Analysis of liquid sodium spills spreading on floor surface pertaining to sodium pool fire events in SFR cells

• Published in: Nuclear engineering and design 2020-07, Vol.363, p.110614, Article 110614
• Main Authors: Muthu Saravanan, S., Mangarjuna Rao, P., Raghupathy, S.
• Format: Article
• Language: English
• Subjects: Burning; Computer simulation; Fire protection; Fire safety; Floors; Hydrocarbon fuels; Instantaneous and continuous spills; Integral spreading model; Integrals; Liquid sodium; Mathematical models; Nuclear engineering; Nuclear fuels; Nuclear safety; Pool fires; Pool spreading; SFR safety; Sodium; Sodium cooled reactors; Sodium fire safety; Sodium pool fire; Spills; Spreading; Water spreading
• ISSN: 0029-5493; 1872-759X
• DOI: 10.1016/j.nucengdes.2020.110614

•Analyzed the spreading behavior of liquid sodium spills under accidental leak scenarios in SFR systems.•Integral model is applied for predicting dynamics of sodium spreading under pool fire conditions.•Developed model is validated with water spreading and sodium pool fire spreading test results.•Predicted the transient pool radius and maximum pool area required for sodium fire safety analysis. Analysis of postulated sodium leak events and resultant pool fire scenarios is essential in the safety evaluation of Sodium-cooled Fast Reactors (SFR). In this connection, numerical studies have been carried out to analyze the spreading characteristics of accidental liquid sodium spills on the cell floor surface under pool fire conditions in SFR systems. The dynamics of sodium pool spreading has been investigated by implementing the integral model, which is commonly employed for liquefied hydrocarbon fuel spills spreading on land or water surface by using the specific characteristics of sodium pool fire. The governing equations have been solved numerically, and the model predictions have been validated with the liquid sodium and water spreading experimental results available in the literature. The present analysis results have shown that the 1-D integral model could fairly predict the overall behaviour of sodium pool spreading, under burning conditions. The validated model has been used to evaluate liquid sodium spreading and pool formation for different leak scenarios under postulated accidental conditions in SFR. The model is useful to simulate the spreading behaviour of sodium spills with the numerical codes developed to evaluate the sodium fire safety.