Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Nuclear Engineering and Technology
Journal Basic Information
Journal DOI :
Korean Nuclear Society
Editor in Chief :
Volume & Issues
Volume 38, Issue 8 - Dec 2006
Volume 38, Issue 7 - Oct 2006
Volume 38, Issue 6 - Aug 2006
Volume 38, Issue 5 - Jul 2006
Volume 38, Issue 4 - Jun 2006
Volume 38, Issue 3 - Apr 2006
Volume 38, Issue 2 - Feb 2006
Volume 38, Issue 1 - Feb 2006
Selecting the target year
U.S. GENERATION IV REACTOR INTEGRATED MATERIALS TECHNOLOGY PROGRAM
Corwin William R. ;
Nuclear Engineering and Technology, volume 38, issue 7, 2006, Pages 591~618
An integrated R&D program is being conducted to study, qualify, and in some cases, develop materials with required properties for the reactor systems being developed as part the U.S. Department of Energy's Generation IV Reactor Program. The goal of the program is to ensure that the materials research and development (R&D) needed to support Gen IV applications will comprise a comprehensive and integrated effort to identify and provide the materials data and its interpretation needed for the design and construction of the selected advanced reactor concepts. The major materials issues for the five primary systems that have been considered within the U.S. Gen IV Reactor Program-very high temperature gas-cooled, supercritical water-cooled, gas-cooled fast spectrum, lead-cooled fast spectrum, and sodium-cooled fast spectrum reactors-are described along with the R&D that has been identified to address them.
STRAIN LOCALIZATION IN IRRADIATED MATERIALS
Byun, Thaksang ; Hashimoto, Naoyuki ;
Nuclear Engineering and Technology, volume 38, issue 7, 2006, Pages 619~638
Low temperature irradiation can significantly harden metallic materials and often lead to strain localization and ductility loss in deformation. This paper provides a review on the radiation effects on the deformation of metallic materials, focusing on microscopic and macroscopic strain localization phenomena. The types of microscopic strain localization often observed in irradiated materials are dislocation channeling and deformation twinning, in which dislocation glides are evenly distributed and well confined in the narrow bands, usually a fraction of a micron wide. Dislocation channeling is a common strain localization mechanism observed virtually in all irradiated metallic materials with ductility, while deformation twinning is an alternative localization mechanism occurring only in low stacking fault energy(SFE) materials. In some high stacking fault energy materials where cross slip is easy, curved and widening channels can be formed depending on dose and stress state. Irradiation also prompts macroscopic strain localization (or plastic instability). It is shown that the plastic instability stress and true fracture stress are nearly independent of irradiation dose if there is no radiation-induced phase change or embrittlement. A newly proposed plastic Instability criterion is that the metals after irradiation show necking at yield when the yield stress exceeds the dose-independent plastic instability stress. There is no evident relationship between the microscopic and macroscopic strain localizations; which is explained by the long-range back-stress hardening. It is proposed that the microscopic strain localization is a generalized phenomenon occurring at high stress.
REVIEW OF DYNAMIC LOADING J-R TEST METHOD FOR LEAK BEFORE BREAK OF NUCLEAR PIPING
Oh, Young-Jin ; Hwang, Il-Soon ;
Nuclear Engineering and Technology, volume 38, issue 7, 2006, Pages 639~656
In order to apply the leak before break (LBB) concept to nuclear piping systems, the dynamic strain aging effect of low carbon steel materials has to be taken into account, in compliance with the requirements of the Korean Standard Review Guide (KSRG) 3.6.3-1. For this goal, J-R tests are needed for a range of various temperatures and loading rates, including dynamic loading conditions. In the dynamic loading J-R test, the unloading compliance method can not be applied to measure the crack growth and direct current potential drop (DCPD) method; this method also has a problem defining the crack initiation point. The normalization method is known as a very useful method to determine the J-R curve under dynamic loading because it does not need additional equipment or complicated loading sequences such as electric current or unloading. This method was accepted by the American Society for Testing and Materials (ASTM) as a standard test method E1820 A15 in 2001. However, it has not yet been clearly verified yet if the normalization method is sufficiently reliable to be applied to LBB. In this study, the basic background of the J-integral, LBB and dynamic loading J-R test are explained, and the current status for dynamic loading J-R test methods are reviewed from the view point of LBB for nuclear piping. In particular, the theoretical and historical background of the normalization method which has received attention recently, is summarized. Recent studies for this method are introduced and future works are suggested that may improve the reliability of LBB for nuclear piping.
