Download or read book BWR Transient Response written by S. P. Kalra and published by . This book was released on 1982 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book BWR Anticipated Transients Without Scram Leading to Instability written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Anticipated transients without scram (ATWS) in aboiling water reactor (BWR) were simulated in order to understand reactor response and determine the effectiveness of automatic and operator actions to mitigate this beyond-design-basis accident. The events of interest herein are initiated by a turbine trip when the reactor is operating in the expanded operating domainMELLLA+ [maximum extended load line limit plus]. In these events the reactor may initially be at up to 120% of the original licensed thermal power (OLTP) and at flow rates as low as 80% of rated. For these (and similar) ATWS events the concern isthat when the reactor power decreases in response to a dual recirculation pump trip, the core will become unstable and large amplitude oscillations will begin. The occurrence of these power oscillations, if left unmitigated, may result in fuel damage, and the amplitude of the poweroscillations may hamper the effectiveness of the injection of dissolved neutron absorber through the standby liquid control system (SLCS).
Download or read book BWR ANTICIPATED TRANSIENTS WITHOUT SCRAM IN THE MELLLA EXPANDED OPERATING DOMAIN Part 2 written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the second in a series of reports on the response of a BWR/5 boiling water reactor to anticipated transients without reactor scram (ATWS) when operating in the expanded operating domain MELLLA+. In this report ATWS events initiated by a turbine trip are considered at two points in the fuel cycle: beginning of cycle (BOC) and peak excess reactivity (PHE, close to the middle of the cycle). The effect of the gap (between the fuel pellet and clad) conductance modeling, turbine bypass fractions, and initial core flow rates are evaluated. Two limiting values of gas-gap conductance, the lowest value of 5,000 W/m2-K at BOC and the highest value of 161,000 W/m2-K at PHE, are compared with corresponding base cases which utilized the dynamic gas-gap model. Turbine bypass fractions analyzed are 10% and 25% at PHE and these two sensitivity cases are compared with the 100% bypass base case. The reduced core flow case at 75% of nominal core flow is analyzed at PHE and compared with the base case of 85% core flow. The simulations were carried out using the TRACE/PARCS code system and models developed for a previous study at three different times during a fuel cycle with all relevant BWR/5 systems. The modeling in the core is particularly detailed (four fuel rod types included in each fuel assembly and 382 thermal-hydraulic channels to represent all assemblies taking into account half-core symmetry) in order to capture the complex neutronic-thermal-hydraulic coupling during periods of instability. The study provides insights into reactor behavior during these events, including the impact of assumed operator actions on the oscillatory behavior due to reactor instabilities and on the eventual shutdown of the reactor. It shows the effect of gap conductance, turbine bypass fraction and initial flow rate. and #8195.
Download or read book Weekly Information Report written by and published by . This book was released on 1988 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book BWR ANTICIPATED TRANSIENTS WITHOUT SCRAM IN THE MELLLA EXPANDED OPERATING DOMAIN Part 4 written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the fourth in a series of reports on the response of a BWR/5 boiling water reactor to anticipated transients without reactor scram (ATWS) when operating in the expanded operating domain MELLLA+. In this report ATWS events initiated by closure of main steam isolation valves are analyzed at beginning-of-cycle, and end-of-full-power-life, conditions. The objective is to understand the sensitivity of ATWS-ED events to the intial operating core flow and to the spectrally corrected moderator density history (void history). Different water level control strategies are considered. The ATWS events are simulated for a sufficiently long time (2500 s) to understand the response of key components and the potential for fuel damage or damage to the wetwell (suppression pool). These events lead to the automatic trip of recirculation pumps; and operator actions to activate the emergency depressurization system when the wetwell has reached the heat capacity temperature limit, and to control power through water level control and the injection of soluble boron. The simulations were carried out using the TRACE/PARCS code system and models developed for a previous study with all relevant BWR/5 systems.
