scholarly journals TO CALCULATION OF ELLIPTIC CRUSHER WITH FORM MEMORY EFFECT

2020 ◽  
Vol 2020 (7) ◽  
pp. 12-19
Author(s):  
Sergey Shishkin
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Calculation Model ◽  
Design Calculation ◽  
Round Cross Section ◽  
Rock Destruction ◽  
Essential Condition ◽  
Field Development ◽  
Power Characteristics ◽  
Definition Of

The investigation purpose consists in the development of a calculation model of a thermo-mechanical power device intended for destruction of concrete structures and hard mineral rock. Its operation principle is based on the transformation of the initial round cross-section into the oval one during realization of alloy form memory that ensures a wedging effect. There is offered the solution of the problem on linear effort definition of a crusher at its impact upon well sides depending on rock resistance and capacity of thermo-mechanical return. The investigation method consists in the modeling of a power pipe with the cylindrical shell at its non-axisymmetric loading as a deformation-power analogue of which a thermo-mechanical diagram is accepted. The essential condition of such an approach is the identity of a task and deformation restoration with samples at the diagram formation and a power element in the structure. Thereupon fundamentally new is a calculation definition of the parameters of reactive stress dependence upon the deformation value of under-restoration at radial bending according to the diagram at the specified deformation by stretching that allows excluding a labor-intensive experiment. As a result of the investigations there are obtained formulae for the definition of a linear effort and also for the computation of pipe dimensions within the limits of design calculation. There is shown an actual example of power characteristics definition. The calculation reliability is confirmed with the application of these power devices during radioactive concrete structure destruction at one of nuclear power plants and at hard rock destruction at emerald field development. In such a way, the thermo-mechanical crusher design offered and a corresponding procedure for calculations can be used in practice without any changes.

Implementation of an Approach for Characterisation of Radiological Inventory for Decommissioning at Chinon A2 NPP

2014 ◽  
Author(s):  
A. Traichel ◽  
F. Tardy ◽  
M. Mummert
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Statistical Processing ◽  
Analysis Data ◽  
Measured Data ◽  
Primary Circuit ◽  
Measurement Systems ◽  
Definition Of ◽  
Local Sampling

A general overview of the existing radioactive inventory in the plant is necessary for the decommissioning of nuclear power plants. Based on the knowledge about radiological inventory, appropriate decommissioning techniques and procedures can be specifically used. In order to derive the existing radiological activity in the facility a study was carried out to obtain a representative overview of the total radiological situation at the NPP. Within a study a generic methodology for the radiological characterization was developed. This methodology has been applied on the CO2-circuit of the gas-cooled, graphite-moderated reactor Chinon A2 (MAGNOX type). This paper covers the implementation of an approach for characterisation of radiological inventory for decommissioning. The approach aims at the definition of the number and distribution of local sampling, required measurements as well as suitable measurement systems leading to a confident result with minimized effort in sampling. The paper covers two main objectives: 1. Methodology at and 2. Determination of radiological inventory based on measured data. The proposed methodology is a stepwise procedure which offers the possibility for minimizing the number of required measurements/sample analyses. At the first step the underlying system is an “as-simple-as-possible”-example with homogeneous contamination. In a second step the methodology is expanded to a more realistic and complex system, for which additional investigations have to be performed. The determination of the radiological inventory using the methodology has to consider a given confidence level and maximum allowed error. Therefore statistical assessment is widely used in estimations. The result of this first part of study generates the basis for further investigation. This comprises application of methodology to the mentioned technical system. Therefore corresponding measurement and analysis data have to be delivered and proven regarding adequacy for the proposed methodology. From the dataset various measurement systematic and retained parameters could be derived. The accuracy of given measured data was checked by further examination. The result of the performed analysis leads to a statement about the activity in the primary circuit. The result of this study is an comprehensive estimation of the activity by defined statistical processing of analysed data. The result consists moreover of the analysis of the measurement plan and of distribution and deviation within the measured data. Suggestions for further measurement campaigns are provided based on the deviations and inconsistencies of the data. With the help of these suggestions it should be possible to decrease the number of samples and measuring data as well as improve the comparability of separate measurement processes. Particular potential for improvement of the result for inventory can be seen in a deeper analysis of uncertainties, this was realised and will be explained in the paper.

scholarly journals Safety of Nuclear Power Plants with Respect to the Fault Displacement Hazard

2020 ◽  
Vol 10 (10) ◽  
pp. 3624
Author(s):  
Tamás János Katona
Keyword(s):  
Seismic Design ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Ground Displacement ◽  
Design Basis ◽  
Hazard Level ◽  
Definition Of ◽  
Fault Displacement ◽  
Probabilistic Criteria