REACTIVITY OSCILLATION IN SOURCE-DRIVEN SYSTEMS
Dulla, S. ; Nicolino, C. ; Ravetto, P. ;
Nuclear Engineering and Technology, volume 38, issue 7, 2006, Pages 657~664
The problem of reactivity oscillations for a point reactor constitutes an interesting aspect of nuclear reactor physics and its solution may give important information for dynamic and safety assessments. The present paper considers the problem of a reactivity oscillation for a source-driven system which involves some specific aspects that introduce significant differences with respect to the source-free situation. Assuming a square-wave shape for the reactivity insertion, the solution is derived by a fully analytical approach. The conditions for stability and instability can be identified in a straightforward way by directly studying the stationarity of the power response. Numerical results presented allow to discuss the role of the system kinetic parameters and of the time-shape of the reactivity wave.
EVALUATION OF FAST NEUTRON FLUENCE FOR KORI UNIT 3 PRESSURE VESSEL
Yoo, Choon-Sung ; Kim, Byoung-Chul ; Chang, Kee-Ok ; Lee, Sam-Lai ; Park, Jong-Ho ;
Nuclear Engineering and Technology, volume 38, issue 7, 2006, Pages 665~674
Three-dimensional neutron flux and fluence of Kori Unit 3 were evaluated using the synthesis technique described in Regulatory Guide 1.190 for all reactor geometry. For this purpose DORT neutron transport calculations from Cycle 1 to Cycle 15 were performed using BUGLE-96 cross-section library. The calculated flux and fluence were validated by comparing the calculated reaction rates to the measurement data from the dosimetry sensor set of the
surveillance capsule withdrawn at the end of cycle 15 of Kori Unit 3. And then the best estimation of the neutron exposures for the reactor vessel beltline region was performed using the least square evaluation. These results can be used in the assessment of the state of embrittlement of Kori Unit 3 pressure vessel.
DESIGN OF A NEUTRON SCREEN FOR 6-INCH NEUTRON TRANSMUTATION DOPING IN HANARO
Kim, Hak-Sung ; Oh, Soo-Youl ; Jun, Byung-Jin ; Kim, Myong-Seop ; Seo, Chul-Gyo ; Kim, Heon-Il ;
Nuclear Engineering and Technology, volume 38, issue 7, 2006, Pages 675~680
The neutron transmutation doping of silicon (NTD), as a method to produce a high quality semiconductor, utilizes the transmutation of a silicon element into phosphorus by neutron absorption in a silicon single crystal. In this paper, we present the design of a neutron screen for a 6' Si ingot irradiation in the NTD2 hole of HANARO. The goal of the design is to achieve an even flat axial distribution of the resistivity, or
reaction rate, in the irradiated Si ingot. We used the MCNP4C code to simulate the neutron screen and to calculate the reaction rate distribution in the Si ingot. The fluctuations in the axial distribution were estimated to be within
from the average for the final neutron screen design; thus, they satisfy the customers' requirement for uniform irradiation. On the other hand, we determined the optimal insertion depths of the Si ingots by varying the critical control rod position, which greatly affects the axial flux distribution.
IMPACT ANALYSIS OF A WATER STORAGE TANK
Jhung, Myung-Jo ; Jo, Jong-Chull ; Jeong, Sang-Jin ;
Nuclear Engineering and Technology, volume 38, issue 7, 2006, Pages 681~688
This study investigates the dynamic response characteristics of a structure impacted by a high speed projectile. The impact of a 300 kg projectile on a water storage tank is simulated by the general purpose computer codes ANSYS and LS-DYNA. Several methods to simulate the impact are considered and their results are compared. Based upon this, an alternative impact analysis method that is equivalent to an explicit dynamic analysis is proposed. The effect of fluid on the responses of the tank is also addressed.
EQUIVALENT MATERIAL PROPERTIES OF PERFORATED PLATE WITH TRIANGULAR OR SQUARE PENETRATION PATTERN FOR DYNAMIC ANALYSIS
Jhung, Myung-Jo ; Jo, Jong-Chull ;
Nuclear Engineering and Technology, volume 38, issue 7, 2006, Pages 689~696
For a perforated plate, it is challenging to develop a finite element model due to the necessity of the fine meshing of the plate, especially if it is submerged in fluid. This necessitates the use of a solid plate with equivalent material properties. Unfortunately, the effective elastic constants suggested by the ASME code are deemed not valid for a modal analysis. Therefore, in this study the equivalent material properties of a perforated plate are suggested by performing several finite element analyses with respect to the ligament efficiencies.