Record Details

Modification of Lower Plenum Structure for Mixing Promotion during Normal Operation of the High Temperature Gas Cooled Reactor

ScholarsArchive at Oregon State University

Field Value
Title Modification of Lower Plenum Structure for Mixing Promotion during Normal Operation of the High Temperature Gas Cooled Reactor
Names Gradecka, Malwina (creator)
Woods, Brian (advisor)
Date Issued 2015-06-17 (iso8601)
Note Graduation date: 2016
Abstract Since High Temperature Gas-cooled Reactors are being considered as most promising design of upcoming IV Gen reactors, thus key research areas were identified to address safety aspects of this design. Number of simulations and experiments need to be conducted in this field. In this study thermal-hydraulics aspects of coolant flow through Lower Plenum (LP) of HTGR were considered. In specific: flow characteristics, risk of temperature stratification in LP and hot streaking. As power profile is non-uniform across the core, jets of coolant exit the core region at different temperatures and enter the LP impinging on LP floor creating possibility of hot spots at LP structure and temperature stratification in the plenum itself. Large local temperature gradients can cause material degradation effects. To address those issues numerical simulation and an experiment were developed. The numerical simulation provides coolant flow velocity and temperature fields. The purpose of this study is developing a method for gas mixing promotion in the Lower Plenum of HTTF to reduce risk of the hot streaking and thermal stratification phenomena during normal operation. Following aspect are being examined: identification of gas flow behavior in lower plenum of HTTF based on CFD simulations, identification of hot streaking issue in the HTTF lower plenum using CFD tools, scooping study for available methods for mixing promotion and computational investigation of efficiency of selected method. Study includes description of experimental setup of HTTF, guidance for LP CFD modeling, results and analysis of CFD simulations and proposition of thermal mixing enhancement using available methods.
Genre Thesis/Dissertation
Access Condition http://creativecommons.org/licenses/by/3.0/us/
Topic HTR
Identifier http://hdl.handle.net/1957/56282

© Western Waters Digital Library - GWLA member projects - Designed by the J. Willard Marriott Library - Hosted by Oregon State University Libraries and Press