Download or read book Nuclear Safety written by and published by . This book was released on 1973 with total page 1594 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book BWR 4 Loss of Feedwater Transient Analysis written by and published by . This book was released on 1983 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper presents an analysis of a series of loss of feedwater (LOF) transients for a typical BWR/4 reactor. These calculations were prompted by the events that occurred during the TMI incident and hence include various assumed failures in the safety/relief valve system and the assumed inoperability of various safety systems. This analysis provides transient results necessary to evaluate the potential for core uncovery and excessive average fuel temperatures which can then be used in the evaluation of the adequacy of the engineered safety features and the plant operating procedures. The RELAP5/MOD1 computer code was used for this analysis. The version of the code is designated as Cycle 13 with additional modifications provided by INEL. The modifications affect the jet pump model, interphase drag model and separator model.
Download or read book ANS Topical Meeting written by American Nuclear Society. Topical Meeting and published by . This book was released on 1964 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book TID written by and published by . This book was released on 1964 with total page 478 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nuclear Regulatory Commission Issuances written by U.S. Nuclear Regulatory Commission and published by . This book was released on 2007 with total page 896 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Sensitivity Study of the Critical Flow Models Used in RELAP4 MOD 5 Blowdown Analysis of a General Electric BWR written by Mark Vearil Carle and published by . This book was released on 1978 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study uses the RELAP4/MOD5 Computer Code to analyze the effects of critical flow modeling on the thermal-hydraulic transient response of a General Electric boiling water reactor to a major primary coolant line rupture. Included is a presentation of the equations, assumptions, and limitations of the critical flow models available for use in RFLAP4. Additionally, an evaluation of a temporary solution to a RELAP4 coding error associated with stagnation properties calculation is presented.
Download or read book TRACE SIMULATION OF BWR ANTICIPATED TRANSIENT WITHOUT SCRAM LEADING TO EMERGENCY DEPRESSURIZATION written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book EPRI NP written by and published by . This book was released on 19?? with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book TRAB written by Markku Rajamäki and published by . This book was released on 1991 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Contributions from Moderate Frequency Transient Initiators in a BWR PRA written by and published by . This book was released on 1985 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Transients are significant contributors to the core damage frequency in Boiling Water Reactors (BWR). The main contribution comes from transients with frequency of occurrence in the range of 3 to 100 events during plant lifetime (30 to 40 years). Examples of these transients are turbine trip, loss of condenser, and inadvertently open relief valve (IORV). Reviews by BNL of BRW PRAs appear to indicate that moderate frequency transients also could significantly contribute to the total core damage frequency. Moderate frequency transients are those events having frequencies ranging from 0.1 to 3 times per plant lifetime. The present study discusses some of these events and identifies conditions that make their contribution to plant core damage frequency significant.
Download or read book Corrosion Issues in Light Water Reactors written by D Féron and published by Elsevier. This book was released on 2007-06-22 with total page 369 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stress corrosion cracking is a major problem in light water nuclear reactors, whether pressurised water reactors (PWRs) or boiling water reactors (BWRs). The nuclear industry needs to be able to predict the service life of these power plants and develop appropriate maintenance and repair practices to ensure safe long term operation. This important book sums up key recent research on corrosion in light water reactors and its practical applications. The book is divided into four parts. It begins with an overview of materials degradation due to stress corrosion, corrosion potential monitoring and passivation. Part two summarises research on susceptibility of materials to stress corrosion cracking and the ways it can be initiated. The third part of the book considers stress corrosion crack propagation processes whilst the final part includes practical case studies of corrosion in particular plants. The book reviews corrosion in a range of materials such as low alloy steels, stainless steels and nickel-based alloys. With its distinguished editor and team of contributors, Corrosion issues in light water reactors is a standard work for the nuclear industry. Summarises key recent research on corrosion in light water reactors Includes practical case studies
Download or read book Energy Research Abstracts written by and published by . This book was released on 1989 with total page 1468 pages. Available in PDF, EPUB and Kindle. Book excerpt:
