Pool inlet LOCA safety analysis in support of the emergency core spray system success criteria development of the PULSTAR research reactor

• Published in: Nuclear engineering and design 2023-03, Vol.403, p.112163, Article 112163
• Main Authors: Farag, Asmaa S., Alzahrani, Yahya A., Diaconeasa, Mihai A.
• Format: Article
• Language: English
• ISSN: 0029-5493; 1872-759X
• DOI: 10.1016/j.nucengdes.2023.112163

•Success criteria are developed to inform the design of an emergency core spray system at the PULSTAR research reactor.•The safety analysis results are used to support the licensing amendment process to increase the power from 1 MWth to 2 MWth.•The parametric study can be used to for future design changes to increase the power to even higher levels. The PULSTAR pool-type research reactor has been operating at power levels up to 1 MWth since initial criticality in 1972 on the North Carolina State University (NCSU) campus. At the current power level, there is no need for an emergency core cooling system to provide additional cooling during abnormal conditions since, at this power level, the peak cladding temperature (PCT) cannot reach the maximum allowable temperature. The range of experiments possible could be extended if the reactor is to be licensed by the U.S. Nuclear Regulatory Commission (NRC) to run up to higher power levels. However, the maximum allowable PCT at higher power levels could be exceeded during abnormal conditions. In this study, a best estimate transient simulation model is used to inform the design of an emergency core spray system to the PULSTAR research reactor. We provide the analysis results of the most limiting scenario of a pool inlet large break loss of coolant accident (LOCA) while operating at higher power levels. Currently, NCSU’s research reactor program is developing a plan to increase the operating power to 2 MWth, thus most of the analysis performed in this paper is prepared at 2 MWth. In addition, a parametric study was carried out to obtain the maximum achievable operating power by having the emergency core spray system installed with the current coolant system arrangement.