral Thermal-Hydraulics Tests for the Safety Evaluation of VVER-440/213 Nuclear Power Plants

Directory of Open Access Journals (Sweden)

Gy. Ézsöl

2012-01-01

Full Text Available The PMK-2 facility is a full-pressure thermal-hydraulic model of the primary and partly the secondary circuit of the VVER-type units of Paks NPP. The facility was the first integral-type facility for VVERs. The PMK-2 was followed later by the PACTEL (for VVER-440, the ISB, and PSB for VVER-1000. Since the startup of the facility in 1985, 55 experiments have been performed primarily in international frameworks with the participation of experts from 29 European and overseas countries forming a scientific school to better understand VVER system behaviour and reach a high level of modelling of accident sequences. The ATHLET, CATHARE, and RELAP5 codes have been validated including both qualitative and quantitative assessments. The former was almost exclusively applied to the early phase of validation by integral experiments, while the quantitative assessments have been performed by the Fast Fourier Transform Based Method. Paper gives comprehensive information on the design features of PMK-2 facility with a special respect to the representativeness of phenomena, the experiments performed, and the results of the validation of ATHLET, CATHARE, and RELAP5 codes. Safety significance of the PMK-2 projects is also discussed.

PMK-2, the First Integral Thermal-Hydraulics Tests for the Safety Evaluation of VVER-440/213 Nuclear Power Plants

International Nuclear Information System (INIS)

Ezsol, G.; Perneczky, L.; Szabados, L.; Toth, I.

2012-01-01

The PMK-2 facility is a full-pressure thermal-hydraulic model of the primary and partly the secondary circuit of the VVER-type units of Paks NPP. The facility was the first integral-type facility for VVERs. The PMK-2 was followed later by the PACTEL (for VVER-440), the ISB, and PSB for VVER-1000. Since the startup of the facility in 1985, 55 experiments have been performed primarily in international frameworks with the participation of experts from 29 European and overseas countries forming a scientific school to better understand VVER system behaviour and reach a high level of modelling of accident sequences. The ATHLET, CATHARE, and RELAP5 codes have been validated including both qualitative and quantitative assessments. The former was almost exclusively applied to the early phase of validation by integral experiments, while the quantitative assessments have been performed by the Fast Fourier Transform Based Method. Paper gives comprehensive information on the design features of PMK-2 facility with a special respect to the representativeness of phenomena, the experiments performed, and the results of the validation of ATHLET, CATHARE, and RELAP5 codes. Safety significance of the PMK-2 projects is also discussed

Safety enhancement concept for NPP of new generation with VVER reactors

International Nuclear Information System (INIS)

Bezlepkin, V.; Kukhtevich, I.; Semashko, S.; Svetlov, S.; Solodovnikov, A.

2004-01-01

With the present day conditions, in order to successfully promote new NPP designs in the electric power markets, it is necessary to ensure enhanced technical/economic performances provided that international safety requirements are properly adhered to. When compared with high-powered nuclear power plants, NPP VVER-640 design (medium powered) possesses a number of advantages for the regions with undeveloped energy systems. Reduced specific energy intensity of the core adopted in this type of reactor allows to ensure the emergency cooldown of the reactor plant by passive means and to minimize the 'human factor' risk and external effects and provide sound substantiations as to how to retain corium inside RPV in case of severe accidents. At the same time, high-powered NPPs seem to be promising for regions with developed energy systems. Among such designs, NPP VVER-1000 and VVER-1500 designs are the most desirable. Configuration of new generation NPP with VVER-1500 is to be selected based on the gained experience in designing NPPs of previous generations considering the latest safety requirements and situation in the domestic and global energy markets for the time being and in the short run. Recent IAEA publications and latest EUR requirements insist that the following key safety indices should be established for new NPP designs: - aggregated frequency of core melting is 10 -6 (1/year); - frequency of maximum accident release is 10 -7 (1/year). To meet the aforementioned criteria, it is necessary to implement some safety assurance principles recommended by IAEA (in-depth defence, single failure, redundancy, diversity, etc.), application of deterministic and probabilistic methods for selection of safety assurance activities and means and use of reasonable combination of active and passive systems. Application of VVER-640 concept to high-powered NPPs seems to be a formidable task due to a number of reasons, namely, it is quite difficult to carry out cooldown process

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)

Primary water chemistry for NPP with VVER-TOI

International Nuclear Information System (INIS)

Susakin, S.N.; Brykov, S.I.; Zadonsky, N.V.; Bystrova, O.S.

2012-09-01

Nowadays within the framework of development of the nuclear power industry in Russia the VVER-TOI reactor is under designing (Standard optimized design). The given design provides for improvement of operation safety level, of technical-economic, operational and load-follow characteristics, and for the raise of competitive capacity of reactor plant and NPP as a whole. In VVER-TOI reactor plant design the primary water chemistry has been improved considering operation experience of VVER reactor plants and a possibility of RP operation under load-follow modes from the viewpoint of meeting the following requirements: - suppression of generation of oxidizing radiolytic products under power operation; - assurance of corrosion resistance of structural materials of equipment and pipelines throughout the NPP design service life; - minimization of deposits on surfaces of the reactor core fuel rods and on heat exchange surface of steam generators; - minimization of accumulation of activated corrosion products; - minimization of the amount of radioactive processing waste. In meeting these requirements an important role is devoted to suppression of generation of oxidizing radiolytic products owing to accumulation of hydrogen in the primary coolant. At NPP with VVER-1000 reactor the ammonia-potassium water chemistry is used wherein the hydrogen accumulation is provided at the expense of ammonia proportioning. Usage of ammonia leads to generation of additional amount of radioactive processing waste and to increased irregularity of maintaining the water chemistry under the daily load-follow modes. In VVER TOI design the primary water chemistry is improved by replacing the proportioning of ammonia with the proportioning of gaseous hydrogen. Different process schemes were considered that provide for a possibility of hydrogen accumulation and maintaining owing to direct proportioning of gaseous hydrogen. The obtained results showed that transition to the potassium water chemistry

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)

Evaluating the consequences of loss of flow accident for a typical VVER-1000 nuclear reactor

Energy Technology Data Exchange (ETDEWEB)

Mirvakili, S.M.; Safaei, S. [Shiraz Univ., Shiraz (Iran, Islamic Republic of). Dept. of Nuclear Engineering, School of Mechanical Engineering; Faghihi, F. [Shiraz Univ., Shiraz (Iran, Islamic Republic of). Safety Research Center

2010-07-01

The loss of coolant flow in a nuclear reactor can result from a mechanical or electrical failure of the coolant pump. If the reactor is not tripped promptly, the immediate effect is a rapid increase in coolant temperature, decrease in minimum departure from nucleate boiling ratio (DNBR) and fuel damage. This study evaluated the shaft seizure of a reactor coolant pump in a VVER-1000 nuclear reactor. The locked rotor results in rapid reduction of flow through the affected reactor coolant loop and in turn leads to an increase in the primary coolant temperature and pressure. The analysis was conducted with regard for superimposing loss of power to the power plant at the initial accident moment. The required transient functions of flow, pressure and power were obtained using system transient calculations applied in COBRA-EN computer code in order to calculate the overall core thermal-hydraulic parameters such as temperature, critical heat flux and DNBR. The study showed that the critical period for the locked rotor accident is the first few seconds during which the maximum values of pressure and temperature are reached. 10 refs., 1 tab., 3 figs.

Vver-1000 Mox core computational benchmark

International Nuclear Information System (INIS)

2006-01-01

The NEA Nuclear Science Committee has established an Expert Group that deals with the status and trends of reactor physics, fuel performance and fuel cycle issues related to disposing of weapons-grade plutonium in mixed-oxide fuel. The objectives of the group are to provide NEA member countries with up-to-date information on, and to develop consensus regarding, core and fuel cycle issues associated with burning weapons-grade plutonium in thermal water reactors (PWR, BWR, VVER-1000, CANDU) and fast reactors (BN-600). These issues concern core physics, fuel performance and reliability, and the capability and flexibility of thermal water reactors and fast reactors to dispose of weapons-grade plutonium in standard fuel cycles. The activities of the NEA Expert Group on Reactor-based Plutonium Disposition are carried out in close co-operation (jointly, in most cases) with the NEA Working Party on Scientific Issues in Reactor Systems (WPRS). A prominent part of these activities include benchmark studies. At the time of preparation of this report, the following benchmarks were completed or in progress: VENUS-2 MOX Core Benchmarks: carried out jointly with the WPRS (formerly the WPPR) (completed); VVER-1000 LEU and MOX Benchmark (completed); KRITZ-2 Benchmarks: carried out jointly with the WPRS (formerly the WPPR) (completed); Hollow and Solid MOX Fuel Behaviour Benchmark (completed); PRIMO MOX Fuel Performance Benchmark (ongoing); VENUS-2 MOX-fuelled Reactor Dosimetry Calculation (ongoing); VVER-1000 In-core Self-powered Neutron Detector Calculational Benchmark (started); MOX Fuel Rod Behaviour in Fast Power Pulse Conditions (started); Benchmark on the VENUS Plutonium Recycling Experiments Configuration 7 (started). This report describes the detailed results of the benchmark investigating the physics of a whole VVER-1000 reactor core using two-thirds low-enriched uranium (LEU) and one-third MOX fuel. It contributes to the computer code certification process and to the

Severe accident management development program for VVER-1000 and VVER-440/213 based on the westinghouse owners group approach

International Nuclear Information System (INIS)

Felix, E.; Dessars, N.

2003-01-01

The development of the Westinghouse Owners Group Severe Accident Management Guidelines (WOG SAMG) between 1991 and 1994 was initiated in response to the U.S. Nuclear Regulatory Commission (NRC) requirement for addressing the regulatory severe accident concerns. Hence, the WOG SAMG is designed to interface with other existing procedures at the plant and is used in accident sequences that have progressed to the point where these other procedures are not applicable any longer, i.e. following core damage. The primary purpose of the WOG SAMG is to reach a controlled stable state, which can be declared when fission product releases are controlled, challenges to the confinement fission product boundary have been mitigated, and adequate heat removal is provided to the core and the containment. Although the WOG SAMG is a generic severe accident management guidance developed for use by the entirety of the operating Westinghouse PWR plants, provisions have been made in their development to address specific features of individual plants such as confinement type and the feasibility of reactor cavity flooding. Similarly, the generic SAMG does not address unique plant features and equipment, but rather allows for consideration of plant specific features and strategies. This adaptable approach has led to several SAMG development programs for VVER-1000 and VVER-440 type of power plants, under Westinghouse' s lead. The first of these programs carried out to completion was for Temelin NPP - VVER-1000 - in the first quarter of 2003. Other ongoing programs aim at providing a similar work for VVER-440 design, namely Dukovany, Mochovce and Bohunice NPPs. The challenge of adapting the existing generic WOG material to plants other than PWRs mainly arises for VVER-440 because of important differences in confinement design, making it more vulnerable to ex-vessel phenomena such as hydrogen burn. Also, for both eastern designs, cavity flooding strategy requires special consideration and

Nuclear power: 2006 world report - evaluation

International Nuclear Information System (INIS)

Anon.

2007-01-01

Last year, 2006, 437 nuclear power plants were available for power supply in 31 countries, 7 plants less than in 2005. One unit was commissioned for the first time, 8 nuclear power plants were decommissioned for good in 2006. At a cumulated gross power of 389,488 MWe and a cumulated net power of 370,441 MWe, respectively, worldwide nuclear generating capacity has reached a high level so far. Nine different reactor lines are operated in commercial plants: PWR, PWR-VVER, BWR, CANDU, D 2 O PWR, GCR, AGR, LWGR, and LMFBR. Light water reactors (PWR and BWR) continue to top the list with 358 plants. By the end of the year, 10 countries operated 29 nuclear power plants with an aggregate gross power of 25,367 MWe and an aggregate net power of 23,953 MWe, respectively. Of these, 21 are light water reactors, 5 are CANDU-type reactors, 2 are fast breeder and 1 a LWGR. 123 commercial reactors with an aggregate power in excess of 5 MWe have so far been decommissioned in 19 countries. Most of them are prototype plants of low power. About 70% of the nuclear power plants in operation, namely 304 plants, were commissioned in the eighties and nineties. The energy availability and operating availability factors of the nuclear power plants again reached peak levels: 82% for energy availability, and 83% for operating availability. The 4 nuclear power plants in Finland continue to be in the lead worldwide with a cumulated average operating capacity factor of 94%. (orig.)

Nuclear power. 2008 world report - evaluation

International Nuclear Information System (INIS)

Anon.

2010-01-01

In 2008, 438 nuclear power plants were available for power supply in 31 countries, 1 plant less than in 2007. No unit was commissioned for the first time, 1 nuclear power plant was decommissioned for good in 2008. At a cumulated gross power of 392,597 MWe and a cumulated net power of 372,170 MWe, respectively, worldwide nuclear generating capacity has reached a high level. Nine different reactor lines are operated in commercial plants: PWR, PWR-VVER, BWR, CANDU, D2O PWR, GCR, AGR, LWGR, and LMFBR. Light water reactors (PWR and BWR) continue to top the list with 358 plants. By the end of 2008, in 14 countries 43 nuclear power plants with an aggregate gross power of 39,211 MWe and an aggregate net power of 36,953 MWe were under construction. Of these, 37 are light water reactors, 3 are CANDU-type reactors, 2 are fast breeder and 1 D2O-PWR. 124 commercial reactors with an aggregate power in excess of 5 MWe have so far been decommissioned in 19 countries. Most of them are prototype plants of low power. About 70% of the nuclear power plants in operation, namely 304 plants, were commissioned in the eighties and nineties. The energy availability and operating availability factors of the nuclear power plants reached good levels: 80.80% for operating availability and 80,00% for energy availability. The four nuclear power plants in Finland continuecontinue to be in the lead worldwide with a cumulated average operating capacity factor of 91,60%. (orig.)

Almost twenty years' search of transuranium isotopes in effluents discharged to air from nuclear power plants with VVER reactors.

Science.gov (United States)

Hölgye, Z; Filgas, R

2006-04-01

Airborne effluents of 5 stacks (stacks 1-5) of three nuclear power plants, with 9 pressurized water reactors VVER of 4,520 MWe total power, were searched for transuranium isotopes in different time periods. The search started in 1985. The subject of this work is a presentation of discharge data for the period of 1998-2003 and a final evaluation. It was found that 238Pu, 239,240Pu, 241Am, 242Cm, and 244Cm can be present in airborne effluents. Transuranium isotope contents in most of the quarterly effluent samples from stacks 2, 4 and 5 were not measurable. Transuranium isotopes were present in the effluents from stack l during all 9 years of the study and from stack 3 since the 3rd quarter of 1996 as a result of a defect in the fuel cladding. A relatively high increase of transuranium isotopes in effluents from stack 3 occurred in the 3rd quarter of 1999, and a smaller increase occurred in the 3rd quarter of 2003. In each instance 242Cm prevailed in the transuranium isotope mixtures. 238Pu/239,240Pu, 241Am/239,240Pu, 242Cm/239,240Pu, and 244Cm/239,240Pu ratios in fuel for different burn-up were calculated, and comparison of these ratios in fuel and effluents was performed.

Safety classification of items in Tianwan Nuclear Power Plant

International Nuclear Information System (INIS)

Sun Yongbin

2005-01-01

The principle of integrality, moderation and equilibrium should be considered in the safety classification of items in nuclear power plant. The basic ways for safety classification of items is to classify the safety function based on the effect of the outside enclosure damage of the items (parts) on the safety. Tianwan Nuclear Power Plant adopts Russian VVER-1000/428 type reactor, it safety classification mainly refers to Russian Guidelines and standards. The safety classification of the electric equipment refers to IEEE-308(80) standard, including 1E and Non 1E classification. The safety classification of the instrumentation and control equipment refers to GB/T 15474-1995 standard, including safety 1E, safety-related SR and NC non-safety classification. The safety classification of Tianwan Nuclear Power Plant has to be approved by NNSA and satisfy Chinese Nuclear Safety Guidelines. (authors)

Informational system to assist decision making at spent nuclear fuel transportation from VVER-440, VVER-1000 and RBMK-1000 nuclear power plants

International Nuclear Information System (INIS)

Kuryndin, A.V.; Kirkin, A.M.; Stroganov, A.A.

2012-01-01

The developed informational system provides an automated estimations of nuclear and radiation safety parameters during spent nuclear fuel transportation from WWER-440 and WWER-1000 and RBMK-1000 nuclear power plants to the nuclear fuel cycle facilities, and allows us to determine the optimum cask loading from the dose rates distribution outside of protection point of view [ru

Analytical validation of operator actions in case of primary to secondary leakage for VVER-1000/V320

Energy Technology Data Exchange (ETDEWEB)

Andreeva, M., E-mail: m_andreeva@inrne.bas.bg; Groudev, P., E-mail: pavlinpg@inrne.bas.bg; Pavlova, M., E-mail: pavlova@inrne.bas.bg

2015-12-15

Highlights: • We validate operator actions in case of primary to secondary leakage. • We perform four scenarios related to SGTR accident for VVER-1000/V320. • The reference power plant for the analyses is Unit 6 at Kozloduy NPP. • The RELAP5/MOD 3.2 computer code is used in performing the analyses. • The analyses confirm the effectiveness of operator actions during PRISE. - Abstract: This paper presents the results of analytical validation of operator actions in case of “Steam Generator Tube Rupture” (SGTR) for VVER-1000/V320 units at Kozloduy Nuclear Power Plant (KNPP), done during the development of Symptom Based Emergency Operating Procedures (SB EOPs) for this plant. The purpose of the analyses is to demonstrate the ability to terminate primary to secondary leakage and to indicate an effective strategy for preventing secondary leakage to the environment and in this way to prevent radiological release to the environment. Following depressurization and cooldown of reactor coolant system (RCS) with isolation of the affected steam generator (SG), in these analyses are validated options for post-SGTR cooldown by: • back up filling the ruptured SG; • using letdown system in the affected SG and • by opening Fast Acting Isolation Valve (FAIV) and using Steam Dump Facility to the Condenser (BRU-K). The results of the thermal-hydraulic analyses have been used to assist KNPP specialists in analytical validation of EOPs. The RELAP5/MOD3.2 computer code has been used for the analyses in a VVER-1000 Nuclear Power Plant (NPP) model. A model of VVER-1000 based on Unit 6 of Kozloduy NPP has been developed for the thermal-hydraulics code RELAP5/MOD3.2 at the Institute for Nuclear Research and Nuclear Energy – Bulgarian Academy of Sciences (INRNE-BAS). This paper is possible through the participation of leading specialists from KNPP.

Water chemistry experiences with VVERs at Kudankulam

International Nuclear Information System (INIS)

Rout, D.; Upadhyaya, T.C.; Ravindranath; Selvinayagam, P.; Sundar, R.S.

2015-01-01

Kudankulam Nuclear Power Project - 1 and 2 (Kudankulam NPP - 1 and 2) are pressurised water cooled VVERs of 1000 MWe each. Kudankulam NPP Unit - 1 is presently on its first cycle of operation and Kudankulam NPP Unit - 2 is on the advanced stage of commissioning with the successful completion of hot run related Functional tests. Water Chemistry aspects during various phases of commissioning of Kudankulam NPP Unit - 1 such as Hot Run, Boric acid flushing, initial fuel Loading (IFL), First approach to Criticality (FAC) are discussed. The main objectives of the use of controlled primary water chemistry programme during the hot functional tests are reviewed. The importance of the relevant water chemistry parameters were ensured to have the quality of the passive layer formed on the primary coolant system surfaces. The operational experiences during the 1 st cycle of operation of primary water chemistry, radioactivity transport and build-up are presented. The operational experience of some VVER units in the field of the primary water chemistry, radioactivity transport and build-up are presented as a comparison to VVER at Kudankulam NPP. The effects of the initial passivated layer formed on metal surfaces during hot run, activated corrosion products levels in the primary coolant under controlled water chemistry regime and the contamination/radiation situation are discussed. This report also includes the water chemistry related issues of secondary water systems. (author)

Analysis of VVER-1000 large and small break LOCA experiments with RELAP5/MOD3.2

International Nuclear Information System (INIS)

Rychkov, M.; Chikkanagoudar, U.; Sehgal, B.R.

2004-01-01

A RELAP5 model for the analysis of the PSB-VVER test facility was developed by EREC in Russia. The PSB-VVER is a large-scale integral test facility to model the VVER-1000 type NPP. The volume and power scale in this test facility is 1:300 and the elevation scale is 1:1, which corresponds to the elevation mark of the reactor prototype. At the Division of Nuclear Safety, we have modified the PSB-VVER facility's RELAP5 model in order to analyze two of the transient tests performed on the PSB-VVER facility, which serve as the validation matrix described by NEA/CSNI. The objective of the work conducted was to validate the results obtained from RELAP5's calculation with the supplied experimental data from the PSB-VVER test facility. Two accident scenarios have been calculated and analyzed. After being verified against the '11% UP LOCA' test data, the RELAP5/MOD3.2 model was used for a so-called 'blind' transient calculation of the test '2*25% HL LOCA' and the results obtained were compared with the experimental data provided after the calculation. From the results of the qualitative and quantitative comparison of the 2 test calculations and the experimental data, we can state that the RELAP5/MOD3.2 code gives a satisfactory modeling of the PSB-VVER facility' thermal hydraulic phenomena

Validation of containment thermal hydraulic computer codes for VVER reactor

Energy Technology Data Exchange (ETDEWEB)

Jiri Macek; Lubomir Denk [Nuclear Research Institute Rez plc Thermal-Hydraulic Analyses Department CZ 250 68 Husinec-Rez (Czech Republic)

2005-07-01

Full text of publication follows: The Czech Republic operates 4 VVER-440 units, two VVER-1000 units are being finalized (one of them is undergoing commissioning). Thermal-hydraulics Department of the Nuclear Research Institute Rez performs accident analyses for these plants using a number of computer codes. To model the primary and secondary circuits behaviour the system codes ATHLET, CATHARE, RELAP, TRAC are applied. Containment and pressure-suppression system are modelled with COCOSYS and MELCOR codes, the reactor power calculations (point and space-neutron kinetics) are made with DYN3D, NESTLE and CDF codes (FLUENT, TRIO) are used for some specific problems.An integral part of the current Czech project 'New Energy Sources' is selection of a new nuclear source. Within this and the preceding projects financed by the Czech Ministry of Industry and Trade and the EU PHARE, the Department carries and has carried out the systematic validation of thermal-hydraulic and reactor physics computer codes applying data obtained on several experimental facilities as well as the real operational data. One of the important components of the VVER 440/213 NPP is its containment with pressure suppression system (bubble condenser). For safety analyses of this system, computer codes of the type MELCOR and COCOSYS are used in the Czech Republic. These codes were developed for containments of classic PWRs or BWRs. In order to apply these codes for VVER 440 systems, their validation on experimental facilities must be performed.The paper provides concise information on these activities of the NRI and its Thermal-hydraulics Department. The containment system of the VVER 440/213, its functions and approaches to solution of its safety is described with definition of acceptance criteria. A detailed example of the containment code validation on EREC Test facility (LOCA and MSLB) and the consequent utilisation of the results for a real NPP purposes is included. An approach to

Meeting the physics design challenges of modern LWRs being inducted into the Indian nuclear power programme

International Nuclear Information System (INIS)

Jagannathan, V.; Pal, Usha; Karthikeyan, R.; Raj, Devesh; Srivastava, Argala; Khan, Suhail Ahmad

2007-01-01

Indian nuclear power programme started with the two Boiling Water Reactors (BWR) of 210 MWe capacity at Tarapur. Two VVER-1000 MWe reactors which are Pressurized Water Reactors (PWR) of Russian design are being constructed at Kudankulam, Tamilnadu and are expected to be commissioned by end 2008. There may be also a possibility of inducting some western PWRs in future. These reactors belong to the category of light water reactors (LWR). The LWRs are compact and have complex physical characteristics distinctly different from those of the Pressurized Heavy Water Reactors (PHWR) which, currently form the mainstay of our indigenous nuclear power programme. The physics design and analysis capability for the modern LWRs (BWR, PWR and VVER) has been developed at Light Water Reactors Physics Section, BARC. This paper presents the current state of art in this key technology area to meet the physics design and operation challenges when LWRs would be inducted in a major way into the Indian nuclear power programme and commence operating in the coming decades. (author)

System analysis of nuclear safety of VVER reactor with MOX fuel

Energy Technology Data Exchange (ETDEWEB)

Klimov, A.D.; Zharkov, V.P.; Suslov, I.R. [Russia, Moscow Malaya Krasnoselskaya St. (Russian Federation); Boyarinov, V.F.; Kevrolev, V.V.; Tchibinyaev, A.V.; Tsibulskiy, V.F. [RRC KI, Russia, Moscow (Russian Federation); Kochurov, B.P. [ITEP, Russia, Moscow (Russian Federation); Giovanni, B. [NFPSC, FRAMATOME (France)

2005-07-01

The report presents a short summary of the results achieved in the ISTC (International Science and Technology Center) project 'System analysis of nuclear safety of VVER reactor with MOX fuel' (April 2005). The studies within the project are of a systematic character and include the solutions of 15 tasks. The report gives an overview of the major blocks of these tasks: neutron transport equation solution; calculations of isotopic vectors, analysis of the impact of uncertainties on predicted reactor functionals. The calculation methods, the verification results and the corresponding codes are briefly described. (authors)

Analysis of changes in the fuel component of the cost of electricity in the transition to a closed fuel cycle in nuclear power system

International Nuclear Information System (INIS)

Gurin, Andrey V.; Alekseev, P.N.

2017-01-01

This paper presents a study of scenarios of transition to a closed fuel cycle in the system of nuclear power, built basing on resource availability requirements at the stage of full life-cycle reactors. Conventionally, there are three main scenarios for the development of nuclear energy: with VVER reactors operating in an open fuel cycle; with VVER reactors operating in a closed fuel cycle; and co-operating VVER and BN, operating in a closed fuel cycle. For the considered scenarios, a quantitative estimation of change in time of material balances were performed, including spent fuel balance, balance of plutonium, reprocessed and depleted uranium, radioactive waste, and the analysis of the fuel component of the cost of electricity.

Analysis of changes in the fuel component of the cost of electricity in the transition to a closed fuel cycle in nuclear power system

Energy Technology Data Exchange (ETDEWEB)

Gurin, Andrey V. [National Research Centre ' ' Kurchatov Institute' ' , Moscow (Russian Federation); Alekseev, P.N.

2017-09-15

This paper presents a study of scenarios of transition to a closed fuel cycle in the system of nuclear power, built basing on resource availability requirements at the stage of full life-cycle reactors. Conventionally, there are three main scenarios for the development of nuclear energy: with VVER reactors operating in an open fuel cycle; with VVER reactors operating in a closed fuel cycle; and co-operating VVER and BN, operating in a closed fuel cycle. For the considered scenarios, a quantitative estimation of change in time of material balances were performed, including spent fuel balance, balance of plutonium, reprocessed and depleted uranium, radioactive waste, and the analysis of the fuel component of the cost of electricity.

Development of a VVER-1000 core loading pattern optimization program based on perturbation theory

International Nuclear Information System (INIS)

Hosseini, Mohammad; Vosoughi, Naser

2012-01-01

Highlights: ► We use perturbation theory to find an optimum fuel loading pattern in a VVER-1000. ► We provide a software for in-core fuel management optimization. ► We consider two objectives for our method (perturbation theory). ► We show that perturbation theory method is very fast and accurate for optimization. - Abstract: In-core nuclear fuel management is one of the most important concerns in the design of nuclear reactors. Two main goals in core fuel loading pattern design optimization are maximizing the core effective multiplication factor in order to extract the maximum energy, and keeping the local power peaking factor lower than a predetermined value to maintain the fuel integrity. Because of the numerous possible patterns of fuel assemblies in the reactor core, finding the best configuration is so important and challenging. Different techniques for optimization of fuel loading pattern in the reactor core have been introduced by now. In this study, a software is programmed in C language to find an order of the fuel loading pattern of a VVER-1000 reactor core using the perturbation theory. Our optimization method is based on minimizing the radial power peaking factor. The optimization process launches by considering an initial loading pattern and the specifications of the fuel assemblies which are given as the input of the software. The results on a typical VVER-1000 reactor reveal that the method could reach to a pattern with an allowed radial power peaking factor and increases the cycle length 1.1 days, as well.

Implementation of New Reactivity Measurement System and New Reactor Noise Analysis Equipment in a VVER-440 Nuclear Power Plant

Science.gov (United States)

Vegh, János; Kiss, Sándor; Lipcsei, Sándor; Horvath, Csaba; Pos, István; Kiss, Gábor

2010-10-01

The paper deals with two recently developed, high-precision nuclear measurement systems installed at the VVER-440 units of the Hungarian Paks NPP. Both developments were motivated by the reactor power increase to 108%, and by the planned plant service time extension. The first part describes the RMR start-up reactivity measurement system with advanced services. High-precision picoampere meters were installed at each reactor unit and measured ionization chamber current signals are handled by a portable computer providing data acquisition and online reactivity calculation service. Detailed offline evaluation and analysis of reactor start-up measurements can be performed on the portable unit, too. The second part of the paper describes a new reactor noise diagnostics system using state-of-the-art data acquisition hardware and signal processing methods. Details of the new reactor noise measurement evaluation software are also outlined. Noise diagnostics at Paks NPP is a standard tool for core anomaly detection and for long-term noise trend monitoring. Regular application of these systems is illustrated by real plant data, e.g., results of standard reactivity measurements during a reactor startup session are given. Noise applications are also illustrated by real plant measurements; results of core anomaly detection are presented.

An experimental investigation of 1% SBLOCA on PSB-VVER test facility

Energy Technology Data Exchange (ETDEWEB)

Lipatov, I.A.; Dremin, G.I.; Galtchanskaia, S.A.; Gorbunov, Yu.S. [Electrogorsk Research and Engineering Center, EREC, Electrogorsk (Russian Federation); Elkin, I.V. [Russian Research Centre Kurchatov Inst., Moscow (Russian Federation)

2001-07-01

The paper presents the results of the three tests carried out in the PSB-VVER large-scale integral test facility. The PSB-VVER test facility is a four loop, full pressure scaled down model bearing structural similarities to the primary system of the NRP with VVER-1000 Russian design reactor. Volume-power scale is 1/300 while elevation scale is 1/1. (orig.)

Burnup Estimation of Rhodium Self-Powered Neutron Detector Emitter in VVER Reactor Core Using Monte Carlo Simulations

OpenAIRE

Khrutchinsky, А. А.; Kuten, S. A.; Babichev, L. F.

2011-01-01

Estimation of burn-up in a rhodium-103 emitter of self-powered neutron detector in VVER-1000 reactor core has been performed using Monte Carlo simulations within approximation of a constant neutron flux.

Adaptive Neural Network Algorithm for Power Control in Nuclear Power Plants

International Nuclear Information System (INIS)

Husam Fayiz, Al Masri

2017-01-01

The aim of this paper is to design, test and evaluate a prototype of an adaptive neural network algorithm for the power controlling system of a nuclear power plant. The task of power control in nuclear reactors is one of the fundamental tasks in this field. Therefore, researches are constantly conducted to ameliorate the power reactor control process. Currently, in the Department of Automation in the National Research Nuclear University (NRNU) MEPhI, numerous studies are utilizing various methodologies of artificial intelligence (expert systems, neural networks, fuzzy systems and genetic algorithms) to enhance the performance, safety, efficiency and reliability of nuclear power plants. In particular, a study of an adaptive artificial intelligent power regulator in the control systems of nuclear power reactors is being undertaken to enhance performance and to minimize the output error of the Automatic Power Controller (APC) on the grounds of a multifunctional computer analyzer (simulator) of the Water-Water Energetic Reactor known as Vodo-Vodyanoi Energetichesky Reaktor (VVER) in Russian. In this paper, a block diagram of an adaptive reactor power controller was built on the basis of an intelligent control algorithm. When implementing intelligent neural network principles, it is possible to improve the quality and dynamic of any control system in accordance with the principles of adaptive control. It is common knowledge that an adaptive control system permits adjusting the controller’s parameters according to the transitions in the characteristics of the control object or external disturbances. In this project, it is demonstrated that the propitious options for an automatic power controller in nuclear power plants is a control system constructed on intelligent neural network algorithms. (paper)

Development and qualification of a thermal-hydraulic nodalization for modeling station blackout accident in PSB-VVER test facility

Energy Technology Data Exchange (ETDEWEB)

Saghafi, Mahdi [Department of Energy Engineering, Sharif University of Technology, Azadi Avenue, Tehran (Iran, Islamic Republic of); Ghofrani, Mohammad Bagher, E-mail: ghofrani@sharif.edu [Department of Energy Engineering, Sharif University of Technology, Azadi Avenue, Tehran (Iran, Islamic Republic of); D’Auria, Francesco [San Piero a Grado Nuclear Research Group (GRNSPG), University of Pisa, Via Livornese 1291, San Piero a Grado, Pisa (Italy)

2016-07-15

Highlights: • A thermal-hydraulic nodalization for PSB-VVER test facility has been developed. • Station blackout accident is modeled with the developed nodalization in MELCOR code. • The developed nodalization is qualified at both steady state and transient levels. • MELCOR predictions are qualitatively and quantitatively in acceptable range. • Fast Fourier Transform Base Method is used to quantify accuracy of code predictions. - Abstract: This paper deals with the development of a qualified thermal-hydraulic nodalization for modeling Station Black-Out (SBO) accident in PSB-VVER Integral Test Facility (ITF). This study has been performed in the framework of a research project, aiming to develop an appropriate accident management support tool for Bushehr nuclear power plant. In this regard, a nodalization has been developed for thermal-hydraulic modeling of the PSB-VVER ITF by MELCOR integrated code. The nodalization is qualitatively and quantitatively qualified at both steady-state and transient levels. The accuracy of the MELCOR predictions is quantified in the transient level using the Fast Fourier Transform Base Method (FFTBM). FFTBM provides an integral representation for quantification of the code accuracy in the frequency domain. It was observed that MELCOR predictions are qualitatively and quantitatively in the acceptable range. In addition, the influence of different nodalizations on MELCOR predictions was evaluated and quantified using FFTBM by developing 8 sensitivity cases with different numbers of control volumes and heat structures in the core region and steam generator U-tubes. The most appropriate case, which provided results with minimum deviations from the experimental data, was then considered as the qualified nodalization for analysis of SBO accident in the PSB-VVER ITF. This qualified nodalization can be used for modeling of VVER-1000 nuclear power plants when performing SBO accident analysis by MELCOR code.

Shaping of the axial power density distribution in the core to minimize the vapor volume fraction at the outlet of the VVER-1200 fuel assemblies

Energy Technology Data Exchange (ETDEWEB)

Savander, V. I.; Shumskiy, B. E., E-mail: borisshumskij@yandex.ru [National Research Nuclear University MEPhI (Russian Federation); Pinegin, A. A. [National Research Center Kurchatov Institute (Russian Federation)

2016-12-15

The possibility of decreasing the vapor fraction at the VVER-1200 fuel assembly outlet by shaping the axial power density field is considered. The power density field was shaped by axial redistribution of the concentration of the burnable gadolinium poison in the Gd-containing fuel rods. The mathematical modeling of the VVER-1200 core was performed using the NOSTRA computer code.

SCORPIO - VVER core surveillance system

International Nuclear Information System (INIS)

Hornaes, A.; Bodal, T.; Sunde, S.

1998-01-01

The Institutt for energiteknikk has developed the core surveillance system SCORPIO, which has two parallel modes of operation: the Core Follow Mode and the Predictive Mode. The main motivation behind the development of SCORPIO is to make a practical tool for reactor operators, which can increase the quality and quantity of information presented on core status and dynamic behavior. This can first of all improve plant safety, as undesired core conditions are detected and prevented. Secondly, more flexible and efficient plant operation is made possible. The system has been implemented on western PWRs, but the basic concept is applicable to a wide range of reactors including VVERs. The main differences between VVERs and typical western PWRs with respect to core surveillance requirements are outlined. The development of a VVER version of SCORPIO has been done in co-operation with the Nuclear Research Institute Rez, and industry partners in the Czech Republic. The first system is installed at Dukovany NPP, where the Site Acceptance Test was completed 6. March 1998.(author)

Fusion of eastern and western technology in VVER 1000 NPP upgrade

International Nuclear Information System (INIS)

Ubra, O.; Fleischhans, J.; Kveton, M.

1997-01-01

An extensive modernization program upgrading two units of VVER 1000 type of the Czech nuclear power plant (NPP) Temelin to meet the latest international standards is presented. The program is based primarily on combination of eastern and western technology and it has been implemented during plant construction. The NPP Temelin was originally designed according to the standards of the former Soviet Union. After a series of reviews in the 1990s, a decision was made by the Temelin management of upgrade the design of the plant, including the supply of fuel and instrumentation and control system by a western company. The adoption of western technology and practices has helped to solve a large number of IAEA safety issues related to design and operation of VVER 1000 NPP. Details on the current Temelin design and other related safety matters are presented

Study of long-term loss of all AC power supply sources for VVER-1000/V320 in connection with application of new engineering safety features for SAMG

International Nuclear Information System (INIS)

Borisov, Evgeni; Grigorov, Dobrin; Mancheva, Kaliopa

2013-01-01

Highlights: • In this study we presented analysis for a new SAMG approach. • The approach is applicable for all PWR reactors from 2nd generation. • We investigated two scenarios with total black out. • The RELAP/MOD 3.2 computer code is used in performing the analyses. - Abstract: This paper presents the results of analysis for application of a new Severe Accident Management Guideline (SAMG) approach which is specifically applied for VVER-1000/B320 reactor installations. In general, this innovative approach is fully applicable for all the pressurized water reactors from second generation. The purposes of the analysis for the new SAMG approach application are as follows: • To represent suggestions for new engineering safety features application for SAMG strategies. • To assess the applicability of the new engineering safety features and means for SAMG strategies in case of loss of all off-site power supply sources for VVER-1000/B320 reactor installations. • To represent important operator actions and to analyse the effectiveness of these actions for accidents management in compliance with the new approach. • The RELAP5/MOD3.3 computer code has been used in performing the analyses in a VVER-1000 Nuclear Power Plant (NPP) model. The input data deck for the analysis is optimized, verified and validated

East/West cooperation on the safety of USSR-designed nuclear power stations

International Nuclear Information System (INIS)

Spencer, P.H.

1991-01-01

In the aftermath of the accident at the Chernobyl nuclear power station in the Soviet Union, nuclear power plant operators throughout the world came together in May 1989 to form the World Association of Nuclear Operators (WANO). When it became clear that the operators of plants of an early design supplied by the USSR needed assistance in the upgrading of the safety of these units, WANO was uniquely placed to assist and facilitate in this. In July 1990, WANO took the decision to form a special project to assist the operators of the VVER 440/230 plants in their efforts to increase the safety standards for these units. The work performed by this special project team is described

A new optimization method based on cellular automata for VVER-1000 nuclear reactor loading pattern

International Nuclear Information System (INIS)

Fadaei, Amir Hosein; Setayeshi, Saeed

2009-01-01

This paper presents a new and innovative optimization technique, which uses cellular automata for solving multi-objective optimization problems. Due to its ability in simulating the local information while taking neighboring effects into account, the cellular automata technique is a powerful tool for optimization. The fuel-loading pattern in nuclear reactor cores is a major optimization problem. Due to the immensity of the search space in fuel management optimization problems, finding the optimum solution requires a huge amount of calculations in the classical method. The cellular automata models, based on local information, can reduce the computations significantly. In this study, reducing the power peaking factor, while increasing the initial excess reactivity inside the reactor core of VVER-1000, which are two apparently contradictory objectives, are considered as the objective functions. The result is an optimum configuration, which is in agreement with the pattern proposed by the designer. In order to gain confidence in the reliability of this method, the aforementioned problem was also solved using neural network and simulated annealing, and the results and procedures were compared.

Experimental support of the bleed and feed accident management measures for VVER-440/213 type reactors

International Nuclear Information System (INIS)

Szabados, L.

2002-01-01

In the original design of the VVER-440/213 type nuclear power plants event oriented emergency operating procedures (EOP) were implemented. In the last years, however, new symptom based procedures of Westinghouse-type have been developed and partly implemented for the plants in Central Europe including the Paks Nuclear Power Plant. Paper gives a short review of the experiments performed in the PMK-2 facility to study the effectiveness of the bleed and feed strategies and to get experimental data bases for the validation of thermohydraulic system codes like RELAP5, ATHLET and CATHARE.(author)

Economics of Nuclear Power Plant and the development of nuclear power in Viet Nam

International Nuclear Information System (INIS)

Thanh, Thuy Nguyen Thi; Song, JinHo; Ha, Kwang Soon

2015-01-01

There are many factors affecting the capital costs like: increased plant size, multiple unit construction, improved construct methods, increase the lifetime of plant and so on, and beside is technical to enhancing the safety for NPPs. For the question that whether building a NPP is really economic than other energy resources or not, we will find the answer by comparing the USD per kWh of different energy sources as: nuclear power, coal, oil, hydro natural energy sources. The situation of energy in Vietnam was also mentioned in this paper. Vietnam has an abundant natural resources likes: coal, gas, hydro power etc, but from year 2013 to now Vietnam facing of electricity shortage and to solve the problem, Vietnam Government has chosen nuclear power energy to achieve energy balance between the rate of energy consumption and the ability to energy supply. Eight units will be built in Vietnam and in October 2014 Vietnamese officials have chosen Rosatom's AES-2006 design with VVER-1200/v-491 reactors for country's first nuclear power plant at Ninh Thuan and a second plant should follow based on a partnership with Japan. In this paper, the breakdown of NPP costs is considered. All the costs for building a NPP includes: the investment costs are the largest components (about 60%), fuel costs (15%), O and M costs (25%) and external costs are lower than 1% of the kWh costs. The situation for energy in Vietnam was mentioned with increase annually by 5.5 %, and now the shortage electricity is the big problem in power section. The purpose of this report is to give a general picture to consider the cost of nuclear power. It includes all the costs for building a nuclear power plant like total capital investment costs, production costs, external costs in which the capital investment costs is the largest component of the kWh cost. Nuclear energy Power was chosen to deal with situation of diminishing resources shortages

Economics of Nuclear Power Plant and the development of nuclear power in Viet Nam

Energy Technology Data Exchange (ETDEWEB)

Thanh, Thuy Nguyen Thi; Song, JinHo [University of Science and Technology, Daejeon (Korea, Republic of); Ha, Kwang Soon [KAERI, Daejeon (Korea, Republic of)

2015-05-15

There are many factors affecting the capital costs like: increased plant size, multiple unit construction, improved construct methods, increase the lifetime of plant and so on, and beside is technical to enhancing the safety for NPPs. For the question that whether building a NPP is really economic than other energy resources or not, we will find the answer by comparing the USD per kWh of different energy sources as: nuclear power, coal, oil, hydro natural energy sources. The situation of energy in Vietnam was also mentioned in this paper. Vietnam has an abundant natural resources likes: coal, gas, hydro power etc, but from year 2013 to now Vietnam facing of electricity shortage and to solve the problem, Vietnam Government has chosen nuclear power energy to achieve energy balance between the rate of energy consumption and the ability to energy supply. Eight units will be built in Vietnam and in October 2014 Vietnamese officials have chosen Rosatom's AES-2006 design with VVER-1200/v-491 reactors for country's first nuclear power plant at Ninh Thuan and a second plant should follow based on a partnership with Japan. In this paper, the breakdown of NPP costs is considered. All the costs for building a NPP includes: the investment costs are the largest components (about 60%), fuel costs (15%), O and M costs (25%) and external costs are lower than 1% of the kWh costs. The situation for energy in Vietnam was mentioned with increase annually by 5.5 %, and now the shortage electricity is the big problem in power section. The purpose of this report is to give a general picture to consider the cost of nuclear power. It includes all the costs for building a nuclear power plant like total capital investment costs, production costs, external costs in which the capital investment costs is the largest component of the kWh cost. Nuclear energy Power was chosen to deal with situation of diminishing resources shortages.

Comprehensive survey of the Russian nuclear industry

International Nuclear Information System (INIS)

2004-03-01

This document presents the organization of nuclear activities in the Russian federation: Minatom and its replacement by the federal agency of atomic energy, personnel, nuclear power plants (VVER, RBMK, fast neutron and mixed reactors), availability and power production, export of activities (construction of nuclear power plants in Slovakia, Iran, China, India, project in Viet Nam), expansion of the nuclear power plants park (improvement of plants safety, increase of service life), completion of uncompleted plants, the construction of which was stopped after the Chernobyl accident and the reorganization of the former-USSR, construction of new generation power plants (VVER-640, -1000 and -1500), fuel cycle facilities (geographical distribution, production of natural uranium, conversion and enrichment), fuel fabrication, reprocessing processes and spent fuel storage, management of radioactive wastes (leasing), R and D activities (organizations and institutes), research programs of the international scientific and technical center, nuclear safety authority (Gosatomnadzor - GAN). (J.S.)

