Validation of hydrogen gas stratification and mixing models

Wu, Hsingtzu; Zhao, Haihua

doi:10.1016/j.anucene.2015.05.003

Title: Validation of hydrogen gas stratification and mixing models

Full Record
Other Related Research

Abstract

Two validation benchmarks confirm that the BMIX++ code is capable of simulating unintended hydrogen release scenarios efficiently. The BMIX++ (UC Berkeley mechanistic MIXing code in C++) code has been developed to accurately and efficiently predict the fluid mixture distribution and heat transfer in large stratified enclosures for accident analyses and design optimizations. The BMIX++ code uses a scaling based one-dimensional method to achieve large reduction in computational effort compared to a 3-D computational fluid dynamics (CFD) simulation. Two BMIX++ benchmark models have been developed. One is for a single buoyant jet in an open space and another is for a large sealed enclosure with both a jet source and a vent near the floor. Both of them have been validated by comparisons with experimental data. Excellent agreements are observed. The entrainment coefficients of 0.09 and 0.08 are found to fit the experimental data for hydrogen leaks with the Froude number of 99 and 268 best, respectively. In addition, the BIX++ simulation results of the average helium concentration for an enclosure with a vent and a single jet agree with the experimental data within a margin of about 10% for jet flow rates ranging from 1.21 × 10⁻⁴ to 3.29 ×more »« less

Authors:

Wu, Hsingtzu ^[1]; Zhao, Haihua ^[2]

Japan Atomic Energy Agency (JAEA), Tokai (Japan)
Idaho National Lab. (INL), Idaho Falls, ID (United States)

Publication Date:: Tue May 26 00:00:00 EDT 2015

Research Org.:: Idaho National Laboratory (INL), Idaho Falls, ID (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1184714

Alternate Identifier(s):: OSTI ID: 1247872

Report Number(s):: INL/JOU-14-32658
Journal ID: ISSN 0306-4549; TRN: US1500199

Grant/Contract Number:: AC07-05ID14517

Resource Type:: Accepted Manuscript

Journal Name:: Annals of Nuclear Energy (Oxford)

Additional Journal Information:: Journal Name: Annals of Nuclear Energy (Oxford); Journal Volume: 85; Journal Issue: C; Journal ID: ISSN 0306-4549

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 22 GENERAL STUDIES OF NUCLEAR REACTORS; 97 MATHEMATICS AND COMPUTING; HELIUM; COMPUTERIZED SIMULATION; HYDROGEN; VALIDATION; COMPARATIVE EVALUATIONS; JETS; URANIUM CARBIDES; MIXING; B CODES; FLUID MECHANICS; HEAT TRANSFER; BENCHMARKS; MIXTURES; VENTS; FLOW RATE; ONE-DIMENSIONAL CALCULATIONS; ABUNDANCE; REACTOR ACCIDENTS; DESIGN; OPTIMIZATION; DISTRIBUTION; ENTRAINMENT; LEAKS; buoyant jets; enclosure mixing; hydrogen stratification; hydrogen leaks

Citation Formats


                    Wu, Hsingtzu, and Zhao, Haihua. Validation of hydrogen gas stratification and mixing models.  United States: N. p., 2015. 
Web.  doi:10.1016/j.anucene.2015.05.003.

Copy to clipboard


                    Wu, Hsingtzu, & Zhao, Haihua. Validation of hydrogen gas stratification and mixing models.  United States.  https://doi.org/10.1016/j.anucene.2015.05.003

Copy to clipboard


                    Wu, Hsingtzu, and Zhao, Haihua. Tue .  
"Validation of hydrogen gas stratification and mixing models".  United States.  https://doi.org/10.1016/j.anucene.2015.05.003.  https://www.osti.gov/servlets/purl/1184714.

Copy to clipboard


                    
@article{osti_1184714,

  title        = {Validation of hydrogen gas stratification and mixing models},

  author       = {Wu, Hsingtzu and Zhao, Haihua},

  abstractNote = {Two validation benchmarks confirm that the BMIX++ code is capable of simulating unintended hydrogen release scenarios efficiently. The BMIX++ (UC Berkeley mechanistic MIXing code in C++) code has been developed to accurately and efficiently predict the fluid mixture distribution and heat transfer in large stratified enclosures for accident analyses and design optimizations. The BMIX++ code uses a scaling based one-dimensional method to achieve large reduction in computational effort compared to a 3-D computational fluid dynamics (CFD) simulation. Two BMIX++ benchmark models have been developed. One is for a single buoyant jet in an open space and another is for a large sealed enclosure with both a jet source and a vent near the floor. Both of them have been validated by comparisons with experimental data. Excellent agreements are observed. The entrainment coefficients of 0.09 and 0.08 are found to fit the experimental data for hydrogen leaks with the Froude number of 99 and 268 best, respectively. In addition, the BIX++ simulation results of the average helium concentration for an enclosure with a vent and a single jet agree with the experimental data within a margin of about 10% for jet flow rates ranging from 1.21 × 10⁻⁴ to 3.29 × 10⁻⁴ m³/s. In conclusion, computing time for each BMIX++ model with a normal desktop computer is less than 5 min.},

  doi          = {10.1016/j.anucene.2015.05.003},

  journal      = {Annals of Nuclear Energy (Oxford)},

  number       = C,

  volume       = 85,

  place        = {United States},

  year         = {Tue May 26 00:00:00 EDT 2015},

  month        = {Tue May 26 00:00:00 EDT 2015}

}

Copy to clipboard

Journal Article:

