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Title: MELCOR Analysis of OSU Multi-Application Small Light Water Reactor (MASLWR) Experiment

Abstract

A multi-application small light water reactor (MASLWR) conceptual design was developed by Oregon State University (OSU) with emphasis on passive safety systems. The passive containment safety system employs condensation and natural circulation to achieve the necessary heat removal from the containment in case of postulated accidents. Containment condensation experiments at the MASLWR test facility at OSU are modeled and analyzed with MELCOR, a system-level reactor accident analysis computer code. The analysis assesses its ability to predict condensation heat transfer in the presence of noncondensable gas for accidents where high-energy steam is released into the containment. This work demonstrates MELCOR’s ability to predict the pressure-temperature response of the scaled containment. Our analysis indicates that the heat removal rates are underestimated in the experiment due to the limited locations of the thermocouples and applies corrections to these measurements by conducting integral energy analyses along with CFD simulation for confirmation. Furthermore, the corrected heat removal rate measurements and the MELCOR predictions on the heat removal rate from the containment show good agreement with the experimental data.

Authors:
 [1];  [1];  [2];  [3];  [1]
  1. Univ. of Wisconsin, Madison, WI (United States)
  2. Tsinghua Univ., Beijing (China)
  3. Oregon State Univ., Corvallis, OR (United States)
Publication Date:
Research Org.:
Univ. of Wisconsin, Madison, WI (United States); Oregon State Univ., Corvallis, OR (United States)
Sponsoring Org.:
USDOE Office of Nuclear Energy (NE)
OSTI Identifier:
1372322
Grant/Contract Number:
NE0000663
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nuclear Technology
Additional Journal Information:
Journal Volume: 198; Journal Issue: 3; Journal ID: ISSN 0029-5450
Publisher:
Taylor & Francis - formerly American Nuclear Society (ANS)
Country of Publication:
United States
Language:
English
Subject:
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; condensation; multi-application small light water reactor; MELCOR

Citation Formats

Yoon, Dhongik S., Jo, HangJin, Fu, Wen, Wu, Qiao, and Corradini, Michael L. MELCOR Analysis of OSU Multi-Application Small Light Water Reactor (MASLWR) Experiment. United States: N. p., 2017. Web. doi:10.1080/00295450.2017.1311119.
Yoon, Dhongik S., Jo, HangJin, Fu, Wen, Wu, Qiao, & Corradini, Michael L. MELCOR Analysis of OSU Multi-Application Small Light Water Reactor (MASLWR) Experiment. United States. doi:10.1080/00295450.2017.1311119.
Yoon, Dhongik S., Jo, HangJin, Fu, Wen, Wu, Qiao, and Corradini, Michael L. Tue . "MELCOR Analysis of OSU Multi-Application Small Light Water Reactor (MASLWR) Experiment". United States. doi:10.1080/00295450.2017.1311119. https://www.osti.gov/servlets/purl/1372322.
@article{osti_1372322,
title = {MELCOR Analysis of OSU Multi-Application Small Light Water Reactor (MASLWR) Experiment},
author = {Yoon, Dhongik S. and Jo, HangJin and Fu, Wen and Wu, Qiao and Corradini, Michael L},
abstractNote = {A multi-application small light water reactor (MASLWR) conceptual design was developed by Oregon State University (OSU) with emphasis on passive safety systems. The passive containment safety system employs condensation and natural circulation to achieve the necessary heat removal from the containment in case of postulated accidents. Containment condensation experiments at the MASLWR test facility at OSU are modeled and analyzed with MELCOR, a system-level reactor accident analysis computer code. The analysis assesses its ability to predict condensation heat transfer in the presence of noncondensable gas for accidents where high-energy steam is released into the containment. This work demonstrates MELCOR’s ability to predict the pressure-temperature response of the scaled containment. Our analysis indicates that the heat removal rates are underestimated in the experiment due to the limited locations of the thermocouples and applies corrections to these measurements by conducting integral energy analyses along with CFD simulation for confirmation. Furthermore, the corrected heat removal rate measurements and the MELCOR predictions on the heat removal rate from the containment show good agreement with the experimental data.},
doi = {10.1080/00295450.2017.1311119},
journal = {Nuclear Technology},
number = 3,
volume = 198,
place = {United States},
year = {Tue May 23 00:00:00 EDT 2017},
month = {Tue May 23 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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  • The Idaho National Engineering and Environmental Laboratory (INEEL), Nexant Inc. and the Oregon State University (OSU) have developed a Multi-Application Small Light Water Reactor (MASLWR) concept. The MASLWR is a small, safe and economic natural circulation pressurized light water reactor. MASLWR reactor module consists of an integral reactor/steam generator located in a steel cylindrical containment. The entire module is to be entirely shop fabricated and transported to site on most railways or roads. Two or more modules are located in a reactor building, each being submersed in a common, below grade cavity filled with water. For the most severe postulatedmore » accident, the volume of water in the cavity provides a passive ultimate heat sink for 3 or more days allowing the restoration of lost normal active heat removal systems. MASLWR thermal power of a single module is 150 MWt, primary system pressure 10.5 MPa, steam pressure1.52 MPa and the net electrical output is 35 - 50 MWe.« less
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