Ukrainian Nuclear Society International Conference 'Modernization of the NPP with VVER reactor' (abstracts)

International Nuclear Information System (INIS)

Bar'yakhtar, V.G.

1999-01-01

Abstracts of the papers presented at International conference of the Ukrainian Nuclear Society 'Modernization of the NPP with VVER reactor'. The following problems are considered: improving the NPP's safety and reliability; reactor modernization, the lifetime prolongation; increasing of the reactor operating characteristics; methods of capacity factor increasing: refueling control, maintenance control; technical and economical aspects of NPP modernization; modernization of the automated control system of the fuel process at the NPP's; technical features and methods for the continued radiation and technology control at the NPP's; training, increasing the staff qualification and NPP modernization

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

Improving nuclear safety of VVER-440 units

International Nuclear Information System (INIS)

Nochev, T.; Sabinov, S.

2001-01-01

In this paper authors deals with improvement of nuclear safety of WWER-440 units in Kozloduy NPP. Main directions for improving nuclear safety of WWER-440 units were: - to expand number of the design accident; - to increase reliability of equipment important for the safety; - to decrease the probability of initiating events; - improvements the integrity of the primary circuit (application LBB concept, qualification of the pressure safety valves to avoid pressurized thermal shock); - improvement of the fire protection; - improvement of the operation including upgrading and improvement of operational documents, implementation of new system for training the operators and etc.; - reassessment of the seismic response of the plant. Main actions were made at NPP Kozloduy to increase nuclear safety of VVER-440 units. 1. Modernization of Emergency High Pressure Safety Injection System. The modernization includes dividing of independent channels with reservation of active elements. Pumps were exchanged with more effective and reliable ones. HPSIS was increased reliability in general through decrease number of active elements and exchanged with passive. 2. For the purpose of avoiding fast cooling at the primary circuit and obtaining thermal shock of reactor vessel, Main Safety Insulation Valves are installed at NPP Kozloduy. 3. Modernization of Emergency power supplies AC. Oil breakers VMP-10 are exchanged with gas FS-4. 4. Generator breakers are installed to decrease probability of loss power supply and blackout. They provide reliable power supply to the system important for the safety in case of failure on generator. 5. I and C system has been qualified and optimized. 6. Reassessments of Limiting Conditions of Operation and new scram signals have been introduced. 7. An operators-oriented Informational System has been developed. It includes ensuring and updating of equipment data, new informational support of operator and etc. 8. A new auxiliary independent system for

Safety improvements made at the Loviisa nuclear power plant to reduce fire risks originating from the turbine generators

International Nuclear Information System (INIS)

Virolainen, T.; Marttila, J.; Aulamo, H.

1998-01-01

Comprehensive upgrading measures have been completed for the Loviisa Nuclear Power Plant (modified VVER440/V213). These were carried out from the start of the design phase and during operation to ensure safe plant shutdown in the event of a large turbine generator oil fire. These modifications were made mainly on a deterministic basis according to specific risk studies and fire analyses. As part of the probabilistic safety assessment, a fire risk analysis was made that confirmed the importance of these upgrading measures. In fact, they should be considered as design basis modifications for all VVER440 plants. (author)

Nuclear power development status in Russia and China

International Nuclear Information System (INIS)

Hara, Taito

2016-01-01

Russia and China have clear policy for the export of nuclear reactors, and both countries conduct negotiations with the initiative of the government. In Russia, Atomenergoprom, which controls civilian nuclear power sector, is in charge, and in China, CNNC, CGN, and SPI are in charge. As for the development of new type reactors, Russian type VVER-1200 is led by NIAEP and Atomproekt, and China type CAP 1400 and Hualong-1 are led by CNNC, CGN, and SPI. The next reactor export is considered to be an improved type of the third generation. Furthermore, both countries are proceeding with the construction and planning of a variety of the fourth generation reactors. As for the power generation and construction costs of domestic nuclear reactors in each country, three countries such as South Korea, China, and Russia hold a dominant position, keeping the costs significantly lower than those in Japan, the United States, and France. In Russia and China, the governments approve government support loans of approximately 5 to 9 billion dollars per reactor for exporting reactors. For developing countries, where financial resources are limited, this system is considered to be a powerful incentive for importing nuclear reactors in combination with BOO contract system that covers from construction to operation. Japan's nuclear reactor exports are planned for the UK, Vietnam, and Turkey. In addition, a nuclear power agreement with India has been agreed in principle, and the order receipt of Japanese power plant manufacturers is expected. (A.O.)

Validation of coupled neutronic / thermal-hydraulic codes for VVER reactors. Final report

Energy Technology Data Exchange (ETDEWEB)

Mittag, S.; Grundmann, U.; Kliem, S.; Kozmenkov, Y.; Rindelhardt, U.; Rohde, U.; Weiss, F.-P.; Langenbuch, S.; Krzykacz-Hausmann, B.; Schmidt, K.-D.; Vanttola, T.; Haemaelaeinen, A.; Kaloinen, E.; Kereszturi, A.; Hegyi, G.; Panka, I.; Hadek, J.; Strmensky, C.; Darilek, P.; Petkov, P.; Stefanova, S.; Kuchin, A.; Khalimonchuk, V.; Hlbocky, P.; Sico, D.; Danilin, S.; Ionov, V.; Nikonov, S.; Powney, D.

2004-08-01

In recent years, the simulation methods for the safety analysis of nuclear power plants have been continuously improved to perform realistic calculations. Therefore in VALCO work package 2 (WP 2), the usual application of coupled neutron-kinetic / thermal-hydraulic codes to VVER has been supplemented by systematic uncertainty and sensitivity analyses. A comprehensive uncertainty analysis has been carried out. The GRS uncertainty and sensitivity method based on the statistical code package SUSA was applied to the two transients studied earlier in SRR-1/95: A load drop of one turbo-generator in Loviisa-1 (VVER-440), and a switch-off of one feed water pump in Balakovo-4 (VVER-1000). The main steps of these analyses and the results obtained by applying different coupled code systems (SMABRE - HEXTRAN, ATHLET - DYN3D, ATHLET - KIKO3D, ATHLET - BIPR-8) are described in this report. The application of this method is only based on variations of input parameter values. No internal code adjustments are needed. An essential result of the analysis using the GRS SUSA methodology is the identification of the input parameters, such as the secondary-circuit pressure, the control-assembly position (as a function of time), and the control-assembly efficiency, that most sensitively affect safety-relevant output parameters, like reactor power, coolant heat-up, and primary pressure. Uncertainty bands for these output parameters have been derived. The variation of potentially uncertain input parameter values as a consequence of uncertain knowledge can activate system actions causing quite different transient evolutions. This gives indications about possible plant conditions that might be reached from the initiating event assuming only small disturbances. In this way, the uncertainty and sensitivity analysis reveals the spectrum of possible transient evolutions. Deviations of SRR-1/95 coupled code calculations from measurements also led to the objective to separate neutron kinetics from

VVER-specific features regarding core degradation - Status Report

International Nuclear Information System (INIS)

Hozer, Z.; Trambauer, K.; Duspiva, J.

1999-01-01

The objective of this report is to compare VVER reactors to pressurised water reactors (PWRs) of Western design from the point of view of core degradation phenomena using the terminology which was applied to the systematisation of severe accident phenomena in earlier CSNI reports. In the following the acronym 'PWR' is used for a PWR of Western design. The basic design features are described and the most important parameters are summarised in order to identify the differences between the two reactor types. In some specific cases the comparison shows more similarities with boiling water reactors (BWRs) than with PWRs. The known VVER experimental support is also summarised. RBMKs are not included in this report, as this reactor type is not operated in OECD countries, furthermore its design is completely different from those of VVERs and PWRs. The scope of this report is limited to in-vessel severe fuel damage phenomena. Neither thermal hydraulic processes involving no core degradation, nor containment phenomena, are discussed in detail. The VVER (water-cooled water-moderated power reactor) is a pressurised light water reactor of Soviet design. It operates on the same principles as a Western PWR reactor and uses similar technological systems. The primary coolant is pressurised water, which heats up in the reactor core and steam is produced on the secondary side of steam generators. The comparison of basic geometrical and technological parameters pointed out some differences between a PWR and a VVER, but it should be noted that differences exist even between two Western PWRs of different design. The VVER reactors are special types of PWRs, the most important design features of which are the horizontal steam generators and the hexagonal core structure. Similarity between PWR and VVER reactors was found in the comparison of dominant accidents sequences leading to core melt. The accident progression sequence consists of the same steps for VVERs and PWRs. The larger water

Analysing The Thermalhydraulic Parameters Of VVER-1000 Reactor For The Accident Of Steam Generator Tube Rupture

International Nuclear Information System (INIS)

Luu Nam Hai; Truong Cong Thang

2011-01-01

To ensure the safety operation of nuclear power plant (NPP), a lot of postulated accident scenarios were considered and analysed. This research chose and analysed the accident of steam generator tube rupture (SGTR) under the actual plant conditions by using the simulation program PCTRAN. The SGTR accident is happen when the NPP is under operation with the steady state condition (power of 3000 MWth, primary pressure of 157 bar and secondary pressure of 63 bar). The accident is initiated by creating a break with equivalent diameter of 100 mm in the area of lower row heat exchanging tubes. The result of analysis is compared with the calculation of the Shariz University, Iran using the thermal hydraulics code RELAP5/mod3.2 and the report in the PSAR data of VVER-1000. This comparison shows that it is possible for using PCTRAN to analyse accidents of VVER-1000 reactor. (author)

Qualification of coupled 3D neutron kinetic/thermal hydraulic code systems by the calculation of a VVER-440 benchmark. Re-connection of an isolated loop

Energy Technology Data Exchange (ETDEWEB)

Kotsarev, Alexander; Lizorkin, Mikhail [National Research Centre ' Kurchatov Institute' , Moscow (Russian Federation); Bencik, Marek; Hadek, Jan [UJV Rez, a.s., Rez (Czech Republic); Kozmenkov, Yaroslav; Kliem, Soeren [Helmholtz-Zentrum Dresden-Rossendorf (HZDR) e.V., Dresden (Germany)

2016-09-15

The 7th AER dynamic benchmark is a continuation of the efforts to validate the codes systematically for the estimation of the transient behavior of VVER type nuclear power plants. The main part of the benchmark is the simulation of the re-connection of an isolated circulation loop with low temperature in a VVER-440 plant. This benchmark was calculated by the National Research Centre ''Kurchatov Institute'' (with the code ATHLET/BIPR-VVER), UJV Rez (with the code RELAP5-3D {sup copyright}) and HZDR (with the code DYN3D/ATHLET). The paper gives an overview of the behavior of the main thermal hydraulic and neutron kinetic parameters in the provided solutions.

High energy pipe line break postulations and their mitigation - examples for VVER nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Zdarek, J.; Pecinka, L.; Kadecka, P.; Dotrel, J. [Nuclear Res. Inst., Rez (Czech Republic)

1998-11-01

The concept and the proposals for the protection and reinforcement of equipment against the effects of postulated rupture of the high-energy piping, in VVER Plant, are presented. The most recent version of the US NRC Guidelines has been used. The development of the legislation, the basic approach and selection of criteria for the assessment of the rupture of high energy piping, provide the basis for the application of the separation concept in the overall safety philosophy. (orig.)

High energy pipe line break postulations and their mitigation - examples for VVER nuclear power plants

International Nuclear Information System (INIS)

Zdarek, J.; Pecinka, L.; Kadecka, P.; Dotrel, J.

1998-01-01

The concept and the proposals for the protection and reinforcement of equipment against the effects of postulated rupture of the high-energy piping, in VVER Plant, are presented. The most recent version of the US NRC Guidelines has been used. The development of the legislation, the basic approach and selection of criteria for the assessment of the rupture of high energy piping, provide the basis for the application of the separation concept in the overall safety philosophy. (orig.)

Decay heat power of spent nuclear fuel of power reactors with high burnup at long-term storage

Directory of Open Access Journals (Sweden)

Ternovykh Mikhail

2017-01-01

Full Text Available Decay heat power of actinides and fission products from spent nuclear fuel of power VVER-1000 type reactors at long-term storage is calculated. Two modes of storage are considered: mode in which single portion of actinides or fission products is loaded in storage facility, and mode in which actinides or fission products from spent fuel of one VVER reactor are added every year in storage facility during 30 years and then accumulated nuclides are stored without addition new nuclides. Two values of fuel burnup 40 and 70 MW·d/kg are considered for the mode of storage of single fuel unloading. For the mode of accumulation of spent fuel with subsequent storage, one value of burnup of 70 MW·d/kg is considered. Very long time of storage 105 years accepted in calculations allows to simulate final geological disposal of radioactive wastes. Heat power of fission products decreases quickly after 50-100 years of storage. The power of actinides decreases very slow. In passing from 40 to 70 MW·d/kg, power of actinides increases due to accumulation of higher fraction of 244Cm. These data are important in the back end of fuel cycle when improved cooling system of the storage facility will be required along with stronger radiation protection during storage, transportation and processing.

Decay heat power of spent nuclear fuel of power reactors with high burnup at long-term storage

Science.gov (United States)

Ternovykh, Mikhail; Tikhomirov, Georgy; Saldikov, Ivan; Gerasimov, Alexander

2017-09-01

Decay heat power of actinides and fission products from spent nuclear fuel of power VVER-1000 type reactors at long-term storage is calculated. Two modes of storage are considered: mode in which single portion of actinides or fission products is loaded in storage facility, and mode in which actinides or fission products from spent fuel of one VVER reactor are added every year in storage facility during 30 years and then accumulated nuclides are stored without addition new nuclides. Two values of fuel burnup 40 and 70 MW·d/kg are considered for the mode of storage of single fuel unloading. For the mode of accumulation of spent fuel with subsequent storage, one value of burnup of 70 MW·d/kg is considered. Very long time of storage 105 years accepted in calculations allows to simulate final geological disposal of radioactive wastes. Heat power of fission products decreases quickly after 50-100 years of storage. The power of actinides decreases very slow. In passing from 40 to 70 MW·d/kg, power of actinides increases due to accumulation of higher fraction of 244Cm. These data are important in the back end of fuel cycle when improved cooling system of the storage facility will be required along with stronger radiation protection during storage, transportation and processing.

Backfitting of Nuclear Power Plant Bohunice V1 in Slovakia

International Nuclear Information System (INIS)

Ferenc, M.

1999-01-01

Nuclear power plants in the Slovak Republic generate almost 55 % of electricity. The operating organization and the Nuclear Regulatory Authority of the Slovak Republic pay a great attention to safe and reliable operation of four units with VVER 440 reactors at Bohunices site and one in Mochovce side. Engineering and design organizations in cooperation with well known international companies prepare evaluation of safety conditions, safety analyses and projects for the implementation of modifications to upgrade the nuclear safety of the units in operation. A gradual safety upgrading (reconstruction) of the V-1 Bohunice plant has been in progress, a modernization of the V-2 Bohunice plant is being prepared. Simultaneously the commissioning of Unit 2 at the Mochovce plant is being implemented.(author)

A 25% double-ended LOCA in the PSB-VVER facility

International Nuclear Information System (INIS)

Blinkov, V.N.; Lipatov, I.A.; Dremin, G.I.

2003-01-01

The paper presents the results of the experimental investigation in the PSB-VVER facility and post-test analysis with RELAP5/MOD3.3 of the thermal-hydraulic response of the PSB-VVER to a 25% double-ended Hot Leg Break (HLB). The test scenario included loss of off-site power concurrently with the scram-signal and the safety system operation as described in the reference VVER-1000 operational manual in the case of this type of accident assuming one diesel-generator failure. The key transient parameter trends as well as sequence of events and phenomena are given in the paper. RELAP5/MOD3.3 a post-test analysis has been performed using the experimental data gained as a base. The reasonable qualitative agreement between the key calculated and measured variables has been shown. The quantitative code accuracy evaluation has shown that the total average amplitude of the main parameters' deviations AA tot tot < 0.28 that corresponds to satisfactory quality of the VVER-1000 hot leg guillotine break LOCA modeling in the PSB-VVER. (author)

Management of primary-to-secondary leaks at Loviisa nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Mohnsen, B.; Jaenkaelae, K. [IVO International Ltd, Vantaa (Finland)

1995-12-31

The Loviisa Nuclear power plant consisting of two VVER-440 type press water reactor units has been in commercial operation since the late 1970`s. Specific features for VVER-440 reactors are six primary loops with horizontal steam generators and main gate valves. The structure of the horizontal steam generators construction may cause a large primary to secondary leak in case of a break in the cover of the primary collector. An accident where two primary collector covers opened totally and two covers opened partly took place in Rovno, Ukraine January 1982. Primary to secondary leaks are one of the main contributors to the core melt frequency in VVER reactors according to the Loviisa 1 Probabilistic Safety Assessment. The high core damage contribution has set requirements for the development of effective means to cope with all sizes of primary to secondary leaks in the steam generator. A concept for all leak sizes has been developed for Loviisa 1 and 2. The solution includes four main areas which are a new steam generator leakage monitoring system based on nitrogen-16 measurement, an upgraded pressurizer spray system, an increased emergency cooling water reserve and an automated isolation of the defected steam generator.

Management of primary-to-secondary leaks at Loviisa nuclear power plant

International Nuclear Information System (INIS)

Mohnsen, B.; Jaenkaelae, K.

1995-01-01

The Loviisa Nuclear power plant consisting of two VVER-440 type press water reactor units has been in commercial operation since the late 1970's. Specific features for VVER-440 reactors are six primary loops with horizontal steam generators and main gate valves. The structure of the horizontal steam generators construction may cause a large primary to secondary leak in case of a break in the cover of the primary collector. An accident where two primary collector covers opened totally and two covers opened partly took place in Rovno, Ukraine January 1982. Primary to secondary leaks are one of the main contributors to the core melt frequency in VVER reactors according to the Loviisa 1 Probabilistic Safety Assessment. The high core damage contribution has set requirements for the development of effective means to cope with all sizes of primary to secondary leaks in the steam generator. A concept for all leak sizes has been developed for Loviisa 1 and 2. The solution includes four main areas which are a new steam generator leakage monitoring system based on nitrogen-16 measurement, an upgraded pressurizer spray system, an increased emergency cooling water reserve and an automated isolation of the defected steam generator

Management of primary-to-secondary leaks at Loviisa nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Mohnsen, B; Jaenkaelae, K [IVO International Ltd, Vantaa (Finland)

1996-12-31

The Loviisa Nuclear power plant consisting of two VVER-440 type press water reactor units has been in commercial operation since the late 1970`s. Specific features for VVER-440 reactors are six primary loops with horizontal steam generators and main gate valves. The structure of the horizontal steam generators construction may cause a large primary to secondary leak in case of a break in the cover of the primary collector. An accident where two primary collector covers opened totally and two covers opened partly took place in Rovno, Ukraine January 1982. Primary to secondary leaks are one of the main contributors to the core melt frequency in VVER reactors according to the Loviisa 1 Probabilistic Safety Assessment. The high core damage contribution has set requirements for the development of effective means to cope with all sizes of primary to secondary leaks in the steam generator. A concept for all leak sizes has been developed for Loviisa 1 and 2. The solution includes four main areas which are a new steam generator leakage monitoring system based on nitrogen-16 measurement, an upgraded pressurizer spray system, an increased emergency cooling water reserve and an automated isolation of the defected steam generator.

Ecological radiation protection criteria for nuclear power

International Nuclear Information System (INIS)

Kryshev, I.I.

1993-01-01

By now a large quantity of radioactive hazards of all sizes and shapes has accumulated in Russia. They include RBMK, VVER, and BN (fast-neutron) nuclear power plants, nuclear fuel processing plants, radioactive waste dumps, ships with nuclear power units, etc. In order to evaluate the radioecological situation correctly, the characteristics of the radioactive contamination must be compiled in these areas with some system of criteria which will provide an acceptable level of ecological safety. Currently health criteria for radiation protection are, which are oriented to man's radiation protection, predominate. Here the concept of a thresholdless linear dose-response dependence, which has been confirmed experimentally only at rather high doses (above 1 Gy), is taken as the theoretical basis for evaluating and normalizing radiation effects. According to one opinion, protecting people against radiation is sufficient to protect other types of organisms, although they are not necessarily of the same species. However, from the viewpoint of ecology, this approach is incorrect, because it does not consider radiation dose differences between man and other living organisms. The article discusses dose-response dependences for various organisms, biological effects of ionizing radiation, and appropriate radiation protection criteria

Analysis of transients for NPP with VVER-440 using the code SiTAP

International Nuclear Information System (INIS)

Kalinenko, V.

1994-06-01

The report contains analysis of transients ''Loop connection'' and ''Steam generator tube rupture'' for nuclear power plants (NPP) with VVER-440. To obtain more detailed information about NPP's dynamic characteristics, various variants of initial and boundary conditions are considerd. Calculation of these transients was performed using the SiTAP code developed at the Nuclear Safety Institute of the Russian Research Centre ''Kurchatov Institute''. SiTAP code is a multifunctional computer tool for fast analysis of transient and accidental processes of VVER type reactors for engineers working in the field of NPP dynamics. SiTAP can be used form comparative analysis of several variants of accident scenarios to find out the conditions leading to most serious consequences from a safety point of view. In such cases, additional analyses using best-estimate codes should be carried out. The results of SiTAP for a faulty loop connection leading to a boron dilution accident are intended to be used as boundary conditions for a more detailed anlaysis with the aid of the three-dimensional reactor core model DYN3D, developed in the Research Centre Rossendorf for the simulation of reactivity initiated accidents. (orig.)

Rolls-Royce successful modernization of safety-critical Instrumentation and Control (I and C) equipment at the Dukovany VVER 440/213 Nuclear Power Plant, based on SPINLINE 3 platform

International Nuclear Information System (INIS)

Rebreyend, P.; Burel, J.P.; Spoc, J.; Karasek, A.

2010-01-01

Rolls-Royce has provided on-time delivery of a substantial safety-critical I and C overhaul for four Nuclear reactors operated by Czech Republic utility, CEZ a.s. This nine-year project is considered to be one of the largest I and C modernization projects in the world. The Dukovany VVER 440 I and C modernization project and its key success factors are profiled in this paper. The project is in the final stages with the last unit to be completed in 2009. Beginning in September 2000, the project is in compliance with the initial schedule. Rolls-Royce has been designing and manufacturing I and C solutions dedicated to the implementation of safety and safety-related functions in nuclear power plants (NPPs) for more than 30 years. Though the early solutions were non-software-based, since 1984 software-based solutions for safety I and C functions have been deployed in operating NPPs across France and 15 other countries. The Rolls-Royce platform is suitable for implementation of safety I and C functions in new NPPs, as well as in the modernization of safety equipment in existing plants. CEZ a.s. is a major electricity supplier for the national grid. At Dukovany, CEZ a.s. operates four units of VVER-440/213-type reactors producing one quarter of CEZ a.s. electricity production. The first of these units was connected to the grid in 1985. Since the year 2000, the nine-year modernization program has been underway at Dukovany, at a cost of more than 200 million Euros. The equipment replacement was implemented during regular, planned outages of the original equipment and systems. After an international bidding phase, CEZ a.s. awarded a contract to Skoda JS for general engineering and project management. Individual subcontracts were then signed between Skoda JS and a consortium between Rolls-Royce and Areva for modernization of the safety systems, including the Reactor Protection System (RPS), the Reactor Control System (RCS), and the Post-Accident Monitoring System (PAMS). Two

Comprehensive survey of the Russian nuclear industry; Le panorama nucleaire russe

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-03-01

This document presents the organization of nuclear activities in the Russian federation: Minatom and its replacement by the federal agency of atomic energy, personnel, nuclear power plants (VVER, RBMK, fast neutron and mixed reactors), availability and power production, export of activities (construction of nuclear power plants in Slovakia, Iran, China, India, project in Viet Nam), expansion of the nuclear power plants park (improvement of plants safety, increase of service life), completion of uncompleted plants, the construction of which was stopped after the Chernobyl accident and the reorganization of the former-USSR, construction of new generation power plants (VVER-640, -1000 and -1500), fuel cycle facilities (geographical distribution, production of natural uranium, conversion and enrichment), fuel fabrication, reprocessing processes and spent fuel storage, management of radioactive wastes (leasing), R and D activities (organizations and institutes), research programs of the international scientific and technical center, nuclear safety authority (Gosatomnadzor - GAN). (J.S.)

Feasibility and usefulness of reconstructing obsolete power blocks of VVER-440 reactors

International Nuclear Information System (INIS)

Kirichenko, A.M.; Krushenik, S.D.; Sigal, M.V.; Kustov, V.P.

1993-01-01

At the present time, in Russia and in the East European countries there are atomic power stations with first-generation VVER-440 reactors built according to specification which no longer satisfy the more rigorous modern safety standards. Among these power stations are, in particular, the Novovoronezh and the Armenian Atomic Power Station and two blocks of the Kola Atomic Power Station. The search for technical solutions for modernizing these power blocks is complicated because two conditions which are hard to reconcile must be fulfilled: an acceptable safety level must be obtained and the rebuilding must be economically justifiable (particularly since the time of operation of a power block until its standard service life is over is short). Research work undertaken in the All-Union Scientific Research Institute of Atomic Power Stations has shown that one way of overcoming these difficulties may involve changing the operating conditions of the reactor assembly to a less demanding mode of operation. This solution implies an economically justified minimum of structural improvements, provides the required safety level, and prolongs the service life of the power block. The reduction of the thermal power, and consequently, the necessary transfer of a power block to another option

CORONA ACADEMY, Opportunities for Enhancement of Training Capabilities in VVER Technology

International Nuclear Information System (INIS)

Ilieva, M.; Dieguez Porras, P.; Klepakova, A.

2016-01-01

Full text: The general objective of the project CORONA II is to enhance the safety of nuclear installations through further improvement of the training capabilities for providing the necessary personnel competencies in VVER area. More specific objective of the project is to continue the development of a state-of-the-art regional training network for VVER competence called CORONA Academia. The project aims at continuation of the European cooperation and support in this area for preservation and further development of expertise in the nuclear field by improvement of higher education and training. The consortium is focusing its effort on using the most advanced ways of providing training to the trainees, saving cost and time–distance learning and e-learning approaches which will be tested in CORONA II Project. The knowledge management portal will integrate the information on VVER web into a single communication system and develop and implement a semantic web structure to achieve mutual recognition of authentication information with other databases. That will enable the partners to share the materials available in each specific training center. (author

Assessment of Automated Data Analysis Application on VVER Steam Generator Tubing

International Nuclear Information System (INIS)

Picek, E.; Barilar, D.

2006-01-01

INETEC - Institute for Nuclear Technology has developed software package named EddyOne having an option of automated analysis of bobbin coil eddy current data. During its development and site use some features were noticed preventing the wide use automatic analysis on VVER SG data. This article discuss these specific problems as well evaluates possible solutions. With regards to current state of automated analysis technology an overview of advantaged and disadvantages of automated analysis on VVER SG is summarized as well.(author)

Main results of post-irradiation examinations of new-generation fuel assemblies VVER-1000

International Nuclear Information System (INIS)

Zvir, E.; Markov, D.; Polenok, V.; Zhitelev, V.; Kobylyansky, G.

2009-01-01

To increase the competitiveness of Russian nuclear fuel at the foreign market and to improve its technical and economic performance in order to provide a necessary level of safety, it is necessary to solve certain important tasks: Increase of fuel burn-up; Extension of operational lifetime of fuel assemblies and operational reliability of nuclear fuel; Introduction of cost-beneficial and flexible fuel cycles. Alternative fuel assemblies TVSA VVER-1000 and TVS-2 are used as a basis to optimize the nuclear fuel and develop advanced fuel cycles for nuclear power plants with VVER-1000 reactor types. Four fuel assemblies TVSA operated during 1 and up to 6 reactor cycles, reference fuel assembly TVS-2 operated during three reactor cycles and achieved an average fuel burnup of 48MW·day/kgU as well as failed fuel assembly TVS-2 operated during one cycle were examined at RIAR in recent years. The main objectives of these examinations were to obtain experimental data in support of operational integrity of products or to find out reasons of their failure. The performed post-irradiation examinations confirmed the operational integrity of alternative fuel assemblies TVSA including their geometrical stability up to the average fuel burnup of 55 MW·day/kgU over the fuel assembly (FA) (up to the maximal fuel burnup of ∼73 MW·day/kgU in fuel rods) and of TVS-2 up to the average fuel burnup of 48 MW·day/kgU over the fuel assembly. The changes introduced in the design of VVER-1000 fuel assembly during the development of alternative fuel assembly TVSA and TVS-2 did not make any negative effect on fuel rods. It was proved that causes of fuel rod failure were not related to design features of fuel assemblies. The design features and operating conditions of fuel assemblies under examinations are briefly described. Post-irradiation examinations proved the geometrical stability of fuel assemblies TVSA and TVS-2 under operation up to the fuel burnup of ∼50 MW day/kgU, as for the

Core designs of modern VVER projects

International Nuclear Information System (INIS)

Vasilchenko, I.; Kushmanov, S.; Vjalitsyn, V.; Vasilchenko, R.

2015-01-01

The presented operational experience of TVS - 2M (pilot-commercial operation started in 2006 at Balakovo NPP -1) enables to use it as reference for new projects because of similarity in designs and operational conditions. In the paper main parameters of fuel cycles, stability to impact of damaging factors, pilot operation of MG, new alloys, ADF and NTMC, upgrade of FA - 2M for the further power uprating, profiling of Gd-fuel rods for 18-month Fuel Cycle (FC) and perfection of absorber element design are the discussed issues. At the end author concluded that: 1) Core designs of new projects AES-2006 and VVER-TOI are based on extensive successful operational experience of the close prototype of TVS - 2M. 2) All improvements both of technical and economic parameters of fuel are subjected to representative examination by pilot operation at the power units with VVER-1000 being close prototypes of new designs

Optimization of fuel core loading pattern design in a VVER nuclear power reactors using Particle Swarm Optimization (PSO)

International Nuclear Information System (INIS)

Babazadeh, Davood; Boroushaki, Mehrdad; Lucas, Caro

2009-01-01

The two main goals in core fuel loading pattern design optimization are maximizing the core effective multiplication factor (K eff ) in order to extract the maximum energy, and keeping the local power peaking factor (P q ) lower than a predetermined value to maintain fuel integrity. In this research, a new strategy based on Particle Swarm Optimization (PSO) algorithm has been developed to optimize the fuel core loading pattern in a typical VVER. The PSO algorithm presents a simple social model by inspiration from bird collective behavior in finding food. A modified version of PSO algorithm for discrete variables has been developed and implemented successfully for the multi-objective optimization of fuel loading pattern design with constraints of keeping P q lower than a predetermined value and maximizing K eff . This strategy has been accomplished using WIMSD and CITATION calculation codes. Simulation results show that this algorithm can help in the acquisition of a new pattern without contravention of the constraints.

Problems and prospects of nuclear power plants construction

Directory of Open Access Journals (Sweden)

Pergamenshhik Boris Klimentyevich

2014-02-01

Full Text Available 60 years ago, in July 1954 in the city of Obninsk near Moscow the world's first nuclear power plant was commissioned with a capacity of 5 MW. Today more than 430 nuclear units with a total capacity of almost 375000 MW are in operation in dozens of the countries worldwide. 72 electrical power units are currently under construction, 8 of them are located in the Russian Federation. There will be no alternative to nuclear energy in the coming decades. Among the factors contributing to the construction of nuclear power plants reckon limited fossil fuel supply, lack of air and primarily carbon dioxide emissions. The holding back factors are breakdown, hazard, radioactive wastes, high construction costs and long construction period. Nuclear accidents in the power plant of «Three-Mile-Island» in the USA, in Chernobyl and in Japan have resulted in termination of construction projects and closure of several nuclear power plants in the Western Europe. The safety systems have become more complex, material consumption and construction costs have significantly increased. The success of modern competing projects like EPR-1600, AP1000, ABWR, national ones AES-2006 and VVER-TOI, as well as several others, depends not only on structural and configuration but also on construction and technological solutions. The increase of the construction term by one year leads to growth of estimated total costs by 3—10 %. The main improvement potentials include external plate reinforcement, pre-fabricated large-block assembly, production and installation of the equipment packages and other. One of the crucial success factors is highly skilled civil engineers training.

Multiple recycle of REMIX fuel at VVER-1000 operation in closed fuel cycle

Energy Technology Data Exchange (ETDEWEB)

Alekseev, P. N.; Bobrov, E. A., E-mail: evgeniybobrov89@rambler.ru; Chibinyaev, A. V.; Teplov, P. S.; Dudnikov, A. A. [National Research Center Kurchatov Institute (Russian Federation)

2015-12-15

The basic features of loading the VVER-1000 core with a new variant of REMIX fuel (REgenerated MIXture of U–Pu oxides) are considered during its multiple recycle in a closed nuclear fuel cycle. The fuel composition is produced on the basis of the uranium–plutonium regenerate extracted at processing the spent nuclear fuel (SNF) from a VVER-1000, depleted uranium, and the fissionable material: {sup 235}U as a part of highly enriched uranium (HEU) from warheads superfluous for defense purposes or {sup 233}U accumulated in thorium blankets of fusion (electronuclear) neutron sources or fast reactors. Production of such a fuel assumes no use of natural uranium in addition. When converting a part of the VVER-1000 reactors to the closed fuel cycle based on the REMIX technology, the consumption of natural uranium decreases considerably, and there is no substantial degradation of the isotopic composition of plutonium or change in the reactor-safety characteristics at the passage from recycle to recycle.

MEASUREMENTS OF THE CONFINEMENT LEAKTIGHTNESS AT THE KOLA NUCLEAR POWER STATION (UNIT 2) IN RUSSIA

International Nuclear Information System (INIS)

GREENE, G.A.; GUPPY, J.G.

1998-01-01

This is the final report on the INSP project entitled, ''Kola Confinement Leaktightness'' conducted by BNL under the authorization of Project Work Plan WBS 1.2.2.1. This project was initiated in February 1993 to assist the Russians to reduce risks associated with the continued operation of older Soviet-designed nuclear power plants, specifically the Kola VVER-440/230 Units 1 and 2, through upgrades in the confinement performance to reduce the uncontrolled leakage rate. The major technical objective of this-project was to improve the leaktightness of the Kola NPP VVER confinement boundaries, through the application of a variety of sealants to penetrations, doors and hatches, seams and surfaces, to the extent that current technology permitted. A related objective was the transfer, through training of Russian staff, of the materials application procedures to the staff of the Kola NPP. This project was part of an overall approach to minimizing uncontrolled releases from the Kola NPP VVER440/230s in the event of a serious accident, and to thereby significantly mitigate the consequences of such an accident. The US provided materials, application technology, and applications equipment for application of sealant materials, surface coatings, potting materials and gaskets, to improve the confinement leaktightness of the Kola VVER-440/23Os. The US provided for training of Russian personnel in the applications technology

MEASUREMENTS OF THE CONFINEMENT LEAKTIGHTNESS AT THE KOLA NUCLEAR POWER STATION (UNIT 2) IN RUSSIA

Energy Technology Data Exchange (ETDEWEB)

GREENE,G.A.; GUPPY,J.G.

1998-08-01

This is the final report on the INSP project entitled, ``Kola Confinement Leaktightness'' conducted by BNL under the authorization of Project Work Plan WBS 1.2.2.1. This project was initiated in February 1993 to assist the Russians to reduce risks associated with the continued operation of older Soviet-designed nuclear power plants, specifically the Kola VVER-440/230 Units 1 and 2, through upgrades in the confinement performance to reduce the uncontrolled leakage rate. The major technical objective of this-project was to improve the leaktightness of the Kola NPP VVER confinement boundaries, through the application of a variety of sealants to penetrations, doors and hatches, seams and surfaces, to the extent that current technology permitted. A related objective was the transfer, through training of Russian staff, of the materials application procedures to the staff of the Kola NPP. This project was part of an overall approach to minimizing uncontrolled releases from the Kola NPP VVER440/230s in the event of a serious accident, and to thereby significantly mitigate the consequences of such an accident. The US provided materials, application technology, and applications equipment for application of sealant materials, surface coatings, potting materials and gaskets, to improve the confinement leaktightness of the Kola VVER-440/23Os. The US provided for training of Russian personnel in the applications technology.

Experimental Investigation of Operation of VVER Steam Generator in Condensation Mode in the Event of the Severe Accident

Energy Technology Data Exchange (ETDEWEB)

Morozov, Andrey [Institute for Physics and Power Engineering by A.I. Leypunsky, 1 Bondarenko sq. Obninsk, 249033 (Russian Federation)

2008-07-01

For new Russian nuclear power plants with VVER-1200 reactor in the event of a beyond design basis accident, provision is made for the use of passive safety systems for necessary core cooling. These safety systems include the passive heat removal system (PHRS). In the case of leakage in the primary circuit this system assures the transition of steam generators (SG) to operation in the mode of condensation of the primary circuit steam. As a result, the condensate from SG arrives at the core providing its additional cooling. To investigate the condensation mode of VVER SG operation, a large scale HA2M-SG test facility was constructed. The rig incorporates: buffer tank, SG model with scale is 1:46, PHRS heat exchanger. Experiments at the test facility have been performed to investigate condensation mode of operation of SG model at the pressure 0.4 MPa, correspond to VVER reactor pressure at the last stage of the beyond design basis accident. The report presents the test procedure and the basic obtained test results. (authors)

Status and prospects of the core surveillance system SCORPIO-VVER in Czech Republic and Slovakia

International Nuclear Information System (INIS)

Molnar, J.; Vocka, R.

2011-01-01

The SCORPIO-VVER core monitoring system has proved since the first installation at Dukovany NPP in 1999 to be a valuable tool for the reactor operators and reactor physicists. It is now installed on four units of Dukovany NPP (Czech Republic) and two units of Bohunice NPP (Slovak Republic) replacing the original Russian VK3 system. By both Czech and Slovak nuclear regulatory bodies it was licensed as a Technical Specification Surveillance tool. Since it's first installation, the development of SCORPIO-VVER system continues along with the changes in WWER reactors operation. The system is being adapted according the utility needs and several notable improvements in physical modules of the system were introduced. The latest most significant changes were done in connection with implementation of a new digital I and C system, loading of the optimized gadolinium bearing Gd2 fuel assemblies, improvements in the area of core design (neutron physics, core thermal hydraulics and fuel thermal mechanics), adaptation of the system to up-rated unit conditions, in design and methodology of the limit and technical specifications checking (implementation of the on-line shutdown margin calculation to the system) and improvements in the predictive part of the system (Strategy Generator). After the currently finished upgrades (Upgrade 2 at EBO Slovakia in 2009, Upgrade 5 at EDU Czech Republic in 2010) the SCORPIO-VVER is still in focus of Central European nuclear power plants with the road map of modification and implementation up to 2015. In April 2011 the Upgrade 3 at EBO Slovakia has been contracted to support the changed reactor technical specification and for support of the new type of fuel planned to load in 2012. During the summer of 2011 the discussions started with EDU NPP in Czech Republic regarding to the future development of the SCORPIO-VVER system up to 2015. Parallel with the support of current installations at NPPs the project of new installations is ongoing. During

Dry spent fuel storage facility at Kozloduy Nuclear Power Plant

International Nuclear Information System (INIS)

Goehring, R.; Stoev, M.; Davis, N.; Thomas, E.

2004-01-01

The Dry Spent Fuel Storage Facility (DSF) is financed by the Kozloduy International Decommissioning Support Fund (KIDSF) which is managed by European Bank for Reconstruction and Development (EBRD). On behalf of the Employer, the Kozloduy Nuclear Power Plant, a Project Management Unit (KPMU) under lead of British Nuclear Group is managing the contract with a Joint Venture Consortium under lead of RWE NUKEM mbH. The scope of the contract includes design, manufacturing and construction, testing and commissioning of the new storage facility for 2800 VVER-440 spent fuel assemblies at the KNPP site (turn-key contract). The storage technology will be cask storage of CONSTOR type, a steel-concrete-steel container. The licensing process complies with the national Bulgarian regulations and international rules. (authors)

YKAe Research programme on nuclear power plant systems behaviour and operational aspects of safety 1990-1994, Final report

International Nuclear Information System (INIS)

Mattila, L.; Vanttola, T.

1995-04-01

The research programme on Nuclear Power Plant Systems Behaviour and Operational Aspects of Safety was carried out between 1990 and 1994. In the field of Safe operational margins of nuclear fuel and reactor core, an up-to-date steady-state fuel performance model was validated for higher burn-ups and well-characterized VVER fuel experiments were carried out. A comprehensive reactor analysis code system was extended and validated for complex 3-D phenomena, such as ATWS and boron dilution transients. Advanced hydraulics methods were added to the dynamics codes. Experiments were carried out with PACTEL, the most comprehensive thermal-hydraulic test facility for VVER-440-type reactors worldwide. For example, a series of natural circulation tests were provided for the first VVER-related international standard problem of the OECD/NEA. Advanced foreign computer codes for severe accidents were evaluated and modified for the needs of Finnish power plants. Specific progress was made in modelling the reflooding of an overheated core and in the structural analysis of a pressure vessel under corium load, as well as in experimental and theoretical studies of aerosol and hydrogen behaviour. Fire modelling was improved by implementing advanced calculation methods and by validating them against our own experiments and international test data. Techniques in living probabilistic safety assessment and risk decision-making were refined in pilot applications for continuous monitoring, follow-up and management of risks of an operating power plant. In the area of human reliability and organizational performance, factors important for the continuous development of the competence of control room operator teams and plant maintenance staff were identified. (237 refs., 75 figs., 13 tabs.)

Qualification of the nuclear reactor core model DYN3D coupled to the thermohydraulic system code ATHLET, applied as an advanced tool for accident analysis of VVER-type reactors. Final report

International Nuclear Information System (INIS)

Grundmann, U.; Kliem, S.; Krepper, E.; Mittag, S; Rohde, U.; Schaefer, F.; Seidel, A.

1998-03-01

The nuclear reactor core model DYN3D with 3D neutron kinetics has been coupled to the thermohydraulic system code ATHLET. In the report, activities on qualification of the coupled code complex ATHLET-DYN3D as a validated tool for the accident analysis of russian VVER type reactors are described. That includes: - Contributions to the validation of the single codes ATHLET and DYN3D by the analysis of experiments on natural circulation behaviour in thermohydraulic test facilities and solution of benchmark tasks on reactivity initiated transients, - the acquisition and evaluation of measurement data on transients in nuclear power plants, the validation of ATHLET-DYN3D by calculating an accident with delayed scram and a pump trip in VVER plants, - the complementary improvement of the code DYN3D by extension of the neutron physical data base, implementation of an improved coolant mixing model, consideration of decay heat release and xenon transients, - the analysis of steam leak scenarios for VVER-440 type reactors with failure of different safety systems, investigation of different model options. The analyses showed, that with realistic coolant mixing modelling in the downcomer and the lower plenum, recriticality of the scramed reactor due to overcooling can be reached. The application of the code complex ATHLET-DYN3D in Czech Republic, Bulgaria and the Ukraine has been started. Future work comprises the verification of ATHLET-DYN3D with a DYN3D version for the square fuel element geometry of western PWR. (orig.) [de

Westinghouse Electric Company experiences in chemistry on-line monitoring in Eastern European nuclear power plants

International Nuclear Information System (INIS)

Balavage, J.

2001-01-01

Westinghouse Electric Company has provided a number of Chemistry On-Line Monitoring (OLM) Systems to Nuclear Power Plants in Eastern Europe. Eleven systems were provided to the Temelin Nuclear Power Plant in the south of the Czech Republic. Four systems were provided to the Russian NPP at Novovoronezh. In addition, a system design was developed for primary side chemistry monitoring for units 5 and 6 of another eastern European VVER. The status of the Temelin OLM systems is discussed including updates to the Temelin designs, and the other Eastern European installations and designs are also described briefly. Some of the problems encountered and lessons learned from these projects are also discussed. (R.P.)

The FARC fuel archive of VVER

International Nuclear Information System (INIS)

Zizin, M.N.; Parfenova, N.A.; Proselkov, V.N.; Shishkov, L.K.