Free Publicly Available Full Text

Accepted Manuscript (Publisher)

Accepted Manuscript (DOE)

Publisher's Version of Record

https://doi.org/10.1016/j.anucene.2015.05.003

Other availability

Search WorldCat to find libraries that may hold this journal

Citation Metrics:

Cited by: 3 works

Citation information provided by
Web of Science

Save / Share:

Export Metadata

Save to My Library

Similar Records in DOE PAGES and OSTI.GOV collections:

An efficient modeling method for thermal stratification simulation in a BWR suppression pool

Conference Zhao, Haihua ; Zou, Ling ; Zhang, Hongbin ; ...

The suppression pool in a BWR plant not only is the major heat sink within the containment system, but also provides major emergency cooling water for the reactor core. In several accident scenarios, such as LOCA and extended station blackout, thermal stratification tends to form in the pool after the initial rapid venting stage. Accurately predicting the pool stratification phenomenon is important because it affects the peak containment pressure; and the pool temperature distribution also affects the NPSHa (Available Net Positive Suction Head) and therefore the performance of the pump which draws cooling water back to the core. Current safetymore »« less
Full Text Available
Simulation of Thermal Stratification in BWR Suppression Pools with One Dimensional Modeling Method

Journal Article Zhao, Haihua ; Zou, Ling ; Zhang, Hongbin - Annals of Nuclear Energy (Oxford)

The suppression pool in a boiling water reactor (BWR) plant not only is the major heat sink within the containment system, but also provides the major emergency cooling water for the reactor core. In several accident scenarios, such as a loss-of-coolant accident and extended station blackout, thermal stratification tends to form in the pool after the initial rapid venting stage. Accurately predicting the pool stratification phenomenon is important because it affects the peak containment pressure; the pool temperature distribution also affects the NPSHa (available net positive suction head) and therefore the performance of the Emergency Core Cooling System and Reactormore »« less
https://doi.org/10.1016/j.anucene.2013.08.031
One-Dimensional Analysis of Thermal Stratification in AHTR and SFR Coolant Pools

Conference Zhao, Haihua ; Peterson, Per F

Thermal stratification phenomena are very common in pool type reactor systems, such as the liquid-salt cooled Advanced High Temperature Reactor (AHTR) and liquid-metal cooled fast reactor systems such as the Sodium Fast Reactor (SFR). It is important to accurately predict the temperature and density distributions both for design optimation and accident analysis. Current major reactor system analysis codes such as RELAP5 (for LWR’s, and recently extended to analyze high temperature reactors), TRAC (for LWR’s), and SASSYS (for liquid metal fast reactors) only provide lumped-volume based models which can only give very approximate results and can only handle simple cases withmore »« less
Full Text Available
Mixing processes in high-level waste tanks. Progress report, September 15, 1996--September 14, 1997

Technical Report Peterson, P F

'U.C. Berkeley has made excellent progress in the last year in building and running experiments and performing analysis to study mixing processes that can affect the distribution of fuel and oxygen in the air space of DOE high-level waste tanks, and the potential to create flammable concentrations at isolated locations, achieving all of the milestones outlined in the proposal. The DOE support has allowed the acquisition of key experimental equipment, and has funded the full-time efforts of one doctoral student and one postdoctoral researcher working on the project. In addition, one masters student and one other doctoral student, funded bymore »« less
https://doi.org/10.2172/13485

Full Text Available
High-resolution time-resolved experiments on mixing and entrainment of buoyant jets in stratified environments

Technical Report Manera, Annalisa ; Bardet, Philippe ; Petrov, Victor

Fluid jets interacting with a stratified layer play an important role in the safety of several reactor designs. In the containment of nuclear power plants, fluid jets dominate the transport and mixing of gaseous species and consequent hydrogen distribution in case of a severe accident. The mixing phenomena in the containment are driven by buoyant high-momentum injections (jets) and low momentum injection plumes. Mixing near the postulated break is initially dominated by high flow velocities. Plumes with moderate flow velocities are instead relevant in the break compartment during the long-term pressurization phase, or in any of the apertures between twomore »« less
https://doi.org/10.2172/1437156

Full Text Available

Similar Records