22 Matching Results

Search Results

Advanced search parameters have been applied.
in creator/contributor: "Oh, Chang H."  
Results: 1 - 22
open access

Heat Exchanger Design Options and Tritium Transport Study for the VHTR System

Description: This report presents the results of a study conducted to consider heat exchanger options and tritium transport in a very high temperature reactor (VHTR) system for the Next Generation Nuclear Plant Project. The heat exchanger options include types, arrangements, channel patterns in printed circuit heat exchangers (PCHE), coolant flow direction, and pipe configuration in shell-and-tube designs. Study considerations include: three types of heat exchanger designs (PCHE, shell-and-tube, and helical… more
Date: September 1, 2008
Creator: Oh, Chang H. & Kim, Eung S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Design Configurations and Coupling High Temperature Gas-Cooled Reactor and Hydrogen Plant

Description: The US Department of Energy is investigating the use of high-temperature nuclear reactors to produce hydrogen using either thermochemical cycles or high-temperature electrolysis. Although the hydrogen production processes are in an early stage of development, coupling either of these processes to the high-temperature reactor requires both efficient heat transfer and adequate separation of the facilities to assure that off-normal events in the production facility do not impact the nuclear power … more
Date: April 1, 2008
Creator: Oh, Chang H.; Kim, Eung Soo & Sherman, Steven
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Computational Assessment of the GT-MHR Graphite Core Support Structural Integrity in Air-Ingress Accident Condition

Description: The objective of this project was to perform stress analysis for graphite support structures of the General Atomics’ 600 MWth GT-MHR prismatic core design using ABAQUS ® (ver. 6.75) to assess their structural integrity in air-ingress accident conditions where the structure weakens over time due to oxidation damages. The graphite support structures of prismatic type GT-MHR was analyzed based on the change of temperature, burn-off and corrosion depth during the accident period predicted by GAMMA,… more
Date: October 1, 2008
Creator: Lim, Jong B.; Kim, Eung S.; Oh, Chang H.; Schultz, Richard R. & Petti, David A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

STUDY ON AIR INGRESS MITIGATION METHODS IN THE VERY HIGH TEMPERATURE GAS COOLED REACTOR (VHTR)

Description: An air-ingress accident followed by a pipe break is considered as a critical event for a very high temperature gas-cooled reactor (VHTR). Following helium depressurization, it is anticipated that unless countermeasures are taken, air will enter the core through the break leading to oxidation of the in-core graphite structure. Thus, without mitigation features, this accident might lead to severe exothermic chemical reactions of graphite and oxygen. Under extreme circumstances, a loss of core str… more
Date: March 1, 2011
Creator: Oh, Chang H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Development of Tritium Permeation Analysis Code (TPAC)

Description: Idaho National Laboratory developed the Tritium Permeation Analysis Code (TPAC) for tritium permeation in the Very High Temperature Gas Cooled Reactor (VHTR). All the component models in the VHTR were developed and were embedded into the MATHLAB SIMULINK package with a Graphic User Interface. The governing equations of the nuclear ternary reaction and thermal neutron capture reactions from impurities in helium and graphite core, reflector, and control rods were implemented. The TPAC code was ve… more
Date: October 1, 2010
Creator: Kim, Eung S.; Oh, Chang H. & Patterson, Mike
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Method and System for the Production of Hydrogen at Reduced VHTR Outlet Temperatures

Description: The Department of Energy and the Idaho National Laboratory are developing a Next Generation Nuclear Plant (NGNP) to serve as a demonstration of state-of-the-art nuclear technology. The purpose of the demonstration is two fold 1) efficient low cost energy generation and 2) hydrogen production. Although a next generation plant could be developed as a single-purpose facility dedicated to hydrogen production, early designs are expected to be dual purpose. While hydrogen production and advanced ener… more
Date: October 1, 2009
Creator: Oh, Chang H. & Kim, Eung S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Effect of Reacting Surface Density on the Overall Graphite Oxidation Rate

Description: Graphite oxidation in an air-ingress accident is presently a very important issue for the reactor safety of the very high temperature gas cooled-reactor (VHTR), the concept of the next generation nuclear plant (NGNP) because of its potential problems such as mechanical degradation of the supporting graphite in the lower plenum of the VHTR might lead to core collapse if the countermeasure is taken carefully. The oxidation process of graphite has known to be affected by various factors, including… more
Date: May 1, 2009
Creator: Oh, Chang H.; Kim, Eung; Lim, Jong; Schultz, Richard & Petti, David
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Development and Verification of Tritium Analyses Code for a Very High Temperature Reactor