1998-01-01

The principles of organisation are explained and the structure of the FARC fuel archive for VVER reactors is described. The objective of the archive is accumulation of fuel data, data storage and obtaining the fuel using characteristics. The working version of fuel archive on 01.07.98 is realised, in which the data tables for fuel assemblies for 169 VVER-440 cycles and 35 VVER-1000 cycles are stored. There are two different versions of fuel archive - for VVER-440 (FARC) and for VVER-1000 (FARC1000). A structure of some tables and the texts of programs for them differ. The algorithms and codes for checking integrity, reasonableness and reliability of fuel archive data are developed. (author)

Transient thermal-hydraulic/neutronic analysis in a VVER-1000 reactor core

International Nuclear Information System (INIS)

Seyed khalil Mousavian; Mohammad Mohsen Ertejaei; Majid Shahabfar

2005-01-01

Full text of publication follows: Nowadays, coupled thermal-hydraulic and three-dimensional neutronic codes in order to consider different feedback effects is state of the art subject in nuclear engineering researches. In this study, RELAP5/COBRA and WIMS/CITATION codes are implemented to investigate the VVER-1000 reactor core parameters during Large Break Loss of Coolant Accident (LB-LOCA). In a LB-LOCA, the primary side pressure, coolant density and fuel temperature strongly decrease but the cladding temperature experiences a strong peak. For this purpose, the RELAP5 Best Estimate (BE) system code is used to simulate the LB-LOCA analysis in VVER-1000 nuclear thermal-hydraulic loops. Also, the modified COBRA-IIIc software as a sub-channel analysis code is applied for modeling of VVER-1000 reactor core. Moreover, WIMS and CITATION as a cross section and 3-D neutron flux codes are coupled with thermal-hydraulic codes with the aim of consider the spatial effects through the reactor core. For this reason, suitable software is developed to link and speed up the coupled thermalhydraulic and three-dimensional neutronic calculations. This software utilizes of external coupling concept in order to integrate thermal-hydraulic and neutronic calculations. (authors)

Uranium oxide fuel cycle analysis in VVER-1000 with VISTA simulation code

Science.gov (United States)

Mirekhtiary, Seyedeh Fatemeh; Abbasi, Akbar

2018-02-01

The VVER-1000 Nuclear power plant generates about 20-25 tons of spent fuel per year. In this research, the fuel transmutation of Uranium Oxide (UOX) fuel was calculated by using of nuclear fuel cycle simulation system (VISTA) code. In this simulation, we evaluated the back end components fuel cycle. The back end component calculations are Spent Fuel (SF), Actinide Inventory (AI) and Fission Product (FP) radioisotopes. The SF, AI and FP values were obtained 23.792178 ton/y, 22.811139 ton/y, 0.981039 ton/y, respectively. The obtained value of spent fuel, major actinide, and minor actinide and fission products were 23.8 ton/year, 22.795 ton/year, 0.024 ton/year and 0.981 ton/year, respectively.

Information about AER WG a on improvement, extension and validation of parametrized few-group libraries for VVER 440 and VVER 1000

International Nuclear Information System (INIS)

Mikolas, P.

2009-01-01

Joint AER Working Group A on 'Improvement, extension and validation of parameterized few-group libraries for VVER-440 and VVER-1000' and AER Working group B on 'Core design' eighteenth meeting was hosted by Skoda JS a.s. in Plzen (Czech Republic) during the period of 4 to 6 May 2009. There were present altogether 16 participants from 6 member organizations and 13 presentations were read. Objectives of the meeting of WG A are: Issues connected with spectral calculations and few-groups libraries preparation, their accuracy and validation. Presentations were devoted to some aspects of few group libraries preparations and to the benchmark dealing with VVER-440 follower modeling in calculations. Gy. Hegyi gave some new information about NURESIM-NURISP EU project (ZR-6), R. Zajac spoke about the development of data libraries for codes BIPR-7 and PERMAK, P. Darilek compared FA's with Gd during burning process and Yu. Bilodid described further development of plutonium-based burnup history modeling in DYN3D burnup calculations. G. Hordosy presented results of control rod follower induced local power peaking computational benchmark and J. Svarny described Monte Carlo VVER-440 control rod follower benchmark computations. Future activities are also shortly described in the end of the paper. (author)

Sequence of decommissioning of the main equipment in a central type VVER 440 V-230

International Nuclear Information System (INIS)

Andres, E.; Garcia Ruiz, R.

2014-01-01

IBERDROLA Ingenieria y Construccion S.A.U., leader of consortium with Empresarios Agrupados and INDRA, has developed the Basic Engineering for the decommissioning of contaminated systems and building of a VVER 440 V-230 Nuclear Power Plant, establishing the sequence and methodology for the main equipment fragmentation. For that, it has been designed dry and wet cutting zones to be set up in the area where steam generators, main cooling pumps and pressurizer are located; these components will be dismantled previously. (Author)

Nuclear safety at the Paks Plant

International Nuclear Information System (INIS)

Bajsz, Jozsef; Vamos, Gabor

1991-01-01

The Paks Nuclear Power Plant is located on the Danube river 114 km south of Budapest. It consists of four PWR units of the Soviet VVER-440 design. These are of the second generation design VVER 440 (model 213) with safety features as of 1975. It should be emphasized that these are two different generations of VVER 440 units. This is not always clear, not only to the general public, but sometimes even to people working in the nuclear industry. The widespread criticism of the first generation type 230 reactors is often extended to model 213 reactors, as the differences between the two models are often not sufficiently emphasized. In this situation it is very important to provide balanced information about the advantages and disadvantages of this reactor type. This paper attempts to do that. (author)

The corrosion and corrosion mechanical properties evaluation for the LBB concept in VVERs

Energy Technology Data Exchange (ETDEWEB)

Ruscak, M.; Chvatal, P.; Karnik, D.

1997-04-01

One of the conditions required for Leak Before Break application is the verification that the influence of corrosion environment on the material of the component can be neglected. Both the general corrosion and/or the initiation and, growth of corrosion-mechanical cracks must not cause the degradation. The primary piping in the VVER nuclear power plant is made from austenitic steels (VVER 440) and low alloy steels protected with the austenitic cladding (VVER 1000). Inspection of the base metal and heterogeneous weldments from the VVER 440 showed that the crack growth rates are below 10 m/s if a low oxygen level is kept in the primary environment. No intergranular cracking was observed in low and high oxygen water after any type of testing, with constant or periodic loading. In the framework of the LBB assessment of the VVER 1000, the corrosion and corrosion mechanical properties were also evaluated. The corrosion and corrosion mechanical testing was oriented predominantly to three types of tests: stress corrosion cracking tests corrosion fatigue tests evaluation of the resistance against corrosion damage. In this paper, the methods used for these tests are described and the materials are compared from the point of view of response on static and periodic mechanical stress on the low alloyed steel 10GN2WA and weld metal exposed in the primary circuit environment. The slow strain rate tests and static loading of both C-rings and CT specimens were performed in order to assess the stress corrosion cracking characteristics. Cyclic loading of CT specimens was done to evaluate the kinetics of the crack growth under periodical loading. Results are shown to illustrate the approaches used. The data obtained were evaluated also from the point of view of comparison of the influence of different structure on the stress corrosion cracking appearance. The results obtained for the base metal and weld metal of the piping are presented here.

VVER operational safety improvements: lessons learnt from European co-operation and future research needs

International Nuclear Information System (INIS)

Pazdera, F.; Vasa, I.; Zd'arek, J.

2003-01-01

The paper summarises involvement of Nuclear Research Institute Rez (NRI) in the areas which are directly related to Reactor Operational Safety and Plant Life Management, it also gives an idea how results of the research projects can be used to enhance safety of VVER reactors. These issues are for many years subject of a wide international co-operation effort, covered by such programmes as PHARE, OECD/NEA TACIS, 5th Framework Programme. Nuclear Research Institute participated in the majority of these programmes and projects, which allowed us to evaluate benefits (especially for VVER reactors) of the projects already finalised or running, as well as to formulate so-called 'future research needs', which possibly may be pursued within 6th Framework Programme. The paper highlights the main features of some projects our Institute was and is involved in, emphasising the most important results, expectations and future needs. It also very briefly, deals with some general and particular lessons learnt within these projects and their application to VVER reactors, especially as to their safety improvement. The paper also mentions VVER-focused projects and activities, co-ordinated by the OECD, which should enable to extend multilateral contacts already existing between organisations of the EU countries to include organisations from Russia, USA, Japan and possibly some other countries

Construction of the Plant RT-2 as a way for solving the problem of VVER-1000 spent fuel management in Russia

International Nuclear Information System (INIS)

Lazarev, L.N.; Lyubtsev, R.I.; Egorov, N.N.; Lebedev, V.A.; Revenko, Y.A.; Fedosov, Y.G.; Dubrovskii, V.M.

1993-01-01

Nuclear power in the Russian Federation in the future will be based on the VVER-1000 and it's modifications. To manage the spent fuels from this plant, the Plant RT-2 was designed to process the spent fuel. Plant construction was started in 1984 and stopped in 1989 due to economic difficulties. The necessity of the continuation of the plant is discussed

The complex approach to the flow accelerated cracking in Czech nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Ruscak, M; Splichal, K; Kaplan, J [Nuclear Research Institute, Rez (Czech Republic)

1994-12-31

The paper shows the approach of NRI to the problems of flow accelerated cracking of the secondary piping in VVER nuclear power plants. The utilization of the CHECMATE family codes is described in the framework of other activities to support the prediction and evaluation of damage. The code allows the effects of parameters such as temperature, geometry, mass transport conditions, void fraction and material composition to be assessed. The influence of exact measurement of chromium content is discussed. 2 refs., 6 figs., 1 tab.

The complex approach to the flow accelerated cracking in Czech nuclear power plants

International Nuclear Information System (INIS)

Ruscak, M.; Splichal, K.; Kaplan, J.

1994-01-01

The paper shows the approach of NRI to the problems of flow accelerated cracking of the secondary piping in VVER nuclear power plants. The utilization of the CHECMATE family codes is described in the framework of other activities to support the prediction and evaluation of damage. The code allows the effects of parameters such as temperature, geometry, mass transport conditions, void fraction and material composition to be assessed. The influence of exact measurement of chromium content is discussed. 2 refs., 6 figs., 1 tab

Three-dimensional neutron kinetics-thermal-hydraulics VVER 1000 main steam line break analysis by RELAP5-3D code

International Nuclear Information System (INIS)

Frisani, A.; Parisi, C.; D'Auria, F.

2007-01-01

After the development and the assessment of Three-Dimensional (3D) Neutron Kinetics (NK) - 1D Thermal-Hydraulics (TH) coupled codes analyses methods, deterministic nuclear safety technology is nowadays producing noticeable efforts for the validation of 3D NK - 3D TH coupled codes analyses methods too. Thus, the purpose of this work was to address the capability of the RELAP5-3D 3D NK-3D TH code to reproduce VVER 1000 Nuclear Power Plant (NPP) core dynamic in simulating the mixing effects that could happen in the vessel downcomer and lower plenum during some scenarios. The work was developed in three steps. The first step dealt with the 3D TH modeling of the Kozloduy-6 VVER 1000 reactor pressure vessel. Then this model was validated following a Steam Generator Isolation transient. The second step has been the development of a 3D NK nodalization for the reactor core region. Then the 3D NK model was directly coupled with the previously developed 3D TH model. The third step was the calculation of a Main Steam Line Break (MSLB) transient. The 3D NK global nuclear parameters were then compared with the 0-D results showing a good agreement; nevertheless only the 3D NK- 3D TH model allowed the calculation of each single assembly power trend for this strong NK-TH asymmetric transient. (author)

Insights from the U.S. department of Energy plant safety evaluation program of VVER and RBMK reactors

International Nuclear Information System (INIS)

Petri, M.C.; Binder, J.L.; Pasedag, W.F.

2001-01-01

Throughout the years 1990 the U.S. Department of Energy has worked build capability in countries of the former Soviet Union to assess the safety of their VVER and RBMK reactors. Through this Plant Safety Evaluation Program, deterministic and probabilistic analyses have been used to provide a documented plant risk profile to support safe plant operation and to set priorities for safety upgrades. Work has been sponsored at thirteen nuclear power plant sites in eight countries. The Plant Safety Evaluation Program has resulted in immediate and long-term safety benefits for the Soviet-designed nuclear plants. (author)

PSB-VVER simulation of Kozloduy NPP 'loss of feed water transient'

Energy Technology Data Exchange (ETDEWEB)

Groudev, P.P. [Institute for Nuclear Research and Nuclear Energy, Tzarigradsko Shaussee 72, Sofia 1784 (Bulgaria)]. E-mail: pavlinpg@inrne.bas.bg; Stefanova, A.E. [Institute for Nuclear Research and Nuclear Energy, Tzarigradsko Shaussee 72, Sofia 1784 (Bulgaria)]. E-mail: antoanet@inrne.bas.bg; Gencheva, R.V. [Institute for Nuclear Research and Nuclear Energy, Tzarigradsko Shaussee 72, Sofia 1784 (Bulgaria)]. E-mail: roseh@inrne.bas.bg; Pavlova, M.P. [Institute for Nuclear Research and Nuclear Energy, Tzarigradsko Shaussee 72, Sofia 1784 (Bulgaria)]. E-mail: pavlova@inrne.bas.bg

2005-04-01

This paper provides a comparison between the PSB test facility experimental results obtained during the simulation of loss of feed water transient (LOFW) and the calculation results received by INRNE computer model of the same test facility. Integral thermal-hydraulic PSB-VVER test facility located at Electrogorsk Research and Engineering Center on NPPs Safety (EREC) was put in operation in 1998. The structure of the test facility allows experimental studies under steady state, transient and accident conditions. RELAP5/MOD3.2 computer code has been used to simulate the loss of feed water transient in a PSB-VVER model. This model was developed at the Institute for Nuclear Research and Nuclear Energy for simulation of loss of feed water transient. The objective of the experiment 'loss of feed water', which has been performed at PSB-VVER test facility is simulation of Kozloduy NPP LOFW transient. One of the main requirements to the experiment scenario has been to reproduce all main events and phenomena that occurred in Kozloduy NPP during the LOFW transient. Analyzing the PSB-VVER test with a RELAP5/MOD3.2 computer code as a standard problem allows investigating the phenomena included in the VVER code validation matrix as 'integral system effects' and 'natural circulation'. For assessment of the RELAP5 capability to predict the 'Integral system effect' phenomenon the following RELAP5 quantities are compared with external trends: the primary pressure and the hot and cold leg temperatures. In order to assess the RELAP5 capability to predict the 'Natural circulation' phenomenon the hot and cold leg temperatures behavior have been investigated. This report was possible through the participation of leading specialists from Kozloduy NPP and with the support of Argonne National Laboratory (ANL), under the International Nuclear Safety Program (INSP) of the United States Department of Energy.

Compact simulators for WWER-440 type nuclear power plants

International Nuclear Information System (INIS)

Vegh, E.; Janosy, J.S.

1991-09-01

This paper describes a compact simulator for VVER-440 type plants. Up till now three simulators have been delivered: to Paks Nuclear Power Plant (Hungary), and to Kola and Rovno NPPs (Soviet Union). In this compact simulator the modelling complexity of the plant is almost similar to that of a full-scope one apart from the Control Room being replaced by a Control Desk and four colour graphic display units. The simulation of the plant covers the whole operating range: from cold shut-down state to nominal power level. The simulator contains up to 32 different initial conditions. Moreover, every 5 minutes the simulator produces so called 'snapshots', i.e. disc images of the Data Base. Using these snapshots the instructor can go back in time (called backtracking) in order to repeat some previously passed events

VVER fuel. Results of post irradiation examination

International Nuclear Information System (INIS)

Smirnov, V.P.; Markov, D.V.; Smirnov, A.V.; Polenok, V.S.; Perepelkin, S.O.; Ivashchenko, A.A.

2005-01-01

The present paper presents the main results of post-irradiation examination of more than 40 different fuel assemblies (FA) operated in the cores of VVER-1000 and VVER-440-type power reactors in a wide range of fuel burnup. The condition of fuel assembly components from the viewpoint of deformation, corrosion resistance and mechanical properties is described here. A serviceability of the FA design as a whole and interaction between individual FA components under vibration condition and mechanical load received primary emphasis. The reasons of FA damage fuel element failure in a wide range of fuel burnup are also analyzed. A possibility and ways of fuel burnup increase have been proved experimentally for the case of high-level serviceability maintenance of fuel elements to provide for advanced fuel cycles. (author)

VVER 1000-NPP Temelin safety upgrading

International Nuclear Information System (INIS)

Fleischhans, J.; Ubra, O.

1995-01-01

A modernisation program upgrading Temelin plant to meet internationally adopted standard has been implemented during plant design and construction phases. The initial Czech-Russian design (primary system was of Russian design, secondary system was of Czech design) has been extensively modified and adapted to present western safety criteria and operational requirements. The goals are to achieve a high level of safety, reliability, availability and load-following ability. The load-following ability and response to grid frequency changes are very important for the Czech Republic, since the nuclear capacity represents a high proportion of the overall electrical system there. On the basis of IAEA OSART missions and Halliburton NUS audit results and in compliance with recommendations of The State Office for Nuclear Safety, Czech Power Company and Czech scientists and researchers a modernisation program project for Temelin has been carried out. It includes three main groups of VVER1000 MW unit innovations: - Modernization and upgrading of the safety and control systems. - Fuel replacement and modification of the reactor core. - Innovation of some components of the primary and secondary systems. The tenders for instrumentation and control system, nuclear fuel, diagnostic system and radiation monitoring system were issued to the world-well known suppliers. The US company Westinghouse Electric >Corporation (WEC) was selected to submit contract for the delivery of instrumentation and control system primary side diagnostic system and for the delivery of nuclear fuel. The contract was signed in 1993

Comparison of radioactive doses after the last protection layer insight the reactor structure for Russian VVER-1000 and German PWR-1300 reactors

International Nuclear Information System (INIS)

Rahimi, A.; Mansourshaiflu, N.; Alizadeh, M. R.

2004-01-01

In pressurized reactors (VVER and PWR), various protections layers are used for reducing the output core doses. At any protection layer, some amount of neutron and gamma doses is reduced. In this project the axial flux of neutron and gamma beams have been evaluated at various protection layers in the operation state the German PWR-1300 and Russian VVER-1000 reactors by the MCNP computer code. For the purpose of effective use of the MCNP code and assuring its correct performance about of fluxed beams common and series of scientific answers and bench marks should be considered and the results obtained by the MCNP code, be compared with this answers. Then by using appropriate method, for reducing the flux variants of neutron and gamma beams at various protection layers of German PWR-1300 and Russian VVER-1000 reactors of the operation state of both reactors have been accelerated. In this projects, bench marks are computations and numbers existing in PSAR's present at Bushehr nuclear power plant. At the end, by using the results obtained and the standard doses, the time which a person can have work activity at the reactor wall (after the last protection layer), was compared for the operation status of the German PWR-1300 and Russian VVER-1000 reactors

CASTOR - Advanced System for VVER Steam Generator Inspection

International Nuclear Information System (INIS)

Mateljak, Petar

2014-01-01

From the safety point of view, steam generator is a very important component of a nuclear power plant. Only a thin tube wall prevents leakage of radioactive material from the primary side into the environment. Therefore, it is very important to perform inspections in order to detect pipe damage and apply appropriate corrective actions during outage. Application of the nondestructive examination (NDE) technique, that can locate degradation and measure its size and orientation, is an integral part of nuclear power plant maintenance. The steam generator inspection system is consisted of remotely controlled manipulator, testing instrument and software for data acquisition and analysis. Recently, the inspection systems have evolved to a much higher level of automation, efficiency and reliability resulting in a lower cost and shorter outage time. Electronic components have become smaller and deal with more complex algorithms. These systems are very fast, precise, reliable and easy to handle. The whole inspection, from the planning, examination, data analysis and final report, is now a highly automated process, which makes inspection much easier and more reliable. This paper presents the new generation of INETEC's VVER steam generator inspection system as ultimate solution for steam generator inspection and repair. (author)

Investigation of primary-to-secondary leakage accident on the PSB-VVER integral test facility

International Nuclear Information System (INIS)

Lipatov, I.A.; Dremin, G.I.; Galtchanskaya, S.A.; Chmal, I.I.; Moloshnikov, A.S.; Gorbunov, Y.S.; Antonova, A.I.; Elkin, I.V.

2001-01-01

The full text follows. The paper presents the main results from the test on primary-to-secondary leakage of 100 mm in equivalent diameter. The test was performed on the PSB-VVER integral test facility. PSB-VVER is a 4-loops scaled down model of primary system of NPP with VVER-1000 Russian type reactor. Volume - power scale is about 1/300 while elevation scale is 1/1. All components of the primary system of the reference NPP are modeled on PSB-VVER. Both passive (accumulators) and active (high and low pressure) ECCSs, pressurizer spray and relief circuits, feed water system and atmospheric dumping system (ADS) as well as the primary circuit gas remove emergency system are also simulated. The primary-to-secondary leakage was simulated using an external break line which connects the upper part of the hot header to SG water volume. The break line included a break nozzle (a cylindrical channel d = 5.8 mm, l/d = 10 with sharp inlet edge), quick-acting valve and two-phase mass flow rate measurement system. In addition loss of off-site power at the moment when a scram-signal is generated was assumed in the experiment. Thus the accident is to be considered as a beyond-design-basic one. The loss of off-site power results in the following: -main circulation pump shutdown; -pressurizer heaters switching off; -HPIS water cooling flow rate and number of points of water injection are reduced The study focuses on the adequacy of the associated accident management (AM) procedure developed by EDO ''GIDROPRESS'' as a General Designer of VVER-type reactors. The AM-procedure was adopted to the PSB-VVER test facility conditions using CATHARE (France) and DINAMIKA (Russia) codes analysis. The AM-procedure in PSB-VVER is as follows: after about 30 min of the onset of the accident, when the accident type and the localization of the SG affected become evident for the operator, he closes all the main steam isolation valves, inhibits the ADS actuation in the affected SG and begins to remove

Investigations of SPND noise signals in VVER-440 reactors

International Nuclear Information System (INIS)

Kiss, S.; Lipcsei, S.; Hazi, G.

2001-01-01

This paper describes and characterises SPND noise measurements of an operating VVER-440 nuclear reactor. Characteristics of the signal can be radically influenced by the geometrical properties of the detector and the cable and by the measuring arrangement. Structure of phase spectra showing propagating perturbations measured on uncompensated SPN detectors is studied through models.(author)

The status of the Bubbler Condenser Containment System for the Reactors of the VVER-440/213 Type

International Nuclear Information System (INIS)

Karwat, H.; Rosinger, H.E.

1998-01-01

VVER-440/213 Pressurized Water Reactors have a pressure-suppression containment structure called a 'Bubbler Condenser' tower which can reduce the design pressure of the entire containment following a design basis accident (DBA), such as a loss-of-coolant accident (LOCA). The bubbler condenser pressure suppression system provides reduction of the LOCA containment pressure by the condensation of released steam in a water pool. World-wide there are 14 nuclear power plants of the VVER-440/213 type in Eastern Europe and Russia. One of the safety concerns for the VVER-440/213 reactors relates to the ability of the bubbler condenser containment system to function satisfactorily and to maintain its integrity following certain postulated accidents and thus limit the release of radioactive material to the environment. The complicated geometry of the bubbler condenser unit, and the dependence on several moving devices and interlocks are the main doubts expressed by different specialists with regard to the design. General description of the bubbler condenser containment system, the physical processes, concerns and design assessment of the bubbler condenser containment system, presentation of the OECD's Unified Bubbler Condenser Research Project (UBCRP) and the European Commission PHARE/TACIS project. Recent utility investigations are also discussed

Validation of Advanced Computer Codes for VVER Technology: LB-LOCA Transient in PSB-VVER Facility

Directory of Open Access Journals (Sweden)

A. Del Nevo

2012-01-01

Full Text Available The OECD/NEA PSB-VVER project provided unique and useful experimental data for code validation from PSB-VVER test facility. This facility represents the scaled-down layout of the Russian-designed pressurized water reactor, namely, VVER-1000. Five experiments were executed, dealing with loss of coolant scenarios (small, intermediate, and large break loss of coolant accidents, a primary-to-secondary leak, and a parametric study (natural circulation test aimed at characterizing the VVER system at reduced mass inventory conditions. The comparative analysis, presented in the paper, regards the large break loss of coolant accident experiment. Four participants from three different institutions were involved in the benchmark and applied their own models and set up for four different thermal-hydraulic system codes. The benchmark demonstrated the performances of such codes in predicting phenomena relevant for safety on the basis of fixed criteria.

Upper plenum break LOCA investigation in the ISB-VVER and PSB-VVER facilities

Energy Technology Data Exchange (ETDEWEB)

Blinkov, V. N.; Melikhov, O. I.; Lipatov, I. A.; Nikonov, S. M.; Dremin, G. I.; Galchanskaya, S. A.; Gashenko, M. P.; Rovnov, A. A.; Kapustin, A. V.; Elkin, I. V. [EREC, Moscow (Russian Federation)

2003-07-01

The capability to define the actual NPP transient/accident scenario depends to a great extent on facilities' scaling and reliability of the system thermalhydraulic codes which, in turn, are assessed against the experimental data taken in the same facilities. At the present time, it is received fact that the rigorous modeling of the cumulative set of all thermalhydraulic processes in the plant primary and secondary sides during accident is unfeasible. Therefore, the extrapolation of the facilities loops behavior to the actual systems constitutes a fundamental problem in this area. In the paper, some aspects for the problem have been discussed in the course of comparative analysis of the data derived from the 11 % upper plenum break LOCA tests performed in the PSB-VVER and ISB-VVER integral test facilities under the close scenarios. Both facilities, PSB-VVER and ISB-VVER, are modeled the same VVER-1000 reactor in different scales. The thermalhydraulic behavior of the primary systems in both facilities has been discussed in the paper, and shown to be similar. Also, the attention has been focused upon the discrepancies in the significant variables trends. The discrepancies are shown to be caused by influence of peculiarities of the facilities hardware and due to the scale factor. The scaling study is an important aspect of the thermalhydraulic codes verification procedure. Being qualified against the experimentally simulated accident sequence in two test facilities of different scales, the thermalhydraulic codes will be capable of evaluation of the prototype behavior to greater accuracy.

VVER-1000: considering its strengths and weaknesses

International Nuclear Information System (INIS)

Laaksonen, J.

1994-01-01

The safety of currently operating VVER-1000 reactors is examined. The factors considered are deviations in operation, inherent safety, safety system design, protection against internal and external hazards, equipment quality, the approach to plant operations and the safety culture. On the basis of this evaluation it is concluded that the overall safety of a VVER-1000 cannot be at the level of a modern Western PWR though there is no sound basis to make a quantitative comparison. Many of the concerns raised are being adequately addressed in the Czech Temelin which is currently under construction and in new designs which are still at the drawing board stage. Extensive back fitting programmes are planned or underway in operating plants. The creation of independent responsible operating organizations, powerful regulation and an improved economic situation are advanced as necessary criteria for real improvements in safety. (UK)

Hextran-Smabre calculation of the VVER-1000 coolant transient benchmark

Energy Technology Data Exchange (ETDEWEB)

Elina Syrjaelahti; Anitta Haemaelaeinen [VTT Processes, P.O.Box 1604, FIN-02044 VTT (Finland)

2005-07-01

Full text of publication follows: The VVER-1000 Coolant Transient benchmark is intended for validation of couplings of the thermal hydraulic codes and three dimensional neutron kinetic core models. It concerns a switching on a main coolant pump when the other three main coolant pumps are in operation. Problem is based on experiment performed in Kozloduy NPP in Bulgaria. In addition to the real plant transient, two extreme scenarios concerning control rod ejection after switching on a main coolant pump were calculated. In VTT the three-dimensional advanced nodal code HEXTRAN is used for the core kinetics and dynamics, and thermohydraulic system code SMABRE as a thermal hydraulic model for the primary and secondary loop. Parallelly coupled HEXTRAN-SMABRE code has been in production use since early 90's, and it has been extensively used for analysis of VVER NPPs. The SMABRE input model is based on the standard VVER-1000 input used in VTT. Last plant specific modifications to the input model have been made in EU projects. The whole core calculation is performed in the core with HEXTRAN. Also the core model is based on earlier VVER-1000 models. Nuclear data for the calculation was specified in the benchmark. The paper outlines the input models used for both codes. Calculated results are introduced both for the coupled core system with inlet and outlet boundary conditions and for the whole plant model. Sensitivity studies have been performed for selected parameters. (authors)

Hextran-Smabre calculation of the VVER-1000 coolant transient benchmark

International Nuclear Information System (INIS)

Elina Syrjaelahti; Anitta Haemaelaeinen

2005-01-01

Full text of publication follows: The VVER-1000 Coolant Transient benchmark is intended for validation of couplings of the thermal hydraulic codes and three dimensional neutron kinetic core models. It concerns a switching on a main coolant pump when the other three main coolant pumps are in operation. Problem is based on experiment performed in Kozloduy NPP in Bulgaria. In addition to the real plant transient, two extreme scenarios concerning control rod ejection after switching on a main coolant pump were calculated. In VTT the three-dimensional advanced nodal code HEXTRAN is used for the core kinetics and dynamics, and thermohydraulic system code SMABRE as a thermal hydraulic model for the primary and secondary loop. Parallelly coupled HEXTRAN-SMABRE code has been in production use since early 90's, and it has been extensively used for analysis of VVER NPPs. The SMABRE input model is based on the standard VVER-1000 input used in VTT. Last plant specific modifications to the input model have been made in EU projects. The whole core calculation is performed in the core with HEXTRAN. Also the core model is based on earlier VVER-1000 models. Nuclear data for the calculation was specified in the benchmark. The paper outlines the input models used for both codes. Calculated results are introduced both for the coupled core system with inlet and outlet boundary conditions and for the whole plant model. Sensitivity studies have been performed for selected parameters. (authors)

VIPRE modeling of VVER-1000 reactor core for DNB analyses

Energy Technology Data Exchange (ETDEWEB)

Sung, Y.; Nguyen, Q. [Westinghouse Electric Corporation, Pittsburgh, PA (United States); Cizek, J. [Nuclear Research Institute, Prague, (Czech Republic)

1995-09-01

Based on the one-pass modeling approach, the hot channels and the VVER-1000 reactor core can be modeled in 30 channels for DNB analyses using the VIPRE-01/MOD02 (VIPRE) code (VIPRE is owned by Electric Power Research Institute, Palo Alto, California). The VIPRE one-pass model does not compromise any accuracy in the hot channel local fluid conditions. Extensive qualifications include sensitivity studies of radial noding and crossflow parameters and comparisons with the results from THINC and CALOPEA subchannel codes. The qualifications confirm that the VIPRE code with the Westinghouse modeling method provides good computational performance and accuracy for VVER-1000 DNB analyses.

Investigation of primary-to-secondary leakage accident on the PSB-VVER integral test facility

Energy Technology Data Exchange (ETDEWEB)

Lipatov, I.A.; Dremin, G.I.; Galtchanskaya, S.A.; Chmal, I.I.; Moloshnikov, A.S.; Gorbunov, Y.S.; Antonova, A.I. [Electrogorsk Research and Engineering Center, EREC, Moscow (Russian Federation); Elkin, I.V. [RRC ' ' Kurchatov Institute, Moscow (Russian Federation)

2001-07-01

The full text follows. The paper presents the main results from the test on primary-to-secondary leakage of 100 mm in equivalent diameter. The test was performed on the PSB-VVER integral test facility. PSB-VVER is a 4-loops scaled down model of primary system of NPP with VVER-1000 Russian type reactor. Volume - power scale is about 1/300 while elevation scale is 1/1. All components of the primary system of the reference NPP are modeled on PSB-VVER. Both passive (accumulators) and active (high and low pressure) ECCSs, pressurizer spray and relief circuits, feed water system and atmospheric dumping system (ADS) as well as the primary circuit gas remove emergency system are also simulated. The primary-to-secondary leakage was simulated using an external break line which connects the upper part of the hot header to SG water volume. The break line included a break nozzle (a cylindrical channel d = 5.8 mm, l/d = 10 with sharp inlet edge), quick-acting valve and two-phase mass flow rate measurement system. In addition loss of off-site power at the moment when a scram-signal is generated was assumed in the experiment. Thus the accident is to be considered as a beyond-design-basic one. The loss of off-site power results in the following: -main circulation pump shutdown; -pressurizer heaters switching off; -HPIS water cooling flow rate and number of points of water injection are reduced The study focuses on the adequacy of the associated accident management (AM) procedure developed by EDO ''GIDROPRESS'' as a General Designer of VVER-type reactors. The AM-procedure was adopted to the PSB-VVER test facility conditions using CATHARE (France) and DINAMIKA (Russia) codes analysis. The AM-procedure in PSB-VVER is as follows: after about 30 min of the onset of the accident, when the accident type and the localization of the SG affected become evident for the operator, he closes all the main steam isolation valves, inhibits the ADS actuation in the affected SG

Operational benchmark for VVER-1000, unit 6, Kozloduy NPP

International Nuclear Information System (INIS)

Apostolov, T.; Petrov, B.

1999-01-01

Benchmark calculations have been carried out using the 3D nodal code TRAPEZ. Global neutron-physics characteristics of the VVER-1000 core, Kozloduy NPP Unit 6, have been determined taking into account the real loading patterns and operational history of the first three cycles. The code TRLOAD has been used to perform the fuel reloading between any two cycles. The reactor and components descriptions as well as material compositions are given. The results presented include the critical boric acid concentration, the radial power distribution, the axial power distribution for the maximum overload assembly, and the burnup distribution at three different moments during each cycle. Calculated values have been compared with measured data. It is shown that the results obtained by the TRAPEZ code are in good agreement with the experimental data. The information presented could serve as a test case for validation of code packages designed for analyzing the steady-state operation of VVERs. (author)

Results of operation of VVER-1000 FAs manufactured at PJSC NCCP

International Nuclear Information System (INIS)

Davidov, D.; Brovkin, O.; Bezborodov, Y.

2015-01-01

Fuel Assemblies manufactured at PJSC NCCP are in operation at 27 VVER-1000 power units at 11 NPPs in Russia, Ukraine, Bulgaria, China, Iran and India. Basic results of operation of PJSC NCCP VVER-1000 FAs during 2007-2014 are presented. The operation results confirm the design characteristics of fuel, i.e.: average fuel burnup up to 55 MW*day/kgU in FAs; safe and reliable FA operation, with low leaking rate (in the order of 10-6). The achieved operation characteristics of TVSA and TVS-2M Fuel Assemblies prove the quality, reliability and competitiveness of FAs manufactured at PJSC NCCP

Neutron fluence measurement in the cavity of Balakovo nuclear power plant, unit 3

International Nuclear Information System (INIS)

Voorbraak, W.P.; Baard, J.H.; Paardekooper, A.; Nolthenius, H.J.

1996-12-01

An international benchmark exercise has been organized by the Russian GOSATOMNADZOR. The aim was to reduce the uncertainty of fluence measurements in Nuclear Power Plants in particular VVER-1000 reactors. The benchmark was set up in the cavity of the Balakovo NPP 3. Eight institutes were involved. This report presents the results obtained by ECN. From this report, it can be concluded that the results of the relative large monitor set (13 different reaction rates with overlapping response regions) point to possible imperfections in the calculated neutron spectra. However the experimental information is not powerful enough to reduce the uncertainty of the neutron fluence rate especially in the energy region between 0.1 and 0.5 MeV below 50 percent. (orig.)

New code for VVER-440 loading pattern design

International Nuclear Information System (INIS)

Bajgl, J.; Lehmann, M.

1999-01-01

This paper describes the main attributes of a new computer program OPTIMAL used for loading pattern design in Dukovany NPP (4 reactors VVER-440). We have been developed this program in Nuclear Research Institute Rez since 1994 on the base of special contract between Dukovany NPP and Nuclear Research Institute Rez. General information about the optimisation methodology is given in the first part. The organisation of the optimisation process is described in part 2. Construction of the optimisation functional is shown in part 3. Procedures used during one-cycle optimisation are described in part 4. (Authors)

The Role of Nuclear Power in Hungary, a Regional Comparison

International Nuclear Information System (INIS)

Cserhati, A.

2016-01-01

The presentation and paper are giving the broad picture on the country's nuclear competence and the atomic electricity production in international appraisal. The Central and Eastern Europe (CEE) region nuclear statistics were compiled by the author and appear in compact, easily understandable graphical form: Worldwide and regional figures of nuclear share for electricity generation. Types of operating nuclear power plant units. Age and performance (cumulative load factors) of units. Power uprate history of affected units. Status of the long term operation (or by earlier name: lifetime extension) projects. The cycle length expansion is a transition from 12 to 15 month fuel cycle, as a pioneering initiative of Paks NPP for efficiency increase of VVER-440 type. New build trends will be outlined in general for the world, Europe and the CEE region. The last topic is the Hungarian path to Paks-5 and Paks-6 completion. Preparatory projects (Teller and Levai), establishment of the Paks II company. Potential suppliers and types for the new build (AREVA EPR, ATMEA Atmea1, KEPCO/KHNP APR1400, Rosatom AES-2006, Toshiba-Westinghouse AP1000). Intergovernmental agreement with Russian Federation for building of two 1200 MW units. Financing of 80 percent of the investment by Russian loan with moderate interest rates. Planned schedule of the new build. EC infringement procedures. Public acceptance. (author).

Accident sequences simulated at the Juragua nuclear power plant

International Nuclear Information System (INIS)

Carbajo, J.J.

1998-01-01

Different hypothetical accident sequences have been simulated at Unit 1 of the Juragua nuclear power plant in Cuba, a plant with two VVER-440 V213 units under construction. The computer code MELCOR was employed for these simulations. The sequences simulated are: (1) a design-basis accident (DBA) large loss of coolant accident (LOCA) with the emergency core coolant system (ECCS) on, (2) a station blackout (SBO), (3) a small LOCA (SLOCA) concurrent with SBO, (4) a large LOCA (LLOCA) concurrent with SBO, and (5) a LLOCA concurrent with SBO and with the containment breached at time zero. Timings of important events and source term releases have been calculated for the different sequences analyzed. Under certain weather conditions, the fission products released from the severe accident sequences may travel to southern Florida

Validation studies of thermal-hydraulic code for safety analysis of nuclear power plants

International Nuclear Information System (INIS)

Haapalehto, T.

1995-01-01

The thesis gives an overview of the validation process for thermal-hydraulic system codes and it presents in more detail the assessment and validation of the French code CATHARE for VVER calculations. Three assessment cases are presented: loop seal clearing, core reflooding and flow in a horizontal steam generator. The experience gained during these assessment and validation calculations has been used to analyze the behavior of the horizontal steam generator and the natural circulation in the geometry of the Loviisa nuclear power plant. Large part of the work has been performed in cooperation with the CATHARE-team in Grenoble, France. (41 refs., 11 figs., 8 tabs.)

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

Development of TVSA VVER-1000 fuel

International Nuclear Information System (INIS)

Samoilov, O.; Kaydalov, V.; Romanov, A.; Falkov, A.; Morozkin, O.; Sholin, E.

2013-01-01

The TVSA fuel assemblies with a rigid angle-piece skeleton operate at 21 VVER-1000 units of Kalinin NPP, and Ukrainian, and Czech and Bulgarian NPPs. The total of more than 6,000 TVSA fuel assemblies have been fabricated. High lifetime performance has been achieved, namely, the maximum FA burnup is 65 MW∙day/kgU; maximum fuel rod burnup is 72 MW∙day/kgU; the lifetime is 50,000 EFPH. The TVSA fuel assembly is being improved to enhance its technical and economic performance and competitiveness of the Russian fuel for the VVER-1000 reactor: 1) Reliability and safety are being enhanced; repairability is being ensured. 2) High burnup levels in fuel are being ensured. 3) The uranium content in FAs is being increased. 4) The operational life is being extended. 5) Thermal-technical characteristics of FAs are being improved. The basic TVSA fuel assembly design evolved into the TVSA-PLUS with the fuel column elongated by 150 mm. The TVSA-PLUS fuel assembly has been in operation since 2010 at Kalinin NPP power units; an eighteen-month cycle is implemented at the uprated power of 104%. The TVSA-12PLUS fuel assembly has been developed with an elongated fuel column, optimized spacer grid positions (the spacer grid pitch is 340 mm) and with ensuring higher rigidity for the skeleton. It is provided for that fuel rods with the elevated uranium content and mixing intensifier grids will be used. The TVSA-T is developed for VVER-1000 reactor cores at the Temelin NPP. The TVSA-T is characterized by a load-carrying skeleton formed with angle-pieces and combined spacer grids that incorporate mixer grids. The TVSA-T design won the international tender to supply fuel to the Temelin NPP in the Czech Republic, and currently Temelin NPP Unit 1 and 2 are operating with the cores fully loaded with TVSA-Ts

Performance of water cooled nuclear power reactor fuels in India – Defects, failures and their mitigation

International Nuclear Information System (INIS)

Ganguly, Chaitanyamoy

2015-01-01

Water cooled and moderated nuclear power reactors account for more than 95% of the operating reactors in the world today. Light water reactors (LWRs) consisting of pressurized water reactor (PWR), their Russian counterpart namely VVER and boiling water reactor (BWR) will continue to dominate the nuclear power market. Pressurized heavy water reactor (PHWR), also known as CANDU, is the backbone of the nuclear power program in India. Updates on LWR and PHWR fuel performance are being periodically published by IAEA, OECD-NEA and the World Nuclear Association (WNA), highlighting fuel failure rate and the mitigation of fuel defects and failures. These reports clearly indicate that there has been significant improvement in in – pile fuel performance over the years and the present focus is to achieve zero fuel failure in high burn up and high performance fuels. The present paper summarizes the status of PHWR and LWR fuel performance in India, highlighting the manufacturing and the related quality control and inspection steps that are being followed at the PHWR fuel fabrication plant in order to achieve zero manufacturing defect which could contribute to achieving zero in – pile failure rate in operating and upcoming PHWR units in India. (author)

Design and neutronic investigation of the Nano fluids application to VVER-1000 nuclear reactor with dual cooled annular fuel

International Nuclear Information System (INIS)

Ansarifar, G.R.; Ebrahimian, M.

2016-01-01

Highlights: • The change in neutronic parameters to the use of nanofluid as coolant is presented. • Nanoparticle deposition on fuel clad is investigated. • Radial and axial local power peaking factors are presented. • ZrO 2 and Al 2 O 3 have the lowest rate of K eff drop off. - Abstract: Nowadays, many efforts have been made to improve the efficiency of nuclear power plants. One of which is use of the dual cooled annular fuel which is an internally and externally cooled annular fuel with many advantages in heat transfer characteristics. Another is the use of nanoparticle/water (nanofluid) as coolant. In this paper, by combining these two methods, the change in neutronic parameters of the VVER-1000 nuclear reactor core with dual cooled annular fuel attributable to the use of nanoparticle/water (nanofluid) as coolant is presented. Optimization of type and volume fraction of nanoparticles in water that affect the safety enhancement of core primary parameters is intended in this study. Reactivity change, radial and axial local power peaking factors (LPPF), and the consequence of nanoparticle deposition on fuel clad are investigated. As a result of changing the effective multiplication factor and PPF calculations for six types of nanoparticles which have been studied extensively for their heat transfer properties including Alumina, Aluminum, Copper oxide, Copper, Titania, and Zirconia with different volume fractions, it can be concluded that at low concentration (0.03 volume fraction), Zirconia and Alumina are the optimum nanoparticles for normal operation. The maximum radial and axial PPF are found to be invariant to the type of nanofluid at low volume fractions. With an increase in nanoparticle deposition thickness on the outer and inner clad, a flux and K eff depression occurred and ZrO 2 and Al 2 O 3 have the lowest rate of drop off.

Refurbishing the reactor protection systems of VVER-440/230 and VVER-1000/320 nuclear power plants with exclusively digital IandC systems

International Nuclear Information System (INIS)

Martin, M.

1997-01-01

The refurbishment of reactor protection systems of nuclear power plants is based on two sets of requirements: engineering aspects such as performance, qualification and licensing, as well as interfaces to other systems; and cost-benefit relationships, ease of service and maintenance as well as installation during scheduled outages. A number of WWER-440 and WWER-1000 nuclear plants have announced their intention to refurbish their protection systems. Since 1994, these plants have been placing orders with Siemens for new protection systems, including the neutron flux monitoring system utilizing the advanced system TELEPERM XS. This exclusively digital IandC system provides an excellent foundation for the remaining plant service life

Effect of uncompensated SPN detector cables on neutron noise signals measured in VVER-440 reactors

Energy Technology Data Exchange (ETDEWEB)

Kiss, S. E-mail: kisss@sunserv.kfki.hu; Lipcsei, S. E-mail: lipcsei@sunserv.kfki.hu; Hazi, G. E-mail: gah@sunserv.kfki.hu

2003-03-01

The Self Powered Neutron Detector (SPND) noise measurements of an operating VVER-440 nuclear reactor are described and characterised. Signal characteristics may be radically influenced by the geometrical properties of the detector and the cable, and by the measuring arrangement. Simulator is used as a means of studying the structure of those phase spectra that show propagating perturbations measured on uncompensated SPN detectors. The paper presents measurements with detectors of very different sizes (i.e. 20 cm length SPNDs and the 200 cm length compensation cables), where the ratios of the global and local component differ significantly for the different detector sizes. This phenomenon is used up for signal compensation.

