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Title: Initial Implementation of Transient VERA-CS

Abstract

In this milestone the capabilities of both CTF and MPACT were extended to perform coupled transient calculations. This required several small changes in MPACT to setup the problems correctly, perform the edits correctly, and call the appropriate CTF interfaces in the right order. For CTF, revisions and corrections to the transient timestepping algorithm were made, as well as the addition of a new interface subroutine to allow MPACT to drive CTF at each timestep. With the modifications completed, the initial coupled capability was demonstrated on some problems used for code verification, a hypothetical small mini-core, and a Watts Bar demonstration problem. For each of these cases the results showed good agreement with the previous MPACT internal TH feedback model that relied on a simplified fuel heat conduction model and simplified coolant treatment. After the pulse the results are notably different as expected, where the effects of convection of heat to the coolant can be observed. Areas for future work were discussed, including assessment and development of the CTF dynamic fuel deformation and gap conductance models, addition of suitable transient boiling and CHF models for the rapid heating and cooling rates seen in RIAs, additional validation and demonstration work, and areasmore » for improvement to the code input and output capabilities.« less

Authors:
 [1];  [1];  [2]; ORCiD logo [2]
  1. Univ. of Michigan, Ann Arbor, MI (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1409277
Report Number(s):
ORNL/TM-2017/192
74178
DOE Contract Number:
AC05-00OR22725
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
97 MATHEMATICS AND COMPUTING

Citation Formats

Gerlach, Andrew, Kochunas, Brendan, Salko, Robert, and Wysocki, Aaron J. Initial Implementation of Transient VERA-CS. United States: N. p., 2017. Web. doi:10.2172/1409277.
Gerlach, Andrew, Kochunas, Brendan, Salko, Robert, & Wysocki, Aaron J. Initial Implementation of Transient VERA-CS. United States. doi:10.2172/1409277.
Gerlach, Andrew, Kochunas, Brendan, Salko, Robert, and Wysocki, Aaron J. 2017. "Initial Implementation of Transient VERA-CS". United States. doi:10.2172/1409277. https://www.osti.gov/servlets/purl/1409277.
@article{osti_1409277,
title = {Initial Implementation of Transient VERA-CS},
author = {Gerlach, Andrew and Kochunas, Brendan and Salko, Robert and Wysocki, Aaron J.},
abstractNote = {In this milestone the capabilities of both CTF and MPACT were extended to perform coupled transient calculations. This required several small changes in MPACT to setup the problems correctly, perform the edits correctly, and call the appropriate CTF interfaces in the right order. For CTF, revisions and corrections to the transient timestepping algorithm were made, as well as the addition of a new interface subroutine to allow MPACT to drive CTF at each timestep. With the modifications completed, the initial coupled capability was demonstrated on some problems used for code verification, a hypothetical small mini-core, and a Watts Bar demonstration problem. For each of these cases the results showed good agreement with the previous MPACT internal TH feedback model that relied on a simplified fuel heat conduction model and simplified coolant treatment. After the pulse the results are notably different as expected, where the effects of convection of heat to the coolant can be observed. Areas for future work were discussed, including assessment and development of the CTF dynamic fuel deformation and gap conductance models, addition of suitable transient boiling and CHF models for the rapid heating and cooling rates seen in RIAs, additional validation and demonstration work, and areas for improvement to the code input and output capabilities.},
doi = {10.2172/1409277},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month =
}

Technical Report:

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