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Title: The role of SASSYS-1 in LMR (Liquid Metal Reactor) safety analysis

Abstract

The SASSYS-1 liquid metal reactor systems analysis computer code is currently being used as the principal tool for analysis of reactor plant transients in LMR development projects. These include the IFR and EBR-II Projects at Argonne National Laboratory, the FFTF project at Westinghouse-Hanford, the PRISM project at General Electric, the SAFR project at Rockwell International, and the LSPB project at EPRI. The SASSYS-1 code features a multiple-channel thermal-hydraulics core representation coupled with a point kinetics neutronics model with reactivity feedback, all combined with detailed one-dimensional thermal-hydraulic models of the primary and intermediate heat transport systems, including pipes, pumps, plena, valves, heat exchangers and steam generators. In addition, SASSYS-1 contains detailed models for active and passive shutdown and emergency heat rejection systems and a generalized plant control system model. With these models, SASSYS-1 provides the capability to analyze a wide range of transients, including normal operational transients, shutdown heat removal transients, and anticipated transients without scram events. 26 refs., 16 figs.

Authors:
;
Publication Date:
Research Org.:
Argonne National Lab., IL (USA)
OSTI Identifier:
7010985
Report Number(s):
CONF-880506-4
ON: DE88009939
DOE Contract Number:
W-31109-ENG-38
Resource Type:
Conference
Resource Relation:
Conference: Safety of next generation power reactors, Seattle, WA, USA, 1 May 1988
Country of Publication:
United States
Language:
English
Subject:
22 GENERAL STUDIES OF NUCLEAR REACTORS; LIQUID METAL COOLED REACTORS; REACTOR SAFETY; REACTOR SHUTDOWN; COMPUTER CODES; REACTOR CORES; S CODES; TRANSIENTS; REACTOR COMPONENTS; REACTORS; SAFETY; SHUTDOWNS; 220400* - Nuclear Reactor Technology- Control Systems

Citation Formats

Dunn, F.E., and Wei, T.Y.C. The role of SASSYS-1 in LMR (Liquid Metal Reactor) safety analysis. United States: N. p., 1988. Web.
Dunn, F.E., & Wei, T.Y.C. The role of SASSYS-1 in LMR (Liquid Metal Reactor) safety analysis. United States.
Dunn, F.E., and Wei, T.Y.C. Fri . "The role of SASSYS-1 in LMR (Liquid Metal Reactor) safety analysis". United States. doi:. https://www.osti.gov/servlets/purl/7010985.
@article{osti_7010985,
title = {The role of SASSYS-1 in LMR (Liquid Metal Reactor) safety analysis},
author = {Dunn, F.E. and Wei, T.Y.C.},
abstractNote = {The SASSYS-1 liquid metal reactor systems analysis computer code is currently being used as the principal tool for analysis of reactor plant transients in LMR development projects. These include the IFR and EBR-II Projects at Argonne National Laboratory, the FFTF project at Westinghouse-Hanford, the PRISM project at General Electric, the SAFR project at Rockwell International, and the LSPB project at EPRI. The SASSYS-1 code features a multiple-channel thermal-hydraulics core representation coupled with a point kinetics neutronics model with reactivity feedback, all combined with detailed one-dimensional thermal-hydraulic models of the primary and intermediate heat transport systems, including pipes, pumps, plena, valves, heat exchangers and steam generators. In addition, SASSYS-1 contains detailed models for active and passive shutdown and emergency heat rejection systems and a generalized plant control system model. With these models, SASSYS-1 provides the capability to analyze a wide range of transients, including normal operational transients, shutdown heat removal transients, and anticipated transients without scram events. 26 refs., 16 figs.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 1988},
month = {Fri Jan 01 00:00:00 EST 1988}
}

Conference:
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  • A balance-of-plant (BOP) model has been developed for use within the SASSYS-1 liquid-metal reactor systems analysis code. This model expands the scope of SASSYS-1 so that the code can explicitly model the waterside components of a nuclear power plant; previously, only the water side of the steam generators could be modeled, with the remainder of the water side represented by boundary conditions on the steam generator. The model represents the BOP a set of flow paths and path junctions; the mass and energy equations are solved at the junctions, and the momentum equation is solved along the flow paths. Themore » junctions are thus mass and energy cells, and the paths are momentum cells. The various waterside component models (pumps, valves, etc.) are specialized types of energy or momentum cells, as appropriate. The solution scheme implicitly couples the energy cells through the momentum cells and solves simultaneously for pressures and enthalpies within the energy cells and for flows within the momentum cells.« less
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  • This paper presents a review of research on key US reactor safety issues in liquid-metal-cooled reactors (LMRs) over the past decade. The discussion is structured into two time domains: 1) the FFTF/CRBRP era, which featured a mixed oxide fuel system, and 2) the present era which emphasizes passive safety and a renewed emphasis on metal fuel. Issues in the FFTF and CRBRP era include local fault tolerance, core energetics potential (in response to unprotected transient overpower, loss of flow, or loss of heat sink events), and containment considerations. Issues of current interest focus much more heavily on reactivity feedbacks capablemore » of preventing the core from entering into a state of disruption /endash/ even for very low probability postulated events. Overall, the RandD over the past decade has provided generally favorable answers to safety concerns expressed in the early days of LMR design. Furthermore, the more recent programmatic directions /endash/ which emphasize passive safety /endash/ provide even stronger assurances that LMRs can be built which are exceptionally robust. 75 refs., 4 figs., 2 tabs.« less