Engineering and design of fast reactors

1990 ◽  
Vol 331 (1619) ◽  
pp. 301-312 ◽  
Keyword(s):  
Fast Neutrons ◽  
Large Temperature ◽  
Steam Generators ◽  
The Core ◽  
Mode Of Operation ◽  
Protection Systems ◽  
Core Components ◽  
Main Components ◽  
System Layout ◽  
Coolant System

The paper deals with the basic engineering aspects specific to a fast breeder reactor. The characteristic design features are mainly determined by the coolant being sodium and the fast neutrons in the core. Some particular properties of sodium, the high temperature and the large temperature differences impose severe requirements on materials and structures. Also the mode of operation, the protection systems and the auxiliary systems are strongly influenced by these conditions. The resulting engineering implications will be illustrated by describing, firstly, the core layout and the core components, secondly, the main coolant system layout and its auxiliaries and, thirdly, the design aspects of main components such as pumps, heat exchangers and steam generators.

scholarly journals Feasibility of Natural Circulation Heat Transport in the ENHS

2002 ◽  
Author(s):  
James J. Sienicki
Keyword(s):  
Heat Exchange ◽  
Natural Circulation ◽  
Gas Injection ◽  
Wall Friction ◽  
Steam Generators ◽  
Primary Coolant ◽  
The Core ◽  
Nuclear Heat ◽  
System Temperature ◽  
Coolant System

An analysis has been carried out of natural circulation thermal hydraulics in both the primary and intermediate circuits of the Encapsulated Nuclear Heat Source (ENHS). It is established that natural circulation enhanced by gas injection into the primary coolant above the core, or the intermediate coolant above the heat exchange zone, is effective in transporting the nominal core power to the steam generators without the attainment of excessive system temperatures. Uncertainties in thermophysical properties and wall friction have a relatively small effect upon the calculated best estimate primary and intermediate coolant system temperature rises.

scholarly journals The core components of education 4.0 in higher education: Three case studies in engineering education

2021 ◽  
Vol 93 ◽  
pp. 107278
Author(s):  
Jhonattan Miranda ◽  
Christelle Navarrete ◽  
Julieta Noguez ◽  
José-Martin Molina-Espinosa ◽  
María-Soledad Ramírez-Montoya ◽  
...  
Keyword(s):  
Higher Education ◽  
Engineering Education ◽  
Case Studies ◽  
The Core ◽  
Core Components

Semantic Desktop for the End-UserSemantic Desktop für Anwender

i-com ◽  
2009 ◽  
Vol 8 (3) ◽  
pp. 25-32 ◽  
Author(s):  
Gunnar Aastrand Grimnes ◽  
Benjamin Adrian ◽  
Sven Schwarz ◽  
Heiko Maus ◽  
Kinga Schumacher ◽  
...  
Keyword(s):  
Knowledge Management ◽  
Knowledge Work ◽  
Personal Knowledge ◽  
Term Study ◽  
The Core ◽  
Personal Knowledge Management ◽  
Long Term Study ◽  
Core Components

AbstractThis article describes the Semantic Desktop. We give insights into the core services that aim to improve personal knowledge management on the desktop. We describe these core components of our Semantic Desktop system and give evaluation results. Results of a long-term study reveal effects of using the Semantic Desktop on personal knowledge work.

The Design of ZigBee Wireless Network for the Detection Platform of the Cylinders

2012 ◽  
Vol 241-244 ◽  
pp. 2504-2509
Author(s):  
Yan Li ◽  
Qiao Xiang Gu
Keyword(s):  
Real Time ◽  
Wireless Network ◽  
Environmental Conditions ◽  
Protocol Stack ◽  
The Real ◽  
The Core ◽  
Core Components ◽  
Real Time Detection ◽  
Cable Connection

The equipment, called detection platform of the cylinders, is used for detecting cylinders so that cylinders can be at ease use. In order to transmit the real-time detection data to PC for further processing, the platform should be connected with PC. Cable connection, in some production and environmental conditions, is limited. Under the circumstance, building wireless network is the better choice. Through comparative studying, ZigBee is chosen to be the technology for building wireless network. ZigBee chip and ZigBee2006 protocol stack are the core components in the ZigBee nodes.

scholarly journals The Activity of Lipid A and Core Components of Bacterial Lipopolysaccharides in the Prevention of the Hypersensitive Response in Pepper

1997 ◽  
Vol 10 (7) ◽  
pp. 926-928 ◽  
Author(s):  
Mari-Anne Newman ◽  
Michael J. Daniels ◽  
J. Maxwell Dow
Keyword(s):  
Hypersensitive Response ◽  
Xanthomonas Campestris ◽  
Lipid A ◽  
Enteric Bacteria ◽  
Core Oligosaccharide ◽  
The Core ◽  
Minimal Structure ◽  
Core Components ◽  
Pre Treatment ◽  
Bacterial Lipopolysaccharides

Pre-treatment of leaves of pepper (Capsicum annuum) with lipopolysaccharide (LPS) preparations from enteric bacteria and Xanthomonas campestris could prevent the hypersensitive response caused by an avirulent X. campestris strain. By use of a range of deep-rough mutants, the minimal structure in Salmonella LPS responsible for the elicitation of this effect was determined to be lipid A attached to a disaccharide of 2-keto-3-deoxyoctulosonate; lipid A alone and the free core oligosaccharide from a Salmonella Ra mutant were not effective. For Xanthomonas, the core oligosaccharide alone had activity although lipid A was not effective. The results suggest that pepper cells can recognize different structures within bacterial LPS to trigger alterations in plant response to avirulent pathogens.