Description: A tritium permeation analyses code (TPAC) has been developed by Idaho National Laboratory for the purpose of analyzing tritium distributions in the VHTR systems including integrated hydrogen production systems. A MATLAB SIMULINK software package was used for development of the code. The TPAC is based on the mass balance equations of tritium-containing species and a various form of hydrogen (i.e., HT, H2, HTO, HTSO4, and TI) coupled with a variety of tritium source, sink, and permeation models. … more
Date: September 1, 2009
Creator: Oh, Chang H. & Kim, Eung S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Stress and Heat Transfer Analyses for Different Channel Arrangements of PCHE

Description: Stress and heat transfer analyses are being performed on the different channel arrangements of Printed Circuit Heat Exchanger (PCHE) proposed for application of VHTRs using ABAQUS [ABAQUS, 2007] and COMSOL [COMSOL, 2007], respectively. The work is being done to determine the configuration that would result in minimum stress for the same heat performance. This paper discusses the effects of shifting the coolant channels in every other row to reduce stress.
Date: November 1, 2008
Creator: Lim, Jong B.; Shrake, Robert G.; Kim, Eung S. & Oh, Chang H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

FINAL REPORT on Experimental Validation of Stratified Flow Phenomena, Graphite Oxidation, and Mitigation Strategies of Air Ingress Accidents

Description: The U.S. Department of Energy is performing research and development that focuses on key phenomena that are important during challenging scenarios that may occur in the Next Generation Nuclear Plant (NGNP)/Generation IV very high temperature reactor (VHTR). Phenomena Identification and Ranking studies to date have identified the air ingress event, following on the heels of a VHTR depressurization, as very important. Consequently, the development of advanced air ingress-related models and verifi… more
Date: January 1, 2011
Creator: Oh, Chang H.; Kim, Eung S.; NO, Hee C. & Cho, Nam Z.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Next Generation Nuclear Plant Methods Technical Program Plan

Description: One of the great challenges of designing and licensing the Very High Temperature Reactor (VHTR) is to confirm that the intended VHTR analysis tools can be used confidently to make decisions and to assure all that the reactor systems are safe and meet the performance objectives of the Generation IV Program. The research and development (R&D) projects defined in the Next Generation Nuclear Plant (NGNP) Design Methods Development and Validation Program will ensure that the tools used to perform th… more
Date: December 1, 2010
Creator: Schultz, Richard R.; Ougouag, Abderrafi M.; Nigg, David W.; Gougar, Hans D.; Johnson, Richard W.; Terry, William K. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Development of a Supercritical Carbon Dioxide Brayton Cycle: Improving VHTR Efficiency and Testing Material Compatibility - Final Report

Description: Generation IV reactors will need to be intrinsically safe, having a proliferation-resistant fuel cycle and several advantages relative to existing light water reactor (LWR). They, however, must still overcome certain technical issues and the cost barrier before it can be built in the U.S. The establishment of a nuclear power cost goal of 3.3 cents/kWh is desirable in order to compete with fossil combined-cycle, gas turbine power generation. This goal requires approximately a 30 percent reductio… more
Date: June 1, 2006
Creator: Oh, Chang H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Modular Pebble-Bed Reactor Project: Laboratory-Directed Research and Development Program FY 2002 Annual Report

Description: This report documents the results of our research in FY-02 on pebble-bed reactor technology under our Laboratory Directed Research and Development (LDRD) project entitled the Modular Pebble-Bed Reactor. The MPBR is an advanced reactor concept that can meet the energy and environmental needs of future generations under DOE’s Generation IV initiative. Our work is focused in three areas: neutronics, core design and fuel cycle; reactor safety and thermal hydraulics; and fuel performance.
Date: November 1, 2002
Creator: Petti, David Andrew; Dolan, Thomas James; Miller, Gregory Kent; Moore, Richard Leroy; Terry, William Knox; Ougouag, Abderrafi Mohammed-El-Ami et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

POWER CYCLE AND STRESS ANALYSES FOR HIGH TEMPERATURE GAS-COOLED REACTOR

Description: The Department of Energy and the Idaho National Laboratory are developing a Next Generation Nuclear Plant (NGNP) to serve as a demonstration of state-of-the-art nuclear technology. The purpose of the demonstration is two fold 1) efficient low cost energy generation and 2) hydrogen production. Although a next generation plant could be developed as a single-purpose facility, early designs are expected to be dual-purpose. While hydrogen production and advanced energy cycles are still in its early … more
Date: May 1, 2007
Creator: Oh, Chang H.; Davis, Cliff; Hawkes, Brian D. & Sherman, Steven R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Next Generation Nuclear Plant Methods Research and Development Technical Program Plan -- PLN-2498

Description: One of the great challenges of designing and licensing the Very High Temperature Reactor (VHTR) is to confirm that the intended VHTR analysis tools can be used confidently to make decisions and to assure all that the reactor systems are safe and meet the performance objectives of the Generation IV Program. The research and development (R&D) projects defined in the Next Generation Nuclear Plant (NGNP) Design Methods Development and Validation Program will ensure that the tools used to perform th… more
Date: September 1, 2008
Creator: Schultz, Richard R.; Ougouag, Abderrafi M.; Nigg, David W.; Gougar, Hans D.; Johnson, Richard W.; Terry, William K. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Isothermal Air Ingress Validation Experiments at Idaho National Laboratory: Description and Summary of Data