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

Modernization programme for nuclear power plant units with VVER-1000 in Ukraine

International Nuclear Information System (INIS)

Shenderovich, V.

1997-01-01

All Ukrainian nuclear power plants with WWER type reactors are briefly described from the safety point of view. Information is given on the design and construction of the units. The main goals of upgrading are: elimination of incompliances with current safety standards, improvement of the reliability of safety significant systems, equipment and elements, and implementation of IAEA recommendations. A list of actions making up the large upgrading programme is given; it includes 181 measures to be taken. At present the measures are being designed in order to find appropriate engineering solutions, to develop technical specifications for new equipment, and to ensure precise cost estimation. (M.D.)

Present status and recent improvements of water chemistry at Russian VVER plants

International Nuclear Information System (INIS)

Mamet, V.; Yurmanov, V.

2001-01-01

Water chemistry is an important contributor to reliable plant operation, safety barrier integrity, plant component lifetime, radiation safety, environmental impact. Primary and secondary water chemistry guidelines of Russian VVER plants have been modified to meet the new safety standards. At present 14 VVER units of different generation are in operation at 5 Russian NPPs. There are eight 4-loop pressurised water reactors VVER-1000 (1000 MWe) and six 6-loop pressurised water reactors VVER-440 (440 MWe). Generally, water chemistry at East European VVER plants (about 40 VVER-440 and VVER-1000 units in Ukraine, Bulgaria, Slovakia, Czech Republic, Hungary, Finland and Armenia) is similar to water chemistry at Russian VVER plants. Due to similar design and structural materials some water chemistry improvements were introduced at East European plants after they has been successfully implemented at Russian plants and vice versa. Some water chemistry improvements will be implemented at modern VVER plants under construction in Ukraine, Slovakia, Czech Republic, Iran, China, India. (R.P.)

Radioactive release from VVER-1000 reactors after a terror attack

International Nuclear Information System (INIS)

Sdouz, G.

2005-01-01

Full text: One of the terror scenarios for nuclear power plants is a severe damage of the reactor containment caused by a plane crash or a missile. Due to the loss of electric power the cooling of the core is not maintained leading to a core melt accident. Normally in the course of severe accidents an intact containment has the ability to retain a large part of the radioactive inventory. The goal of this work is the investigation of the behavior of the radioactive release from a VVER-1000-type reactor during a severe accident with a large containment leak from the beginning of the accident. The results are compared with the release in a severe accident via a very small leakage due to the untightness of the containment. This work supplements a series of studies investigating the behavior of a VVER-1000-type reactor during severe accidents under different accident management strategies. The focus in this study is on the 'station blackout'-sequence (or TMLB' in the WASH-1400 nomenclature). The calculations were performed using the Source Term Code Package (STCP), hydrogen explosions are not considered. Up to the melt-through of the cavity bottom the thermal-hydraulics phenomena are almost identical to the TMLB'-case with an intact containment from the beginning. The phenomena occur slightly delayed due to the large containment leak. When the core-concrete-interaction begins the resulting gases leave the containment through the large leak and do not cause a pressure increase. The containment pressure remains at ambient pressure. Due to the different behavior and to the different release times of the nuclides the deviations to the scenario with an intact containment show a great variety. From this comparison it can be shown that the intact containment retains the nuclides up to a factor of 6000. (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)

The influence of changes in the VVER-1000 fuel assembly shape during operation on the power density distribution

Energy Technology Data Exchange (ETDEWEB)

Shishkov, L. K., E-mail: Shishkov-LK@nrcki.ru; Gorodkov, S. S.; Mikailov, E. F.; Sukhino-Homenko, E. A.; Sumarokova, A. S., E-mail: Sumarokova-AS@nrcki.ru [National Research Center Kurchatov Institute (Russian Federation)

2016-12-15

A new approach to calculation of the coefficients of sensitivity of the fuel pin power to deviations in gap sizes between fuel assemblies of the VVER-1000 reactor during its operation is proposed. It is shown that the calculations by the MCU code should be performed for a full-size model of the core to take the interference of the gap influence into account. In order to reduce the conservatism of calculations, the coolant density and coolant temperature feedbacks should be taken into account, as well as the fuel burnup.

Analysis of the VVER-440 reactor steam generator secondary side with the RELAP5/MOD3 code

International Nuclear Information System (INIS)

Tuunanen, J.

1993-01-01

Nuclear Engineering Laboratory of the Technical Research Centre of Finland has widely used RELAP5/MOD2 and -MOD3 codes to simulate horizontal steam generators. Several models have been developed and successfully used in the VVER-safety analysis. Nevertheless, the models developed have included only rather few nodes in the steam generator secondary side. The secondary side has normally been divided into about 10 to 15 nodes. Since the secondary side at the steam generators of VVER-440 type reactors consists of a rather large water pool, these models were only roughly capable to predict secondary side flows. The paper describes an attempt to use RELAP5/MOD3 code to predict secondary side flows in a steam generator of a VVER-440 reactor. A 2D/3D model has been developed using RELAP5/MOD3 codes cross-flow junctions. The model includes 90 volumes on the steam generator secondary side. The model has been used to calculate steady state flow conditions in the secondary side of a VVER-440 reactor steam generator. (orig.) (1 ref., 9 figs., 2 tabs.)

VVER-440 and VVER-1000 reactor dosimetry benchmark - BUGLE-96 versus ALPAN VII.0

International Nuclear Information System (INIS)

Duo, J. I.

2011-01-01

Document available in abstract form only, full text of document follows: Analytical results of the vodo-vodyanoi energetichesky reactor-(VVER-) 440 and VVER-1000 reactor dosimetry benchmarks developed from engineering mockups at the Nuclear Research Inst. Rez LR-0 reactor are discussed. These benchmarks provide accurate determination of radiation field parameters in the vicinity and over the thickness of the reactor pressure vessel. Measurements are compared to calculated results with two sets of tools: TORT discrete ordinates code and BUGLE-96 cross-section library versus the newly Westinghouse-developed RAPTOR-M3G and ALPAN VII.0. The parallel code RAPTOR-M3G enables detailed neutron distributions in energy and space in reduced computational time. ALPAN VII.0 cross-section library is based on ENDF/B-VII.0 and is designed for reactor dosimetry applications. It uses a unique broad group structure to enhance resolution in thermal-neutron-energy range compared to other analogous libraries. The comparison of fast neutron (E > 0.5 MeV) results shows good agreement (within 10%) between BUGLE-96 and ALPAN VII.O libraries. Furthermore, the results compare well with analogous results of participants of the REDOS program (2005). Finally, the analytical results for fast neutrons agree within 15% with the measurements, for most locations in all three mockups. In general, however, the analytical results underestimate the attenuation through the reactor pressure vessel thickness compared to the measurements. (authors)

Qualification of UT methods and systems used for in-service inspections of VVER 440 vessels

International Nuclear Information System (INIS)

Skala, Z.; Vit, J.

2003-01-01

SKODA JS has been performing automated in-service inspections VVER reactor pressure vessels for more than twenty years. All of these inspections were performed by ultrasonic pulse echo method, combined from 1996 with eddy current testing. The Time of Flight Diffraction Method (TOFD) is one of modern methods of ultrasonic testing. The accuracy of sizing the through wall extent of a flaw by TOFD is much better than the accuracy achievable by the pulse echo method. A series of laboratory tests were performed by SKODA JS and confirmed the suitability of TOFD method for VVER reactor parts testing. The Czech Atomic law demands the qualification of systems and methods used for the in-service inspections of nuclear reactors. The qualification is done in accordance with ENIQ methodology and consists of preparation of the Technical Justification and practical tests made under the surveillance of Qualification Body. SKODA JS intends to qualify systems and methods used for the automated ultrasonic testing of VVER 440 and VVER 1000 reactor components from the inner as well as from the outer surface. The accuracy of the flaw through wall extent sizing by TOFD was confirmed by the qualification of methods and systems used for the testing of VVER 440 vessel circumferential weld and so the TOFD method shall be used routinely by SKODA JS for the inspection of vessel circumferential welds root area and for sizing of flaws exceeding the acceptance level. (author)

Safety related investigations of the VVER-1000 reactor type by the coupled code system TRACE/PARCS

International Nuclear Information System (INIS)

Jaeger, Wadim; Lischke, Wolfgang; Sanchez Espinoza, Victor Hugo

2007-01-01

This study was performed at the Institute of Reactor Safety at the Research Center Karlsruhe. It is embedded in the ongoing investigations of the international code application and maintenance program (CAMP) for qualification and validation of system codes like TRACE [1] and PARCS [2]. The predestinated reactor type for the validation of these two codes was the Russian designed VVER-1000 because the OECD/NEA VVER-1000 Coolant Transient Benchmark Phase 2 [3] includes detailed information of the Bulgarian nuclear power plant (NPP) Kozloduy unit 6. The posttest-investigations of a coolant mixing experiment have shown that the predicted parameters (coolant temperature, pressure drop, etc.) are in good agreement to the measured data. The coolant mixing pattern especially in the downcomer has been also reproduced quiet well by TRACE. The coupled code system TRACE/PARCS which was applied on a postulated main steam line break (MSLB) provides good results compared to reference values and the ones of other participants of the benchmark. It can be pointed out that the developed three-dimensional nodalisation of the reactor pressure vessel (RPV) is appropriate for the description of transients where the thermal-hydraulics and the neutronics are strongly linked. (author)

The U.S.-Russian joint studies on using power reactors to disposition surplus weapons plutonium as spent fuel

International Nuclear Information System (INIS)

Chebeskov, A.; Kalashnikov, A.; Pavlovichev, A.

1997-09-01

In 1996, the US and the Russian Federation completed an initial joint study of the candidate options for the disposition of surplus weapons plutonium in both countries. The options included long term storage, immobilization of the plutonium in glass or ceramic for geologic disposal, and the conversion of weapons plutonium to spent fuel in power reactors. For the latter option, the US is only considering the use of existing light water reactors (LWRs) with no new reactor construction for plutonium disposition, or the use of Canadian deuterium uranium (CANDU) heavy water reactors. While Russia advocates building new reactors, the cost is high, and the continuing joint study of the Russian options is considering only the use of existing VVER-1000 LWRs in Russia and possibly Ukraine, the existing BN-60O fast neutron reactor at the Beloyarsk Nuclear Power Plant in Russia, or the use of the Canadian CANDU reactors. Six of the seven existing VVER-1000 reactors in Russia and the eleven VVER-1000 reactors in Ukraine are all of recent vintage and can be converted to use partial MOX cores. These existing VVER-1000 reactors are capable of converting almost 300 kg of surplus weapons plutonium to spent fuel each year with minimum nuclear power plant modifications. Higher core loads may be achievable in future years

Response of Soviet VVER-440 accident localization systems to overpressurization

International Nuclear Information System (INIS)

Kulak, R.F.; Fiala, C.; Sienicki, J.J.

1989-01-01

The Soviet designed VVER-440 model V230 and VVER-440 model V213 reactors do not use full containments to mitigate the effects of accidents. Instead, these VVER-440 units employ a sealed set of interconnected compartments, collectively called the accident localization system (ALS), to reduce the release of radionuclides to the atmosphere during accidents. Descriptions of the VVER accident localization structures may be found in the report DOE NE-0084. The objective of this paper is to evaluate the structural integrity of the VVER-440 ALS at the Soviet design pressure, and to determine their response to pressure loadings beyond the design value. Complex, three-dimensional, nonlinear, finite element models were developed to represent the major structural components of the localization systems of the VVER-440 models V230 and V213. The interior boundary of the localization system was incrementally pressurized in the calculations until the prediction of gross failure. 6 refs., 9 figs

VVER-440 training simulators upgrades - Experience of CORYS T.E.S.S

International Nuclear Information System (INIS)

Bartak, J.; Fallon, B.

2006-01-01

The paper presents recent projects of upgrading screen operated simulators of VVER-440 nuclear power plants to full scale replica simulators, implemented by CORYS TESS. Control room replica full scope simulators were built for the Bohunice NPP in Slovakia and the Novovoronezh NPP in Russia. The scope of simulation was extended to reflect the current status of the units, which have undergone significant modernization programs over the last few years. The paper describes the software and hardware adaptations and evolutions of the existing simulators, the implementation in the simulator of modern supervision systems as well as of systems and equipment designed in the seventies and still used on the reference units. The training benefits of parallel use of control room replica and screen-operated simulators in the training process are discussed. (author)

Estimation of material degradation of VVER-1000 baffle

Science.gov (United States)

Harutyunyan, Davit; Koš'ál, Michal; Vandlík, Stanislav; Hojná, Anna; Schulc, Martin; Flibor, Stanislav

2017-09-01

The planned lifetime of the first commercial VVER-1000 units were designed for 30 to 35 years. Most of the early VVER plants are now reaching and/or passing the 35-year mark. Service life extension for another 10 to 30 years is now under investigation. Life extension requires the evaluation of pressure vessel internals degradation under long-term irradiation. One of the possible limiting factors for the service life of VVERs is a void swelling of the Russian type titanium stabilized stainless 08Ch18N10T steel used to construct the baffle surrounding the core. This article aims to show first steps towards deeper analysis of the baffle degradation process and to demonstrate the possibilities of precise calculation and measurements on the VVER-1000 mock-up in LR-0 reactor.

Support of the Ukrainian supervisory authority in establishing a modern nuclear power plant monitoring

International Nuclear Information System (INIS)

Beyer, M.; Carl, H.; Schumann, P.; Seidel, A.; Weiss, F.P.; Zschau, J.; Nowak, K.

2000-01-01

The type of monitoring of nuclear power plants in Ukraine practiced in the early nineties provided the supervisory authority with only inadequate access to information about the current safety status of plants. For the Zaporozhye nuclear power plant, unit 5, a technical system to improve operational monitoring has been designed, installed and commissioned for trial operation at the end of 1995 as a pilot project. The system complements existing operational checking and monitoring facilities by including modern means of information technology. It enables concentration on a continuous monitoring of the state of unit 5 in normal operation and in cases of anormalies or incidents so that when recognisable deviations from the regular plant operation occur, the authority can immediately inquire and if necessary impose conditions on the operator. In 1997, the Information and Crisis Centre of the Ukraninian supervisory authority in Kiev was equipped with the most essential technical means necessary for quasi-simultaneous transfer of data and voice and for monitoring purposes and connected to the Centre to the Zaporozhye system. A similar monitoring system for both VVER-440 units of the Rovno nuclear power plant by analogy with the pilot project was specified and put into operation and connected to the ICC in 1998. (orig.) [de

Potential consequences in Norway after a hypothetical accident at Leningrad nuclear power plant. Potential release, fallout and predicted impacts on the environment

Energy Technology Data Exchange (ETDEWEB)

Nalbandyan, A.; Ytre-Eide, M.A.; Thoerring, H.; Liland, A.; Bartnicki, J.; Balonov, M.

2012-06-15

The report describes different hypothetical accident scenarios at the Leningrad nuclear power plant for both RBMK and VVER-1200 reactors. The estimated release is combined with different meteorological scenarios to predict possible fallout of radioactive substances in Norway. For a hypothetical catastrophic accident at an RBMK reactor combined with a meteorological worst case scenario, the consequences in Norway could be considerable. Foodstuffs in many regions would be contaminated above the food intervention levels for radioactive cesium in Norway. (Author)

Potential consequences in Norway after a hypothetical accident at Leningrad nuclear power plant. Potential release, fallout and predicted impacts on the environment

International Nuclear Information System (INIS)

Nalbandyan, A.; Ytre-Eide, M.A.; Thoerring, H.; Liland, A.; Bartnicki, J.; Balonov, M.

2012-06-01

The report describes different hypothetical accident scenarios at the Leningrad nuclear power plant for both RBMK and VVER-1200 reactors. The estimated release is combined with different meteorological scenarios to predict possible fallout of radioactive substances in Norway. For a hypothetical catastrophic accident at an RBMK reactor combined with a meteorological worst case scenario, the consequences in Norway could be considerable. Foodstuffs in many regions would be contaminated above the food intervention levels for radioactive cesium in Norway. (Author)

Completion of the VVER 440/213 NPP Mochovce incorporation enhanced safety features

International Nuclear Information System (INIS)

Charbonneau, S.; Eckert, G.

1996-01-01

The cooperation between the western countries and the countries of ex-eastern block in the field of nuclear safety is recent and still limited. The main reasons for this situation are limited or non existent capabilities of these countries for financing as well as non acceptable legal conditions concerning the third party nuclear liability in this part of Europe. Nevertheless, Framatome and Siemens associated in the consortium named EUCOM, have signed in April 1996 the contract of about 100 million US dollars with Slovak electricity company (SLOVENSKE ELEKTRARNE-SE) for upgrading the Units 1 and 2 of Mochovce Nuclear Power Plant according to the western safety standards. This is the first important project involving west-european companies in the modernisation of Russian type of pressurized water reactor (VVER 440/213). The consortium will cooperate with other partners involved in the project: Slovak, Czech and Russian. The financing of the project will be provided mainly form Slovak and Czech sources. The safety upgrading will be financed through French and German buyer credits. French company Electricite de France (EDF) will be the consultant for SE. The safety upgrading measures have been elaborated taking into account the recommendation of Vienna International Atomic Energy Agency (IAEA) and the evaluation of the safety realised by RISKAUDIT, the common organization of German and French safety authorities (GSR and IPSN). Hence all guaranties have been taken to fulfil the western safety criteria for Nuclear Power Plant Mochovce. (author)

Determination of power density in VVER-1000 Mock-Up in LR-0 reactor

Directory of Open Access Journals (Sweden)

Košál Michal

2017-01-01

Full Text Available The pin power density is an important quantity which has to be monitored during the reactor operation, for two main reasons. Firstly, it is part of the limits and conditions of safe operation and, secondly, it is source term in neutron transport calculations used for the adequate assessing of the state of core structures and pressure vessel material. It is often calculated using deterministic codes which may have problems with an adequate definition of boundary conditions in subcritical regions. This may lead to overestimation of real situation, and therefore the validation of the utility codes contributes not only to better fuel utilization, but also to more precise description of radiation situation in structural components of core. Current paper presents methods developed at LR-0 reactor, as well as selected results for pin power density measurement in peripheral regions of VVER-1000 mock-up. The presented data show that the results of a utility diffusion code at core boundary overestimate the measurement. This situation, however satisfactory safe, may lead to unduly conservative approach in the determination of radiation damage of core structures.

Nuclear power in eastern and central Europe. Background paper

International Nuclear Information System (INIS)

Myers, L.C.

1993-11-01

The breakup of the former Soviet Union and other political changes in eastern and central Europe have opened up the area to closer scrutiny than was previously possible. Because of the accident at Chernobyl, nuclear power is one of the subjects that western nations have had a great deal of interest in exploring. The former Soviet Union designed and/or helped build more than 60 civilian reactors in the region. Most of these reactors follow one of two distinctly different designs: the VVER, or pressurized water reactor series; and the RBMK, which is a graphite-moderated, multi-channel reactor (the so-called Chernobyl type). In addition, there are two fast-breeder reactors and four graphite-moderated boiling water reactors for combined heat and power in operation in Russia. These last two designs are not widely distributed and so are not discussed in detail in this report. As noted above, the safety of Soviet-designed reactors has been of great concern around the world since the catastrophic events at Chernobyl in 1986. This paper will briefly describe the technology involved. It will also examine the main safety concerns, both technical and organizational, associated with each reactor type. In addition, the paper will review the nuclear power programs in the new countries emerging from the former Soviet Union and its satellites and discuss the international efforts underway to address the most pressing problems. (author). 1 tab

Nuclear power in eastern and central Europe. Background paper

Energy Technology Data Exchange (ETDEWEB)

Myers, L C [Library of Parliament, Ottawa, ON (Canada). Science and Technology Div.

1993-11-01

The breakup of the former Soviet Union and other political changes in eastern and central Europe have opened up the area to closer scrutiny than was previously possible. Because of the accident at Chernobyl, nuclear power is one of the subjects that western nations have had a great deal of interest in exploring. The former Soviet Union designed and/or helped build more than 60 civilian reactors in the region. Most of these reactors follow one of two distinctly different designs: the VVER, or pressurized water reactor series; and the RBMK, which is a graphite-moderated, multi-channel reactor (the so-called Chernobyl type). In addition, there are two fast-breeder reactors and four graphite-moderated boiling water reactors for combined heat and power in operation in Russia. These last two designs are not widely distributed and so are not discussed in detail in this report. As noted above, the safety of Soviet-designed reactors has been of great concern around the world since the catastrophic events at Chernobyl in 1986. This paper will briefly describe the technology involved. It will also examine the main safety concerns, both technical and organizational, associated with each reactor type. In addition, the paper will review the nuclear power programs in the new countries emerging from the former Soviet Union and its satellites and discuss the international efforts underway to address the most pressing problems. (author). 1 tab.

BN-1200 Reactor Power Unit Design Development

International Nuclear Information System (INIS)

Vasilyev, B.A.; Shepelev, S.F.; Ashirmetov, M.R.; Poplavsky, V.M.

2013-01-01

Main goals of BN-1200 design: • Develop a reliable new generation reactor plant for the commercial power unit with fast reactor to implement the first-priority objectives in changing over to closed nuclear fuel cycle; • Improve technical and economic indices of BN reactor power unit to the level of those of Russian VVER of equal power; • Enhance the safety up to the level of the requirements for the 4th generation RP

Erosion-Corrosion Management System for secondary circuits of Nuclear Power Plants

International Nuclear Information System (INIS)

Butter, L.M.; Zeijseink, A.G.L.

2001-01-01

Erosion-corrosion in water steam systems is a corrosion mechanism that may develop undetected and results in unexpected damages. It is well known which chemical and physical parameters play an important role and what areas are usually affected. In order to facilitate this monitoring of Erosion-corrosion (EC) progress, KEMA has by order of the European Union Tacis-programme developed an Erosion-Corrosion Management System (ECMS) to improve control on the erosion-corrosion process, by improved data handling and analysis. This ECMS has been installed at the South Ukrainian Nuclear Power Plant (SUNPP) - VVER-1000. In general, it has been determined that the current ECMS helps by controlling the erosion-corrosion progress. The ECMS presents and analyses the results on an appropriate way. The recommendations are valuable. (R.P.)

Safety regulations regarding to accident monitoring and accident sampling at Russian NPPs with VVER type reactors

International Nuclear Information System (INIS)

Sharafutdinov, Rachet; Lankin, Michail; Kharitonova, Nataliya

2014-01-01

The paper describes a tendency by development of regulatory document requirements related to accident monitoring and accident sampling at Russia's NPPs. Lessons learned from the Fukushima Daiichi accident pointed at the importance and necessary to carry out an additional safety check at Russia's nuclear power plants in the preparedness for management of severe accidents at NPPs. Planned measures for improvement of severe accidents management include development and implementation of the accident instrumentation systems, providing, monitoring, management and storage of information in a severe accident conditions. The draft of Safety Guidelines <nuclear power plants with VVER reactors' prepared by Scientific and Engineering Centre for Nuclear and Radiation Safety (SEC NRS) established the main criteria for accident monitoring instrumentation that can monitor relevant plant parameters in the reactor and inside containment during and after a severe accident in nuclear power plants. Development of these safety guidelines is in line with the recommendations of IAEA Action Plan on Nuclear Safety in response to the Fukushima Daiichi event and recommendations of the IAEA Nuclear Energy series Report <Nuclear Power Plants' (Draft V 2.7). The paper presents the principles, which are used as the basis for selection of plant parameters for accident monitoring and for establishing of accident monitoring instrumentation. The recommendations to the accident sampling system capable to obtain the representative reactor coolant and containment air and fluid samples that support accurate analytical results for the parameters of interest are considered. The radiological and chemistry parameters to be monitored for primary coolant and sump and for containment air are specified. (author)

Validation of computer codes and modelling methods for giving proof of nuclear saefty of transport and storage of spent VVER-type nuclear fuels. Part 1. Purposes and goals of the project. Final report

International Nuclear Information System (INIS)

Buechse, H.; Langowski, A.; Lein, M.; Nagel, R.; Schmidt, H.; Stammel, M.

1995-01-01

The report gives the results of investigations on the validation of computer codes used to prove nuclear safety during transport and storage of spent VVER - fuel of NPP Greifswald and Rheinsberg. Characteristics of typical spent fuel (nuclide concentration, neutron source strength, gamma spectrum, decay heat) - calculated with several codes - and dose rates (e.g. in the surrounding of a loaded spent fuel cask) - based on the different source terms - are presented. Differences and their possible reasons are discussed. The results show that despite the differences in the source terms all relevant health physics requirements are met for all cases of source term. The validation of the criticality code OMEGA was established by calculation of appr. 200 critical experiments of LWR fuel, including VVER fuel rod arrangements. The mean error of the effective multiplication factor k eff is -0,01 compared to the experiment for this area of applicability. Thus, the OMEGA error of 2% assumed in earlier works has turned out to be sufficiently conservative. (orig.) [de

CFD analysis of flow distribution of reactor core and temperature rise of coolant in fuel assembly for VVER reactor

International Nuclear Information System (INIS)

Du Daiquan; Zeng Xiaokang; Xiong Wanyu; Yang Xiaoqiang

2015-01-01

Flow field of VVER-1000 reactor core was investigated by using computational fluid dynamics code CFX, and the temperature rise of coolant in hot assembly was calculated. The results show that the maximum value of flow distribution factor is 1.12 and the minimum value is 0.92. The average value of flow distribution factor in hot assembly is 0.97. The temperature rise in hot assembly is higher than current warning limit value ΔT t under the deviated operation condition. The results can provide reference for setting ΔT t during the operation of nuclear power plant. (authors)

Shut-down margin study for the next generation VVER-1000 reactor including 13 x 13 hexagonal annular assemblies

International Nuclear Information System (INIS)

Faghihi, Farshad; Mirvakili, S. Mohammad

2011-01-01

Highlights: → Shut-Down Margin (SDM) for the next generation annular fuel core of typical VVER-1000, 13 x 13 assemblies are calculated. → The MCNP-5 code is run for many cases with different core burn up at various core temperatures. → There is a substantial drop in SDM in the case of annular fuel for the same power level. → SDM for our proposed VVER-1000 annular pins is calculated for specific average fuel burn up values at the BOC, MOC, and EOC. - Abstract: Shut-Down Margin (SDM) for the next generation annular fuel core of typical VVER-1000, 13 x 13 assemblies are calculated as the main aim of the present research. We have applied the MCNP-5 code for many cases with different values of core burn up at various core temperatures, and therefore their corresponding coolant densities and boric acid concentrations. There is a substantial drop in SDM in the case of annular fuel for the same power level. Specifically, SDM for our proposed VVER-1000 annular pins is calculated when the average fuel burn up values at the BOC, MOC, and EOC are 0.531, 11.5, and 43 MW-days/kg-U, respectively.

Fuel for new Russian reactor VVER-1200

Energy Technology Data Exchange (ETDEWEB)

Vasilchenko, Ivan Nikitovich [GRPress, 21, Ordzhonikidze Street, 142103 Podolsk, Moscow region (Russian Federation)

2009-06-15

A great program is accepted in Russia on increasing the nuclear power capacities. The basis of the program is commissioning of VVER-1200 Units of AES-2006 design. This is largely an evolutionary project of VVER-1000 reactor plant. It is referred also to reactor core. The plant electric power is increased due to increase in the reactor thermal power and forcing the main parameters and the efficiency increase. With this, reactor pressure increases from 15,7 to 16,2 MPa. The reactor inlet temperature increases from 290 deg. C to 298 deg. C, and outlet temperature from 319 deg. C to 329 deg. C. In a set of the design for four Units (2 Units at Novovoronezh NPP and 2 Units at Leningrad NPP) two base fuel cycles are developed: 5 year and 3 year. To provide such fuel cycles the fuel loading is increased by 8 tons, as compared to VVER-1000 base design, due to fuel column increase by 200 mm and change of fuel pellet sizes. In the mentioned fuel cycles the average burnup in the unloaded batch will be {approx}57 MW.day/kg U and 52 MW.day/kg U (maximum burnup over FAs is 64,5 MW.day/kg U and 60,3 MW.day/kg U), respectively. Specific consumption of natural uranium will be reduced by 5% as compared to that reached at VVER-1000 reactor. In spite of increase in Unit power the limiting permissible fuel rod linear heat rate is decreased from 448 W/cm to 420 W/cm. Refueling pattern is used with small neutron escape. The safety criteria are used that were established for VVER-1000, except for those that did not comply with EUR. For instance, the number of leaky fuel rods under accident is limited. The more stringent requirements are stated on efficiency margin of CPS rods for reactor shutdown that is ensured by the increased number of CPS rods. The well-proved design of fuel assembly TVS-2 and its close modification TVS-2M, operated at Balakovo NPP and Rostov NPP, is laid down in the basis of the core design. The load-carrying component of this structure is a rigid skeleton formed by

Supply of appropriate nuclear technology for the developing world: small power reactors for electricity generation

International Nuclear Information System (INIS)

Heising-Goodman, C.D.

1981-01-01

This paper reviews the supply of small nuclear power plants (200 to 500 MWe electrical generating capacity) available on today's market, including the pre-fabricated designs of the United Kingdom's Rolls Royce Ltd and the French Alsthom-Atlantique Company. Also, the Russian VVER-440 conventionally built light-water reactor design is reviewed, including information on the Soviet Union's plans for expansion of its reactor-building capacity. A section of the paper also explores the characteristics of LDC electricity grids, reviewing methods available for incorporating larger plants into smaller grids as the Israelis are planning. Future trends in reactor supply and effects on proliferation rates are also discussed, reviewing the potential of the Indian 220 MWe pressurised heavy-water reactor, South Korean and Jananese potential for reactor exports in the Far East, and the Argentine-Brazilian nuclear programme in Latin America. This study suggests that small reactor designs for electrical power production and other applications, such as seawater desalination, can be made economical relative to diesel technology if traditional scaling laws can be altered by adopting and standardising a pre-fabricated nuclear power plant design. Also, economy can be gained if sufficient attention is concentrated on the design, construction and operating experience of suitably sized conventionally built reactor systems. (author)

Containment leak-tightness enhancement at VVER 440 NPPs

International Nuclear Information System (INIS)

Prandorfy, M.

2001-01-01

The hermetic compartments of VVER 440 NPPs fulfil the function of the containment used at NPPs all over the word. The purpose of the containment is to protect the NPP personal against radioactive impact as well as to prevent radioactive leakage to the environment during a lost of coolant accident. Leak-tightness enhancement in NPPs with VVER 440/213 and VVER 440/230 reactors is an important safety issue. New procedures, measures and methods were adopted at NPPs in Mochovce, J. Bohunice, Dukovany and Paks for leak identification and sealing works performed by VUEZ Levice. (authors)

Determination of mixing factors for VVER-440 fuel assembly head

Energy Technology Data Exchange (ETDEWEB)

Tóth, S., E-mail: toth@reak.bme.hu [Institute of Nuclear Techniques, Budapest University of Technology and Economics, Műegyetem rkp. 9, H-1111 Budapest (Hungary); Aszódi, A. [Institute of Nuclear Techniques, Budapest University of Technology and Economics, Műegyetem rkp. 9, H-1111 Budapest (Hungary)

2013-11-15

CFD models have been developed for the heads of the old, the present and the new type VVER-440 fuel assemblies using the experience of a former validation process. With these models temperature distributions are investigated in the heads of some typical assemblies and the in-core thermocouple signals are calculated. The analyses show that the coolant mixing is intensive but not-perfect in the assembly heads. The difference between the thermocouple signal and the cross-sectional average temperature at the measurement level depends on the assembly type. Using the results of these CFD calculations the weight factors of the rod bundle regions for the in-core thermocouple have been determined. With these factors the thermocouple signals are estimated and the results are statistically tested using the registered data of the Hungarian nuclear power plant. This test shows that the deviations between the measured and the calculated temperatures can be significantly decreased and consequently monitoring uncertainties can be reduced with using the weight factors.

Seismic assessment and upgrading of nuclear power plants in Eastern Europe

Energy Technology Data Exchange (ETDEWEB)

Katona, T; Kostov, M

1997-03-01

The basic findings of the seismic re-qualification programmes going on recently at all VVER plants in Eastern Europe can be summarised. The problems of the seismic safety have to be solved taking into account the general concept of the nuclear safety enhancement of the units. There are cases where the system improvements lead to better and more effective solution of the problem than the structural upgrading. The equipment and piping of the primary system have sufficient capacity. The viscous dampers are considered usually for the upgrading. The equipment anchorage especially the electrical and I and C equipment anchorage have to be upgraded. There are general consideration for replacement of the hydraulic snubbers by viscous dampers in the primary circuit of the VVER 440/V230. The considerations are not only because of the better seismic behaviour but mainly because of the better operational performance. There is relatively good seismic instrumentation at the plants considered. The definition of the scram level of the units not designed for an OBE is an essential problem. More effort needed for the definition of this level on the basis of re-evaluation experience of the plant equipment and after the proper definition of post-earthquake activities. The seismic re-evaluation and re-qualification of the VVER units is a general safety issue in Easter European countries. This rather complex problem can be solved adopting the experience, methods and requirements of western countries and taking into account the design features of the VVER units as well as the as built and as it is conditions. (J.P.N.)

Seismic assessment and upgrading of nuclear power plants in Eastern Europe

International Nuclear Information System (INIS)

Katona, T.; Kostov, M.

1997-01-01

The basic findings of the seismic re-qualification programmes going on recently at all VVER plants in Eastern Europe can be summarised. The problems of the seismic safety have to be solved taking into account the general concept of the nuclear safety enhancement of the units. There are cases where the system improvements lead to better and more effective solution of the problem than the structural upgrading. The equipment and piping of the primary system have sufficient capacity. The viscous dampers are considered usually for the upgrading. The equipment anchorage especially the electrical and I and C equipment anchorage have to be upgraded. There are general consideration for replacement of the hydraulic snubbers by viscous dampers in the primary circuit of the VVER 440/V230. The considerations are not only because of the better seismic behaviour but mainly because of the better operational performance. There is relatively good seismic instrumentation at the plants considered. The definition of the scram level of the units not designed for an OBE is an essential problem. More effort needed for the definition of this level on the basis of re-evaluation experience of the plant equipment and after the proper definition of post-earthquake activities. The seismic re-evaluation and re-qualification of the VVER units is a general safety issue in Easter European countries. This rather complex problem can be solved adopting the experience, methods and requirements of western countries and taking into account the design features of the VVER units as well as the as built and as it is conditions. (J.P.N.)

Isothermal and thermal–mechanical fatigue of VVER-440 reactor pressure vessel steels

Energy Technology Data Exchange (ETDEWEB)

Fekete, Balazs, E-mail: fekete.mm.bme@gmail.com [College of Dunaujvaros, Tancsics 1A, Dunaujvaros H-2400 (Hungary); Department of Applied Mechanics, Budapest University of Technology and Economics, Muegyetem 5, Budapest H-1111 (Hungary); Trampus, Peter [College of Dunaujvaros, Tancsics 1A, Dunaujvaros H-2400 (Hungary)

2015-09-15

Highlights: • We aimed to determine the thermomechanical behaviour of VVER reactor steels. • Material tests were developed and performed on GLEEBLE 3800 physical simulator. • Coffin–Manson curves and parameters were derived. • High accuracy of the strain energy based evaluation was found. • The observed dislocation evolution correlates with the mechanical behaviour. - Abstract: The fatigue life of the structural materials 15Ch2MFA (CrMoV-alloyed ferritic steel) and 08Ch18N10T (CrNi-alloyed austenitic steel) of VVER-440 reactor pressure vessel under completely reserved total strain controlled low cycle fatigue tests were investigated. An advanced test facility was developed for GLEEBLE-3800 physical simulator which was able to perform thermomechanical fatigue experiments under in-service conditions of VVER nuclear reactors. The low cycle fatigue results were evaluated with the plastic strain based Coffin–Manson law, and plastic strain energy based model as well. It was shown that both methods are able to predict the fatigue life of reactor pressure vessel steels accurately. Interrupted fatigue tests were also carried out to investigate the kinetic of the fatigue evolution of the materials. On these samples microstructural evaluation by TEM was performed. The investigated low cycle fatigue behavior can provide reference for remaining life assessment and lifetime extension analysis.

Developing a computational tool for predicting physical parameters of a typical VVER-1000 core based on artificial neural network

International Nuclear Information System (INIS)

Mirvakili, S.M.; Faghihi, F.; Khalafi, H.

2012-01-01

Highlights: ► Thermal–hydraulics parameters of a VVER-1000 core based on neural network (ANN), are carried out. ► Required data for ANN training are found based on modified COBRA-EN code and then linked each other using MATLAB software. ► Based on ANN method, average and maximum temperature of fuel and clad as well as MDNBR of each FA are predicted. -- Abstract: The main goal of the present article is to design a computational tool to predict physical parameters of the VVER-1000 nuclear reactor core based on artificial neural network (ANN), taking into account a detailed physical model of the fuel rods and coolant channels in a fuel assembly. Predictions of thermal characteristics of fuel, clad and coolant are performed using cascade feed forward ANN based on linear fission power distribution and power peaking factors of FAs and hot channels factors (which are found based on our previous neutronic calculations). A software package has been developed to prepare the required data for ANN training which applies a modified COBRA-EN code for sub-channel analysis and links the codes using the MATLAB software. Based on the current estimation system, five main core TH parameters are predicted, which include the average and maximum temperatures of fuel and clad as well as the minimum departure from nucleate boiling ratio (MDNBR) for each FA. To get the best conditions for the considered ANNs training, a comprehensive sensitivity study has been performed to examine the effects of variation of hidden neurons, hidden layers, transfer functions, and the learning algorithms on the training and simulation results. Performance evaluation results show that the developed ANN can be trained to estimate the core TH parameters of a typical VVER-1000 reactor quickly without loss of accuracy.

Nuclear safety evaluation of the VVER 440, Type 213

International Nuclear Information System (INIS)

Urbancik, L.

1997-01-01

The supervisory activities of the State Office for Nuclear Safety at the Dukovany nuclear power plant are described. No event resulting in an inpermissible radioactivity leak into the environment occurred at the plant in 1996. From among the 76 failures and events having occurred, only 4 were classified as level 1 on the International Nuclear Event Scale. Changes in the technology of radioactive waste bituminization were proposed. The Interim Spent Fuel Storage Facility at the Dukovany site was in test operation in 1996. Selected physical parameters of this facility were monitored. Seven international transports of spent fuel were accomplished in 1996. The dose rates in the surroundings of the Dukovany plant are monitored constantly by a teledosimetric system operated by the nuclear power plant. Periodical sampling and radionuclide activity measurements in the environment are also performed. (M.D.)

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.

The design of PSB-VVER experiments relevant to accident management

International Nuclear Information System (INIS)

Del Nevo, Alessandro; D'auria, Francesco; Mazzini, Marino; Bykov, Michael; Elkin, Ilya V.; Suslov, Alexander

2008-01-01

Experimental programs carried-out in integral test facilities are relevant for validating the best estimate thermal-hydraulic codes, which are used for accident analyses, design of accident management procedures, licensing of nuclear power plants, etc. The validation process, in fact, is based on well designed experiments. It consists in the comparison of the measured and calculated parameters and the determination whether a computer code has an adequate capability in predicting the major phenomena expected to occur in the course of transient and/or accidents. University of Pisa was responsible of the numerical design of the 12 experiments executed in PSB-VVER facility, operated at Electrogorsk Research and Engineering Center (Russia), in the framework of the TACIS 2.03/97 Contract 3.03.03 Part A, EC financed. The paper describes the methodology adopted at University of Pisa, starting form the scenarios foreseen in the final test matrix until the execution of the experiments. This process considers three key topics: a) the scaling issue and the simulation, with unavoidable distortions, of the expected performance of the reference nuclear power plants; b) the code assessment process involving the identification of phenomena challenging the code models; c) the features of the concerned integral test facility (scaling limitations, control logics, data acquisition system, instrumentation, etc.). The activities performed in this respect are discussed, and emphasis is also given to the relevance of the thermal losses to the environment. This issue affects particularly the small scaled facilities and has relevance on the scaling approach related to the power and volume of the facility. (author)

The Design of PSB-VVER Experiments Relevant to Accident Management

Science.gov (United States)

Nevo, Alessandro Del; D'Auria, Francesco; Mazzini, Marino; Bykov, Michael; Elkin, Ilya V.; Suslov, Alexander

Experimental programs carried-out in integral test facilities are relevant for validating the best estimate thermal-hydraulic codes(1), which are used for accident analyses, design of accident management procedures, licensing of nuclear power plants, etc. The validation process, in fact, is based on well designed experiments. It consists in the comparison of the measured and calculated parameters and the determination whether a computer code has an adequate capability in predicting the major phenomena expected to occur in the course of transient and/or accidents. University of Pisa was responsible of the numerical design of the 12 experiments executed in PSB-VVER facility (2), operated at Electrogorsk Research and Engineering Center (Russia), in the framework of the TACIS 2.03/97 Contract 3.03.03 Part A, EC financed (3). The paper describes the methodology adopted at University of Pisa, starting form the scenarios foreseen in the final test matrix until the execution of the experiments. This process considers three key topics: a) the scaling issue and the simulation, with unavoidable distortions, of the expected performance of the reference nuclear power plants; b) the code assessment process involving the identification of phenomena challenging the code models; c) the features of the concerned integral test facility (scaling limitations, control logics, data acquisition system, instrumentation, etc.). The activities performed in this respect are discussed, and emphasis is also given to the relevance of the thermal losses to the environment. This issue affects particularly the small scaled facilities and has relevance on the scaling approach related to the power and volume of the facility.

Generation of multigroup cross-sections from micro-group ones in code system SUHAM-U used for VVER-1000 reactor core calculations with MOX loading

Energy Technology Data Exchange (ETDEWEB)

Boyarinov, V.F.; Davidenko, V.D.; Polismakov, A.A.; Tsybulsky, V.F. [RRC Kurchatov Institute, Moscow (Russian Federation)

2005-07-01

At the present time, the new code system SUHAM-U for calculation of the neutron-physical processes in nuclear reactor core with triangular and square lattices based both on the modern micro-group (about 7000 groups) cross-sections library of code system UNK and on solving the multigroup (up to 89 groups) neutron transport equation by Surface Harmonics Method is elaborated. In this paper the procedure for generation of multigroup cross-sections from micro-group ones for calculation of VVER-1000 reactor core with MOX loading is described. The validation has consisted in computing VVER-1000 fuel assemblies with uranium and MOX fuel and has shown enough high accuracy under corresponding selection of the number and boundaries of the energy groups. This work has been fulfilled in the frame of ISTC project 'System Analyses of Nuclear Safety for VVER Reactors with MOX Fuels'.

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.)

PSB-VVER counterpart experiment simulating a small cold leg break LOCA

International Nuclear Information System (INIS)

Blinkov, V.N.; Melikhov, O.I.; Kapustin, A.V.; Lipatov, I.A.; Dremin, G.I.; Nikonov, S.M.; Rovnov, A.A.; Elkin, I.V.; Pylev, S.S.

2005-01-01

Full text of publication follows: An experiment simulating a small break LOCA has been performed in PSB-VVER facility, under PSB-VVER OECD Project. The test is intended to be a counterpart one to an experiment performed in the LOBI integral test facility. The objectives of the PSB-VVER small cold leg break test are: to study VVER-1000 thermal hydraulic response following a small break in the cold leg, to provide data for code assessment regarding phenomena indicated in the VVER-1000 code validation matrix and to study the scaling effect. The scenario for the PSB-VVER experiment has been designed taking the LOBI BL-34 test as reference. The ratio of primary system volumes (without volume of the pressurizer and the surge line) has been chosen to scale the reference experiment conditions and to generate the conditions of PSB-VVER cold leg break experiment. The resulting conditions are compared with the LOBI cold leg break test conditions by means of different counterpart test criteria. Comparing the two experiments in terms of the criteria shows that basic requirements to the counterpart test are fulfilled. A pretest analysis with RELAP5/MOD3.2 code has shown that the PSBVVER small break experiment is expected to show the same relevant phenomena and main events as the LOBI BL-34 test. The predicted PSB-VVER primary pressure is very close to that measured in the LOBI facility. The measured pressure in the PSB-VVER primary system has turned out to be very close to that registered in LOBI BL-34 test. This verifies the approach used for developing the conditions of the PSB-VVER counterpart test. The experiment results and the RELAP5/MOD3.2 pretest calculation are in good agreement. A posttest calculation of the experiment with RELAP5/MOD3.2 code has been performed in order to assess the codes capability to simulate the phenomena relevant to the test. The code has shown a reasonable prediction of the phenomena measured in the experiment. (authors)

PSB-VVER counterpart experiment simulating a small cold leg break LOCA

Energy Technology Data Exchange (ETDEWEB)

Blinkov, V.N.; Melikhov, O.I.; Kapustin, A.V.; Lipatov, I.A.; Dremin, G.I.; Nikonov, S.M.; Rovnov, A.A. [Elektrogorsk Research and Engineering Center, EREC, Bezymiannaja Street, 6, Elektrogorsk, Moscow Region, 142530 (Russian Federation); Elkin, I.V.; Pylev, S.S. [NSI RRC ' Kurchatov Institute' , Kurchatov Sq., 1, Moscow, 123182 (Russian Federation)

2005-07-01

Full text of publication follows: An experiment simulating a small break LOCA has been performed in PSB-VVER facility, under PSB-VVER OECD Project. The test is intended to be a counterpart one to an experiment performed in the LOBI integral test facility. The objectives of the PSB-VVER small cold leg break test are: to study VVER-1000 thermal hydraulic response following a small break in the cold leg, to provide data for code assessment regarding phenomena indicated in the VVER-1000 code validation matrix and to study the scaling effect. The scenario for the PSB-VVER experiment has been designed taking the LOBI BL-34 test as reference. The ratio of primary system volumes (without volume of the pressurizer and the surge line) has been chosen to scale the reference experiment conditions and to generate the conditions of PSB-VVER cold leg break experiment. The resulting conditions are compared with the LOBI cold leg break test conditions by means of different counterpart test criteria. Comparing the two experiments in terms of the criteria shows that basic requirements to the counterpart test are fulfilled. A pretest analysis with RELAP5/MOD3.2 code has shown that the PSBVVER small break experiment is expected to show the same relevant phenomena and main events as the LOBI BL-34 test. The predicted PSB-VVER primary pressure is very close to that measured in the LOBI facility. The measured pressure in the PSB-VVER primary system has turned out to be very close to that registered in LOBI BL-34 test. This verifies the approach used for developing the conditions of the PSB-VVER counterpart test. The experiment results and the RELAP5/MOD3.2 pretest calculation are in good agreement. A posttest calculation of the experiment with RELAP5/MOD3.2 code has been performed in order to assess the codes capability to simulate the phenomena relevant to the test. The code has shown a reasonable prediction of the phenomena measured in the experiment. (authors)

Data analysis treatment in the Juragua Nuclear Power Plant preoperational PSA

International Nuclear Information System (INIS)

Valhuerdi Debesa, C.

1996-01-01

Data Analysis is an important task within Probabilistic safety Assessment,. which usually determines the level of detail of the analysis, being the way to feed the PSA with the operational experience of the Nuclear Power Plant analysed. In this paper the role of the Data Analysis Task as part of the PSA process and the different kinds of data to be estimated are explained. A description is presented of the organization of the data Analysis in the Juragua NPP Preoperational PSA, the information sources and the criteria handled for the estimation of the different kinds of Data. The Generic Data Base adopted for equipment failures and the state of the generic data issue for VVER reactors and its prospects are also dealt with. The paper concludes with suggestions for the further development of Juragua NPP generic Data Base

3D analysis of the reactivity insertion accident in VVER-1000

Energy Technology Data Exchange (ETDEWEB)

Abdullayev, A. M.; Zhukov, A. I.; Slyeptsov, S. M. [NSC Kharkov Inst. for Physics and Technology, 1, Akademicheskaya Str., Kharkov 61108 (Ukraine)

2012-07-01

Fuel parameters such as peak enthalpy and temperature during rod ejection accident are calculated. The calculations are performed by 3D neutron kinetics code NESTLE and 3D thermal-hydraulic code VIPRE-W. Both hot zero power and hot full power cases were studied for an equilibrium cycle with Westinghouse hex fuel in VVER-1000. It is shown that the use of 3D methodology can significantly increase safety margins for current criteria and met future criteria. (authors)

Investigation on accident management measures for VVER-1000 reactors

International Nuclear Information System (INIS)

Tusheva, P.; Schaefer, F.; Rohde, U.; Reinke, N.

2009-01-01

A consequence of a total loss of AC power supply (station blackout) leading to unavailability of major active safety systems which could not perform their safety functions is that the safety criteria ensuring a secure operation of the nuclear power plant would be violated and a consequent core heat-up with possible core degradation would occur. Currently, a study which examines the thermal-hydraulic behaviour of the plant during the early phase of the scenario is being performed. This paper focuses on the possibilities for delay or mitigation of the accident sequence to progress into a severe one by applying Accident Management Measures (AMM). The strategy 'Primary circuit depressurization' as a basic strategy, which is realized in the management of severe accidents is being investigated. By reducing the load over the vessel under severe accident conditions, prerequisites for maintaining the integrity of the primary circuit are being created. The time-margins for operators' intervention as key issues are being also assessed. The task is accomplished by applying the GRS thermal-hydraulic system code ATHLET. In addition, a comparative analysis of the accident progression for a station blackout event for both a reference German PWR and a reference VVER-1000, taking into account the plant specifics, is being performed. (authors)

Influence of Bypass on Thermo-Hydraulics of VVER 440 Fuel Assembly

Directory of Open Access Journals (Sweden)

Jakubec Jakub

2017-04-01

Full Text Available The paper deals with CFD modelling and simulation of coolant flow within the nuclear reactor VVER 440 fuel assembly. The influence of coolant flow in bypass on the temperature distribution at the outlet of the fuel assembly and pressure drop was investigated. Only steady-state analyses were performed. Boundary conditions are based on operating conditions. ANSYS CFX is chosen as the main CFD software tool, where all analyses are performed.

Basket criticality design of a dual purpose cask for VVER 1000 spent fuel assemblies

Energy Technology Data Exchange (ETDEWEB)

Rezaeian, Mahdi [Nuclear Science and Technology Research Institute, Tehran (Iran, Islamic Republic of); Kamali, Jamshid [Atomic Energy Organization of Iran (AEOI), Tehran (Iran, Islamic Republic of)

2016-12-15

Dual purpose cask technology is one of the most prominent options for interim storage of spent fuels following their removal from reactors. Criticality safety of the spent fuel assemblies are ensured by design of the basket within these casks. In this study, a set of criticality design calculations of a dual purpose cask for 12 VVER 1000 spent fuel assemblies of Bushehr nuclear power plant were carried out. The basket material of borated stainless steel with 0.5 to 2.5 wt% of boron and Boral (Al-B{sub 4}C) with 1.5 to 40 wt% of boron carbide, were investigated and the minimum required receptacle pitch of the basket was determined. Using the calculated receptacle pitch of the basket, the minimum required diameter of the cavity could be established.

Investigation of reliability of EC method for inspection of VVER steam generator tubes

International Nuclear Information System (INIS)

Corak, Z.

2004-01-01

performance demonstration program is not yet as advanced for ECT of VVER SG tubes as it is for PWR SG tubes. There are great differences between countries with VVER operated nuclear power plants. Some of the countries have not even started similar activities, while some of them conducted a performance demonstration on artificial flaws including artificial corrosion. VNIAES, Gidropress and INETEC-Institute for Nuclear Technology have started up a project to develop a database similar as it is done by EPRI for PWR by real samples of steam generator tubes. The paper will present main activities regarding the above mentioned project.(author)

Reflooding and boil-off experiments in a VVER-440 like rod bundle and analyses with the CATHARE code

International Nuclear Information System (INIS)

Korteniemi, V.; Haapalehto, T.; Puustinen, M.

1995-01-01

Several experiments were performed with the VEERA facility to simulate reflooding and boil-off phenomena in a VVER-440 like rod bundle. The objective of these experiments was to get experience of a full-scale bundle behavior and to create a database for verification of VVER type core models used with modern thermal-hydraulic codes. The VEERA facility used in the experiments is a scaled-down model of the Russian VVER-440 type pressurized water reactors used in Loviisa, Finland. The test section of the facility consists of one full-scale copy of a VVER-440 reactor rod bundle with 126 full-length electrically heated rod simulators. Bottom and top-down reflooding, different modes of emergency core cooling (ECC) injection and the effect of heating power on the heat-up of the rods was studied. In this paper the results of calculations simulating two reflood and one boil-off experiment with the French CATHARE2 thermal-hydraulic code are also presented. Especially the performance of the recently implemented top-down reflood model of the code was studied

Reflooding and boil-off experiments in a VVER-440 like rod bundle and analyses with the CATHARE code

Energy Technology Data Exchange (ETDEWEB)

Korteniemi, V.; Haapalehto, T. [Lappeenranta Univ. of Technology (Finland); Puustinen, M. [VTT Energy, Lappeenranta (Finland)

1995-09-01

Several experiments were performed with the VEERA facility to simulate reflooding and boil-off phenomena in a VVER-440 like rod bundle. The objective of these experiments was to get experience of a full-scale bundle behavior and to create a database for verification of VVER type core models used with modern thermal-hydraulic codes. The VEERA facility used in the experiments is a scaled-down model of the Russian VVER-440 type pressurized water reactors used in Loviisa, Finland. The test section of the facility consists of one full-scale copy of a VVER-440 reactor rod bundle with 126 full-length electrically heated rod simulators. Bottom and top-down reflooding, different modes of emergency core cooling (ECC) injection and the effect of heating power on the heat-up of the rods was studied. In this paper the results of calculations simulating two reflood and one boil-off experiment with the French CATHARE2 thermal-hydraulic code are also presented. Especially the performance of the recently implemented top-down reflood model of the code was studied.

Nuclear energy industry in Russia promoting global strategy

International Nuclear Information System (INIS)

Kobayashi, Masaharu

2001-01-01

Since former USSR disintegrated to birth new Russia on December, 1991, it already passed ten years. As Russian economic hardship affected its nuclear energy development, No.1 reactor of the Rostov nuclear power station (VVER-1000) established its full power operation on September, 2001 after passing eight years of pausing period as a Russian nuclear power station, at dull development of nuclear energy in the world. When beginning of its commercial operation, scale of nuclear power generation under operation in Russia will reach to the fourth one in the world by getting over the one in Germany. Russia also begins international business on reprocessing of spent fuel and intermittent storage. And, Russia positively develops export business of concentrated uranium and nuclear fuel, too. Furthermore, Russia shows some positive initiatives on export of nuclear power station to China, Iran and India, and development on advanced nuclear reactor and nuclear fuel cycle forecast to future. Here was introduced on international developmental development of nuclear energy industry activated recently at delayed time for this ten years. (G.K.)

Lifetime-management and lifetime-extension at PAKS nuclear power plant

International Nuclear Information System (INIS)

Katona, Tamas; Ratkai, Sandor; Janosi, Agnes Biro

2002-01-01

Paks Nuclear Power Plant provides 38-40% of domestic generation at lowest price. It has an important energy-policy role in Hungary. NPP Paks shall be a decisive and perspectively permanent element of the domestic electricity generation during the next two decades, which shall be ensured by plant safe operation, the lifetime extension and power uprating. Paks Nuclear Power Plant investigated the nuclear power plant's lifetime extension possibilities and alternatives, as well as technical and business feasibility of such alternatives. The feasibility study is based on the evaluation of a representative set of systems, structures and components, operational, test, in-service inspection and maintenance practice, experience and findings of the Periodic Safety Review. The most important results of this study showing the feasibility of 20 years lifetime extension is summarised in the paper. It was found that there are no technical or safety issues or limits, which may inhibit the operation of the Nuclear Power Plant Paks up to 50 years. In case of most systems and equipment the recent monitoring, maintenance and regular reconstruction practice of the NPP Paks allows the lifetime extension without outstanding cost. Replacement or reconstruction of a few equipment and systems requires significant investment costs. Material of reactor vessels of VVER/213 incorporated at Paks, compared to vessels of the similar units, is less sensitive to the embrittlement. At units 3-4 reactor vessels do not require any measure, consequently, any additional cost, even in case of a lifetime of 50 years. At unit 2 to extend the lifetime of the reactor vessel, only heating-up of emergency core cooling tanks is needed in order to decrease thermal stress levels caused by pressure thermal shock (PST) transients. For this purpose cost-effective technical solutions are available. At unit 1, beside the heating-up of the emergency core cooling tanks annealing of the welded joint No. 5/6 close to the

Anchorage of equipment - requirements and verification methods with emphasis on equipment of existing and constructed VVER-type nuclear power plants

International Nuclear Information System (INIS)

Masopust, R.

1999-01-01

Criteria and verification methods which are recommended for use in the capacity evaluation of anchorage of safety-related equipment at WWER-type nuclear power plants are presented. Developed in compliance with the relevant basic standards documents specifically for anchorage of WWER-type equipment components, the criteria and methods cover different types of anchor bolts and other anchorage elements which are typical of existing, constructed, or reconstructed WWER-type nuclear power plants

Feasibility of VVER-440 type SFAT

International Nuclear Information System (INIS)

Kaartinen, J.; Tarvainen, M.

1995-05-01

Spent fuel attribute tester, SFAT, has been constructed and tested for gross defect verification of VVER-440 type spent fuel assemblies. Based on earlier optimisation studies, the VVER-440 SFAT is kept hanging from the mast of the fuel handling machine moved by the operator. The device tested includes a standard 2' x 2' NaI(T1) detector connected to a commercial MCA. The results achieved with normal VVER-440 spent fuel assemblies at the Loviisa npp in Finland in November 1994 show that the method is feasible. The design of the so-called fuel follower assemblies, however, prevents SFAT verification, at least with moderate measurement times. Verification of the presence of the assemblies based on the detection of the fission product 137 Cs (662 keV) is possible even in 10-30 seconds. Measurement times of the order of 1-2 minutes make it possible to draw also semi-quantitative conclusions of the burnup and cooling time of the operator declared data (consistency check). (orig.) (7 refs., 11 figs., 3 tabs.)

Fuel designs for VVER reactors

International Nuclear Information System (INIS)

Simonov, K.V.; Carbon, P.; Silberstein, A.

1995-01-01

That progresses in efficiency and safety through progresses in technology and better prediction with fully benchmarked upgraded computer codes is a common goal for on the one hand the original designer of the VVER reactors and their respective fuels and on the other hand for EVF a western company resulting from a combined force with highly diversified and complementary talents in reactor and fuel design and manufacturing. It can be expected that this new challenge and dialogue between the two Russian and European industrial ventures will be mutually beneficial and yield innovative and high quality products and as a consequence strong return will be produced for the best interest of utilities operating VVER reactors. (orig./HP)

Corrosion products behaviour under VVER primary coolant conditions

International Nuclear Information System (INIS)

Grygar, T.; Zmitko, M.

2002-01-01

The aim of this work was to collect data on thermodynamic stability of Cr, Fe, and Ni oxides, mechanisms of hydrothermal corrosion of stainless steels and to compare the real observation with the theory. We found that the electrochemical potential and pH in PWR and VVER are close to the thermodynamic boundary between two fields of stable spinel type oxides. The ways of degradation of the passivating layers due to changes in water chemistry were considered and PWR and VVER systems were found to be potentially endangered by reductive attack. In certain VVER systems the characteristics of the passivating layer on steels and also concentration of soluble corrosion products seem to be in contradiction with the theoretical expectations. (author)

Isothermal and thermal-mechanical fatigue of VVER-440 reactor pressure vessel steels

Science.gov (United States)

Fekete, Balazs; Trampus, Peter

2015-09-01

The fatigue life of the structural materials 15Ch2MFA (CrMoV-alloyed ferritic steel) and 08Ch18N10T (CrNi-alloyed austenitic steel) of VVER-440 reactor pressure vessel under completely reserved total strain controlled low cycle fatigue tests were investigated. An advanced test facility was developed for GLEEBLE-3800 physical simulator which was able to perform thermomechanical fatigue experiments under in-service conditions of VVER nuclear reactors. The low cycle fatigue results were evaluated with the plastic strain based Coffin-Manson law, and plastic strain energy based model as well. It was shown that both methods are able to predict the fatigue life of reactor pressure vessel steels accurately. Interrupted fatigue tests were also carried out to investigate the kinetic of the fatigue evolution of the materials. On these samples microstructural evaluation by TEM was performed. The investigated low cycle fatigue behavior can provide reference for remaining life assessment and lifetime extension analysis.

The TACIS Nuclear Programme: Assistance in Upgrading Russian Nuclear Power Stations - An Overview of the Individual Projects in the Internet

International Nuclear Information System (INIS)

Bieth, Michel; Schoels, Hubert

2006-01-01

The European Union' TACIS1 programme has been established for the New Independent States (NIS), among them in the Russian Federation since 1991. One priority of TACIS funding is Nuclear Safety. The European Commission has made available a total of 944 Million Euros for nuclear safety programmes covering the period 1991-2003. The TACIS nuclear safety programme is devoted to the improvement of the safety of Soviet designed nuclear installations in providing technology and safety culture transfer. JRC is carrying out works in the following areas: On-Site Assistance for TACIS operating Nuclear Power Plants; Design Safety and Dissemination of TACIS results; Reactor Pressure Vessel Embrittlement for VVER; Regulatory Assistance; Industrial Waste Management; Nuclear Safeguards; All TACIS projects, dealing with these areas of activity are now available in so called Project Description Sheets (PDS) or Project Results Sheets (PRS) in the Internet for everybody. JRC has created in the Internet an easy to open and to browse database which contains the result of works in relation to the above mentioned nuclear activities. This presentation gives an on-line overview of the app. 430 projects which have been implemented so far since the outset of the TACIS Nuclear Programme in the Russian Federation, which is representative to the other CIS countries, benefiting from the TACIS. The presentation will mainly consist of an on-line-demonstration of the TACIS Nuclear WEB Page, created by JRC. (authors)

Detailed modeling of KALININ-3 NPP VVER-1000 reactor pressure vessel by the coupled system code ATHLET/BIPR-VVER

International Nuclear Information System (INIS)

Nikonov, S.P.; Velkov, K.; Pautz, A.

2011-01-01

The paper gives an overview of the recent developments of a new reactor pressure vessel (RPV) model of VVER-1000 for the coupled system code ATHLET/BIPR-VVER. Based on the previous experience a methodology is worked out for modeling the RPV in a pseudo-3D way with the help of a multiple parallel thermal-hydraulic channel scheme that follows the hexagonal fuel assembly structure from the bottom to the top of the reactor. The results of the first application of the new modeling are discussed on the base of the OECD/NEA coupled code benchmark for Kalinin-3 NPP transient. Coolant mass flow distributions in reactor volume of VVER 1000 reactor are presented and discussed. It is shown that along the core height a mass flow re-distribution of the coolant takes place starting approximately at an axial layer located 1 meter below the core outlet. (author)

Nuclear power. Volume 1. Nuclear power plant design

International Nuclear Information System (INIS)

Pedersen, E.S.

1978-01-01

NUCLEAR POWER PLANT DESIGN is intended to be used as a working reference book for management, engineers and designers, and as a graduate-level text for engineering students. The book is designed to combine theory with practical nuclear power engineering and design experience, and to give the reader an up-to-date view of the status of nuclear power and a basic understanding of how nuclear power plants function. Volume 1 contains the following chapters; (1) nuclear reactor theory; (2) nuclear reactor design; (3) types of nuclear power plants; (4) licensing requirements; (5) shielding and personnel exposure; (6) containment and structural design; (7) main steam and turbine cycles; (8) plant electrical system; (9) plant instrumentation and control systems; (10) radioactive waste disposal (waste management) and (11) conclusion

Physical startup tests for VVER-1200 of Novovoronezh NPP. Advanced technique and some results

Energy Technology Data Exchange (ETDEWEB)

Afanasiev, Dmitry A.; Kraynov, Yury A.; Pinegin, Anatoly A.; Tsyganov, Sergey V. [National Research Centre, Moscow (Russian Federation). Kurchatov Inst.

2017-09-15

The intention of the startup physics tests was to confirm design characteristics of the core loading and their compliance with safety analysis preconditions. The program of startup tests for the leading unit is usually composed in such a way that is is possible to study as much neutron-physical characteristics as possible in the safest condition of zero power. State-of-the-art safety analysis is including computer codes that use three dimensional neutron kinetics and thermohydraulics models. For the substantiation of such models, for its validation and verification there is a need in reactor experiments that implementing spatially distributed transients. We based on such statements when composing hot zero power physical startup program for the new VVER-1200 unit of Novovoronezh NPP. Several tests unconventional for VVER were developed for that program. It includes measuring the worth for each of control rod groups and measuring of single rod worth from the inserted groups - test that models rod ejection event in some sense.

Results of 15 years experiments in the PMK-2 integral-type facility for VVERs

Energy Technology Data Exchange (ETDEWEB)

Szabados, L.; Ezsoel, G.; Perneczky, L. [KFKI Atomic Energy Research Institute, Budapest (Hungary)

2001-07-01

Due to the specific features of the VVER-440/213-type reactors the transient behaviour of such a reactor system is different from the usual PWR system behaviour. To provide an experimental database for the transient behaviour of VVER systems the PMK integral-type facility, the scaled down model of the Paks NPP was designed and constructed in the early 1980's. Since the start-up of the facility 48 experiments have been performed. It was confirmed through the experiments that the facility is a suitable tool for the computer code validation experiments and to the identification of basic thermal-hydraulic phenomena occurring during plant accidents. High international interest was shown by the four Standard Problem Exercises of the IAEA and by the projects financed by the EU-PHARE. A wide range of small- and medium-size LOCA sequences have been studied to know the performance and effectiveness of ECC systems and to evaluate the thermal-hydraulic safety of the core. Extensive studies have been performed to investigate the one- and two-phase natural circulation, the effect of disturbances coming from the secondary circuit and to validate the effectiveness of accident management measures like bleed and feed. The VVER-specific case, the opening of the SG collector cover was also extensively investigated. Examples given in the report show a few results of experiments and the results of calculation analyses performed for validation purposes of codes like RELAP5, ATHLET and CATHARE. There are some other white spots in Cross Reference Matrices for VVER reactors and, therefore, further experiments are planned to perform tests primarily in further support of accident management measures at low power states of plants to facilitate the improved safety management of VVER-440-type reactors. (authors)

Results of 15 years experiments in the PMK-2 integral-type facility for VVERs

International Nuclear Information System (INIS)

Szabados, L.; Ezsoel, G.; Perneczky, L.

2001-01-01

Due to the specific features of the VVER-440/213-type reactors the transient behaviour of such a reactor system is different from the usual PWR system behaviour. To provide an experimental database for the transient behaviour of VVER systems the PMK integral-type facility, the scaled down model of the Paks NPP was designed and constructed in the early 1980's. Since the start-up of the facility 48 experiments have been performed. It was confirmed through the experiments that the facility is a suitable tool for the computer code validation experiments and to the identification of basic thermal-hydraulic phenomena occurring during plant accidents. High international interest was shown by the four Standard Problem Exercises of the IAEA and by the projects financed by the EU-PHARE. A wide range of small- and medium-size LOCA sequences have been studied to know the performance and effectiveness of ECC systems and to evaluate the thermal-hydraulic safety of the core. Extensive studies have been performed to investigate the one- and two-phase natural circulation, the effect of disturbances coming from the secondary circuit and to validate the effectiveness of accident management measures like bleed and feed. The VVER-specific case, the opening of the SG collector cover was also extensively investigated. Examples given in the report show a few results of experiments and the results of calculation analyses performed for validation purposes of codes like RELAP5, ATHLET and CATHARE. There are some other white spots in Cross Reference Matrices for VVER reactors and, therefore, further experiments are planned to perform tests primarily in further support of accident management measures at low power states of plants to facilitate the improved safety management of VVER-440-type reactors. (authors)

APROS multifunctional simulator applications for VVER-440

International Nuclear Information System (INIS)

Porkholm, K.; Kantee, H.; Tiihonen, O.

2000-01-01

Fortum Engineering Ltd and the Technical Research Centre of Finland have developed APROS simulation software since 1986. APROS is a multifunctional simulator, which is used for process and automation design, safety analysis and training simulator applications. APROS has unique features and models developed especially for VVER-440 reactors. At first the paper gives a short overview of APROS multifunctional simulator. The rest of the paper deals with different kind of applications of APROS in VVER-440 reactors' improvement and operation development. (author)

Fire protection upgrading of four Russian 440/230 VVER units

International Nuclear Information System (INIS)

Corsini, G.; Yelfimov, S.

1995-01-01

The main goal of TACIS 3.6 a project funded by the Commission of the European Communities (CEC), was the front-end engineering for upgrading the Fire Protection System (FPS) of the safety-related equipment of Novovoronezh, Units 3 and 4, and Kola, Units 1 and 2, VVER 440/230 nuclear power plants. As a first step, all the safety-related equipment had to be identified, evaluation criteria had to be established and the existing FPS reviewed against the criteria. In the second step, the selection of the upgrading measures, depending on feasibility and cost estimate, has been accomplished, room by room. The third step, carried out on schedule and completed end July 95, has been essentially the preparation of the Technical Specifications for procurement of the needed equipment including remaining detail engineering. The Russian sub-contactor Atom Energo Project (AEP), who have been the designers of these older NPP s, have done the work with the Italian Ansaldo as the consultants of their Russian colleagues. Practical aspects of the engineering work are discussed and examples of improvements selected for retrofitting described. (author)

Nuclear power. Volume 2. Nuclear power project management

International Nuclear Information System (INIS)

Pedersen, E.S.

1978-01-01

NUCLEAR POWER PLANT DESIGN is intended to be used as a working reference book for management, engineers and designers, and as a graduate-level text for engineering students. The book is designed to combine theory with practical nuclear power engineering and design experience, and to give the reader an up-to-date view of the status of nuclear power and a basic understanding of how nuclear power plants function. Volume 2 contains the following chapters: (1) review of nuclear power plants; (2) licensing procedures; (3) safety analysis; (4) project professional services; (5) quality assurance and project organization; (6) construction, scheduling, and operation; (7) nuclear fuel handling and fuel management; (8) plant cost management; and (9) conclusion

Criticality safety calculations for the nuclear waste disposal canisters

International Nuclear Information System (INIS)

Anttila, M.

1996-12-01

The criticality safety of the copper/iron canisters developed for the final disposal of the Finnish spent fuel has been studied with the MCNP4A code based on the Monte Carlo technique and with the fuel assembly burnup programs CASMO-HEX and CASMO-4. Two rather similar types of spent fuel disposal canisters have been studied. One canister type has been designed for hexagonal VVER-440 fuel assemblies used at the Loviisa nuclear power plant (IVO canister) and the other one for square BWR fuel bundles used at the Olkiluoto nuclear power plant (TVO canister). (10 refs.)

The nuclear technology development program in the U.S.S.R

International Nuclear Information System (INIS)

Lukonin, N.F.

1987-01-01

The trend of strategy on the nuclear power generation in USSR is not changed in spite of the accident in Chernobyl Nuclear Power Station. In 1986, the electric power generated by nuclear power generation was 162 billion kWh, and the heat supply by nuclear energy was 29 million Gcal. The development of nuclear power generation in USSR for 30 years proved that the atomic energy is technically omnipotent, and the economical substitution of the demand of fossil fuel with nuclear fuel is possible. As of January 1, 1987, 17 nuclear power stations were in operation in USSR, and the total power output was 31,000 MW. The share of nuclear power generation in the total electric power generation was 1/9. 11 nuclear power stations are under construction. The accelerating development of nuclear power generation is the base of meeting the electric power demand in the European region of USSR together with the power transmission from the eastern region. The nuclear power generation in USSR is based on two types of nuclear reactors, that is, water-water type VVER and water-graphite type RBMK. The accident in Chernobyl Nuclear Power Station and the situation thereafter are reported. The development of nuclear power generation in future is discussed. (Kako, I.)

Thorium fuel for light water reactors - reducing proliferation potential of nuclear power fuel cycle

Energy Technology Data Exchange (ETDEWEB)

Galperin, A; Radkowski, A [Ben-Gurion Univ. of the Negev, Beersheba (Israel)

1996-12-01

The proliferation potential of the light water reactor fuel cycle may be significantly reduced by utilization of thorium as a fertile component of the nuclear fuel. The main challenge of Th utilization is to design a core and a fuel cycle, which would be proliferation-resistant and economically feasible. This challenge is met by the Radkowsky Thorium Reactor (RTR) concept. So far the concept has been applied to a Russian design of a 1,000 MWe pressurized water reactor, known as a WWER-1000, and designated as VVERT. The following are the main results of the preliminary reference design: * The amount of Pu contained in the RTR spent fuel stockpile is reduced by 80% in comparison with a VVER of a current design. * The isotopic composition of the RTR-Pu greatly increases the probability of pre-initiation and yield degradation of a nuclear explosion. An extremely large Pu-238 content causes correspondingly large heat emission, which would complicate the design of an explosive device based on RTR-Pu. The economic incentive to reprocess and reuse the fissile component of the RTR spent fuel is decreased. The once-through cycle is economically optimal for the RTR core and cycle. To summarize all the items above: the replacement of a standard (U-based) fuel for nuclear reactors of current generation by the RTR fuel will provide an inherent barrier for nuclear weapon proliferation. This inherent barrier, in combination with existing safeguard measures and procedures is adequate to unambiguously disassociate civilian nuclear power from military nuclear power. * The RTR concept is applied to existing power plants to assure its economic feasibility. Reductions in waste disposal requirements, as well as in natural U and fabrication expenses, as compared to a standard WWER fuel, provide approximately 20% reduction in fuel cycle (authors).

Nuclear Power

International Nuclear Information System (INIS)

Douglas-Hamilton, J.; Home Robertson, J.; Beith, A.J.

1987-01-01

In this debate the Government's policy on nuclear power is discussed. Government policy is that nuclear power is the safest and cleanest way of generating electricity and is cheap. Other political parties who do not endorse a nuclear energy policy are considered not to be acting in the people's best interests. The debate ranged over the risks from nuclear power, the UK safety record, safety regulations, and the environmental effects of nuclear power. The Torness nuclear power plant was mentioned specifically. The energy policy of the opposition parties is strongly criticised. The debate lasted just over an hour and is reported verbatim. (UK)

PSB-VVER experimental and analytical investigation of station blackout accident in VVER-1000

Energy Technology Data Exchange (ETDEWEB)

Lipatov, I.A.; Kapustin, A.V.; Nikonov, S.M.; Rovnov, A.A.; Basov, A.V. [Electrogorsk Research and Engineering Centre (EREC), Moscow Region (Russian Federation); Elkin, I.V. [NSI RRC, Kurchatov Institute, Moscow (Russian Federation)

2007-07-01

In November 2003, an experiment simulating station blackout accident was carried out in the PSB-VVER integral test facility at the Electrogorsk Research and Engineering Centre (Russia). The purpose of the experiment was to provide missing data for code validation as well as to investigate the VVER thermohydraulics in the blackout conditions. The experiment covers a wide range of phenomena relating not only to transients but also to small break loss-of-coolant accidents. The data gained in the test has been used to assess the RELAP5/MOD3.3 code. In this paper, a special attention has been paid to the code assessment regarding the mixture level and entrainment in steam generator secondary side. The analysis of the recorded transient has shown that the calculation of the heat transfer on the secondary side of steam generators is very sensitive to the steam generator nodalization. (authors)

Regeneration and localization of radioactive waste in the nuclear fuel cycle

International Nuclear Information System (INIS)

Egorov, N.N.; Kudryavtsev, E.G.; Nikipelov, B.V.; Polyakov, A.S.; Zakharkin, B.S.; Mamaev, L.A.

1993-01-01

Normal functioning of the nuclear-power industry is only possible with a closed fuel cycle, including regeneration of the spent fuel from atomic power plants, the production and recycling of the secondary fuel, and localization of the radioactive waste. Despite the diversity of contemporary attitudes toward the structure of the nuclear fuel cycle around the world, the closure of the fuel cycle has been fundamental to the atomic-power industry in the USSR since the very beginning, and has taken on even greater significance in Russia today. From the beginning, the idea of a closed fuel cycle has been based essentially on one fundamental criterion: the concept of expanded productivity on the basis of fuel regeneration, i.e., the economic factor. Important as economic factors are, safety issues have taken on great significance in recent years: not only power-station reactors but all the ancillary stages of the fuel cycle must meet fundamentally new reliability, safety, and environmental hazards. The RT-1 plant is a versatile operation, regenerating spent fuel from VVER-440, BN-350, and BN-600 reactors, nuclear icebreakers and submarines, research reactors, and other power units. The plant can reprocess 400 ton/year of basic VVER-440 fuel. World-class modern processes have been introduced at the plant, meeting the necessary quality standards: zonal planning, remote operation to eliminate direct contact of the staff with radioactive material, extensive monitoring and control systems, multistage gas-purification systems, and new waste-treatment methods

YKAe - Nuclear power plant systems behaviour and operational aspects of safety

International Nuclear Information System (INIS)

Hayns, M.R.; Wolfert, K.; Sandervaag, O.

1992-12-01

The report is a mid term evaluation of the YKAe programme started in 1990. In the area safe margins of nuclear fuel and reactor core the work in support of improved performance of LWR fuel is primarily an economic matter and, therefore, should be funded directly by the utilities. As regards assessment of transient and accident situations the experiments in the PACTEL facility provide conditions for VVER reactors which are not available anywhere else. Every effort should be made to utilize this facility in further international programmes. The analysis methods developed for accident and the fire risk studies are excellent and well focused in the specific needs of the Finnish programmes. Further activities in transient and accident modelling should be coupled with the work of the APROS programme. Studies on the new technology in supervision and control of nuclear power plant processes are of special importance to Finland either for the 5th nuclear power station or for the upgrading existing systems. The work on computerized operator support systems looks to be achieving maturity and should be considered for more downstream funding. The human factors studies are of direct relevance to reactor operations. The human factors research appears sub-critical and deserves more support. Overall, the Evaluation Team felt that this small programme was well focused on Finland's needs, well integrated into the international programmes and provided good value for money. The programme direction and balance is good, and with only minor shift emphasis, should carry on its projected course

Evaluation gives the activity inventory the nuclear fuel irradiated and its radioactive waste

International Nuclear Information System (INIS)

Rodriguez Gual, Maritza

1998-01-01

The present work has as objectives to give a quantitative evaluation to the activity that possesses the nuclear fuel for 3,6% enrichment with a burnt one the 33 000 NWd/Tu proposed for the Juragua Nuclear Power Plant . In this work the method is used I calculate ORIGEN2. Obtained results are presented and they are compared with other calculations carried out in reactors type VVER-440

Calculations of 3D full-scale VVER fuel assembly and core models using MCU and BIPR-7A codes

Energy Technology Data Exchange (ETDEWEB)

Aleshin, Sergey S.; Bikeev, Artem S.; Bolshagin, Sergey N.; Kalugin, Mikhail A.; Kosourov, Evgeniy K.; Pavlovichev, Aleksandr M.; Pryanichnikov, Aleksandr V.; Sukhino-Khomenko, Evgenia A.; Shcherenko, Anna I.; Shcherenko, Anastasia I.; Shkarovskiy, Denis A. [Nuclear Research Centre ' ' Kurchatov Institute' ' , Moscow (Russian Federation)

2015-09-15

Two types of calculations were made to compare BIPR-7A and MCU results for 3D full-scale models. First EPS (emergency protection system) efficiency and in-core power distributions were analyzed for an equilibrium fuel load of VVER-1000 assuming its operation within an 18-month cycle. Computations were performed without feedbacks and with fuel burnup distributed over the core. After 3D infinite lattices of full-scale VVER-1000 fuel assemblies (A's) with uranium fuel 4.4% enrichment and uranium-erbium fuel 4.4% enrichment and Er{sub 2}O{sub 3} 1 % wt were considered. Computations were performed with feedbacks and fuel burnup at the constant power level. For different time moments effective multiplication factor and power distribution were obtained. EPS efficiency and reactivity effects at chosen time moments were analyzed.

Nuclear power plants

International Nuclear Information System (INIS)

1985-01-01

Data concerning the existing nuclear power plants in the world are presented. The data was retrieved from the SIEN (Nuclear and Energetic Information System) data bank. The information are organized in table forms as follows: nuclear plants, its status and type; installed nuclear power plants by country; nuclear power plants under construction by country; planned nuclear power plants by country; cancelled nuclear power plants by country; shut-down nuclear power plants by country. (E.G.) [pt

Primary water chemistry control at units of Paks Nuclear Power Plant

International Nuclear Information System (INIS)

Schunk, J.; Patek, G.; Pinter, T.; Tilky, P.; Doma, A.; Osz, J.

2010-01-01

The primary water chemistry of the four identical units of Paks Nuclear Power Plant has been developed based on Western-type PWR units, taking into consideration some Soviet-Russian modifications. The political changes in 90s have also influenced the water chemistry specifications and directions. At PWR units the transition operational modes have been developed while in case of VVER units - in lack of central uniform regulation - this question has become the competence and responsibility of each individual plant. This problem has resulted in separate water chemistry developments with a considerable time delay. The needs for life-time extensions all over the World have made the development of start-up and shut-down chemistry procedures extremely important, since they considerably influence the long term and safe operation of plants. The uniformly structured limit value system, the principles applied for the system development, and the logic schemes for actions to be taken are discussed in the paper, both for normal operation and transition modes. (author)

Nuclear power

International Nuclear Information System (INIS)

Porter, Arthur.

1980-01-01

This chapter of the final report of the Royal Commission on Electric Power Planning in Ontario updates its interim report on nuclear power in Ontario (1978) in the light of the Three Mile Island accident and presents the commission's general conclusions and recommendations relating to nuclear power. The risks of nuclear power, reactor safety with special reference to Three Mile Island and incidents at the Bruce generating station, the environmental effects of uranium mining and milling, waste management, nuclear power economics, uranium supplies, socio-political issues, and the regulation of nuclear power are discussed. Specific recommendations are made concerning the organization and public control of Ontario Hydro, but the commission concluded that nuclear power is acceptable in Ontario as long as satisfactory progress is made in the disposal of uranium mill tailings and spent fuel wastes. (LL)

Microstructure and embrittlement of VVER 440 reactor pressure vessel steels; Microstructure et fragilisation des aciers de cuve des reacteurs nucleaires VVER 440

Energy Technology Data Exchange (ETDEWEB)

Hennion, A

1999-03-15

27 VVER 440 pressurised water reactors operate in former Soviet Union and in Eastern Europe. The pressure vessel, is made of Cr-Mo-V steel. It contains a circumferential arc weld in front of the nuclear core. This weld undergoes a high neutron flux and contains large amounts of copper and phosphorus, elements well known for their embrittlement potency under irradiation. The embrittlement kinetic of the steel is accelerated, reducing the lifetime of the reactor. In order to get informations on the microstructure and mechanical properties of these steels, base metals, HAZ, and weld metals have been characterized. The high amount of phosphorus in weld metals promotes the reverse temper embrittlement that occurs during post-weld heat treatment. The radiation damage structure has been identified by small angle neutron scattering, atomic probe, and transmission electron microscopy. Nanometer-sized clusters of solute atoms, rich in copper with almost the same characteristics as in western pressure vessels steels, and an evolution of the size distribution of vanadium carbides, which are present on dislocation structure, are observed. These defects disappear during post-irradiation tempering. As in western steels, the embrittlement is due to both hardening and reduction of interphase cohesion. The radiation damage specificity of VVER steels arises from their high amount of phosphorus and from their significant density of fine vanadium carbides. (author)

Aspects of using a best-estimate approach for VVER safety analysis in reactivity initiated accidents

Energy Technology Data Exchange (ETDEWEB)

Ovdiienko, Iurii; Bilodid, Yevgen; Ieremenko, Maksym [State Scientific and Technical Centre on Nuclear and Radiation, Safety (SSTC N and RS), Kyiv (Ukraine); Loetsch, Thomas [TUEV SUED Industrie Service GmbH, Energie und Systeme, Muenchen (Germany)

2016-09-15

At present time, Ukraine faces the problem of small margins of acceptance criteria in connection with the implementation of a conservative approach for safety evaluations. The problem is particularly topical conducting feasibility analysis of power up-rating for Ukrainian nuclear power plants. Such situation requires the implementation of a best-estimate approach on the basis of an uncertainty analysis. For some kind of accidents, such as loss-of-coolant accident (LOCA), the best estimate approach is, more or less, developed and established. However, for reactivity initiated accident (RIA) analysis an application of best estimate method could be problematical. A regulatory document in Ukraine defines a nomenclature of neutronics calculations and so called ''generic safety parameters'' which should be used as boundary conditions for all VVER-1000 (V-320) reactors in RIA analysis. In this paper the ideas of uncertainty evaluations of generic safety parameters in RIA analysis in connection with the use of the 3D neutron kinetic code DYN3D and the GRS SUSA approach are presented.

Nuclear power

International Nuclear Information System (INIS)

Abd Khalik Wood

2005-01-01

This chapter discussed the following topics related to the nuclear power: nuclear reactions, nuclear reactors and its components - reactor fuel, fuel assembly, moderator, control system, coolants. The topics titled nuclear fuel cycle following subtopics are covered: , mining and milling, tailings, enrichment, fuel fabrication, reactor operations, radioactive waste and fuel reprocessing. Special topic on types of nuclear reactor highlighted the reactors for research, training, production, material testing and quite detail on reactors for electricity generation. Other related topics are also discussed: sustainability of nuclear power, renewable nuclear fuel, human capital, environmental friendly, emission free, impacts on global warming and air pollution, conservation and preservation, and future prospect of nuclear power

Research on loading pattern optimization for VVER reactor

International Nuclear Information System (INIS)

Tran Viet Phu; Nguyen Thi Mai Huong; Nguyen Huu Tiep; Ta Duy Long; Tran Vinh Thanh; Tran Hoai Nam

2017-01-01

A study on fuel loading pattern optimization of a VVER reactor was performed. In this study, a core physics simulator was developed based on a multi-group diffusion theory for the use in the problem of fuel loading optimization of VVER reactors. The core simulator could handle the triangular meshes of the core and the computational speed is fast. Verification of the core simulator was confirmed against a benchmark problem of a VVER-1000 reactor. Several optimization methods such as DS, SA, TS and a combination of them were investigated and implemented in coupling with the core simulator. Calculations was performed for optimizing the fuel loading pattern of the core using these methods based on a benchmark core model in comparison with the reference core. Comparison among these methods have shown that a combination of SA+TS is the most effective for the problem of fuel loading pattern optimization. Advanced methods are being researched continuously. (author)

Nuclear power

International Nuclear Information System (INIS)

Anon.

1980-01-01

The committee concludes that the nature of the proliferation problem is such that even stopping nuclear power completely could not stop proliferation completely. Countries can acquire nuclear weapons by means independent of commercial nuclear power. It is reasonable to suppose if a country is strongly motivated to acquire nuclear weapons, it will have them by 2010, or soon thereafter, no matter how nuclear power is managed in the meantime. Unilateral and international diplomatic measures to reduce the motivations that lead to proliferation should be high on the foreign policy agenda of the United States. A mimimum antiproliferation prescription for the management of nuclear power is to try to raise the political barriers against proliferation through misuse of nuclear power by strengthening the Non-Proliferation Treaty, and to seek to raise the technological barriers by placing fuel-cycle operations involving weapons-usable material under international control. Any such measures should be considered tactics to slow the spread of nuclear weapons and thus earn time for the exercise of statesmanship. The committee concludes the following about technical factors that should be considered in formulating nuclear policy: (1) rate of growth of electricity use is a primary factor; (2) growth of conventional nuclear power will be limited by producibility of domestic uranium sources; (3) greater contribution of nuclear power beyond 400 GWe past the year 2000 can only be supported by advanced reactor systems; and (4) several different breeder reactors could serve in principle as candidates for an indefinitely sustainable source of energy

Nuclear power development

International Nuclear Information System (INIS)

Nealey, S.