The hazard of permanent ground displacements/deformations can challenge the safety of the nuclear power plants. Increasing knowledge of the hazard and development of methods for structure–fault–displacement interaction motivates the designing of nuclear power plants for permanent ground displacement instead of abandoning the sites that could be affected by this kind of hazard. For the design basis, permanent ground displacement should be defined at the hazard level that complies with the probabilistic criteria for accounting for the natural hazards in the design that also ensure compliance with probabilistic safety criteria. In this paper, a procedure is proposed for the definition of the design basis permanent ground displacement that is based on the deaggregation of seismic design basis hazard. The definition of the displacement for the margin evaluation is also proposed. The feasibility of safe design is also demonstrated for the proposed definition of design basis hazard via qualitative judgement on the sensitivity of the structures, systems and components ensuring the fundamental safety functions with respect to the permanent ground displacement that is supported by existing case studies.

scholarly journals Applicability of Pseudoprobabilistic Method of Liquefaction Hazard Assessment for Nuclear Power Plants at Diffuse Seismicity Sites

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Tamás János Katona ◽  
Erzsébet Győri ◽  
László Tóth
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Liquefaction Hazard ◽  
Engineering Measures ◽  
Definition Of ◽  
Safety Considerations ◽  
Hazard Levels ◽  
Diffuse Seismicity

For the new nuclear power plants, the hazard of liquefaction due to earthquakes should be excluded by appropriate site selection or eliminated by engineering measures. An important question is how to define a quantitative criterion for negligibility of the liquefaction hazard. In the case of operating plants, liquefaction can be revealed as a beyond-design-basis event. It is important to learn whether the liquefaction hazard has a safety relevance and whether there is a sufficient margin to the onset of liquefaction. The use of pseudoprobabilistic method would be practicable for the definition of probability of liquefaction, but it could result in overconservative results. In this paper, the applicability of the pseudoprobabilistic procedure is demonstrated for the sites in diffuse seismicity environment and for low hazard levels that are typical for nuclear safety considerations. Use of the procedure is demonstrated in a case study with realistic site-plant parameters.

External Extreme Impacts on NPP Constructions – Methodology of Computational Simulation

2014 ◽  
Vol 1040 ◽  
pp. 472-477
Author(s):  
Alexandr M. Belostotskiy ◽  
Sergey I. Dubinsky ◽  
Irina N. Afanasyeva ◽  
Fedor M. Kotov ◽  
Vladislav V. Vershinin ◽  
...  
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Computational Simulation ◽  
Software Application ◽  
Methods Of Analysis ◽  
Advanced Analysis ◽  
Definition Of ◽  
The Impact ◽  
External Loads

In accordance with results of analysis of state-of-the-art theoretical and experimental research works, analysis and synthesis of data on the impact of extreme impacts on structures of existing nuclear power plants (including NPP "Fukushima-1", Japan), and other unique objects, the existing regulations, corresponding design codes and procedures do not fully take into account the specific definition of extreme (special) external loads and impacts on the main building of NPP, and, therefore, require clarification and development. The distinctive paper is devoted to advanced methods of analysis, choice of appropriate and correct methods and software application packages for numerical simulation of external loads and impacts on the basic structures of nuclear power plants (wind hurricane, tornado, plane crash, the impact of the shock wave, seismic and tsunami effect). Results of development, adaptation and verification (with the use of universal software application packages) within representative number of sample problems, dealing with advanced methods of analysis, definition of loads and impacts on the basic structures of nuclear power plants are presented. The results of analysis showed correctness and effectiveness of the developed numerical methods of advanced analysis and definition of extreme external loads and impacts on NPP structures of a new generation.

Analysis of Emergency Staffing for Nuclear Power Plants

1983 ◽  
Vol 27 (2) ◽  
pp. 184-186
Author(s):  
Michael K. Lindell
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Phase Method ◽  
Situational Analysis ◽  
Limited Information ◽  
Staffing Levels ◽  
Definition Of ◽  
Staffing Requirements ◽  
Analysis Determination

Determination of staffing requirements for response to nuclear plant emergencies should be based upon task analysis in order to ensure that emergency functions can be performed in any type of accident. The method of analysis must recognize the differences between personnel performance in normal and emergency conditions and the limited information available for analysis of emergency tasks. A four-phase method is described that consists of generic analysis (identification of general emergency functions and tasks), situational analysis (definition of the characteristics of the classes of emergencies that can occur), quantitative analysis (determination of workloads, by position) and sensitivity analysis (examination of the degree to which changes in assumptions produce changes in required staffing levels).

