Analysis on inadvertent operation of decay heat removal system in NuScale reactor

A Sodium-cooled Fast Reactor (SFR) has receiving attention as one of the promising next generation nuclear reactors because it can recycle the spent nuclear fuel produced from the current commercial nuclear reactors and accomplish higher thermal efficiency than the current commercial nuclear reactors. However, after shutdown of the nuclear reactor core, the accumulated fission products of the SFR also decay and release heat via radiation within the reactor. To remove this residual heat, a decay heat removal system (DHRS) with supercritical CO2 (S-CO2) as the working fluid is suggested with a turbocharger system which achieves passive operational capability. However, for designing this system an improved S-CO2 turbine design methodology should be suggested because the existing methodology for designing the S-CO2 Brayton cycle has focused only on the compressor design near the critical point. To develop a S-CO2 turbine design methodology, the non-dimensional number based design and the 1D mean line design method were modified and suggested. The design methodology was implemented into the developed code and the code results were compared with existing turbine experimental data. The data were collected under air and S-CO2 environment. The developed code in this research showed a reasonable agreement with the experimental data. Finally using the design code, the turbocharger design for the suggested DHRS and prediction of the off design performance were carried out. As further works, more effort will be put it to expand the S-CO2 turbine test data for validating the design code and methodology.

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Thermal-hydraulic analysis of an innovative decay heat removal system for lead-cooled fast reactors

Nuclear Engineering and Design ◽

10.1016/j.nucengdes.2016.05.005 ◽

2016 ◽

Vol 305 ◽

pp. 168-178 ◽

Cited By ~ 9

Author(s):

Fabio Giannetti ◽

Damiano Vitale Di Maio ◽

Antonio Naviglio ◽

Gianfranco Caruso

Keyword(s):

Heat Removal ◽

Hydraulic Analysis ◽

Fast Reactors ◽

Decay Heat ◽

Heat Removal System ◽

Thermal Hydraulic Analysis ◽

Removal System

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Feasibility Investigation of the Decay Heat Removal Capability Using the Concept of a Thermosyphon in the Liquid Metal Reactor

10th International Conference on Nuclear Engineering, Volume 2 ◽

10.1115/icone10-22564 ◽

2002 ◽

Author(s):

Yeon-Sik Kim ◽

Yoon-Sub Sim ◽

Eui-Kwang Kim

Keyword(s):

Heat Transfer ◽

Liquid Metal ◽

Heat Removal ◽

Term Operation ◽

Decay Heat ◽

Removal Capacity ◽

Liquid Metal Reactor ◽

Current Design ◽

Heat Removal System ◽

Removal System

A new design concept for a decay heat removal system in a liquid metal reactor is proposed. The new design utilizes a thermosyphon to enhance the heat removal capacity and its heat transfer characteristics are analyzed against the current PSDRS (Passive Safety Decay heat Removal System) in the KALIMER (Korea Advanced LIquid MEtal Reactor) design. The preliminary analysis results show that the new design with a thermosyphon yields substantial increase of 20∼40% in the decay heat removal capacity compared to the current design that do not have the thermosyphon. The new design reduces the temperature rise in the cooling air of the system and helps the surrounding structure in maintaining its mechanical integrity for long term operation at an accident. Also the analysis revealed the characteristics of the interactions among various heat transfer modes in the new design.

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Experimental Research on Non-Condensable Gases Effects in Passive Decay Heat Removal System

Volume 3: Thermal-Hydraulics ◽

10.1115/icone24-60769 ◽

2016 ◽

Author(s):

Yang Liu ◽

Haijun Jia ◽

Li Weihua

Keyword(s):

High Pressure ◽

Heat Removal ◽

Volume Ratio ◽

Test Facility ◽

Pressurized Water Reactor ◽

Pressurized Water ◽

Decay Heat ◽

Optimizing Design ◽

Heat Removal System ◽

Removal System

Passive decay heat removal (PDHR) system is important to the safety of integral pressurized water reactor (IPWR). In small break LOCA sequence, the depressurization of the reactor pressure vessel (RPV) is achieved by the PDHR that remove the decay heat by condensing steam directly through the SGs inside the RPV at high pressure. The non-condensable gases in the RPV significantly weaken the heat transfer capability of PDHR. This paper focus on the non-condensable gas effects in passive decay heat removal system at high pressure. A series of experiments are conducted in the Institute of Nuclear and New Energy Technology test facility with various heating power and non-condensable gas volume ratio. The results are significant to the optimizing design of the PDHR and the safety operation of the IPWR.

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Experimental study on the transient response of passive decay heat removal system

Nuclear Engineering and Design ◽

10.1016/j.nucengdes.2014.09.006 ◽

2014 ◽

Vol 280 ◽

pp. 564-569 ◽

Cited By ~ 3

Author(s):

V. Vinod ◽

S. Chandramouli ◽

G. Padmakumar ◽

B.K. Nashine ◽

K.K. Rajan

Keyword(s):

Experimental Study ◽

Transient Response ◽

Heat Removal ◽

Decay Heat ◽

Heat Removal System ◽

Removal System

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Integration of functional reliability analysis with hardware reliability: An application to safety grade decay heat removal system of Indian 500MWe PFBR

Annals of Nuclear Energy ◽

10.1016/j.anucene.2008.12.004 ◽

2009 ◽

Vol 36 (4) ◽

pp. 481-492 ◽

Cited By ~ 18

Author(s):

T. Sajith Mathews ◽

A. John Arul ◽

U. Parthasarathy ◽

C. Senthil Kumar ◽

M. Ramakrishnan ◽

...

Keyword(s):

Reliability Analysis ◽

Heat Removal ◽

Decay Heat ◽

Hardware Reliability ◽

Functional Reliability ◽

Heat Removal System ◽

Removal System

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Cycle Calculations of a Small-Scale Heat Removal System With Supercritical CO2 As Working Fluid

Volume 3: Nuclear Fuel and Material, Reactor Physics and Transport Theory; Innovative Nuclear Power Plant Design and New Technology Application ◽

10.1115/icone25-66084 ◽

2017 ◽

Author(s):

Marcel Strätz ◽

Jörg Starflinger ◽

Rainer Mertz ◽

Michael Seewald ◽

Sebastian Schuster ◽

...

Keyword(s):

Power Plant ◽

Supercritical Co2 ◽

Heat Removal ◽

Working Fluid ◽

Small Scale ◽

Brayton Cycle ◽

Additional Heat ◽

Decay Heat ◽

Heat Removal System ◽

Removal System

In case of an accident in a nuclear power plant with combined initiating events, (loss of ultimate heat sink and station blackout) additional heat removal system could transfer the decay heat from the core to and diverse ultimate heat sink. On additional heat removal system, which is based upon a Brayton cycle with supercritical CO2 as working fluid, is currently investigated within an EU-funded project, sCO2-HeRo (Supercritical carbon dioxide heat removal system). It shall serve as a self-launching, self-propelling and self-sustaining decay heat removal system to be used in severe accident scenarios. Since a Brayton cycle produces more electric power that it consumes, the excess electric power can be used inside the power plant, e.g. recharging batteries. A small-scale demonstrator will be attached to the PWR glass model at Gesellschaft für Simulatorforschung GfS, Essen, Germany. In order to design and build this small-scale model, cycle calculations are performed to determine the design parameters from which a layout can be derived.

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