1990-01-01

The objective of this study is to examine factors and prospects for a resumption in growth of nuclear power in the United States over the next decade. The focus of analysis on the likelihood that current efforts in the United States to develop improved and safer nuclear power reactors will provide a sound technical basis for improved acceptance of nuclear power, and contribute to a social/political climate more conducive to a resumption of nuclear power growth. The acceptability of nuclear power and advanced reactors to five social/political sectors in the U.S. is examined. Three sectors highly relevant to the prospects for a restart of nuclear power plant construction are the financial sector involved in financing nuclear power plant construction, the federal nuclear regulatory sector, and the national political sector. For this analysis, the general public are divided into two groups: those who are knowledgeable about and involved in nuclear power issues, the involved public, and the much larger body of the general public that is relatively uninvolved in the controversy over nuclear power

Study of Fast Transient Pressure Drop in VVER-1000 Nuclear Reactor Using Acoustic Phenomenon

Directory of Open Access Journals (Sweden)

Soroush Heidari Sangestani

2018-01-01

Full Text Available This article aims to simulate the sudden and fast pressure drop of VVER-1000 reactor core coolant, regarding acoustic phenomenon. It is used to acquire a more accurate method in order to simulate the various accidents of reactor core. Neutronic equations should be solved concurrently by means of DRAGON 4 and DONJON 4 coupling codes. The results of the developed package are compared with WIMS/CITATION and final safety analysis report of Bushehr VVER-1000 reactor (FSAR. Afterwards, time dependent thermal-hydraulic equations are answered by employing Single Heated Channel by Sectionalized Compressible Fluid method. Then, the obtained results were validated by the same transient simulation in a pressurized water reactor core. Then, thermal-hydraulic and neutronic modules are coupled concurrently by use of producing group constants regarding the thermal feedback effect. Results were compared to the mentioned transient simulation in RELAP5 computer code, which show that mass flux drop is sensed at the end of channel in several milliseconds which causes heat flux drop too. The thermal feedback resulted in production of some perturbations in the changes of these parameters. The achieved results for this very fast pressure drop represent accurate calculations of thermoneutronic parameters fast changes.

Nuclear power

International Nuclear Information System (INIS)

King, P.

1990-01-01

Written from the basis of neutrality, neither for nor against nuclear power this book considers whether there are special features of nuclear power which mean that its development should be either promoted or restrained by the State. The author makes it dear that there are no easy answers to the questions raised by the intervention of nuclear power but calls for openness in the nuclear decision making process. First, the need for energy is considered; most people agree that energy is the power to progress. Then the historicalzed background to the current position of nuclear power is given. Further chapters consider the fuel cycle, environmental impacts including carbon dioxide emission and the greenhouse effect, the costs, safety and risks and waste disposal. No conclusion either for or against nuclear power is made. The various shades of opinion are outlined and the arguments presented so that readers can come to their own conclusions. (UK)

Fast Neutron Transport in the Biological Shielding Model and Other Regions of the VVER-1000 Mock-Up on the LR-0 Research Reactor

Directory of Open Access Journals (Sweden)

Košťál Michal

2016-01-01

Full Text Available A set of benchmark experiments was carried out in the full scale VVER-1000 mock-up on the reactor LR-0 in order to validate neutron transport calculation methodologies and to perform the optimization of the shape and locations of neutron flux operation monitors channels inside the shielding of the new VVER-1000 type reactors. Compared with previous experiments on the VVER-1000 mock-up on the reactor LR-0, the fast neutron spectra were measured in the extended neutron energy interval (0.1–10 MeV and new calculations were carried out with the MCNPX code using various nuclear data libraries (ENDF/B VII.0, JEFF 3.1, JENDL 3.3, JENDL 4, ROSFOND 2009, and CENDL 3.1. Measurements and calculations were carried out at different points in the mock-up. The calculation and experimental data are compared.

Strategy of nuclear power in Korea, non-nuclear-weapon state and peaceful use of nuclear power

International Nuclear Information System (INIS)

Nagasaki, Takao

2005-01-01

The nuclear power plant started at Kori in Korea in April, 1978. Korea has carried out development of nuclear power as a national policy. The present capacity of nuclear power plants takes the sixes place in the world. It supplies 42% total power generation. The present state of nuclear power plant, nuclear fuel cycle facility, strategy of domestic production of nuclear power generation, development of next generation reactor and SMART, strategy of export in corporation with industry, government and research organization, export of nuclear power generation in Japan, nuclear power improvement project with Japan, Korea and Asia, development of nuclear power system with nuclear diffusion resistance, Hybrid Power Extraction Reactor System, radioactive waste management and construction of joint management and treatment system of spent fuel in Asia are stated. (S.Y.)

Russian nuclear industry exports

International Nuclear Information System (INIS)

Gorbatchev, A.

2016-01-01

Rosatom is the world leader for the export of nuclear technologies. 34 reactors of Russian technology are being built or planned worldwide. Most reactors proposed by Rosatom are third generation VVER-1200 units with an electric power output of 1200 MWe. Although the nuclear island is always built by Rosatom, the remain of the plant can be subcontracted to other enterprises and European companies are sought because they would bring a european quality touch to Russian works. One of the main assets of Rosatom is to propose an integrated offer from supplying nuclear fuel to managing nuclear waste via the turnkey building of nuclear power plants. Another important asset is the financial assistance of the Russian state through state credit or the support from Russian national banks that appears to be a decisive advantage in the international competition to win markets. We have to temper the Russian export perspectives by noting that most projects are set in countries that are prone to instabilities and that the economic crisis affecting Russia has a negative impact on its financial means. (A.C.)

The in-core fuel management code system for VVER reactors

International Nuclear Information System (INIS)

Cada, R.; Krysl, V.; Mikolas, P.; Sustek, J.; Svarny, J.

2004-01-01

The structure and methodology of a fuel management system for NPP VVER 1000 (NPP Temelin) and VVER 440 (NPP Dukovany) is described. It is under development in SKODA JS a.s. and is followed by practical applications. The general objectives of the system are maximization of end of cycle reactivity, the minimization of fresh fuel inventory for the minimization of fed enrichment and minimization of burnable poisons (BPs) inventory. They are also safety related constraints in witch minimization of power peaking plays a dominant role. General structure of the system consists in preparation of input data for macrocode calculation, algorithms (codes) for optimization of fuel loading, calculation of fuel enrichment and BPs assignment. At present core loading can be calculated (optimized) by Tabu search algorithm (code ATHENA), genetic algorithm (code Gen1) and hybrid algorithm - simplex procedure with application of Tabu search algorithm on binary shuffling (code OPAL B ). Enrichment search is realized by the application of simplex algorithm (OPAL B code) and BPs assignment by module BPASS and simplex algorithm in OPAL B code. Calculations of the real core loadings are presented and a comparison of different optimization methods is provided. (author)

VVER-1000 small-medium break LOCAs predictions by ASTEC

International Nuclear Information System (INIS)

Georgieva, J.; Stefanova, A.; Atanasova, B.; Groudev, P.; Tusheva, P.; Mladenov, I.; Dimov, D.; Passalacqua, R.

2005-01-01

This paper deals with an assessment of ASTEC1.1v0 code in the simulation of small and medium break LOCAs (ranging from 30mm up to 70mm equivalent diameter). The reference power plant for this analysis is a VVER-1000/V320 (e.g. Units 5 and 6 at Kozloduy NPP). A preliminary comparison with MELCOR and RELAP-SCDAP severe accident codes will be discussed. This investigation has been performed in the framework of the SARNET project (under the Euratom 6 th framework program) by the FoBAUs group (Forum of Bulgarian ASTEC users). The FoBAUs group aims at the validation of the ASTEC code in the field of severe accidents. Future activities will target the ASTEC capability (as a PSA-level 2 tool) to simulate a large range of reactor accident scenarios with intervention of safety systems (either passive systems or operated by operators). The final target is to assess Severe Accident Management (SAM) procedures for VVER-1000 reactors. The ASTEC1.1v0 code version here used is the one released in June 2004 by the French IRSN (Institut de Radioprotection et de Surete Nucleaire) and the German GRS (Gesellschaft ReactorSicherheit mbH). (author)

Power generation by nuclear power plants

International Nuclear Information System (INIS)

Bacher, P.

2004-01-01

Nuclear power plays an important role in the world, European (33%) and French (75%) power generation. This article aims at presenting in a synthetic way the main reactor types with their respective advantages with respect to the objectives foreseen (power generation, resources valorization, waste management). It makes a fast review of 50 years of nuclear development, thanks to which the nuclear industry has become one of the safest and less environmentally harmful industry which allows to produce low cost electricity: 1 - simplified description of a nuclear power generation plant: nuclear reactor, heat transfer system, power generation system, interface with the power distribution grid; 2 - first historical developments of nuclear power; 3 - industrial development and experience feedback (1965-1995): water reactors (PWR, BWR, Candu), RBMK, fast neutron reactors, high temperature demonstration reactors, costs of industrial reactors; 4 - service life of nuclear power plants and replacement: technical, regulatory and economical lifetime, problems linked with the replacement; 5 - conclusion. (J.S.)

Nuclear power economic database

International Nuclear Information System (INIS)

Ding Xiaoming; Li Lin; Zhao Shiping

1996-01-01

Nuclear power economic database (NPEDB), based on ORACLE V6.0, consists of three parts, i.e., economic data base of nuclear power station, economic data base of nuclear fuel cycle and economic database of nuclear power planning and nuclear environment. Economic database of nuclear power station includes data of general economics, technique, capital cost and benefit, etc. Economic database of nuclear fuel cycle includes data of technique and nuclear fuel price. Economic database of nuclear power planning and nuclear environment includes data of energy history, forecast, energy balance, electric power and energy facilities

Economical Feedback of Increasing Fuel Enrichment on Electricity Cost for VVER-1000

Directory of Open Access Journals (Sweden)

Mohammed Saad Dwiddar

2015-08-01

Full Text Available A methodology of evaluating the economics of the front-end nuclear fuel cycle with a price change sensitivity analysis for a VVER-1000 reactor core as a case study is presented. The effect of increasing the fuel enrichment and its corresponding reactor cycle length on the energy cost is investigated. The enrichment component was found to represent the highly expenses dynamic component affecting the economics of the front-end fuel cycle. Nevertheless, the increase of the fuel enrichment will increase the reactor cycle length, which will have a positive feedback on the electricity generation cost (cent/KWh. A long reactor operation time with a cheaper energy cost set the nuclear energy as a competitive alternative when compared with other energy sources.

Modelling studies of horizontal steam generator PGV-1000 with Cathare

Energy Technology Data Exchange (ETDEWEB)

Karppinen, I. [VTT Energy, Espoo (Finland)

1995-12-31

To perform thermal-hydraulic studies applied to nuclear power plants equipped with VVER, a program of qualification and assessment of the CATHARE computer code is in progress at the Institute of Protection and Nuclear Safety (IPSN). In this paper studies of modelling horizontal steam generator of VVER-1000 with the CATHARE computer code are presented. Steady state results are compared with measured data from the fifth unit of Novovoronezh nuclear power plant. (orig.). 10 refs.

Modelling studies of horizontal steam generator PGV-1000 with Cathare

Energy Technology Data Exchange (ETDEWEB)

Karppinen, I [VTT Energy, Espoo (Finland)

1996-12-31

To perform thermal-hydraulic studies applied to nuclear power plants equipped with VVER, a program of qualification and assessment of the CATHARE computer code is in progress at the Institute of Protection and Nuclear Safety (IPSN). In this paper studies of modelling horizontal steam generator of VVER-1000 with the CATHARE computer code are presented. Steady state results are compared with measured data from the fifth unit of Novovoronezh nuclear power plant. (orig.). 10 refs.

VVER fuel cycle development at Slovakia

International Nuclear Information System (INIS)

Darilek, P.; Chrapiak, V.; Majerik, J.

1995-01-01

Four VVER-440 units are now under exploitation at Bohunice-site in Slovakia. Fuel cycle development of Unit No.3 and No.4 (type 213) is discussed and compared with equilibrium cycles in this paper. (author)

Stresses in transition region of VVER-1000 reactor vessels

International Nuclear Information System (INIS)

Namgung, I.; Nguye, T.L.

2014-01-01

Most of the western PWR reactor's bottom head is hemi-spherical shape, however for Russian designed VVER family of reactor it is ellipsoidal shape. The transition region from shell side to ellipsoidal head and transition top flange to cylindrical shell develop higher stress concentration than western PWR reactor vessel. This region can be modeled as conical shell with varying thickness. The theoretical derivation of stress in the thick-walled conical cylinder with varying thickness was developed and shown in detail. The results is applied to VVER-1000 reactor vessel of which shell to bottom ellipsoidal shell and shell to upper flange were investigated for stress field. The theoretical calculations were also compared with FEM solutions. An axisymmetric 3D model of VVER-1000 reactor vessel (without closure head) FEM model was created and internal hydrostatic pressure boundary condition was applied. The stress results from FEM and theoretical calculation were compared, and the discrepancies and accuracies of the theoretical results were discussed. (author)

Stresses in transition region of VVER-1000 reactor vessels

Energy Technology Data Exchange (ETDEWEB)

Namgung, I. [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of); Nguye, T.L. [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of); National Research Inst. of Mechanical Engineering, Hanoi City, Vietnam (China)

2014-07-01

Most of the western PWR reactor's bottom head is hemi-spherical shape, however for Russian designed VVER family of reactor it is ellipsoidal shape. The transition region from shell side to ellipsoidal head and transition top flange to cylindrical shell develop higher stress concentration than western PWR reactor vessel. This region can be modeled as conical shell with varying thickness. The theoretical derivation of stress in the thick-walled conical cylinder with varying thickness was developed and shown in detail. The results is applied to VVER-1000 reactor vessel of which shell to bottom ellipsoidal shell and shell to upper flange were investigated for stress field. The theoretical calculations were also compared with FEM solutions. An axisymmetric 3D model of VVER-1000 reactor vessel (without closure head) FEM model was created and internal hydrostatic pressure boundary condition was applied. The stress results from FEM and theoretical calculation were compared, and the discrepancies and accuracies of the theoretical results were discussed. (author)

Proposal of a benchmark for core burnup calculations for a VVER-1000 reactor core

International Nuclear Information System (INIS)

Loetsch, T.; Khalimonchuk, V.; Kuchin, A.

2009-01-01

In the framework of a project supported by the German BMU the code DYN3D should be further validated and verified. During the work a lack of a benchmark on core burnup calculations for VVER-1000 reactors was noticed. Such a benchmark is useful for validating and verifying the whole package of codes and data libraries for reactor physics calculations including fuel assembly modelling, fuel assembly data preparation, few group data parametrisation and reactor core modelling. The benchmark proposed specifies the core loading patterns of burnup cycles for a VVER-1000 reactor core as well as a set of operational data such as load follow, boron concentration in the coolant, cycle length, measured reactivity coefficients and power density distributions. The reactor core characteristics chosen for comparison and the first results obtained during the work with the reactor physics code DYN3D are presented. This work presents the continuation of efforts of the projects mentioned to estimate the accuracy of calculated characteristics of VVER-1000 reactor cores. In addition, the codes used for reactor physics calculations of safety related reactor core characteristics should be validated and verified for the cases in which they are to be used. This is significant for safety related evaluations and assessments carried out in the framework of licensing and supervision procedures in the field of reactor physics. (authors)

Nuclear power controversy

International Nuclear Information System (INIS)

Murphy, A.W.

1976-01-01

Arthur W. Murphy in the introductory chapter cites the issues, pro and con, concerning nuclear power. In assessing the present stance, he first looks back to the last American Assembly on nuclear power, held October 1957 and notes its accomplishments. He summarizes the six papers of this book, which focus on nuclear power to the end of this century. Chapter I, Safety Aspects of Nuclear Energy, by David Bodansky and Fred Schmidt, deals with the technical aspects of reactor safety as well as waste storage and plutonium diversion. Chapter 2, The Economics of Electric Power Generation--1975-2000, by R. Michael Murray, Jr., focuses specifically on coal-fired and nuclear plants. Chapter 3, How Can We Get the Nuclear Job Done, by Fritz Heimann, identifies actions that must take place to develop nuclear power in the U.S. and who should build the reprocessing plants. Chapter 4, by Arthur Murphy, Nuclear Power Plant Regulation, discusses the USNRC operation and the Price-Anderson Act specifically. Chapter 5, Nuclear Exports and Nonproliferation Strategy, by John G. Palfrey, treats the international aspects of the problem with primary emphasis upon the situation of the U.S. as an exporter of technology. Chapter 6, by George Kistiakowsky, Nuclear Power: How Much Is Too Much, expresses doubt about the nuclear effort, at least in the short run

Analysis of scenarios of the inclusion of fast reactors in the nuclear power of Russia in the context of sustainable development with the use of the INPRO methodology

International Nuclear Information System (INIS)

Usanov, V.I.; Kagramanyan, V.S.; Kalashnikov, A.G.; Korobeinikov, V.V.; Korobitsyn, V.E.; Moseyev, A.L.; Poplavskaya, E.V.

2013-01-01

Conclusions: • The two-component NES of VVER and BN reactors can meet some critical challenges of the present nuclear industry and provide a substantial contribution to enhancing sustainability of a national NP: – basically to solve up to 2050 the problem of the VVER SNF accumulation by using Pu from VVER in MOX fuel for BN reactors; – to ensure management of Pu from VVER to reduce it by 2070 to operational reserve and thus to enhance the NES proliferation resistance; – to save natural U and SWU and thus to facilitate U supply and enrichment capacities for planed deployment of VVERs in Russia and abroad. • Implementation of these opportunities might be a substance of the first phase of the NFC closure • While some INPRO indicators have shown remarkable advantages of the NES with BNs comparing to the present system, some issues in economics and NFC technologies have not got convincing answers. • These challenges along with a crucial safety issues are addressed in the Federal target programmes on transition to a CNFC with advanced FRs which are currently run in Russia

ANDREA 2.2 and 2.3. Advances in modelling of VVER cores

Energy Technology Data Exchange (ETDEWEB)

Havluj, Frantisek; Hejzlar, Jonatan; Vocka, Radim; Vysoudil, Jiri [UJV Rez, Husinec-Rez (Czech Republic)

2017-09-15

In 2016 a new version of code ANDREA for core design and reload safety analysis of VVER reactors has been released. The new code version includes several major improvements. The first of them is a seamless incorporation of short time kinetics calculations (without temperature feedback) into the code. This new feature accompanied by the possibility of excore detector signal predictions enables precise interpretation of dynamic measurements of control assembly weight during the reactor startup. Second important enhancement resides in new flexible format of cross section libraries and in new fuel temperature model based on results of TRANSURANUS fuel performance code. The new code version has been thoroughly tested and validated for both VVER440 and VVER-1000 reactors. Furthermore for the new version 2.3 which is to be released shortly we have implemented the possibility of fluent control assemblies' motion and of non-equidistant axial nodalization schemes in VVER-440 calculations.

Seismic verification methods for structures and equipment of VVER-type and RBMK-type NPPs (summary of experiences)

International Nuclear Information System (INIS)

Masopust, R.

2003-01-01

The main verification methods for structures and equipment of already existing VVER-type and RBMK-type NPPs are briefly described. The following aspects are discussed: fundamental seismic safety assessment principles for VVER/RBMK-type NPPs (seismic safety assessment procedure, typical work plan for seismic safety assessment of existing NPPs, SMA (HCLPF) calculations, modified GIP (GIP-VVER) procedure, similarity of VVER/RBMK equipment to that included in the SQUG databases and seismic interactions

Microstructure and embrittlement of VVER 440 reactor pressure vessel steels

International Nuclear Information System (INIS)

Hennion, A.

1999-03-01

27 VVER 440 pressurised water reactors operate in former Soviet Union and in Eastern Europe. The pressure vessel, is made of Cr-Mo-V steel. It contains a circumferential arc weld in front of the nuclear core. This weld undergoes a high neutron flux and contains large amounts of copper and phosphorus, elements well known for their embrittlement potency under irradiation. The embrittlement kinetic of the steel is accelerated, reducing the lifetime of the reactor. In order to get informations on the microstructure and mechanical properties of these steels, base metals, HAZ, and weld metals have been characterized. The high amount of phosphorus in weld metals promotes the reverse temper embrittlement that occurs during post-weld heat treatment. The radiation damage structure has been identified by small angle neutron scattering, atomic probe, and transmission electron microscopy. Nanometer-sized clusters of solute atoms, rich in copper with almost the same characteristics as in western pressure vessels steels, and an evolution of the size distribution of vanadium carbides, which are present on dislocation structure, are observed. These defects disappear during post-irradiation tempering. As in western steels, the embrittlement is due to both hardening and reduction of interphase cohesion. The radiation damage specificity of VVER steels arises from their high amount of phosphorus and from their significant density of fine vanadium carbides. (author)

Financing nuclear power

International Nuclear Information System (INIS)

Sheriffah Noor Khamseah Al-Idid Syed Ahmad Idid

2009-01-01

Global energy security and climate change concerns sparked by escalating oil prices, high population growth and the rapid pace of industrialization are fueling the current interest and investments in nuclear power. Globally, a significant number policy makers and energy industry leaders have identified nuclear power as a favorable alternative energy option, and are presently evaluating either a new or an expanded role for nuclear power. The International Atomic Energy Agency (IAEA) has reported that as of October 2008, 14 countries have plans to construct 38 new nuclear reactors and about 100 more nuclear power plants have been written into the development plans of governments for the next three decades. Hence as new build is expected to escalate, issues of financing will become increasingly significant. Energy supply, including nuclear power, considered as a premium by government from the socio-economic and strategic perspective has traditionally been a sector financed and owned by the government. In the case for nuclear power, the conventional methods of financing include financing by the government or energy entity (utility or oil company) providing part of the funds from its own resources with support from the government. As national financing is, as in many cases, insufficient to fully finance the nuclear power plants, additional financing is sourced from international sources of financing including, amongst others, Export Credit Agencies (ECAs) and Multilateral Development Institutions. However, arising from the changing dynamics of economics, financing and business model as well as increasing concerns regarding environmental degradation , transformations in methods of financing this energy sector has been observed. This paper aims to briefly present on financing aspects of nuclear power as well as offer some examples of the changing dynamics of financing nuclear power which is reflected by the evolution of ownership and management of nuclear power plants

Nuclear power debate

International Nuclear Information System (INIS)

Hunwick, Richard

2005-01-01

A recent resurgence of interest in Australia in the nuclear power option has been largely attributed to growing concerns over climate change. But what are the real pros and cons of nuclear power? Have advances in technology solved the sector's key challenges? Do the economics stack up for Australia where there is so much coal, gas and renewable resources? Is the greenhouse footprint' of nuclear power low enough to justify its use? During May and June, the AIE hosted a series of Branch events on nuclear power across Sydney, Adelaide and Perth. In the interest of balance, and at risk of being a little bit repetitive, here we draw together four items that resulted from these events and that reflect the opposing views on nuclear power in Australia. Nuclear Power for Australia: Irrelevant or Inevitable? - a summary of the presentations to the symposium held by Sydney Branch on 8 June 2005. Nuclear Reactors Waste the Planet - text from the flyer distributed by The Greens at their protest gathering outside the symposium venue on 8 June 2005. The Case For Nuclear Power - an edited transcript of Ian Hore-Lacy's presentation to Adelaide Branch on 19 May 2005 and to Perth Branch on 28 June 2005. The Case Against Nuclear Power - an article submitted to Energy News by Robin Chappie subsequent to Mr Hore-Lacy's presentation to Perth Branch

CFD Analysis of a Slug Mixing Experiment Conducted on a VVER-1000 Model

Directory of Open Access Journals (Sweden)

F. Moretti

2009-01-01

Full Text Available A commercial CFD code was applied, for validation purposes, to the simulation of a slug mixing experiment carried out at OKB “Gidropress” scaled facility in the framework of EC TACIS project R2.02/02: “Development of safety analysis capabilities for VVER-1000 transients involving spatial variations of coolant properties (temperature or boron concentration at core inlet.” Such experimental model reproduces a VVER-1000 nuclear reactor and is aimed at investigating the in-vessel mixing phenomena. The addressed experiment involves the start-up of one of the four reactor coolant pumps (the other three remaining idle, and the presence of a tracer slug on the starting loop, which is thus transported to the reactor pressure vessel where it mixes with the clear water. Such conditions may occur in a boron dilution scenario, hence the relevance of the addressed phenomena for nuclear reactor safety. Both a pretest and a posttest CFD simulations of the mentioned experiment were performed, which differ in the definition of the boundary conditions (based either on nominal quantities or on measured quantities, resp.. The numerical results are qualitatively and quantitatively analyzed and compared against the measured data in terms of space and time tracer distribution at the core inlet. The improvement of the results due to the optimization of the boundary conditions is evidenced, and a quantification of the simulation accuracy is proposed.

Nuclear power prospects

Energy Technology Data Exchange (ETDEWEB)

NONE

1960-09-15

A survey of the nuclear power needs of the less-developed countries and a study of the technology and economics of small and medium scale power reactors are envisioned by the General Conference. Agency makes its services available to Member States to assist them for their future nuclear power plans, and in particular in studying the technical and economic aspects of their power programs. The Agency also undertakes general studies on the economics of nuclear power, including the collection and analysis of cost data, in order to assist Member States in comparing and forecasting nuclear power costs in relation to their specific situations

Simulation of mixing effects in a VVER-1000 reactor

International Nuclear Information System (INIS)

Ulrich Bieder; Gauthier Fauchet; Sylvie Betin; Nikola Kolev; Dimitar Popov

2005-01-01

Full text of publication follows: The work presented has been performed in the framework of the OECD/NEA thermalhydraulic benchmark V1000CT-2. This benchmark is related to fluid mixing in the reactor vessel during a MSLB accident scenario in a VVER-1000 reactor. The purpose of the first exercise is to test the capability of CFD codes to represent the coolant mixing in the reactor vessel, in particular in the downcomer and the lower plenum. Coolant mixing in a VVER-1000 V320 reactor was investigated in plant experiments during the commissioning of Kozloduy Unit 5 and 6. Starting from nearly symmetric states, asymmetric loop operation in different combinations was caused by disturbing the steam flow from one or more steam generators. Non-uniform and asymmetric loop flow mixing in the reactor vessel has been observed in the event of asymmetric loop operation. For certain flow patterns there is a shift (swirl) of the main loop flows with respect to the cold leg axes. This azimuthal shift as well as mixing coefficients from cold legs to the fuel assembly inlets have been measured. The presented reference problem is a pure TH problem with given boundary conditions and power distributions. During a stabilization phase, the thermal power of the reactor was 281 MW i.e. 9.36% of the nominal power according to primary balance. Then, a transient was initiated by closing the steam isolation valve of the steam generator one (SG-1) and isolating SG-1 from feed water. The coolant temperature in the cold and hot legs of Loop no 1 rose by 13-13.5 C. After about 20 minutes a stabilized state was reached which is considered as 'final state'. This final state has been analysed with the Trio-U code. Trio-U is a CFD code developed by the CEA Grenoble, aimed to supply an efficient computational tool to simulate transient thermalhydraulic mono-phase turbulent flows encountered in nuclear systems as well as in industrial processes. For the presented study, a LES approach was used. Therefore

Assessment of the recovery annealing efficiency for VVER-1000 materials' structure reset and lifetime extension

International Nuclear Information System (INIS)

Gurovich, B.; Kuleshova, E.; Prikhodko, K.; Fedotova, S.

2011-01-01

The results of the VVER-1000 reactor pressure vessels welds studies based on the surveillance specimens sets have revealed a high embrittlement rate of steel with high nickel content compared with predicted embrittlement determined from the Russian Guide. For these critical vessels further safe operation (even during design service life) is not allowed without additional measures (recovery annealing of the VVER-1000 welds as earlier for VVER- 440). The reason is that the rate of high nickel VVER-1000 welds embrittlement is significantly higher than that is for base metal. In order to solve a problem of VVER-1000 lifetime extension recovery annealing validation and accelerated reirradiation of specimens for prolonged operation period estimation after annealing were necessary. In this work comparison of electron-microscopy fine structure studies and fractographic studies of Charpy specimens fracture surface of the VVER-1000 high nickel welds in different states were carried out. It allows estimation of the recovery annealing effect on steels structure and its behavior at further operation. It is shown that both secondary and primary irradiation causes alike radiation-induced fine structure changes: dislocation loops and nano-size precipitates. Recovery annealing leads to full dislocation loops dissolution and significant nano-size precipitates solution but not to the initial values. The rate of radiation defects and radiation-induced precipitates accumulation at reirradiation weld after recovery annealing is lower than at primary irradiation and determine the lower secondary embrittlement rate of VVER-1000 weld. (authors)

OECD/DOE/CEA VVER-1000 Coolant Transient Benchmark. Summary Record of the First Workshop (V1000-CT1)

International Nuclear Information System (INIS)

2003-01-01

The first workshop for the VVER-1000 Coolant Transient Benchmark TT Benchmark was hosted by the Commissariat a l'Energie Atomique, Centre d'Etudes de Saclay, France. The V1000CT benchmark defines standard problems for validation of coupled three-dimensional (3-D) neutron-kinetics/system thermal-hydraulics codes for application to Soviet-designed VVER-1000 reactors using actual plant data without any scaling. The overall objective is to access computer codes used in the safety analysis of VVER power plants, specifically for their use in reactivity transient simulations in a VVER-1000. The V1000CT benchmark consists of two phases: V1000CT-1 - simulation of the switching on of one main coolant pump (MCP) while the other three MCP are in operation, and V1000CT- 2 - calculation of coolant mixing tests and Main Steam Line Break (MSLB) scenario. Further background information on this benchmark can be found at the OECD/NEA benchmark web site . The purpose of the first workshop was to review the benchmark activities after the Starter Meeting held last year in Dresden, Germany: to discuss the participants' feedback and modifications introduced in the Benchmark Specifications on Phase 1; to present and to discuss modelling issues and preliminary results from the three exercises of Phase 1; to discuss the modelling issues of Exercise 1 of Phase 2; and to define work plan and schedule in order to complete the two phases

SCORPIO-VVER core monitoring and surveillance system with advanced capabilities

International Nuclear Information System (INIS)

Molnar, Jozef; Vocka, Radim

2010-01-01

The SCORPIO (SCORPIO-VVER) core monitoring system, its basic features and history of implementation at Czech NPPs are described. The most important improvements in the area of neutron physics, core thermal analysis and operation support are as follows: Moving to the 42 axial nodes across the whole system (2004); Implementation of new cross section library to support mixed reactor core with differences in axial geometry of used fuel types and enhancement of Core Simulator boundary conditions model, to properly address the 'wild' geometry in axial direction; Adjusting the thermohydraulic and neutron-physical models regarding to the Gd2 fuel needs; Support up to 5 types of FAs and 2 types of SPND (Posit, IST); Extension of form functions for pin-wise reconstruction to improve pin-power prediction in control rod coupler region; System adaptation to the new upgraded digital I and C unit system; Integration of the SCORPIO-VVER system and its workstation into the plant redundant in-core system; Implementation of new On-Line form function generation to module RECON; New design of the Strategy Generator with advanced predictions; Adaptation of the system to support the new up-rated reactor thermal power; Adding new online SDM calculation function into to system; Implementation of the new 3D power reconstruction with SPND interpretation; Extending the limit checking to the 'full core' checking. The control of margins to the technical specification: Extended to full core - all FA is controlled individually in core; The limits are definable up to 59 FA (1/6 symmetry); 4 limited parameters are controlled - Kr, qlin, Tout-fa, dTfa; 2 additional parameters are monitored - dTsat, DNBR; New MMI are developed to present the limited and controlled parameters in core. Upgrade 3 is planned for the Slovak Bohunice NPP in 2011-2012. (P.A.)

Nuclear power in Asia

Energy Technology Data Exchange (ETDEWEB)

Hagen, Ronald E.

1998-08-01

Contains Executive Summary and Chapters on: Nuclear Energy in the Asian context; Types of nuclear power reactors used in Asia; A survey of nuclear power by country; The economics of nuclear power; Fuels, fuel cycles and reprocessing; Environmental issues and waste disposal; The weapons issues and nuclear power; Conclusions. (Author)

Nuclear power

International Nuclear Information System (INIS)

Bupp, I.C.

1991-01-01

Is a nuclear power renaissance likely to occur in the United States? This paper investigates the many driving forces that will determine the answer to that question. This analysis reveals some frequently overlooked truths about the current state of nuclear technology: An examination of the issues also produces some noteworthy insights concerning government regulations and related technologies. Public opinion will play a major role in the unfolding story of the nuclear power renaissance. Some observers are betting that psychological, sociological, and political considerations will hod sway over public attitudes. Others wager that economic and technical concerns will prevail. The implications for the nuclear power renaissance are striking

Nuclear power in perspective

International Nuclear Information System (INIS)

Addinall, E.; Ellington, H.

1982-01-01

The subject is covered in chapters: (the nature of nuclear power) the atomic nucleus - a potential source of energy; how nuclear reactors work; the nuclear fuel cycle; radioactivity - its nature and biological effects; (why we need nuclear power) use of energy in the non-communist world -the changing pattern since 1950; use of energy - possible future scenarios; how our future energy needs might be met; (a possible long term nuclear strategy) the history of nuclear power; a possible nuclear power strategy for the Western World; (social and environmental considerations) the hazards to workers in the nuclear power industry; the hazards to the general public (nuclear power industry; reactor operation; transport of radioactive materials; fuel reprocessing; radioactive waste disposal; genetic hazards); the threat to democratic freedom and world peace. (U.K.)

Assessment of environmental public exposure from a hypothetical nuclear accident for Unit-1 Bushehr nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Sohrabi, M.; Ghasemi, M.; Amrollahi, R.; Khamooshi, C.; Parsouzi, Z. [Amirkabir University of Technology, Health Physics and Dosimetry Research Laboratory, Department of Physics, Tehran (Iran, Islamic Republic of)

2013-05-15

Unit-1 of the Bushehr nuclear power plant (BNPP-1) is a VVER-type reactor with 1,000-MWe power constructed near Bushehr city at the coast of the Persian Gulf, Iran. The reactor has been recently operational to near its full power. The radiological impact of nuclear power plant (NPP) accidents is of public concern, and the assessment of radiological consequences of any hypothetical nuclear accident on public exposure is vital. The hypothetical accident scenario considered in this paper is a design-basis accident, that is, a primary coolant leakage to the secondary circuit. This scenario was selected in order to compare and verify the results obtained in the present paper with those reported in the Final Safety Analysis Report (FSAR 2007) of the BNPP-1 and to develop a well-proven methodology that can be used to study other and more severe hypothetical accident scenarios for this reactor. In the present study, the version 2.01 of the PC COSYMA code was applied. In the early phase of the accidental releases, effective doses (from external and internal exposures) as well as individual and collective doses (due to the late phase of accidental releases) were evaluated. The surrounding area of the BNPP-1 within a radius of 80 km was subdivided into seven concentric rings and 16 sectors, and distribution of population and agricultural products was calculated for this grid. The results show that during the first year following the modeled hypothetical accident, the effective doses do not exceed the limit of 5 mSv, for the considered distances from the BNPP-1. The results obtained in this study are in good agreement with those in the FSAR-2007 report. The agreement obtained is in light of many inherent uncertainties and variables existing in the two modeling procedures applied and proves that the methodology applied here can also be used to model other severe hypothetical accident scenarios of the BNPP-1 such as a small and large break in the reactor coolant system as well

Optimization in the scale of nuclear power generation and the economy of nuclear power

International Nuclear Information System (INIS)

Suzuki, Toshiharu

1983-01-01

In the not too distant future, the economy of nuclear power will have to be restudied. Various conditions and circumstances supporting this economy of nuclear power tend to change, such as the decrease in power demand and supply, the diversification in base load supply sources, etc. The fragility in the economic advantage of nuclear power may thus be revealed. In the above connection, on the basis of the future outlook of the scale of nuclear power generation, that is, the further reduction of the current nuclear power program, and of the corresponding supply and demand of nuclear fuel cycle quantities, the aspect of the economic advantage of nuclear power was examined, for the purpose of optimizing the future scale of nuclear power generation (the downward revision of the scale, the establishment of the schedule of nuclear fuel cycle the stagnation of power demand and nuclear power generation costs). (Mori, K.)

Restart of the Armenia-2 Nuclear Power Station: Radiological emergency preparedness considerations for the nearby American community

International Nuclear Information System (INIS)

Vargo, G.J.; Sherwood, G.L.

1996-01-01

The Armenia Nuclear Power Station is located at Metsamor, approximately 30 km NW of the capital, Yerevan. The station, a two-unit, first-generation Soviet-designed VVER-440/270 pressurized water reactor plant was closed following the 1988 earthquake near Spitak. Because of a severe energy shortage the Government of Armenia has undertaken a program to recommission Unit 2. The plant design and circumstances surrounding its closure caused members of the U.S. Embassy staff and the American community in Armenia to express concerns for their safety in the event of a radiological emergency. In response, two representatives from the U.S. Department of Energy's International Nuclear Safety Program traveled to Armenia to review the Status of radiological emergency preparedness, meet with the American community, and make protective action recommendations. In this presentation we examine the major issues associated with recommissioning of Armenia-2, the challenges involved with developing a radiological emergency preparedness program for the American community, and our recommendations for protective actions in the absence of a strong communications and radiological monitoring infrastructure

Nuclear power

International Nuclear Information System (INIS)

Abd Khalik Wood

2003-01-01

This chapter discuss on nuclear power and its advantages. The concept of nucleus fission, fusion, electric generation are discussed in this chapter. Nuclear power has big potential to become alternative energy to substitute current conventional energy from coal, oil and gas

Erosion-corrosion entrainment of iron-containing compounds as a source of deposits in steam generators used at nuclear power plants equipped with VVER reactors

Science.gov (United States)

Tomarov, G. V.; Shipkov, A. A.

2011-03-01

The main stages and processes through which deposits are generated, migrate, and precipitate in the metal-secondary coolant system of power units at nuclear power plants are analyzed and determined. It is shown that substances produced by the mechanism of general erosion-corrosion are the main source of the ionic-colloid form of iron, which is the main component of deposits in a steam generator. Ways for controlling the formation of deposits in a nuclear power plant's steam generator are proposed together with methods for estimating their efficiency.

Energy Balance of Nuclear Power Generation. Life Cycle Analyses of Nuclear Power

International Nuclear Information System (INIS)

Wallner, A.; Wenisch, A.; Baumann, M.; Renner, S.

2011-01-01

The accident at the Japanese nuclear power plant Fukushima in March 2011 triggered a debate about phasing out nuclear energy and the safety of nuclear power plants. Several states are preparing to end nuclear power generation. At the same time the operational life time of many nuclear power plants is reaching its end. Governments and utilities now need to take a decision to replace old nuclear power plants or to use other energy sources. In particular the requirement of reducing greenhouse gas emissions (GHG) is used as an argument for a higher share of nuclear energy. To assess the contribution of nuclear power to climate protection, the complete life cycle needs to be taken into account. Some process steps are connected to high CO2 emissions due to the energy used. While the processes before and after conventional fossil-fuel power stations can contribute up to 25% of direct GHG emission, it is up to 90 % for nuclear power (Weisser 2007). This report aims to produce information about the energy balance of nuclear energy production during its life cycle. The following key issues were examined: How will the forecasted decreasing uranium ore grades influence energy intensity and greenhouse emissions and from which ore grade on will no energy be gained anymore? In which range can nuclear energy deliver excess energy and how high are greenhouse gas emissions? Which factors including ore grade have the strongest impact on excess energy? (author)

Nuclear power and nuclear safety 2008

International Nuclear Information System (INIS)

Lauritzen, B.; Oelgaard, P.L.; Kampmann, D.

2009-06-01

The report is the fifth report in a series of annual reports on the international development of nuclear power production, with special emphasis on safety issues and nuclear emergency preparedness. The report is written in collaboration between Risoe DTU and the Danish Emergency Management Agency. The report for 2008 covers the following topics: status of nuclear power production, regional trends, reactor development, safety related events of nuclear power, and international relations and conflicts. (LN)

Catalytic oxidative pyrolysis of spent organic ion exchange resins from nuclear power plants

International Nuclear Information System (INIS)

Sathi Sasidharan, N.; Deshingkar, D.S.; Wattal, P.K.; Shirsat, A.N.; Bharadwaj, S.R.

2005-08-01

The spent IX resins from nuclear power reactors are highly active solid wastes generated during operations of nuclear reactors. Catalytic oxidative pyrolysis of these resins can lead to high volume reduction of these wastes. Low temperature pyrolysis of transition metal ion loaded IX resins in presence of nitrogen was carried out in order to optimize catalyst composition to achieve maximum weight reduction. Thermo gravimetric analysis of the pyrolysis residues was carried out in presence of air in order to compare the oxidative characteristics of transition metal oxide catalysts. Copper along with iron, chromium and nickel present in the spent IX resins gave the most efficient catalyst combination for catalytic and oxidative pyrolysis of the residues. During low temperature catalytic pyrolysis, 137 Cesium volatility was estimated to be around 0.01% from cationic resins and around 0.1% from anionic resins. During oxidative pyrolysis at 700 degC, nearly 10 to 40% of 137 Cesium was found to be released to off gases depending upon type of resin and catalyst loaded on to it. The oxidation of pyrolytic residues at 700 degC gave weight reduction of 15% for cationic resins and 93% for anionic resins. Catalytic oxidative pyrolysis is attractive for reducing weight and volume of spent cationic resins from PHWRs and VVERs. (author)

Power program and nuclear power

International Nuclear Information System (INIS)

Chernilin, Yu.F.

1990-01-01

Main points of the USSR power program and the role of nuclear power in fuel and power complex of the country are considered. Data on dynamics of economic indices of electric power generation at nuclear power plants during 1980-1988 and forecasts till 2000 are presented. It is shown that real cost of 1 kW/h of electric power is equal to 1.3-1.8 cop., and total reduced cost is equal to 1.8-2.4 cop

Department of Energy's team's analyses of Soviet designed VVERs (water-cooled water-moderated atomic energy reactors)

Energy Technology Data Exchange (ETDEWEB)

1989-09-01

This document contains apprendices A through P of this report. Topics discussed are: a cronyms and technical terms, accident analyses reactivity control; Soviet safety regulations; radionuclide inventory; decay heat; operations and maintenance; steam supply system; concrete and concrete structures; seismicity; site information; neutronic parameters; loss of electric power; diesel generator reliability; Soviet codes and standards; and comparisons of PWR and VVER features. (FI)

Structural mechanisms of the flux effect for VVER-1000 reactor pressure vessel materials

International Nuclear Information System (INIS)

Gurovich, B.; Kuleshova, E.; Fedotova, S.; Maltsev, D.; Zabusov, O.; Frolov, A.; Erak, D.; Zhurko, D.

2015-01-01

To justify the lifetime extension of VVER-1000 reactor pressure vessels (RPV) up to 60 years and more it is necessary to expand the existing surveillance samples database to beyond design fluence by means of accelerated irradiation in a research reactor. Herewith since the changes in mechanical properties of materials under irradiation are due to occurring structural changes, correct analysis of the data obtained at accelerated irradiation of VVER-1000 RPV materials requires a clear understanding of the structural mechanisms that are responsible for the flux effect in VVER-1000 RPV steels. Two mechanisms are responsible for radiation embrittlement of VVER-1000 RPV steels: the hardening one (radiation hardening due to formation of radiation-induced Ni-based precipitates and radiation defects) and non-hardening one (due to formation of impurities segregations at grain boundaries - reversible temper brittleness). In this context for an adequate interpretation of the mechanical tests results when justifying the lifetime extension of existing units a complex of comparative structural studies (TEM, SEM and AES) of VVER-1000 RPV materials irradiated in different conditions (in research reactor IR-8 and within surveillance samples) was performed. It is shown that the flux effect is observed for materials with high nickel content (weld metals with Ni content > 1.35%) and it is mostly due to the contribution of non-hardening mechanism of radiation embrittlement (the difference in the accumulation kinetics of grain boundary phosphorus segregation) and somewhat contribution of the hardening mechanism (the difference in density of radiation-induced precipitates). Therefore when analyzing the results obtained from the accelerated irradiation of VVER-1000 WM the correction for the flux effect should be made. (authors)

Nuclear power revisited

International Nuclear Information System (INIS)

Grear, B.

2008-01-01

Modern development of nuclear power technology and the established framework of international agreements and conventions are responding to the major political, economic and environmental issues - high capital costs, the risks posed by nuclear wastes and accidents, and the proliferation of nuclear weaponry - that until recently hindered the expansion of nuclear power.

The use of the acoustic emission for the components of the primary circuit of the nuclear power plants

International Nuclear Information System (INIS)

Svoboda, V.