Calculation studies of coated particles performance in sodium-cooled fast reactor

Kerntechnik ◽  
2021 ◽  
Vol 86 (1) ◽  
pp. 45-49
Author(s):  
N. V. Maslov ◽  
E. I. Grishanin ◽  
P. N. Alekseev
Keyword(s):  
Fast Reactor ◽  
Reactor Core ◽  
Heat Removal ◽  
Design Solution ◽  
Fast Neutrons ◽  
Steel Shell ◽  
Primary Circuit ◽  
Coated Particles ◽  
The Core ◽  
Fuel Assemblies

Abstract This paper presents results of calculation studies of the viability of coated particles in the conditions of the reactor core on fast neutrons with sodium cooling, justifying the development of the concept of the reactor BN with microspherical fuel. Traditional rod fuel assemblies with pellet MOX fuel in the core of a fast sodium reactor are directly replaced by fuel assemblies with micro-spherical mixed (U,Pu)C-fuel. Due to the fact that the micro-spherical (U, Pu)C fuel has a developed heat removal surface and that the design solution for the fuel assembly with coated particles is horizontal cooling of the microspherical fuel, the core has additional possibilities of increasing inherent (passive) safety and improve the competitiveness of BN type of reactors. It is obvious from obtained results that the microspherical (U, Pu)C fuel is limited with the maximal burn-up depth of ∼11% of heavy atoms in conditions of the sodium-cooled fast reactor core at the conservative approach; it gives the possibility of reaching stated thermal-hydraulic and neutron-physical characteristics. Such a tolerant fuel makes it less likely that fission products will enter the primary circuit in case of accidents with loss of coolant and the introduction of positive reactivity, since the coating of microspherical fuel withstands higher temperatures than the steel shell of traditional rod-type fuel elements.

A Semi-Formalization of the Dynamic Capability View

2018 ◽  
Author(s):  
Ralf Wilden ◽  
Timothy M. Devinney ◽  
Nidthida Lin
Keyword(s):  
Dynamic Capabilities ◽  
Dynamic Capability ◽  
Market Demand ◽  
Resource Base ◽  
Structured Model ◽  
The Core ◽  
Theoretical Status ◽  
Core Components ◽  
The Relationship ◽  
Core Construct

Some management scholars doubt the value of the dynamic capability view when compared to existing theories. The concern expressed is often related to unclear definitions of the core construct and the relationship among the components that make up that construct. The end result is potentially confused and conflicting interpretations of empirical findings and non-commensurate measurement. One solution is to formalize core components of the theory at hand. The purpose of this paper is not to discuss or argue for (or against) the theoretical status of the dynamic capability view, but to provide a simple, yet insightful, structured model of its core components. Specifically, this paper takes as its basis the perspective of dynamic capabilities as comprising the sensing, seizing, and reconfiguring processes that are deployed to create a resource base aimed at satisfying evolving market demand; it presents a simple but formal way of characterizing its components.

Performance of Core Exit Thermocouple for PWR Accident Management Action in Vessel Top Break LOCA Simulation Experiment at OECD/NEA ROSA Project

2008 ◽  
Author(s):  
Mitsuhiro Suzuki ◽  
Takeshi Takeda ◽  
Hideo Nakamura
Keyword(s):  
Time Delay ◽  
Large Scale ◽  
Simulation Experiment ◽  
Three Dimensional ◽  
Test Facility ◽  
Large Temperature ◽  
Energy Agency ◽  
Pressurized Water ◽  
The Core ◽  
Accident Management

Presented are experiment results of the Large Scale Test Facility (LSTF) conducted at the Japan Atomic Energy Agency (JAEA) with a focus on core exit thermocouple (CET) performance to detect core overheat during a vessel top break loss-of-coolant accident (LOCA) simulation experiment. The CET temperatures are used to start accident management (AM) action to quickly depressurize steam generator (SG) secondary sides in case of core temperature excursion. Test 6-1 is the first test of the OECD/NEA ROSA Project started in 2005, simulating withdraw of a control rod drive mechanism penetration nozzle at the vessel top head. The break size is equivalent to 1.9% cold leg break. The AM action was initiated when CET temperature rose up to 623K. There was no reflux water fallback onto the CETs during the core heat-up period. The core overheat, however, was detected with a time delay of about 230s. In addition, a large temperature discrepancy was observed between the CETs and the hottest core region. This paper clarifies the reasons of time delay and temperature discrepancy between the CETs and heated core during boil-off including three-dimensional steam flows in the core and core exit. The paper discusses applicability of the LSTF CET performance to pressurized water reactor (PWR) conditions and a possibility of alternative indicators for earlier AM action than in Test 6-1 is studied by using symptom-based plant parameters such as a reactor vessel water level detection.

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