AVAILABILITY OF AN INTERMITTENTLY REQUIRED SYSTEM: APPLICATION TO A FOSSIL FUEL POWER PLANT

2001 ◽  
Vol 08 (03) ◽  
pp. 259-269
Author(s):  
MARC BOUISSOU ◽  
YANNICK LEFEBVRE
Keyword(s):  
Mathematical Method ◽  
Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Fossil Fuel ◽  
Electricity Consumption ◽  
Production Loss ◽  
Fossil Fuel Power Plant ◽  
Definition Of ◽  
Fossil Fuel Power Plants

Electricité de France produces about 75% of its electricity with nuclear power plants. Some hydraulic plants and most fossil fuel power plants are used to pass electricity consumption peaks. Therefore these facilities are required only intermittently. For such systems, a breakdown does not result in a production loss during a standby period. This particular feature is not taken into account by conventional availability evaluation methods. The objective of this paper is to introduce a definition of availability which holds in such a context, and to describe a mathematical method suited to the calculation of this new definition of availability.

scholarly journals Safety Assessment of Nuclear Power Plants for Liquefaction Consequences

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Tamás János Katona ◽  
Zoltán Bán ◽  
Erzsébet Győri ◽  
László Tóth ◽  
András Mahler
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Soft Soil ◽  
Practical Importance ◽  
Point Of View ◽  
Liquefaction Susceptibility ◽  
Accident Management ◽  
Definition Of ◽  
Soil Behaviour

In case of some nuclear power plants constructed at the soft soil sites, liquefaction should be analysed as beyond design basis hazard. The aim of the analysis is to define the postevent condition of the plant, definition of plant vulnerabilities, and identification of the necessary measures for accident management. In the paper, the methodology of the analysis of liquefaction effects for nuclear power plants is outlined. The procedure includes identification of the scope of the safety analysis and the acceptable limit cases for plant structures having different role from accident management point of view. Considerations are made for identification of dominating effects of liquefaction. The possibility of the decoupling of the analysis of liquefaction effects from the analysis of vibratory ground motion is discussed. It is shown in the paper that the practicable empirical methods for definition of liquefaction susceptibility provide rather controversial results. Selection of method for assessment of soil behaviour that affects the integrity of structures requires specific considerations. The case of nuclear power plant at Paks, Hungary, is used as an example for demonstration of practical importance of the presented results and considerations.

scholarly journals Methods of improvement of forecasting of development of mineral deposits' power supply

10.30544/129 ◽  
2015 ◽  
Vol 21 (1) ◽  
pp. 15-24
Author(s):  
Alexander V. Putilov ◽  
Alexander G. Vorobev ◽  
Dmitriy V. Timokhin ◽  
Marina V. Bugaenko ◽  
Galina I. Popova
Keyword(s):  
Power Supply ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Cash Flows ◽  
Mineral Deposits ◽  
Cross Model ◽  
Energy Technologies ◽  
Economic Methods ◽  
Definition Of

Mineral deposits (among which non-ferrous metals take a leading place) are situated on the territory of our planet rather unevenly, and often in out-of-the-way places. Nuclear power (particularly, transportable nuclear power plants) provides the new possibilities of power supply, which is very important for deposits' development. This article shares the economic aspects of forecasting in the field of power development (in particular, nuclear power on the basis of transportable nuclear power plants). Economic barriers of development of innovative nuclear technologies are considered on the example of transportable nuclear power plants. At the same time, there are given the ways of elimination of such barrier to development of this technology as methodical absence of investigation of a question of distribution of added cost between producers of innovative equipment and final product. Addition of new analytical tool (“business diagonal”) is offered for a method of definition of economically efficient distribution of added cost (received as a result of introduction of innovative technologies) between participants of production and consumption of atomic energy within the “economic cross” model. There is offered the order of use of method of cash flows discounting at calculations between nuclear market participants. Economic methods, offered in this article, may be used in forecasting of development of other energy technologies and introduction of prospective energy equipment.

Industrial Application of Research Results of Packings on Safety Relevant Valves in Nuclear Power Plants

2006 ◽  
Author(s):  
Reinhard Koring
Keyword(s):  
Industrial Application ◽  
Nuclear Power ◽  
Power Plants ◽  
Design Calculation ◽  
Detailed Calculation ◽  
Research Results ◽  
Packing Rings ◽  
Leak Tightness ◽  
Specific Material ◽  
Packing Assembly

In a NPP approximately 380 safety relevant valves are installed. The main requirements are the safety and operational availability as well as a adequate leak tightness of the sealings and stem packings. Based upon the research results of the MPA-Stuttgart, Germany on packing features specific procedures for handling, assembly and maintenance of packings and analytical inputs for the design calculation have been developed. Depending on the valve size, especially on the stem diameter, the packing influences the necessary stem force for the closing and opening function due to the amount of friction force. The complying equations of the valve calculation guideline were derived from the research results and rely on covering material characteristics of the approved packing rings such as friction coefficient and the vertical/horizontal force transfer factor of the stressing force. The industrial application often requires a more detailed calculation and handling of the actually installed packing configurations especially if existing valves are considered for redesign measures and recalculation. Therefore additionally mock-up tests of existing packing configurations have been performed in cooperation with the packing manufacturer in order to get very specific material coefficients as input data for the calculations. This paper presents the application of research results to design calculation of safety relevant valves as well as the development of procedures for the packing assembly and maintenance.

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