1992-01-01

Full text: The Modrany Engineering Works (Modranske strojirny) is a producer and a final supplier of the main connecting piping circuit systems and valves for the nuclear power plants (type VVER 440 and VVER 1000) built in Czechoslovakia. Besides the delivery and assembly of valves and components methods there were developed for a monitoring of the stated equipment ability of a service in the Material and Diagnostic Laboratory, which is a part of the company. An important object of this work is to obtain a sufficient set of data and to work out suitable methods, on the basis of which it would be possible to perform a serious estimation of residual service life of the main piping components after certain service operation of the nuclear power plant. During the operation of a nuclear power station a failure of the main piping circuit could happen in either of two possible modes: 1.) A sudden break - by an unstable defect propagation leading to a. final fracture of the piping; 2) A fatigue failure - which is characterised by a gradual subcritical growth of defect in relation to the loading parameters. This process is frequently accelerated by further processes, e.g. corrosion. It is therefore suitable to use such physical and mechanical quantities, which characterize the material damage. Acoustic emission signals belongs to these quantities. A knowledge of the response of these signals in relation to the damage of the material gives us the possibility to evaluate the residual life of the piping containing defects. The importance of this is increasing mainly after a long period of service. She paper deals in details with experience gained in application of acoustic emission, during pressure tests of primary circuit components (elbow, welds, T- junction etc) in laboratory conditions which imitate those in service. There are shown some results of cyclic fatigue tests by internal pressure on prototypes models and specimen. Acoustic emission method represents the

Research activities at nuclear research institute in water chemistry and corrosion

International Nuclear Information System (INIS)

Kysela, Jan

2000-01-01

Research activities at Nuclear Research Institute Rez (NRI) are presented. They are based on former heavy water reactor program and now on pressurized reactors VVER types which are operated on Czech republic. There is LVR-15 research reactor operated in NRI. The reactor and its experimental facilities is utilized for water chemistry and corrosion studies. NRI services for power plants involve water chemistry optimalization, radioactivity build-up, fuel corrosion and structural materials corrosion tests. (author)

600 MW nuclear power database

International Nuclear Information System (INIS)

Cao Ruiding; Chen Guorong; Chen Xianfeng; Zhang Yishu

1996-01-01

600 MW Nuclear power database, based on ORACLE 6.0, consists of three parts, i.e. nuclear power plant database, nuclear power position database and nuclear power equipment database. In the database, there are a great deal of technique data and picture of nuclear power, provided by engineering designing units and individual. The database can give help to the designers of nuclear power

Nuclear power and nuclear safety 2006

International Nuclear Information System (INIS)

Lauritzen, B.; Oelgaard, P.L.; Kampmann, D.; Majborn, B.; Nonboel, E.; Nystrup, P.E.

2007-04-01

The report is the fourth report in a series of annual reports on the international development of nuclear power production, with special emphasis on safety issues and nuclear emergency preparedness. The report is written in collaboration between Risoe National Laboratory and the Danish Emergency Management Agency. The report for 2006 covers the following topics: status of nuclear power production, regional trends, reactor development and development of emergency management systems, safety related events of nuclear power, and international relations and conflicts. (LN)

Nuclear power and nuclear safety 2004

International Nuclear Information System (INIS)

2005-03-01

The report is the second report in a new series of annual reports on the international development of nuclear power production, with special emphasis on safety issues and nuclear emergency preparedness. The report is written in collaboration between Risoe National Laboratory and the Danish Emergency Management Agency. The report for 2004 covers the following topics: status of nuclear power production, regional trends, reactor development and development of emergency management systems, safety related events of nuclear power and international relations and conflicts. (ln)

Nuclear power and nuclear safety 2005

International Nuclear Information System (INIS)

Lauritzen, B.; Oelgaard, P.L.; Kampman, D.; Majborn, B.; Nonboel, E.; Nystrup, P.E.

2006-03-01

The report is the third report in a series of annual reports on the international development of nuclear power production, with special emphasis on safety issues and nuclear emergency preparedness. The report is written in collaboration between Risoe National Laboratory and the Danish Emergency Management Agency. The report for 2005 covers the following topics: status of nuclear power production, regional trends, reactor development and development of emergency management systems, safety related events of nuclear power and international relations and conflicts. (ln)

The Korean nuclear power program

International Nuclear Information System (INIS)

Choi, Chang Tong

1996-01-01

Although the world nuclear power industry may appear to be in decline, continued nuclear power demand in Korea indicates future opportunities for growth and prosperity in this country. Korea has one of the world's most vigorous nuclear power programs. Korea has been an active promoter of nuclear power generation since 1978, when the country introduced nuclear power as a source of electricity. Korea now takes pride in the outstanding performance of its nuclear power plants, and has established a grand nuclear power scheme. This paper is aimed at introducing the nuclear power program of Korea, including technological development, international cooperation, and CANDU status in Korea. (author). 2 tabs

Tightening unit EZ 250 for VVER 1000 type reactor pressure vessel head flange joints

International Nuclear Information System (INIS)

Ruchar, Miloslav; Nadenik, Tomas; Kroj, Ludek

2010-01-01

The programme of flange joints tightening by seals made of expanded graphite for VVER 440 and VVER 1000 reactor head flange joints is highlighted, and tightening units of row EZ 650 and EZ 650 TK and KNI for VVER 440 reactor head flange joints and EZ 250 tightening unit for VVER 1000 reactor head flange joints are described in detail. The main advantages of electronically controlled tightening units include: Precise and uniform compression of the gasket during the tightening procedure; Automated solution to the graphite relaxing problem during tightening; Possibility of diagnosis of the thread status of the joints being tightened; Alleviation of operator's tough work; Shorter time of tensioning associated with a lower collective doses; Quick preparation of tightening procedure report from the data measured; Calibration renewal is possible in advance at time of unit storage without the need to place it on a real joint. (P.A.)

Dosimetry of VVER-1000 Reactor Pressure Vessel and Surveillance Specimens as a part of PLiM at Ukrainian NPPs

International Nuclear Information System (INIS)

Bukanov, V.N.; Diemokhin, V.L.; Grytsenko, O.V.; Ilkovych, V.V.; Pugach, A.M.; Pugach, S.M.; Vasylieva, O.G.; Vyshnevskyi, I.M.; Kasatkin, O.G.

2012-01-01

A regular surveillance program for VVER-1000 and its shortages are described. The Methodology for determination of neutron flux functionals on surveillance specimens of VVER-1000 pressure vessel is presented. The radiation exposure monitoring system for VVER-1000 pressure vessel is described. The main principles of an additional surveillance program for VVER-1000 are presented. The Dosimetry Experiment, which is already carrying out at Unit 3 of Rivne NPP, is described. (author)

The politics of nuclear power

International Nuclear Information System (INIS)

Elliott, D.

1978-01-01

The contents of the book are: introduction; (part 1, the economy of nuclear power) nuclear power and the growth of state corporatism, ownership and control - the power of the multi-nationals, economic and political goals - profit or control, trade union policy and nuclear power; (part 2, nuclear power and employment) nuclear power and workers' health and safety, employment and trade union rights, jobs, energy and industrial strategy, the alternative energy option; (part 3, political strategies) the anti-nuclear movement, trade unions and nuclear power; further reading; UK organisations. (U.K.)

The reality of nuclear power

International Nuclear Information System (INIS)

Murphy, D.

1979-01-01

The following matters are discussed in relation to the nuclear power programmes in USA and elsewhere: siting of nuclear power plants in relation to a major geological fault; public attitudes to nuclear power; plutonium, radioactive wastes and transfrontier contamination; radiation and other hazards; economics of nuclear power; uranium supply; fast breeder reactors; insurance of nuclear facilities; diversion of nuclear materials and weapons proliferation; possibility of manufacture of nuclear weapons by developing countries; possibility of accidents on nuclear power plants in developing countries; radiation hazards from use of uranium ore tailings; sociological alternative to use of nuclear power. (U.K.)

Natural circulation in a VVER reactor geometry: Experiments with the PACTEL facility and Cathare simulations

Energy Technology Data Exchange (ETDEWEB)

Raussi, P.; Kainulainen, S. [Lappeenranta Univ. of Technology, Lappeenranta (Finland); Kouhia, J. [VTT Energy, Lappeenranta (Finland)

1995-09-01

There are some 40 reactors based on the VVER design in use. Database available for computer code assessment for VVER reactors is rather limited. Experiments were conducted to study natural circulation behaviour in the PACTEL facility, a medium-scale integral test loop patterned after VVER pressurized water reactors. Flow behaviour over a range of coolant inventories was studied with a small-break experiment. In the small-break experiments, flow stagnation and system repressurization were observed when the water level in the upper plenum fell below the entrances to the hot legs. The cause was attributed to the hot leg loop seals, which are a unique feature of the VVER geometry. At low primary inventories, core cooling was achieved through the boiler-condenser mode. The experiment was simulated using French thermalhydraulic system code CATHARE.

Progress in the U.S. department of energy sponsored in-depth safety assessments of VVER and RBMK reactors

International Nuclear Information System (INIS)

Binder, J.L.; Petri, M.C.; Pasedag, W.F.

2001-01-01

Since the disastrous accident at Chernobyl Nuclear Power Plant Unit 4 in 1986, there has been international recognition of the safety concerns posed by the operation of 67 Soviet-designed commercial nuclear reactors. These reactors are operated in eight countries from the former Soviet Union and its former satellite states in Central and Eastern Europe. The majority of these plants are in the Russian Federation (30 units) and Ukraine (14 units). New plants are in various stages of construction. U.S. support to improve the safety of Soviet-designed reactors over the past decade has been intended to enhance operational safety, provide for risk-reduction measures, and enhance regulatory capability. The U.S. approach to improving the safety of Soviet-designed reactors has matured into a large multi-year program known as the Soviet-Designed Reactor Safety Program that is managed by the U.S. Department of Energy (US DOE). The mission of the program is to implement a self-sustaining nuclear safety improvement program that would lead to internationally accepted safety practices at the plants. Those practices would create a safety culture that would be reflected in the operation, regulation, and professional attitudes of the designers, operators, and regulators of the nuclear facilities. A key component of this larger program has been the Plant Safety Evaluation Program, which supports in-depth safety assessments of VVER and RBMK plants. (author)

Similarities and differences between conventional power and nuclear power

International Nuclear Information System (INIS)

Wang Yingrong

2011-01-01

As the implementation of the national guideline of 'proactively promoting nuclear power development', especially after China decided in 2006 to introduce Westinghouse's AP1000 technology, some of the power groups specialized in conventional power generation, have been participating in the preliminary work and construction of nuclear power projects in certain degrees. Meanwhile, such traditional nuclear power corporations as China National Nuclear Corporation (CNNC) and China Guangdong Nuclear Power Corporation (CGNPC) have also employed some employees with conventional power generation experience. How can these employees who have long been engaged in conventional power generation successfully adapt to the new work pattern, ideology, knowledge, thinking mode and proficiency of nuclear power, so that they can fit in with the work requirements of nuclear power and become qualified as soon as possible? By analyzing the technological, managerial and cultural features of nuclear power, as well as some issues to be kept in mind when engaged in nuclear power, this paper intends to make some contribution to the nuclear power development in the specific period. (author)

Nuclear power in Korea

Energy Technology Data Exchange (ETDEWEB)

Rim, C S [Radioactive Waste Management Centre, Korea Atomic Energy Research Institute, Taejon, Choong-Nam (Korea, Republic of)

1990-07-01

Before addressing the issue of public and utility acceptance of nuclear power in Korea, let me briefly explain the Korean nuclear power program and development plan for a passively safe nuclear power plant in Korea. At present, there are eight PWRs and one CANDU in operation; two PWRs are under construction, and contract negotiations are underway for one more CANDU and two more PWRs, which are scheduled to be completed by 1997,1998 and 1999, respectively. According to a recent forecast for electricity demand in Korea, about fifty additional nuclear power plants with a generating capacity of 1000MWe are required by the year 2030. Until around 2006, Korean standardized nuclear power plants with evolutionary features such as those in the ALWR program are to be built, and a new type of nuclear power plant with passive safety features is expected to be constructed after 2006. The Korean government is making a serious effort to increase public understanding of the safety of nuclear power plants and radioactive waste storage and disposal. In addition, the Korean government has recently introduced a program of benefits for residents near nuclear power plants. By this program, common facilities such as community centers and new roads are constructed, and scholarships are given to the local students. Nuclear power is accepted positively by the utility and reasonably well by the public in Korea.

Nuclear power in Korea

International Nuclear Information System (INIS)

Rim, C.S.

1990-01-01

Before addressing the issue of public and utility acceptance of nuclear power in Korea, let me briefly explain the Korean nuclear power program and development plan for a passively safe nuclear power plant in Korea. At present, there are eight PWRs and one CANDU in operation; two PWRs are under construction, and contract negotiations are underway for one more CANDU and two more PWRs, which are scheduled to be completed by 1997,1998 and 1999, respectively. According to a recent forecast for electricity demand in Korea, about fifty additional nuclear power plants with a generating capacity of 1000MWe are required by the year 2030. Until around 2006, Korean standardized nuclear power plants with evolutionary features such as those in the ALWR program are to be built, and a new type of nuclear power plant with passive safety features is expected to be constructed after 2006. The Korean government is making a serious effort to increase public understanding of the safety of nuclear power plants and radioactive waste storage and disposal. In addition, the Korean government has recently introduced a program of benefits for residents near nuclear power plants. By this program, common facilities such as community centers and new roads are constructed, and scholarships are given to the local students. Nuclear power is accepted positively by the utility and reasonably well by the public in Korea

Minimum throttling feedwater control in VVER-1000 and PWR NPPs

International Nuclear Information System (INIS)

Symkin, B.E.; Thaulez, F.

2004-01-01

This paper presents an approach for the design and implementation of advanced digital control systems that use a minimum-throttling algorithm for the feedwater control. The minimum-throttling algorithm for the feedwater control, i.e. for the control of steam generators level and of the feedwater pumps speed, is applicable for NPPs with variable speed feedwater pumps. It operates in such a way that the feedwater control valve in the most loaded loop is wide open, steam generator level in this loop being controlled by the feedwater pumps speed, while the feedwater control valves in the other loops are slightly throttling under the action of their control system, to accommodate the slight loop imbalances. This has the advantage of minimizing the valve pressure losses hence minimizing the feedwater pumps power consumption and increasing the net MWe. The benefit has been evaluated for specific plants as being roughly 0.7 and 2.4 MW. The minimum throttling mode has the further advantages of lowering the actuator efforts with potential positive impact in actuator life and of minimizing the feedwater pipelines vibrations. The minimum throttling mode of operation has been developed by the Ukrainian company LvivORGRES. It has been applied with great deal of success on several VVER-1000 NPPs, six units of Zaporizhzha in Ukraine plus, with participation of Westinghouse, Kozloduy 5 and 6 in Bulgaria and South Ukraine 1 to 3 in Ukraine. The concept operates with both ON-OFF valves and true control valves. A study, jointly conducted by Westinghouse and LvivORGRES, is ongoing to demonstrate the applicability of the concept to PWRs having variable speed feedwater pumps and having, or installing, digital feedwater control, standalone or as part of a global digital control system. The implementation of the algorithm at VVER-1000 plants provided both safety improvement and direct commercial benefits. The minimum-throttling algorithm will similarly increase the performance of PWRs. The

Cost of nuclear power generation judged by power rate

International Nuclear Information System (INIS)

Hirai, Takaharu

1981-01-01

According to estimation guidance, power rates in general are the proper cost plus the specific compensation and adjustment addition. However, the current system of power rates is of power-source development promotion type involving its tax. The structure of power rate determination must be restudied now especially in connection of nuclear power generation. The cost of nuclear power generation as viewed from power rate is discussed as follows: the fear of military application of power plants, rising plant construction costs, the loophole in fuel cost calculation, unreasonable unit power cost, depreciation and repair cost, business compensation, undue business compensation in nuclear power, the costs of nuclear waste management, doubt concerning nuclear power cost, personnel, pumping-up and power transmission costs in nuclear power, energy balance analysis, nuclear power viewed in entropy, the suppression of power consumption. (J.P.N.)

Nuclear Power in Korea

International Nuclear Information System (INIS)

Ha, Duk-Sang

2009-01-01

Full text: Korea's nuclear power program has been promoted by step-by-step approach; the first stage was 1970's when it depended on the foreign contractors' technology and the second was 1980's when it accumulated lots of technology and experience by jointly implementing the project. Lastly in the third stage in 1990's, Korea successfully achieved the nuclear power technological self-reliance and developed its standard nuclear power plant, so-called Optimized Power Reactor 1000 (OPR 1000). Following the development of OPR 1000, Korea has continued to upgrade the design, known as the Advanced Power Reactor 1400 (APR 1400) and APR+. Korea is one of the countries which continuously developed the nuclear power plant projects during the last 30 years while the other advanced countries ceased the project, and therefore, significant reduction of project cost and construction schedule were possible which benefits from the repetition of construction project. And now, its nuclear industry infrastructure possesses the strong competitiveness in this field.The electricity produced from the nuclear power is 150,958 MWh in 2008, which covers approximately 36% of the total electricity demand in Korea, while the installed capacity of nuclear power is 17,716 MW which is 24% of the total installed capacity. We are currently operating 20 units of nuclear power plants in Korea, and also are constructing 8 additional units (9,600 MW). Korea's nuclear power plants have displayed their excellent operating performance; the average plant capacity factor was 93.4% in 2008, which are about 15% higher than the world average of 77.8%. Moreover, the number of unplanned trips per unit was only 0.35 in 2008, which is the world top class performance. Also currently we are operating four CANDU nuclear units in Korea which are the same reactor type and capacity as the Cernavoda Units. They have been showing the excellent operating performance, of which capacity in 2008 is 92.8%. All the Korean

Typical design/qualification acceptance criteria for newly installed pipelines and equipment components of VVER-type NPPs

International Nuclear Information System (INIS)

Masopust, R.

2003-01-01

This paper describes in general the typical design/qualification acceptance criteria and seismic acceptance criteria in particular that are applicable for important to safety newly installed pipelines and equipment components of VVER-type already existing NPPs, specifically during the design verification phase of this newly installed equipment. These criteria are currently used for VVER 440-213 and VVER 1000 NPPs in Czech Republic and in Slovakia. The similar criteria are also used in Hungary. (author)

Worldwide nuclear power

International Nuclear Information System (INIS)

Royen, J.

1981-01-01

Worldwide nuclear power (WNP) is a companion volume to UPDATE. Our objective in the publication of WNP is to provide factual information on nuclear power programs and policies in foreign countries to U.S. policymakers in the Federal Government who are instrumental in defining the direction of nuclear power in the U.S. WNP is prepared by the Office of the Assistant Secretary for Nuclear Energy from reports obtained from foreign Embassies in Washington, U.S. Embassies overseas, foreign and domestic publications, participation in international studies, and personal communications. Domestic nuclear data is included only where its presence is needed to provide easy and immediate comparisons with foreign data

Nuclear safety in eastern countries. Background of IPSN's actions

International Nuclear Information System (INIS)

1999-01-01

In this document, IPSN presents its opinion about the safety level that might be reached by the nuclear power plants situated in the former-USSR countries. In these countries 2 types of fission reactors are operating: VVER and RBMK with respectively 46 units and 14 units. 3 generations of VVER-type reactors are coexisting: 440 MWe-230, 440 MWe-213 and 1000 MWe-320. The first generation (440 MWe-230) which involves 11 operating units are the least safe and by no means is it possible to make them reach the western standard of safety. The second generation (440 MWe-213) require technical modifications to near western safety standards. The last generation (1000 MWe-320) has safety levels very similar to PWR's if operating procedures are modified and adapted. RBMK-type reactors have been designed in the years 60-70, they suffer from generic defects due to their design, the poor quality of materials and their low reliability. IPSN fears that any incident in such reactors might turn into a major accident. In order to improve nuclear safety in eastern countries, the European Union has launched an international cooperation, the programmes PHARE and TACIS are presented. (A.C.)

The prospect of nuclear energy in Türkiye especially after Fukushima accident

Science.gov (United States)

Şahin, Sümer

2014-09-01

Türkiye considers since mid-50's to use nuclear electricity, but Government and bureaucracy have continuously postponed reactor construction. However, since 2010 the case has gained a real shape. Official agreement has been signed for the construction of 4 units of Russian VVER type reactors with installed power of 4×1200 MWel. It is expected that they will begin to deliver electricity early 20's. Further negotiations are being conducted with Japanese Mitsubashi and French AREVA. The target is to have nuclear electricity by 2023 at the 100th anniversary of Turkish Republic. Turkish Nuclear Energy Strategy aims; • Decrease country's dependency on foreign suppliers of energy sources • Provide fuel supply mix diversification • Utilization of environmentally friendly energy production technologies Possess advanced and prestigious power generation technologies.

In vessel retention for VVER 1000 - Experimental work

International Nuclear Information System (INIS)

Batek, D.

2015-01-01

After Fukushima accident, the nuclear community realized that it is necessary to have strategy and solution for severe accident management. In Vessel Retention (IVR) of corium is an important strategy to mitigate the consequences of a severe accident. In this poster the author reviews the present status of experimental works made by UJV (Czech Republic) from 2012 until now, on the IVR strategy specifically applied for the VVER 1000 unit. The BESTH 1 experiment was prepared to test the behavior of the RPV (Reactor Pressure Vessel) surface under 2 configurations: clean and corroded. BESTH 2 experiment is a modification of BESTH 1 experiment in order to get greater thermal fluxes. The BESTH 3 facility is a large scale experiment that is under extensive design (2016-2017) whose main objective will be to investigate the results of vast analytical works made by experts with specialization of severe accident phenomenology

Nuclear power generation

International Nuclear Information System (INIS)

Hirao, Katumi; Sato, Akira; Kaimori, Kimihiro; Kumano, Tetsuji

2001-01-01

Nuclear power generation for commercial use in Japan has passed 35 years since beginning of operation in the Tokai Nuclear Power Station in 1966, and has 51 machines of reactor and about 44.92 MW of total output of equipment scale in the 21st century. However, an environment around nuclear energy becomes severer at present, and then so many subjects to be overcome are remained such as increased unreliability of the public on nuclear energy at a chance of critical accident of the JCO uranium processing facility, delay of pull-thermal plan, requirement for power generation cost down against liberalization of electric power, highly aging countermeasure of power plant begun its operation as its Genesis, and so on. Under such conditions, in order that nuclear power generation in Japan survives as one of basic electric source in future, it is necessary not only to pursue safety and reliability of the plant reliable to the public, but also to intend to upgrade its operation and maintenance by positively adopting good examples on operational management method on abroad and to endeavor further upgrading of application ratio of equipments and reduction of generation cost. Here were outlined on operation conditions of nuclear power stations in Japan, and introduced on upgrading of their operational management and maintenance management. (G.K.)

Nuclear power plants

International Nuclear Information System (INIS)

Margulova, T.Ch.

1976-01-01

The textbook focuses on the technology and the operating characteristics of nuclear power plants equiped with pressurized water or boiling water reactors, which are in operation all over the world at present. The following topics are dealt with in relation to the complete plant and to economics: distribution and consumption of electric and thermal energy, types and equipment of nuclear power plants, chemical processes and material balance, economical characteristics concerning heat and energy, regenerative preheating of feed water, degassing and condenser systems, water supply, evaporators, district heating systems, steam generating systems and turbines, coolant loops and pipes, plant siting, ventilation and decontamination systems, reactor operation and management, heat transfer including its calculation, design of reactor buildings, and nuclear power plants with gas or sodium cooled reactors. Numerous technical data of modern Soviet nuclear power plants are included. The book is of interest to graduate and post-graduate students in the field of nuclear engineering as well as to nuclear engineers

Elecnuc. Nuclear power plants worldwide

International Nuclear Information System (INIS)

1998-01-01

This small folder presents a digest of some useful information concerning the nuclear power plants worldwide and the situation of nuclear industry at the end of 1997: power production of nuclear origin, distribution of reactor types, number of installed units, evolution and prediction of reactor orders, connections to the grid and decommissioning, worldwide development of nuclear power, evolution of power production of nuclear origin, the installed power per reactor type, market shares and exports of the main nuclear engineering companies, power plants constructions and orders situation, evolution of reactors performances during the last 10 years, know-how and development of nuclear safety, the remarkable facts of 1997, the future of nuclear power and the energy policy trends. (J.S.)

Modelling of thermal mechanical behaviour of high burn-Up VVER fuel at power transients with special emphasis on the impact of fission gas induced swelling of fuel pellets

International Nuclear Information System (INIS)

Novikov, V.; Medvedev, A.; Khvostov, G.; Bogatyr, S.; Kuzetsov, V.; Korystin, L.

2005-01-01

This paper is devoted to the modelling of unsteady state mechanical and thermo-physical behaviour of high burn-up VVER fuel at a power ramp. The contribution of the processes related to the kinetics of fission gas to the consequences of pellet-clad mechanical interaction is analysed by the example of integral VVER-440 rod 9 from the R7 experimental series, with a pellet burn-up in the active part at around 60 MWd/kgU. This fuel rod incurred ramp testing with a ramp value ΔW 1 ∼ 250 W/cm in the MIR research reactor. The experimentally revealed residual deformation of the clad by 30-40 microns in the 'hottest' portion of the rod, reaching a maximum linear power of up to 430 W/cm, is numerically justified on the basis of accounting for the unsteady state swelling and additional degradation of fuel thermal conductivity due to temperature-induced formation and development of gaseous porosity within the grains and on the grain boundaries. The good prediction capability of the START-3 code, coupled with the advanced model of fission gas related processes, with regard to the important mechanical (residual deformation of clad, pellet-clad gap size, central hole filling), thermal physical (fission gas release) and micro-structural (profiles of intra-granular concentration of the retained fission gas and fuel porosity across a pellet) consequences of the R7 test is shown. (authors)

Nuclear power and nuclear weapons

International Nuclear Information System (INIS)

Vaughen, V.C.A.

1983-01-01

The proliferation of nuclear weapons and the expanded use of nuclear energy for the production of electricity and other peaceful uses are compared. The difference in technologies associated with nuclear weapons and nuclear power plants are described

Verification of the Korsar code on results of experiments executed on the PSB-VVER facility

International Nuclear Information System (INIS)

Roginskaya, V.L.; Pylev, S.S.; Elkin, I.V.

2005-01-01

Full text of publication follows: Paper represents some results of computational research executed within the framework of verification of the KORSAR thermal hydraulic code. This code was designed in the NITI by A.P. Aleksandrov (Russia). The general purpose of the work was development of a nodding scheme of the PSB-VVER integral facility, scheme testing and computational modelling of the experiment 'The PSB-VVER Natural Circulation Test With Stepwise Reduction of the Primary Inventory'. The NC test has been performed within the framework of the OECD PSB-VVER Project (task no. 3). This Project is focused upon the provision of experimental data for codes assessment with regard to VVER analysis. Paper presents a nodding scheme of the PSB-VVER facility and results of pre- and post-test calculations of the specified experiment, obtained with the KORSAR code. The experiment data and the KORSAR pre-test calculation results are in good agreement. A post-test calculation of the experiment with KORSAR code has been performed in order to assess the code capability to simulate the phenomena relevant to the test. The code showed a reasonable prediction of the phenomena measured in the experiment. (authors)

Verification of the Korsar code on results of experiments executed on the PSB-VVER facility

Energy Technology Data Exchange (ETDEWEB)

Roginskaya, V.L.; Pylev, S.S.; Elkin, I.V. [NSI RRC ' Kurchatov Institute' , Kurchatov Sq., 1, Moscow, 123182 (Russian Federation)

2005-07-01

Full text of publication follows: Paper represents some results of computational research executed within the framework of verification of the KORSAR thermal hydraulic code. This code was designed in the NITI by A.P. Aleksandrov (Russia). The general purpose of the work was development of a nodding scheme of the PSB-VVER integral facility, scheme testing and computational modelling of the experiment 'The PSB-VVER Natural Circulation Test With Stepwise Reduction of the Primary Inventory'. The NC test has been performed within the framework of the OECD PSB-VVER Project (task no. 3). This Project is focused upon the provision of experimental data for codes assessment with regard to VVER analysis. Paper presents a nodding scheme of the PSB-VVER facility and results of pre- and post-test calculations of the specified experiment, obtained with the KORSAR code. The experiment data and the KORSAR pre-test calculation results are in good agreement. A post-test calculation of the experiment with KORSAR code has been performed in order to assess the code capability to simulate the phenomena relevant to the test. The code showed a reasonable prediction of the phenomena measured in the experiment. (authors)

Economics of nuclear power projects

International Nuclear Information System (INIS)

Chu, I.H.

1985-01-01

Nuclear power development in Taiwan was initiated in 1956. Now Taipower has five nuclear units in smooth operation, one unit under construction, two units under planning. The relatively short construction period, low construction costs and twin unit approach had led to the significant economical advantage of our nuclear power generation. Moreover betterment programmes have further improved the availability and reliability factors of our nuclear power plants. In Taipower, the generation cost of nuclear power was even less than half of that of oil-fired thermal power in the past years ever since the nuclear power was commissioned. This made Taipower have more earnings and power rates was even dropped down in March 1983. As Taiwan is short of energy sources and nuclear power is so well-demonstrated nuclear power will be logically the best choice for Taipower future projects

Hydrogen mixing analyses for a VVER containment.

Energy Technology Data Exchange (ETDEWEB)

Sienicki, J.J.; Kostka, P.; Techy, Z.

2002-02-25

Hydrogen combustion may represent a threat to containment integrity in a VVER-440/213 plant owing to the combination of high pressure and high temperature. A study has been carried out using the GASFLOW 2.1 three-dimensional CFD code to evaluate the hydrogen distribution in the containment during a beyond design basis accident. The VVER-440/213 containment input model consists of two 3D blocks connected via one-dimensional (1D) ducts. One 3D block contains the reactor building and the accident localization tower with the suppression pools. Another 3D block models the air traps. 1D ducts represent the check valves connecting the accident localization tower with the air traps. The VVER pressure suppression system, called ''bubbler condenser,'' was modeled as a distributed heat sink with water thermodynamic properties. This model accounts for the energy balance. However, it is not currently possible to model dynamic phenomena associated with the water pools (e.g., vent clearing, level change). The GASFLOW 2.1 calculation gave detailed results for the spatial distribution of thermal-hydraulic parameters and gas concentrations. The range and trend of the parameters are reasonable and valuable. There are particularly interesting circulation patterns around the steam generators, in the bubbler tower and other primary system compartments. In case of the bubbler tower, concentration and temperature contour plots show an inhomogeneous distribution along the height and width, changing during the accident. Hydrogen concentrations also vary within primary system compartments displaying lower as well as higher (up to 13-20% and higher) values in some nodes. Prediction of such concentration distributions was not previously possible with lumped parameter codes. GASFLOW 2.1 calculations were compared with CONTAIN 1.2 (lumped parameter code) results. Apart from the qualitatively similar trends, there are, for the time being, quantitative differences between the

Accelerating nuclear power standards development and promoting sound nuclear power development in China

International Nuclear Information System (INIS)

Yang Changli

2008-01-01

The paper expounds the importance of quickening establishment and perfection of nuclear power standard system in China, analyzes achievements made and problems existed during the development of nuclear power standards, put forward proposals to actively promote the work in this regard, and indicates that CNNC will further strengthen the standardization work, enhance coordination with those trades related to nuclear power standards, and jointly promote the development of nuclear power standards. (authors)

Improving the VVER-440 fuel design and technology

International Nuclear Information System (INIS)

Aksenov, P.; Bondar, Y.; Kolosovsky, Y.; Kochergin, V.; Luzan, Y.; Malakhov, A.; Krapivtsev, V.; Bauman, N.; Shumeev, A.; Filippov, V.

2009-01-01

Operational performance of VVER-440 fuel has long been demonstrating good reliability of the fuel. However, assembly failures occur, and fuel suppliers should always take measures to maintain its reliability. For several years, OAO MSZ has been fabricating working assemblies with detachable shrouds and removable fuel rods. The next step is the supply of demountable assemblies to allow inspection or repair of fuel rods after removal of the shroud. With the help of corresponding program the Russian organizations have carried out research and development work to advance and study operational features of demountable VVER-440 CFAs. The main engineering solutions are consistent with the working assemblies. The pilot demountable CFAs are running in the Kola-4 core. The obtained results can be used when deciding on the demountable CFAs delivery issues. The experiment-calculated research results of coolant mixing in the present design VVER-440 have been analysed. It has been found out that coolant mixing in the WA head is incomplete and that is why leading to conservatism when determining the reactor operational limits. The proposed WA head design includes an upgraded bumper grid with additional planes intensifying coolant mixing in the head. The bumper grid drawing and a pilot model is available. The thermohydraulics and rigidity features of the proposed design have been studied by experiment-calculated methods

Nuclear Power Today and Tomorrow

International Nuclear Information System (INIS)

Bychkov, Alexander

2013-01-01

Worldwide, with 437 nuclear power reactors in operation and 68 new reactors under construction, nuclear power's global generating capacity reached 372.5 GW(e) at the end of 2012. Despite public scepticism, and in some cases fear, which arose following the March 2011 Fukushima Daiichi nuclear accident, two years later the demand for nuclear power continues to grow steadily, albeit at a slower pace. A significant number of countries are pressing ahead with plans to implement or expand their nuclear power programmes because the drivers toward nuclear power that were present before Fukushima have not changed. These drivers include climate change, limited fossil fuel supply, and concerns about energy security. Globally, nuclear power looks set to continue to grow steadily, although more slowly than was expected before the Fukushima Daiichi nuclear accident. The IAEA's latest projections show a steady rise in the number of nuclear power plants in the world in the next 20 years. They project a growth in nuclear power capacity by 23% by 2030 in the low projection and by 100% in the high projection. Most new nuclear power reactors planned or under construction are in Asia. In 2012 construction began on seven nuclear power plants: Fuqing 4, Shidaowan 1, Tianwan 3 and Yangjiang 4 in China; Shin Ulchin 1 in Korea; Baltiisk 1 in Russia; and Barakah 1 in the United Arab Emirates. This increase from the previous year's figures indicates an on-going interest and commitment to nuclear power and demonstrates that nuclear power is resilient. Countries are demanding new, innovative reactor designs from vendors to meet strict requirements for safety, national grid capacity, size and construction time, which is a sign that nuclear power is set to keep growing over the next few decades.

Expert evaluation in NPP safety important systems licensing process

International Nuclear Information System (INIS)

Mikhail, A Yastrebenetsky; Vasilchenko, V.N.

2001-01-01

Expert evaluation of nuclear power plant safety important systems modernization is an integral part of these systems licensing process. The paper contains some aspects of this evaluation which are based on Ukrainian experience of VVER-1000 and VVER-440 modernization. (authors)

Expert evaluation in NPP safety important systems licensing process

Energy Technology Data Exchange (ETDEWEB)

Mikhail, A Yastrebenetsky; Vasilchenko, V.N. [Ukrainian State Scientific Technical Center of Nuclear and Radiation Safety (Ukraine)

2001-07-01

Expert evaluation of nuclear power plant safety important systems modernization is an integral part of these systems licensing process. The paper contains some aspects of this evaluation which are based on Ukrainian experience of VVER-1000 and VVER-440 modernization. (authors)

USSR reins-in nuclear plans

International Nuclear Information System (INIS)

Perera, Judith.

1989-01-01

The USSR had hoped to double its nuclear capacity by the year 2000 to provide 20 per cent of its electricity. But this may no longer be possible in the face of the growing anti-nuclear movement allowed by Glasnost and given a focus by Chernobyl. Local protest has forced Moscow to drop its plans to build one of the world's biggest nuclear power plants at Ignalina in Lithuania. Although two 1,500 MW units are operating, there is national opposition to two more being built there. A year ago the Government had to scrap plans to build a 1,000MW VVER (pressurised water reactor) at Krasnador near the Black Sea, because of high seismic activity in the area. In the Ukraine, building has also stopped at the Chigirin plant. Plans to build nuclear heat and power plants at Odessa and Kharkov were cancelled last July. Construction of a nuclear power and heat plant at Minsk has been suspended and the Byelorussian government has proposed to Moscow that it should be redesigned to run on gas. A planned nuclear power and heat plant in Gorky and a plant being built in the Crimea are in doubt. Armenia's two reactors in the Ararat valley are to be closed and converted to a thermal plant, following increased concern after the 1988 earthquake. The USSR are looking at other energy sources, geothermal, solar, wind and wave. (author)

Issues and remedies for secondary system of PWR/VVER

International Nuclear Information System (INIS)

Nordmann, Francis; Odar, Suat; Rochester, Dewey

2012-09-01

Secondary side degradation of steam generators (SG) and Flow Accelerated Corrosion (FAC) in the secondary system have been for a long time important issues in PWR and VVER types of Nuclear Power Plants. With the evolution of the design, the most important issues are progressively moving from secondary side corrosion of Alloy 600 SG tubing, which is being replaced, to a larger variety of risks associated with potential inadequate chemistries. As far as FAC of carbon steel is concerned, the evolution of treatment selection for minimizing corrosion products transport toward the SG, as well as progressive replacement of components in the feedwater train, decreases the risk of dramatic failures which have occurred in the past. After having briefly explained the reason for the past problems encountered in the secondary system of PWR and VVER, this paper evaluates the risk associated with various impurities or contaminants that may be present in the secondary system and how to mitigate them in the most appropriate, efficient, economical and environmental friendly way. The covered species are sodium, calcium, magnesium, chloride, sulfate and sulfur compounds, fluorides, organic compounds, silica, oxygen, lead, ion exchange resins. This paper also proposes the best remedies for mitigating the new issues that may be encountered in operating plants or units under construction. These are mainly: - Selecting a steam water treatment able to minimize the quantity of corrosion products transported toward the SG; - Mitigating the risk of Flow Induced Vibration by a proper control of deposits in sensitive areas; - Minimizing the risk of concentration of impurities in local areas where they may induce corrosion; - Avoiding the presence of abnormal quantities of some species in SG, such as the detrimental presence of lead and ion exchange resin debris or the controversial presence of organic compounds; - Optimizing costs of maintenance activities (SG mechanical, chemical cleaning

Nuclear power and other energy

International Nuclear Information System (INIS)

Doederlein, J.M.

1975-01-01

A comparison is made between nuclear power plants, gas-fuelled thermal power plants and oil-fired thermal power plants with respect to health factors, economy, environment and resource exploitation, with special reference to the choice of power source to supplement Norwegian hydroelectric power. Resource considerations point clearly to nuclear power, but, while nuclear power has an overall economic advantage, the present economic situation makes its heavy capital investment a disadvantage. It is maintained that nuclear power represents a smaller environmental threat than oil or gas power. Finally, statistics are given showing that nuclear power involves smaller fatality risks for the population than many other hazards accepted without question. (JIW)

Nuclear Security for Floating Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Skiba, James M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Scherer, Carolynn P. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2015-10-13

Recently there has been a lot of interest in small modular reactors. A specific type of these small modular reactors (SMR,) are marine based power plants called floating nuclear power plants (FNPP). These FNPPs are typically built by countries with extensive knowledge of nuclear energy, such as Russia, France, China and the US. These FNPPs are built in one country and then sent to countries in need of power and/or seawater desalination. Fifteen countries have expressed interest in acquiring such power stations. Some designs for such power stations are briefly summarized. Several different avenues for cooperation in FNPP technology are proposed, including IAEA nuclear security (i.e. safeguards), multilateral or bilateral agreements, and working with Russian design that incorporates nuclear safeguards for IAEA inspections in non-nuclear weapons states

Comparison of hydrogen generation for TVSM and TVSA fuel assemblies for water water energy reactor (VVER)-1000

International Nuclear Information System (INIS)

Stefanova, A.E.; Groudev, P.P.; Atanasova, B.P.

2009-01-01

This paper presents the results received during investigation of hydrogen generation for both types fuel assemblies-the old modernistic type of fuel assemblies (TVSM) and recently installed new one alternative type of fuel assemblies (TVSA) in case of severe accident. There are some differences between both types FAs. They have different geometry as well as different burnable poisons. To investigate behavior of new fuel assemblies during the severe conditions it have been performed comparison of fuel behavior of old type TVSM fuel assembly to new one TVSA. To perform this investigation it has been used MELCOR 'input model' for Kozloduy Nuclear Power Plant (KNPP) VVER 1000. The model was developed by Institute for Nuclear Research and Nuclear Energy-Bulgarian Academy of Sciences (INRNE-BAS) for investigation of severe accident scenarios and Probabilistic Safety Analyses (PSA) level 2. The model provides a significant analytical capability for the Bulgarian technical specialists, working in the field of the NPP safety, for analysis of core and containment damaged states and the estimation of radionuclides release outside fuel cladding. It was accepted criteria for vessel integrity about hydrogen concentration to be 8%. This criterion was based on the decision of RSK (Germany commission for reactor safety). Generally based on the received results it was made conclusion that using both types of fuel assemblies it was not disturbance safety conditions of NPP

OECD/DOE/CEA VVER-1000 Coolant Transient Benchmark. Summary Record of the Third Workshop (V1000-CT3)

International Nuclear Information System (INIS)

2005-01-01

The overall objective of the VVER-1000 coolant transient (V1000CT) benchmark is to assess computer codes used in the safety analysis of VVER power plants, specifically for their use in analysis of reactivity transients in a VVER-1000. The V1000CT benchmark consists of two phases: V1000CT-1 is a simulation of the switching on of one main coolant pump (MCP) when the other three MCPs are in operation, and V1000CT-2 concerns calculation of coolant mixing tests and main steam line break (MSLB) scenarios. Each of the two phases contains three exercises. The reference problem chosen for simulation in Phase 1 is a MCP switching on when the other three main coolant pumps are in operation in a VVER-1000. This event is characterized by rapid increase in the flow through the core resulting in a coolant temperature decrease, which is spatially dependent. This leads to insertion of spatially distributed positive reactivity due to the modelled feedback mechanisms and non-symmetric power distribution. Simulation of the transient requires evaluation of core response from a multi-dimensional perspective (coupled three-dimensional neutronics/core thermal-hydraulics) supplemented by a one-dimensional simulation of the remainder of the reactor coolant system. Three exercises are defined in the framework of Phase 1: a) Exercise 1 - Point kinetics plant simulation; b) Exercise 2 - Coupled 3-D neutronics/core thermal-hydraulics response evaluation; c) Exercise 3 - Best-estimate coupled 3-D core/plant system transient modelling. In addition to the measured (experiment) scenario, extreme calculation scenarios were defined in the frame of Exercise 3 for better testing 3-D neutronics/thermal-hydraulics techniques. The proposals concerned: rod ejection simulations with scram set points at two different power levels. The technical topics presented at this workshop were: Review of the benchmark activities after the 2. Workshop; - Discussion of participant's feedback and introduced modifications

Nuclear power costs

International Nuclear Information System (INIS)

1963-01-01

A report prepared by the IAEA Secretariat and presented to the seventh session of the Agency's General Conference says that information on nuclear power costs is now rapidly moving from the domain of uncertain estimates to that of tested factual data. As more and more nuclear power stations are being built and put into operation, more information on the actual costs incurred is becoming available. This is the fourth report on nuclear power costs to be submitted to the IAEA General Conference. The report last year gave cost information on 38 nuclear power projects, 17 of which have already gone into operation. Certain significant changes in the data given last year are included-in the present report; besides, information is given on seven new plants. The report is divided into two parts, the first on recent developments and current trends in nuclear power costs and the second on the use of the cost data for economic comparisons. Both stress the fact that the margin of uncertainty in the basic data has lately been drastically reduced. At the same time, it is pointed out, some degree of uncertainty is inherent in the assumptions made in arriving at over-all generating cost figures, especially when - as is usually the case - a nuclear plant is part of an integrated power system

Modernizing the VVER-440/230

International Nuclear Information System (INIS)

Mink, F.J.

1991-01-01

The modernization of the VVER-440/230s is not fundamentally different from backfit projects on older pressurized water reactors which Westinghouse has completed elsewhere. However, carrying out such programmes only makes sense if the plants are expected to continue operation for their projected life or beyond. This clearly requires some licensing and political stability; both are essential if investors in the upgrading project are to be found. (author)

Nuclear power experience

International Nuclear Information System (INIS)

1983-01-01

The International Conference on Nuclear Power Experience, organized by the International Atomic Energy Agency, was held at the Hofburg Conference Center, Vienna, Austria, from 13 to 17 September 1982. Almost 1200 participants and observers from 63 countries and 20 organizations attended the conference. The 239 papers presented were grouped under the following seven main topics: planning and development of nuclear power programmes; technical and economic experience of nuclear power production; the nuclear fuel cycle; nuclear safety experience; advanced systems; international safeguards; international co-operation. The proceedings are published in six volumes. The sixth volume contains a complete Contents of Volume 1 to 5, a List of Participants, Authors and Transliteration Indexes, a Subject Index and an Index of Papers by Number

Worldwide nuclear power

International Nuclear Information System (INIS)

Anon.