Description: Idaho National Laboratory performed air ingress experiments as part of validating computational fluid dynamics code (CFD). An isothermal stratified flow experiment was designed and set to understand stratified flow phenomena in the very high temperature gas cooled reactor (VHTR) and to provide experimental data for validating computer codes. The isothermal experiment focused on three flow characteristics unique in the VHTR air-ingress accident: stratified flow in the horizontal pipe, stratified… more
Date: September 1, 2010
Creator: Oh, Chang H. & Kim, Eung S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

AIR INGRESS ANALYSIS: COMPUTATIONAL FLUID DYNAMIC MODELS

Description: The Idaho National Laboratory (INL), under the auspices of the U.S. Department of Energy, is performing research and development that focuses on key phenomena important during potential scenarios that may occur in very high temperature reactors (VHTRs). Phenomena Identification and Ranking Studies to date have ranked an air ingress event, following on the heels of a VHTR depressurization, as important with regard to core safety. Consequently, the development of advanced air ingress-related mode… more
Date: August 1, 2010
Creator: Oh, Chang H.; Kim, Eung S.; Schultz, Richard; Gougar, Hans; Petti, David & Kang, Hyung S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Validations of CFD Code for Density-Gradient Driven Air Ingress Stratified Flow

Description: Air ingress into a very high temperature gas-cooled reactor (VHTR) is an important phenomena to consider because the air oxidizes the reactor core and lower plenum where the graphite structure supports the core region in the gas turbine modular helium reactor (GTMHR) design, thus jeopardizing the reactor’s safety. Validating the computational fluid dynamics (CFD) code used to analyze the air ingress phenomena is therefore an essential part of the safety analysis and the ultimate computation req… more
Date: May 1, 2010
Creator: Oh, Chang H.; Kim, Eung S.; Schultz, Richard & Petti, David
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Development of Tritium Permeation Analysis Code and Tritium Transport in a High Temperature Gas-Cooled Reactor Coupled with Hydrogen Production System

Description: Abstract – A tritium permeation analyses code (TPAC) was developed by Idaho National Laboratory for the purpose of analyzing tritium distributions in very high temperature reactor (VHTR) systems, including integrated hydrogen production systems. A MATLAB SIMULINK software package was used in developing the code. The TPAC is based on the mass balance equations of tritium-containing species and various forms of hydrogen coupled with a variety of tritium sources, sinks, and permeation models. In t… more
Date: June 1, 2010
Creator: Oh, Chang H.; Kim, Eung S. & Patterson, Mike
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Next Generation Nuclear Plant Methods Technical Program Plan -- PLN-2498

Description: One of the great challenges of designing and licensing the Very High Temperature Reactor (VHTR) is to confirm that the intended VHTR analysis tools can be used confidently to make decisions and to assure all that the reactor systems are safe and meet the performance objectives of the Generation IV Program. The research and development (R&D) projects defined in the Next Generation Nuclear Plant (NGNP) Design Methods Development and Validation Program will ensure that the tools used to perform th… more
Date: September 1, 2010
Creator: Schultz, Richard R.; Ougouag, Abderrafi M.; Nigg, David W.; Gougar, Hans D.; Johnson, Richard W.; Terry, William K. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

TRITIUM PERMEATION AND TRANSPORT IN THE GASOLINE PRODUCTION SYSTEM COUPLED WITH HIGH TEMPERATURE GAS-COOLED REACTORS (HTGRS)

Description: This paper describes scoping analyses on tritium behaviors in the HTGR-integrated gasoline production system, which is based on a methanol-to-gasoline (MTG) plant. In this system, the HTGR transfers heat and electricity to the MTG system. This system was analyzed using the TPAC code, which was recently developed by Idaho National Laboratory. The global sensitivity analyses were performed to understand and characterize tritium behaviors in the coupled HTGR/MTG system. This Monte Carlo based rand… more
Date: May 1, 2011
Creator: Oh, Chang H.; Kim, Eung S. & Patterson, Mike
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Scoping Analyses on Tritium Permeation to VHTR Integarted Industrial Application Systems

Description: Tritium permeation is a very important current issue in the very high temperature reactor (VHTR) because tritium is easily permeated through high temperature metallic surfaces. Tritium permeations in the VHTR-integrated systems were investigated in this study using the tritium permeation analysis code (TPAC) that was developed by Idaho National Laboratory (INL). The INL TPAC is a numerical tool that is based on the mass balance equations of tritium containing species and hydrogen (i.e. HT, H2, … more
Date: March 1, 2011
Creator: Oh, Chang H. & Kim, Eung S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
Back to Top of Screen