A pre-test analysis of ATLAS SBO with RCP seal leakage using MARS code

Quang Huy Pham1, Sang Yong Lee2, Seung Jong Oh2
1 Dalat Nuclear Research Institute, Vietnam Atomic Energy Institute, 01-Nguyen Tu Luc, Dalat city, Vietnam
2 KEPCO International Nuclear Graduate School, 1456-1 Shinam-ri, Seosaeng-myeon, Ulju-gun, Ulsan, Korea

Main Article Content


The accident in Fukushima Daiichi nuclear power plants shows the important of developing coping strategies for extended station blackout (SBO) scenarios of the nuclear power plants (NPPs). Many NPPs in United State of America are applying FLEX approach as main coping strategies for extended station blackout (SBO) scenarios. In FLEX strategies, outside water injection to reactor cooling system (RCS) and steam generators (SGs) is considered as an effective method to remove residual heat and maintain the inventory of the systems during the accident. This study presents a pretest calculation using MARS code for the Advanced Thermal-hydraulic Test Loop for Accident Simulation (ATLAS) SBO experiment with RCP seal leakage scenario. In the calculation, the turbinedriven auxiliary feed water pumps (TDAFPs) are firstly used after SBO initiation. Then, the outside cooling water injection method is used for long term cooling. In order to minimize operator actions and satisfy requirements of APR1400 emergency operation procedure (EOP), the SGs Atmospheric Dump Valve (ADV) opening ratio, auxiliary feed water (AFW) and outside cooling water injection flow rates were investigated to have suitable values. The analysis results would be useful for performing the experiment to verify the APR 1400 extended SBO optimum mitigation strategy using outside cooling water injection.

Article Details


[1] NEI 12-06, “Diverse and Flexible Coping Strategies (FLEX) Implementation Guide,” Rev. 0, 2012.
[2] Y. S. Kim et al, “Commissioning of the ATLAS Thermal Hydraulic Integral Test Facility,” Annals of Nuclear Energy, 35, 1791, 2008.
[3] M. Ishii, et al., “The three level scaling approach with application to the Purdue University multi-dimensional integral test assembly (PUMA),” Nuclear Engineering and Design, 186, 177–211, 1998.
[4] K.H. Kang, et al., “Detailed Description Report of ATLAS Facility and Instrumentation,” KAERI/TR-4316/2011, Korea Atomic Energy Research Institute, 2011.
[5] KAERI, MARS code manual, KAERI/TR-2812/2004, 2009.
[6] J.R. Hwang, S.J. Oh, “Developing Optimal Procedure of Emergency Outside Cooling Water Injection for APR1400 Extended SBO Scenario Using MARS Code,” KNS, 2013.
[7] Korea Hydro & Nuclear Power Co., Ltd., Shin-Kori Unit 3,4 NPP, “Station Blackout Emergency Operation Procedure, EOP-07, Rev. 0, 2011.
[8] Westinghouse Electric Company LLC, “Reactor Coolant Pump Type R01 Technical Manual,” Volume 1, 9-181 -Z-431 -N01C, 2011.
[9] J.R. Hwang, “Use of Emergency Outside Cooling Water Injection for APR1400 Extended SBO Scenario,” Master thesis, Kepco International Nuclear Graduate School (KINGS), 2013.