1981-01-01

Worldwide Nuclear Power (WNP) is a companion volume to Update. Our objective in the publication of WNP is to provide factual information on nuclear power programs and policies in foreign countries to U.S. policymakers in the Federal Government. Facts about the status of nuclear activities abroad should be available to those who are instrumental in defining the direction of nuclear power in the U.S. WNP is prepared by the Office of Nuclear Energy from reports obtained from foreign embassies in Washington, U.S. Embassies overseas, foreign and domestic publications, participation in international studies, and personal communications. It consists of two types of information, tabular and narrative. Domestic nuclear data is included only where its presence is needed to provide easy and immediate comparisons with foreign data. In general, complete U.S. information will be found in Update

Nuclear power in Canada

International Nuclear Information System (INIS)

1980-01-01

The Canadian Nuclear Association believes that the CANDU nuclear power generation system can play a major role in achieving energy self-sufficiency in Canada. The benefits of nuclear power, factors affecting projections of electric power demand, risks and benefits relative to other conventional and non-conventional energy sources, power economics, and uranium supply are discussed from a Canadian perspective. (LL)

Nuclear power and the nuclear fuel cycle

Energy Technology Data Exchange (ETDEWEB)

NONE

1976-07-01

The IAEA is organizing a major conference on nuclear power and the nuclear fuel cycle, which is to be held from 2 to 13 May 1977 in Salzburg, Austria. The programme for the conference was published in the preceding issue of the IAEA Bulletin (Vol.18, No. 3/4). Topics to be covered at the conference include: world energy supply and demand, supply of nuclear fuel and fuel cycle services, radioactivity management (including transport), nuclear safety, public acceptance of nuclear power, safeguarding of nuclear materials, and nuclear power prospects in developing countries. The articles in the section that follows are intended to serve as an introduction to the topics to be discussed at the Salzburg Conference. They deal with the demand for uranium and nuclear fuel cycle services, uranium supplies, a computer simulation of regional fuel cycle centres, nuclear safety codes, management of radioactive wastes, and a pioneering research project on factors that determine public attitudes toward nuclear power. It is planned to present additional background articles, including a review of the world nuclear fuel reprocessing situation and developments in the uranium enrichment industry, in future issues of the Bulletin. (author)

Validation matrix for the assessment of thermal-hydraulic codes for VVER LOCA and transients. A report by the OECD support group on the VVER thermal-hydraulic code validation matrix

International Nuclear Information System (INIS)

2001-06-01

This report deals with an internationally agreed experimental test facility matrix for the validation of best estimate thermal-hydraulic computer codes applied for the analysis of VVER reactor primary systems in accident and transient conditions. Firstly, the main physical phenomena that occur during the considered accidents are identified, test types are specified, and test facilities that supplement the CSNI CCVMs and are suitable for reproducing these aspects are selected. Secondly, a list of selected experiments carried out in these facilities has been set down. The criteria to achieve the objectives are outlined. The construction of VVER Thermal-Hydraulic Code Validation Matrix follows the logic of the CSNI Code Validation Matrices (CCVM). Similar to the CCVM it is an attempt to collect together in a systematic way the best sets of available test data for VVER specific code validation, assessment and improvement, including quantitative assessment of uncertainties in the modelling of phenomena by the codes. In addition to this objective, it is an attempt to record information which has been generated in countries operating VVER reactors over the last 20 years so that it is more accessible to present and future workers in that field than would otherwise be the case. (authors)

Innovated feed water distributing system of VVER steam generators

International Nuclear Information System (INIS)

Matal, O.; Sousek, P.; Simo, T.; Lehota, M.; Lipka, J.; Slugen, V.

2000-01-01

Defects in feed water distributing system due to corrosion-erosion effects have been observed at many VVER 440 steam generators (SG). Therefore analysis of defects origin and consequently design development and testing of a new feed water distributing system were performed. System tests in-situ supported by calculations and comparison of measured and calculated data were focused on demonstration of long term reliable operation, definition of water flow and water chemical characteristics at the SG secondary side and their measurements and study of dynamic characteristics needed for the innovated feed water distributing system seismic features approval. The innovated feed water distributing system was installed in the SGs of two VVER units already. (author)

Core design experience of WWER-440 reactors when they working on increased power level

International Nuclear Information System (INIS)

Adeev, V.; Panov, A.; Melenchuk, I.

2015-01-01

The Kola NPP continues commercial operation of 2nd generation fuel (FA-2) and trial operation of 3rd generation fuel (FA-3), which has a number of design features providing the best operational characteristics. This report gives the results of VVER-440 core operation with FA-2 and FA-3 with enrichment increased up to 4.87%, and at the power level uprated to 107% of nominal power level. Brief analysis of obtained data is carried out. Peculiarities and techniques of developing loading patterns with new types of nuclear fuel for operation at the uprated power level are reviewed. (authors)

Development of nuclear power

Energy Technology Data Exchange (ETDEWEB)

NONE

1962-01-15

An extensive discussion of problems concerning the development of nuclear power took place at the fifth regular session of the IAEA General Conference in September-October 1961. Not only were there many references in plenary meetings to the nuclear power plans of Member States, but there was also a more specific and detailed debate on the subject, especially on nuclear power costs, in the Program, Technical and Budget Committee of the Conference. The Conference had before it a report from the Board of Governors on the studies made by the Agency on the economics of nuclear power. In addition, it had been presented with two detailed documents, one containing a review of present-day costs of nuclear power and the other containing technical and economic information on several small and medium-sized power reactors in the United States. The Conference was also informed of the report on methods of estimating nuclear power costs, prepared with the assistance of a panel of experts convened by the Agency, which was reviewed in the July 1961 issue of this Bulletin

Development of nuclear power

International Nuclear Information System (INIS)

1962-01-01

An extensive discussion of problems concerning the development of nuclear power took place at the fifth regular session of the IAEA General Conference in September-October 1961. Not only were there many references in plenary meetings to the nuclear power plans of Member States, but there was also a more specific and detailed debate on the subject, especially on nuclear power costs, in the Program, Technical and Budget Committee of the Conference. The Conference had before it a report from the Board of Governors on the studies made by the Agency on the economics of nuclear power. In addition, it had been presented with two detailed documents, one containing a review of present-day costs of nuclear power and the other containing technical and economic information on several small and medium-sized power reactors in the United States. The Conference was also informed of the report on methods of estimating nuclear power costs, prepared with the assistance of a panel of experts convened by the Agency, which was reviewed in the July 1961 issue of this Bulletin

Nuclear power generation incorporating modern power system practice

CERN Document Server

Myerscough, PB

1992-01-01

Nuclear power generation has undergone major expansion and developments in recent years; this third edition contains much revised material in presenting the state-of-the-art of nuclear power station designs currently in operation throughout the world. The volume covers nuclear physics and basic technology, nuclear station design, nuclear station operation, and nuclear safety. Each chapter is independent but with the necessary technical overlap to provide a complete work on the safe and economic design and operation of nuclear power stations.

Problems and experience of ensuring nuclear safety in NPP spent fuel storage facilities in Russia

International Nuclear Information System (INIS)

Vnukov, Victor S.; Ryazanov, Boris G.

2003-01-01

The amount of Nuclear Power Plant (NPP) spent fuel in special storage facilities of Russia runs to more than 15000 tons and the annual growth is equal to about 850 tons. The storage facilities for spent nuclear fuel from the main nuclear reactors of Russia (RBMK-1000, VVER-1000, BN-600, EGP-6) were designed in the 60s - 70s. In the last years when the concept of closed fuel cycle and safety requirements had changed, the need was generated to have the nuclear storage facilities more crowded. First of all it is due to the necessity to increase the storage capacity because the RBMK-1000, VVER-1000, EGP-6 fuel is not reprocessed. So there comes the need for the facilities of a bigger capacity which meet the current safety requirements. The paper presents the results of studies of the most important nuclear safety issues, in particular: development of regulatory requirements; analysis of design-basis and beyond-the design-basis accidents (DBA and BDBA); computation code development and verification; justification of nuclear safety when water density goes down; the use of burn-up fraction values; the necessity and possibility to experimentally study the storage facility subcriticality; development of storage norms and rules for new types of fuel assemblies with mixed fuel and burnable poison. (author)

Development of nuclear power

International Nuclear Information System (INIS)

1960-01-01

The discussion on the development of nuclear power took place on 28 September 1960 in Vienna. In his opening remarks, Director General Cole referred to the widespread opinion that 'the prospect of cheap electricity derived from nuclear energy offers the most exciting prospect for improving the lot of mankind of all of the opportunities for uses of atomic energy'. He then introduced the four speakers and the moderator of the discussion, Mr. H. de Laboulaye, IAEA Deputy Director General for Technical Operations. n the first part of the discussion the experts addressed themselves in turn to four topics put forward by the moderator. These were: the present technical status of nuclear power, the present costs of nuclear power, prospects for future reductions in the cost of nuclear power, and applications of nuclear power in less-developed areas

Nuclear power: European report

International Nuclear Information System (INIS)

Anon.

2005-01-01

In 2004, nuclear power plants were operated and/or built in eighteen European countries. Thirteen of these countries are members of EU-25. Five of the ten countries joining the European Union on May 1, 2004 operate nuclear power stations. A total of 206 power reactors with a gross power of 181,941 MWe and a net power of 172,699 MWe were in operation at the end of the year. In 2004, one nuclear power plant was commissioned in Russia (Kalinin 3), two (Kmelnitzki 2 and Rowno 4) in Ukraine. Five nuclear power plants were decommissioned in Europe in the course of 2004. As announced in 2000, the Chapelcross 1 to Chapelcross 4 plants in Britain were shut down for economic reasons. In Lithuania, the Ignalina 1 unit was disconnected from the power grid, as had been demanded by the EU Commission within the framework of the negotiations about the country's accession to the EU. As a result of ongoing technical optimization in some plants, involving increases in reactor power or generator power as well as commissioning of plants of higher capacity, nuclear generating capacity increased by approx. 1.5 GW. In late 2004, four nuclear generating units were under construction in Finland (1), Romania (1), and Russia (2). 150 nuclear power plants were operated in thirteen states of the European Union (EU-25), which is sixteen more than the year before as a consequence of the accession of new countries. They had an aggregate gross power of 137,943 MWe and a net power of 131,267 MWe, generating approx. 983 billion gross kWh of electricity in 2003, thus again contributing some 32% to the public electricity supply in the EU-25. In largest share of nuclear power in electricity generation is found in Lithuania (80%), followed by 78% in France, 57% in the Slovak Republic, 56% in Belgium, and 46% in Ukraine. In several countries not operating nuclear power plants of their own, such as Italy, Portugal, and Austria, nuclear power makes considerable contributions to public electricity supply as

Delayed Neutron Fraction (beta-effective) Calculation for VVER 440 Reactor

International Nuclear Information System (INIS)

Hascik, J.; Michalek, S.; Farkas, G.; Slugen, V.

2008-01-01

Effective delayed neutron fraction (β eff ) is the main parameter in reactor dynamics. In the paper, its possible determination methods are summarized and a β eff calculation for a VVER 440 power reactor as well as for training reactor VR1 using stochastic transport Monte Carlo method based code MCNP5 is made. The uncertainties in determination of basic delayed neutron parameters lead to the unwished conservatism in the reactor control system design and operation. Therefore, the exact determination of the β eff value is the main requirement in the field of reactor dynamics. The interest in the delayed neutron data accuracy improvement started to increase at the end of 80-ties and the beginning of 90-ties, after discrepancies among the results of experiments and measurements what do you mean differences between different calculation approaches and experimental results. In consequence of difficulties in β eff experimental measurement, this value in exact state is determined by calculations. Subsequently, its reliability depends on the calculation method and the delayed neutron data used. An accurate estimate of β eff is essential for converting reactivity, as measured in dollars, to an absolute reactivity and/or to an absolute k eff . In the past, k eff has been traditionally calculated by taking the ratio of the adjoint- and spectrum-weighted delayed neutron production rate to the adjoint- and spectrum-weighted total neutron production rate. An alternative method has also been used in which β eff is calculated from simple k-eigenvalue solutions. The summary of the possible β eff determination methods can be found in this work and also a calculation of β eff first for the training reactor VR1 in one operation state and then for VVER 440 power reactor in two different operation states are made using the prompt method, by MCNP5 code.(author)

VVER-1000 RPV Head Examination Control System

International Nuclear Information System (INIS)

Erak, Z.; Gortan, K.

2006-01-01

This article presents the electronic system used for automated NDT examination of VVER-1000 Reactor Pressure Vessel Head (RPVH). The control system drives the inspection tool with end-effectors to needed position. When the final position is reached, the eddy current and ultra sound acquisition system performs the data acquisition. The system is composed of 3 layers. The first layer is the hardware layer consisting of motors driving the tool and end-effectors along with sensors needed to obtain the positioning data. The second layer is the MAC-8 control system performing basic monitoring and control routines as an interconnection between first and third layer. The third layer is the control software, running on PC, which is used as a human-machine-interface. Presentation contains details of examination techniques with focus on eddy current examination as well as details on manipulator and end effectors developed by Inetec for VVER-1000 RPVH examination.(author)

Transmutation of actinides in power reactors.

Science.gov (United States)

Bergelson, B R; Gerasimov, A S; Tikhomirov, G V

2005-01-01

Power reactors can be used for partial short-term transmutation of radwaste. This transmutation is beneficial in terms of subsequent storage conditions for spent fuel in long-term storage facilities. CANDU-type reactors can transmute the main minor actinides from two or three reactors of the VVER-1000 type. A VVER-1000-type reactor can operate in a self-service mode with transmutation of its own actinides.

Neutronic study of nanofluids application to VVER-1000

Energy Technology Data Exchange (ETDEWEB)

Hadad, K., E-mail: hadad@email.arizona.ed [School of Engineering, Shiraz University, Shiraz 7134554115 (Iran, Islamic Republic of); Aerospace and Mechanical Engineering, University of Arizona, Tucson, AZ 85721 (United States); Hajizadeh, A.; Jafarpour, K. [School of Engineering, Shiraz University, Shiraz 7134554115 (Iran, Islamic Republic of); Ganapol, B.D. [Aerospace and Mechanical Engineering, University of Arizona, Tucson, AZ 85721 (United States)

2010-11-15

The change in neutronic parameters of the VVER-1000 nuclear reactor core attributable to the use of nanoparticle/water (nanofluid) as coolant is presented in this paper. Optimization of type and volume fraction of nanoparticles in water that affect the safety enhancement of core primary parameters is intended in this study. Reactivity change, radial and axial local peaking factors (LPPF), and the consequence of nanoparticle deposition on fuel clad are investigated. We considered five nanoparticles which have been studied extensively for their heat transfer properties including Alumina, Aluminum, Copper oxide, Copper and Zirconia. The results of our study show that at low concentration (0.001 volume fraction) Alumina is optimum nanoparticle for normal operation. The maximum radial and axial LPPF were found to be invariant to the type of nanofluid at low volume fractions. With an increase in nanoparticle deposition thickness on fuel clad, a flux and K{sub eff} depression occurs and Al{sub 2}O{sub 3} has the lowest rate of drop off.

The future of nuclear power

International Nuclear Information System (INIS)

Zeile, H.J.

1987-01-01

Present conditions and future prospects for the nuclear power industry in the United States are discussed. The presentation includes a review of trends in electrical production, the safety of coal as compared to nuclear generating plants, the dangers of radiation, the economics of nuclear power, the high cost of nuclear power in the United States, and the public fear of nuclear power. 20 refs

Reviewing nuclear power

International Nuclear Information System (INIS)

Robinson, Colin

1990-01-01

The UK government has proposed a review of the prospects for nuclear power as the Sizewell B pressurized water reactor project nears completion in 1994. However, a delay in the completion of Sizewell B or a change of government could put off the review for some years beyond the mid 1990s. Anticipating, though, that such a review will eventually take place, issues which it should consider are addressed. Three broad categories of possible benefit claimed for nuclear power are examined. These are that nuclear power contributes to the security of energy supply, that it provides protection against long run fossil fuel price increases and that it is a means of mitigating the greenhouse effect. Arguments are presented which cost doubt over the reality of these benefits. Even if these benefits could be demonstrated, they would have to be set against the financial, health and accident costs attendant on nuclear power. It is concluded that the case may be made that nuclear power imposes net costs on society that are not justified by the net benefits conferred. Some comments are made on how a government review, if and when it takes place, should be conducted. (UK)

Test facility for investigation of heat transfer of promising coolants for the nuclear power industry

Science.gov (United States)

Belyaev, I. A.; Sviridov, V. G.; Batenin, V. M.; Biryukov, D. A.; Nikitina, I. S.; Manchkha, S. P.; Pyatnitskaya, N. Yu.; Razuvanov, N. G.; Sviridov, E. V.

2017-11-01

The results are presented of experimental investigations into liquid metal heat transfer performed by the joint research group consisting of specialist in heat transfer and hydrodynamics from NIU MPEI and JIHT RAS. The program of experiments has been prepared considering the concept of development of the nuclear power industry in Russia. This concept calls for, in addition to extensive application of water-cooled, water-moderated (VVER-type) power reactors and BN-type sodium cooled fast reactors, development of the new generation of BREST-type reactors, fusion power reactors, and thermonuclear neutron sources. The basic coolants for these nuclear power installations will be heavy liquid metals, such as lead and lithium-lead alloy. The team of specialists from NRU MPEI and JIHT RAS commissioned a new RK-3 mercury MHD-test facility. The major components of this test facility are a unique electrical magnet constructed at Budker Nuclear Physics Institute and a pressurized liquid metal circuit. The test facility is designed for investigating upward and downward liquid metal flows in channels of various cross-sections in a transverse magnetic field. A probe procedure will be used for experimental investigation into heat transfer and hydrodynamics as well as for measuring temperature, velocity, and flow parameter fluctuations. It is generally adopted that liquid metals are the best coolants for the Tokamak reactors. However, alternative coolants should be sought for. As an alternative to liquid metal coolants, molten salts, such as fluorides of lithium and beryllium (so-called FLiBes) or fluorides of alkali metals (so-called FLiNaK) doped with uranium fluoride, can be used. That is why the team of specialists from NRU MPEI and JIHT RAS, in parallel with development of a mercury MHD test facility, is designing a test facility for simulating molten salt heat transfer and hydrodynamics. Since development of this test facility requires numerical predictions and verification

Nuclear power and modern society

International Nuclear Information System (INIS)

Komarek, A.

1999-01-01

A treatise consisting of the following sections: Development of modern society (Origin of modern society; Industrial society; The year 1968; Post-industrial society; Worldwide civic society); Historic breaks in the development of the stationary power sector (Stationary thermal power; Historic breaks in the development of nuclear power); Czech nuclear power engineering in the globalization era (Major causes of success of Czech nuclear power engineering; Future of Czech nuclear power engineering). (P.A.)

The prospect of nuclear energy in Türkiye especially after Fukushima accident

Energy Technology Data Exchange (ETDEWEB)

Şahin, Sümer, E-mail: ssahin@atilim.edu.tr [Department of Mechanical Engineering, Faculty of Engineering, ATILIM University, 06836 İncek, Gölbaşı, Ankara (Turkey)

2014-09-30

Türkiye considers since mid-50's to use nuclear electricity, but Government and bureaucracy have continuously postponed reactor construction. However, since 2010 the case has gained a real shape. Official agreement has been signed for the construction of 4 units of Russian VVER type reactors with installed power of 4×1200 MW{sub el}. It is expected that they will begin to deliver electricity early 20's. Further negotiations are being conducted with Japanese Mitsubashi and French AREVA. The target is to have nuclear electricity by 2023 at the 100{sup th} anniversary of Turkish Republic. Turkish Nuclear Energy Strategy aims; • Decrease country's dependency on foreign suppliers of energy sources • Provide fuel supply mix diversification • Utilization of environmentally friendly energy production technologies Possess advanced and prestigious power generation technologies.

Level 1 shutdown and low power operation of Mochovce NPP, Unit 1, Slovakia

International Nuclear Information System (INIS)

Halada, P.; Cillik, I.; Stojka, T.; Kuzma, M.; Prochaska, J.; Vrtik, L.

2004-01-01

The paper presents general approach, used methods and form of documentation of the results that have been applied within the shutdown and low power PSA (SPSA) study for Mochovce NPP, Unit 1, Slovakia. The SPSA project was realized by VUJE Trnava Inc., Slovakia in 2001-2002 years. The Level 1 SPSA study for Mochovce NPP Unit 1 covers internal events as well as internal (fires, floods and heavy load drop) and external (aircraft crash, extreme meteorological conditions, seismic event and influence of surrounding industry) hazards. Mochovce NPP consists of two operating units equipped with VVER 440/V213 reactors safety upgraded before construction finishing and operation start. 87 safety measures based on VVER 440 operational experience and international mission insights were implemented to enhance its operational and nuclear safety. The SPSA relates to full power PSA (FPSA) as a continuation of the effort to create a harmonized level 1 PSA model for all operational modes of the plant with the goal to use it for further purposes as follows: Real Time Risk Monitor, Maintenance Optimization, Technical Specifications Optimization, Living PSA. (author)

Experimental study of asymmetric boron dilution at VVER-1000 of Kudankulam NPP and its simulation

Energy Technology Data Exchange (ETDEWEB)

Tsyganov, Sergey V.; Kotsarev, Alexander V.; Baykov, Alexander V. [National Research Centre ' ' Kurchatov Institute' ' , Moscow (Russian Federation)

2017-09-15

The Kudankulam NPP units contain additional and unique for VVER Quick Boron Injection System (QBIS) for beyond-design-basis accident management without scram. During the physical start-up stage at hot zero power of both Kudankulam units, special tests were performed to assess the efficiency of the system. In the course of test three out of four QBIS tanks had been promptly opened and it led to the asymmetrical injection of boric acid into the core. The scenario of the tests may address to the inhomogeneous boron dilution process that is now an essential part of safety analysis of pressurised water reactors. The simulation of the process, including ex-core ion chambers readings, has been accomplished using ATHLET/BIPR-VVER code. Behaviour of some reactor parameters in the course of the test and some results of the simulation are discussing in the paper. Authors believe the process of the asymmetrical injection of boric acid may be useful for verification and validation of coupled neutronic and thermo-hydraulic codes widely used for safety analysis, including analysis of boron dilution accident.

Principal trends in ensuring safety in nuclear power plant operation in the CSSR

International Nuclear Information System (INIS)

Beranek, J.; Kriz, Z.; Kovar, P.; Macoun, J.

1984-01-01

At present two reactor units of the VVER-440 type industrial nuclear power plant are in operation in Czechoslovakia and another ten units are planned to be commissioned and put in operation by 1990. The operation of these units is carried out in compliance with licences and regulations issued by the State Regulatory Body for Nuclear Safety, a body established within the framework of the Czechoslovak Atomic Energy Commission. Operational nuclear safety assurance is based primarily on compliance with the basic safety concept as conceived in the plant design and on compliance with the requirements and terms stipulated in the course of the licensing process. On this basis, the State supervisory activity concentrates on the quality assurance of components and installations important for nuclear safety, on the quality of operating personnel and on compliance with limits and conditions for safe operation. The paper presents the main requirements stipulated in Regulation No.5 on quality assurance issued by the Czechoslovak Atomic Energy Commission and shows how the regulation is being applied. The conditions and modes of proving compliance with quality assurance programmes during plant implementation (design, fabrication, assembly, commissioning) and plant operation are described. The qualification prerequisites and capability requirements for selected categories of operating personnel as stipulated in the existing regulations are outlined. The experience accumulated by the regulatory body in preparing, examining and supervising the activity of the personnel is described. Consideration is given to the question of operational management, with the emphasis on compliance with the limits and conditions for safe operation and on the procedures for their alteration and for reporting infringements. (author)

Investigation and evaluation of erosion-corrosion status of the secondary side steam-water system at Paks Nuclear Power Plant

Energy Technology Data Exchange (ETDEWEB)

Schunk, J.; Patek, G.; Pinter, T.; Baracska Varju, I.; Doma, A.; Kovacs, A.; Nemeth, P.; Tilky, P. [Paks Nuclear Power Plant Ltd (Hungary); Osz, J. [Budapest Univ. of Science and Economy (Hungary)

2009-07-01

There were four identical VVER-440 type units installed at Paks Nuclear Power Plant with 440 MW electrical capacity of each, between 1982 and 1987. Based on inherent reserve capacity of these units, the operational and maintenance experiences and examples of power upgrading abroad it was decided to increase the power of our units in a stepwise way. Presently, this upgrading project is close to finalization resulting in 500 MW electrical capacity of each unit. To realize the planned electrical power increase it was necessary to increase the primary and secondary heat power, which requested the increase of mass flow, temperature and pressure of secondary coolant flowing through the steam generators. According to the preliminary expert evaluations these increased parameters would not cause such an increase in humidity of steam leaving the turbine houses that could adversely impair our long term power upgrading plans. The steam humidity was determined on our units and the values did not even exceed the original design values. In spite of these preliminary investigations, significant accumulation of erosion-corrosion products at different places of secondary circuit was found and erosion damages of some secondary side equipment were discovered as a probable consequence of power upgrading. An extensive evaluation programme has been started involving experts and institutes of material testing, chemistry and hydrodynamics. Results and details of that work are given in our presentation. (authors)

Status report: Nuclear fuel operating experience in implementing the program for power generation increase at VVER NPPs of JSC concern Rosenergoatom

International Nuclear Information System (INIS)

Ryabinin, Y.

2015-01-01

The power uprate program of operating WWER-1000 plants was performed by Rosenergoatom using FA-2M and FAA-PLUS for 18-month fuel cycles. Their operation was justified at 104% of the rated power, and extension to 18-month fuel cycles was carried out at WWER-1000 units (except for Kalinin NPP-1). The analysis of actual performance data confirmed the efficiency of the actions implemented, and issues addressed related to the introduction of new fuel type, extended fuel cycles and spent nuclear fuel storage and removal

Nuclear power in space

International Nuclear Information System (INIS)

Anghaie, S.

2007-01-01

The development of space nuclear power and propulsion in the United States started in 1955 with the initiation of the ROVER project. The first step in the ROVER program was the KIWI project that included the development and testing of 8 non-flyable ultrahigh temperature nuclear test reactors during 1955-1964. The KIWI project was precursor to the PHOEBUS carbon-based fuel reactor project that resulted in ground testing of three high power reactors during 1965-1968 with the last reactor operated at 4,100 MW. During the same time period a parallel program was pursued to develop a nuclear thermal rocket based on cermet fuel technology. The third component of the ROVER program was the Nuclear Engine for Rocket Vehicle Applications (NERVA) that was initiated in 1961 with the primary goal of designing the first generation of nuclear rocket engine based on the KIWI project experience. The fourth component of the ROVER program was the Reactor In-Flight Test (RIFT) project that was intended to design, fabricate, and flight test a NERVA powered upper stage engine for the Saturn-class lunch vehicle. During the ROVER program era, the Unites States ventured in a comprehensive space nuclear program that included design and testing of several compact reactors and space suitable power conversion systems, and the development of a few light weight heat rejection systems. Contrary to its sister ROVER program, the space nuclear power program resulted in the first ever deployment and in-space operation of the nuclear powered SNAP-10A in 1965. The USSR space nuclear program started in early 70's and resulted in deployment of two 6 kWe TOPAZ reactors into space and ground testing of the prototype of a relatively small nuclear rocket engine in 1984. The US ambition for the development and deployment of space nuclear powered systems was resurrected in mid 1980's and intermittently continued to date with the initiation of several research programs that included the SP-100, Space Exploration

VVANTAGE 6 - an advanced fuel assembly design for VVER reactors

International Nuclear Information System (INIS)

Doshi, P.K.; DeMario, E.E.; Knott, R.P.

1993-01-01

Over the last 25 years, Westinghouse fuel assemblies for pressurized water reactors (PWR's) have undergone significant changes to the current VANTAGE 5. VANTAGE 5 PWR fuel includes features such as removable top nozzles, debris filter bottom nozzles, low-pressure-drop zircaloy grids, zircaloy intermediate flow mixing grids, optimized fuel rods, in-fuel burnable absorbers, and increased burnup capability to region average values of 48000 MWD/MTU. These features have now been adopted to the VVER reactors. Westinghouse has completed conceptual designs for an advanced fuel assembly and other core components for VVER-1000 reactors known as VANTAGE 6. This report describes the VVANTAGE 6 fuel assembly design

Role of nuclear power

International Nuclear Information System (INIS)

Eklund, S.

1982-01-01

A survey of world nuclear installations, the operating experiences of power reactors, and estimates of future nuclear growth leads to the conclusion that nuclear power's share of world electric power supply will grow slowly, but steadily during this decade. This growth will lead advanced countries to use the commercial breeder by the end of the century. Nuclear power is economically viable for most industrialized and many developing countries if public acceptance problems can be resolved. A restructuring of operational safety and regulations must occur first, as well as a resolution of the safeguards and technology transfer issue. 7 figures, 7 tables

Role and position of Nuclear Power Plants Research Institute in nuclear power industry

International Nuclear Information System (INIS)

Metke, E.

1984-01-01

The Nuclear Power Plants Research Institute carries out applied and experimental research of the operating states of nuclear power plants, of new methods of surveillance and diagnosis of technical equipment, it prepares training of personnel, carries out tests, engineering and technical consultancy and the research of automated control systems. The main research programme of the Institute is the rationalization of raising the safety and operating reliability of WWER nuclear power plants. The Institute is also concerned with quality assurance of selected equipment of nuclear power plants and assembly works, with radioactive waste disposal and the decommissioning of nuclear power plants as well as with the preparation and implementation of the nuclear power plant start-up. The Research Institute is developing various types of equipment, such as equipment for the decontamination of the primary part of the steam generator, a continuous analyzer of chloride levels in water, a gas monitoring instrument, etc. The prospects are listed of the Research Institute and its cooperation with other CMEA member countries. (M.D.)

Nuclear fuel for VVER reactors. Actual state and trends

International Nuclear Information System (INIS)

Molchanov, V.

2009-01-01

The implementation of 2nd generation of FA with the following performance characteristics: 1) Average FP failure factor during operation is less than 1x10 -6 ; 2) Fuel burn-up: up to 60 GWxd/tHM; 3) 5-year fuel cycle; 4) Unit thermal power uprate up to 110% N nom ; 5) Load Follow Mode (97,5±2,5% and 100-75-100% N nom ) is presented. A new generation of FA (TVSA and TVS-2) is developed, implemented and successfully operated at Russian, Ukrainian and Bulgarian NPPs providing: Safe and reliable operation cycle of 6 years; Assembly burn-up - up to 60 GWxd/tHM; Load Follow Mode. For satisfaction of customer needs regarding nuclear fuel performance the following development of FA design is under way: Power uprate up to 104% N nom and Fuel cycles length up to 18 months

Thermal aging effects of VVER-1000 weld metal under operation temperature

International Nuclear Information System (INIS)

Chernobaeva, A.A.; Kuleshova, E.A.; Gurovich, B.A.; Erak, D.Y.; Zabusov, O.O.; Maltsev, D.A.; Zhurko, D.A.; Papina, V.B.; Skundin, M.A.

2015-01-01

The VVER-1000 thermal aging surveillance specimen sets are located in the reactor pressure vessel (RPV) under real operation conditions. Thermal aging surveillance specimens data are the most reliable source of the information about changing of VVER-1000 RPV materials properties because of long-term (hundred thousand hours) exposure at operation temperature. A revision of database of VVER-1000 weld metal thermal aging surveillance specimens has been done. The reassessment of transition temperature (T t ) for all tested groups of specimens has been performed. The duration of thermal exposure and phosphorus contents have been defined more precisely. The analysis of thermal aging effects has been done. The yield strength data, study of carbides evolution show absence of hardening effects due to thermal aging under 310-320 C degrees. Measurements of phosphorus content in grain boundaries segregation in different states have been performed. The correlation between intergranular fracture mode in Charpy specimens and transition temperature shift under thermal aging at temperature 310-320 C degrees has been revealed. All these data allow developing the model of thermal aging. (authors)

Design and implementation of the control system for nuclear plant VVER-1000. Instrumentation (program technical complexes)

International Nuclear Information System (INIS)

Siora, A.; Tokarev, V.; Bakhmach, E.

2004-01-01

Program-technical complexes (PTC) are designed as control and protection systems in water-moderated atomic reactors, including emergency and preventive systems, automatic control, unloading, reactor capacity limitation and accelerated preventive protection systems. Utilization of programmable logic integrated circuits from world leading manufacturers makes the complexes simple in structure, compact, with low energy demands and mutually independent for key and supporting functions The results of PTC assessment and implementation in Ukraine are outlined. Opportunities for a future development of RADIJ company in the area of control and protection systems for VVER reactors are also discussed

Banning nuclear power at sea

International Nuclear Information System (INIS)

Handler, J.

1993-01-01

This article argues that now that the East-West conflict is over, nuclear-powered vessels should be retired. Nuclear-powered ships and submarines lack military missions, are expensive to build and operate, generate large amounts of long-lived deadly nuclear waste from their normal operations and when they are decommissioned, and are subject to accidents or deliberate attack which can result in the sinking of nuclear reactors and the release of radiation. With the costs of nuclear-powered vessels mounting, the time has come to ban nuclear power at sea. (author)

The need for nuclear power

International Nuclear Information System (INIS)

1977-12-01

This leaflet examines our energy future and concludes that nuclear power is an essential part of it. The leaflet also discusses relative costs, but it does not deal with social and environmental implications of nuclear power in any detail, since these are covered by other British Nuclear Forum publications. Headings are: present consumption; how will this change in future; primary energy resources (fossil fuels; renewable resources; nuclear); energy savings; availability of fossil fuels; availability of renewable energy resources; the contribution of thermal nuclear power; electricity; costs for nuclear power. (U.K.)

Nuclear power statistics 1985

International Nuclear Information System (INIS)

Oelgaard, P.L.

1986-06-01

In this report an attempt is made to collect literature data on nuclear power production and to present it on graphical form. Data is given not only for 1985, but for a number of years so that the trends in the development of nuclear power can be seen. The global capacity of nuclear power plants in operation and those in operation, under construction, or on order is considered. Further the average capacity factor for nuclear plants of a specific type and for various geographical areas is given. The contribution of nuclear power to the total electricity production is considered for a number of countries and areas. Finally, the accumulated years of commercial operation for the various reactor types up to the end of 1985 is presented. (author)

Nuclear power economics

International Nuclear Information System (INIS)

Moynet, G.

1987-01-01

The economical comparison of nuclear power plants with coal-fired plants in some countries or areas are analyzed. It is not difficult to show that nuclear power will have a significant and expanding role to play in providing economic electricity in the coming decades. (Liu)

Energy policy and nuclear power. Expectations of the power industry

International Nuclear Information System (INIS)

Harig, H.D.

1995-01-01

In the opinion of the power industry, using nuclear power in Germany is a responsible attitude, while opting out of nuclear power is not. Electricity utilities will build new nuclear power plants only if the structural economic and ecological advantages of nuclear power are preserved and can be exploited in Germany. The power industry will assume responsibility for new complex, capital-intensive nuclear plants only if a broad societal consensus about this policy can be reached in this country. The power industry expects that the present squandering of nuclear power resources in Germany will be stopped. The power industry is prepared to contribute to finding a speedy consensus in energy policy, which would leave open all decisions which must not be taken today, and which would not constrain the freedom of decision of coming generations. The electricity utilities remain committed proponents of nuclear power. However, what they sell to their customers is electricity, not nuclear power. (orig.) [de

Safeguards Practices and Future Challenges for Peaceful Use of Nuclear Energy in Bangladesh

International Nuclear Information System (INIS)

Islam, M.S.; Chowdhury, M.D.A.; Kibria, A.F.; Alam, H.B.

2015-01-01

Nuclear material and different category of radiation sources are being used in industries, R&D & education purposes. All of them are used for human welfare and economic uplift of the country. Prior to use, Bangladesh has firmly committed for the peaceful use of nuclear energy in a safe, secured and non-proliferation manner. Bangladesh has regularly provided credible assurance about the non-diversion of nuclear material as well as the absence of undeclared material and activities to the international community by fulfiling the obligations under the NPT and Comprehensive Safeguards Agreements (CSA) over the last 35 years. IAEA approved the State Level Safeguards Approach (SLA) for Bangladesh on 1 December, 2006 and consequently Bangladesh entered into the Integrated Safeguards (IS) regime on 1 January, 2007. The Government of Bangladesh enacted a comprehensive nuclear law titled ''Bangladesh Atomic Energy Regulatory (BAER) Act-2012'' and under this act established ''Bangladesh Atomic Energy Regulatory Authority (BAERA)'' in February 2013 to regulate all nuclear activities and to fulfil its international obligations. Furthermore, Bangladesh has signed agreements with Russia for setting up two 1000 MWe generation-III VVER type power reactors. During the INIR missions conducted by IAEA, the team identified some gaps and then recommended to develop, implement and to enforce of safeguards framework including strengthening the SSAC's oversight capability embarking the first nuclear power program in the country. Bangladesh is working on legal and regulatory requirements in adopting the VVER technology into the BAER Act-2012 related to safeguards. The purpose of this paper is to present an overview of country's practices in implementing the IAEA safeguards and also to provide with an in-depth look at the legislations, regulations and facility procedures for strengthening the safeguards infrastructure and to identify future

The ethical justification of nuclear power

International Nuclear Information System (INIS)

Van Wyk, J.H.

1985-01-01

This study pamphlet deals with the questions of ethics, nuclear power and the ethical justification of nuclear power. Nuclear power is not only used for warfare but also in a peaceful way. Ethical questions deal with the use of nuclear weapons. Firstly, a broad discussion of the different types of ethics is given. Secondly, the peaceful uses of nuclear power, such as nuclear power plants, are discussed. In the last place the application of nuclear power in warfare and its disadvantages are discussed. The author came to the conclusion that the use of nuclear power in warfare is in contrary with all Christian ethics

Dictionary of nuclear power

International Nuclear Information System (INIS)

Koelzer, W.

2012-06-01

The actualized version (June 2012) of the dictionary on nuclear power includes all actualizations and new inputs since the last version of 2001. The original publication dates from 1980. The dictionary includes definitions, terms, measuring units and helpful information on the actual knowledge concerning nuclear power, nuclear fuel cycle, nuclear facilities, radioactive waste management, nuclear physics, reactor physics, isotope production, biological radiation effects, and radiation protection.

Italian nuclear power industry after nuclear power moratorium: Current state and future prospects

International Nuclear Information System (INIS)

Adinolfi, R.; Previti, G.

1992-01-01

Following Italy's nuclear power referendum results and their interpretation, all construction and operation activities in the field of nuclear power were suspended by a political decision with consequent heavy impacts on Italian industry. Nevertheless, a 'nuclear presidium' has been maintained, thanks to the fundamental contribution of activities abroad, succeeding in retaining national know-how and developing the new technologies called for the new generation of nuclear power plants equipped with intrinsic and/or passive reactor safety systems

Accounting for the inertia of the thermocouples' measurements by modelling of a NPP Kalinin-3 transient with the coupled system code ATHLET-BIPR-VVER

International Nuclear Information System (INIS)

Nikonov, S.; Velkov, K.

2008-01-01

The ATHLET-BIPR-VVER coupled system code is applied for performing of safety analysis for different WWER reactors. During the last years its validation matrix is continuously being enlarged. The measurements performed during the commissioning phase of NPP Kalinin Unit 3 for the transient 'Switching-off of one Main Circulation Pump at nominal power' are very well documented and have a variety of recorded integral and local thermo-hydraulic and neutron-physic parameters including the measurements' errors. This data is being used for further validation of the coupled code system ATHLET-BIPR-VVER. In the paper are discussed the problems and our solutions by the correct interpretation of the measured thermocouples' records at NPP Kalinin-3 and the comparison with the predicted results by the coupled thermal-hydraulic/neutron-kinetic code ATHLET-BIPR-VVER. Of primary importance by such comparisons is the correct accounting of the fluid mixing process that take place in the surrounding of the measuring sensors and also the consideration of the time delay (inertia term) of the measuring devices. On the bases of previous experience and many simulations of the defined transient a method is discussed and proposed to consider correctly the inertia term of the thermocouples' measurements. The new modelling is implemented in the coupled system code ATHLET-BIPR-VVER for further validation. (Author)

Nuclear power in Pakistan

International Nuclear Information System (INIS)

Siddiqui, Z.H.; Qureshi, I.H.

2005-01-01

Pakistan started its nuclear power program by installing a 137 M We Canadian Deuterium Reactor (Candu) at Karachi in 1971 which became operational in 1972. The post-contract technical support for the Karachi Nuclear Power Plant (KANUPP) was withdrawn by Canada in 196 as a consequence of Indian nuclear device test in 1974. In spite of various difficulties PAEC resolved to continue to operate KANUPP and started a process for the indigenous fabrication of spare parts and nuclear fuel. The first fuel bundle fabricated in Pakistan was loaded in the core in 1980. Since then KANUPP has been operating on the indigenously fabricated fuel. The plant computer systems and the most critical instrumentation and Control system were also replaced with up-to date technology. In 2002 KANUPP completed its original design life of 30 year. A program for the life extension of the plant had already been started. The second nuclear power plant of 300 M We pressurized water reactor purchased from China was installed in Chashma in 1997, which started commercial operations in 2001. Another unit of 300 M We will be installed at Chashma in near future. These nuclear power plants have been operating under IAEA safeguards agreements. PAEC through the long-term performance of the two power plants has demonstrated its competence to safely and successfully operate and maintain nuclear power plants. Pakistan foresees an increasingly important and significant share of nuclear power in the energy sector. The Government has recently allocated a share of 8000 MWe for nuclear energy in the total energy scenario of Pakistan by the year 2025. (author)

Nuclear power and the nuclear fuel cycle

International Nuclear Information System (INIS)

1988-06-01

The percentage of electricity generated by nuclear energy in each of the 26 countries that operated nuclear power plants in 1987 is given. The current policy and programs of some of these countries is described. News concerning uranium mining, enrichment, reprocessing and waste management is also included. Data in the form of a generalized status summary for all power reactors (> 30 MWEN) prepared from the nuclear power reactor data files of ANSTO is shown

Without nuclear power

International Nuclear Information System (INIS)

1987-01-01

The arguments put forward by the SPD point to the following: Backing out of nuclear power is a must, because of the awful quality of the hazards involved; because there can be no real separation guaranteed between civil and military utilisation of nuclear energy; for reasons of international responsibility; because we must not pass the buck on to the next generation; because social compatibility must be achieved; because the story of the 'cheap' nuclear generation of electricity is a fairy tale; because nuclear power pushes back coal as an energy source; because current ecological conditions call for abandonment of nuclear power, and economic arguments do not really contradict them. A reform of our energy system has to fulfill four requirements: Conserve energy; reduce and avoid environmental pollution; use renewable energy sources as the main sources; leave to the next generation the chance of choosing their own way of life. (HSCH) [de

Mobile nuclear power systems

International Nuclear Information System (INIS)

Andersson, B.

1988-11-01

This report is meant to present a general survey of the mobile nuclear power systems and not a detailed review of their technical accomplishments. It is based in published material mainly up to 1987. Mobile nuclear power systems are of two fundamentally different kinds: nuclear reactors and isotopic generators. In the reactors the energy comes from nuclear fission and in the isotopic generators from the radioactive decay of suitable isotopes. The reactors are primarily used as power sourves on board nuclear submarines and other warships but have also been used in the space and in remote places. Their thermal power has ranged from 30 kWth (in a satellite) to 175 MWth (on board an aircraft carrier). Isotopic generators are suitable only for small power demands and have been used on board satellites and spaceprobes, automatic weatherstations, lighthouses and marine installations for navigation and observation. (author)

Nuclear power in Asia

International Nuclear Information System (INIS)

2007-01-01

The Australian Uranium Association reports that Asia is the only region in the world where electricity generating capacity and specifically nuclear power is growing significantly. In East and South Asia, there are over 109 nuclear power reactors in operation, 18 under construction and plans to build about a further 100. The greatest growth in nuclear generation is expected in China, Japan, South Korea and India. As a member of the SE Asian community, Australia cannot afford to ignore the existence and growth of nuclear power generation on its door step, even if it has not, up to now, needed to utilise this power source

Numerical Boron mixing studies for Loviisa Nuclear Power Plant

Energy Technology Data Exchange (ETDEWEB)

Gango, P. [IVO International Ltd. (Finland)

1995-09-01

A program has been started for studying numerically boron mixing in the downcomer of Loviisa NPP (VVER-440). Mixing during the transport of a diluted slug from the loop to the core might serve as an inherent protection mechanism against severe reactivity accidents in inhomogenous boron dilution scenarios for PWRs. The commercial general purpose Computational Fluid Dynamics (CFD) core PHOENICS is used for solving the governing fluid flow equations in the downcomer geometry of VVER-440. So far numerical analyses have been performed for steady state operation conditions and two different pump driven transients. The steady state analyses focused on model development and validation against existing experimental data. The two pump driven transient scenarios reported are based on slug transport during the start of the sixth and first loop respectively. The results from the two transients show that mixing is case and plant specific; the high and open downcomer geometry of VVER-440 seems to be advantageous from mixing point of view. In addition the analyzing work for the {open_quotes}first pump start{close_quotes} scenario brought up some considerations about flow distribution in the existing experimental facilities.

Nuclear power