NEA Steam Explosion Resolution for Nuclear Applications (SERENA) Project

The NEA Co-ordinated Programme on Steam Explosion Resolution for Nuclear Applications (SERENA) was established to assess the capabilities of the current generation of fuel-coolant interaction (FCI) computer codes to predict steam explosion-induced loads in reactor situations. One of the main findings of this programme was that in-vessel FCI would not challenge the integrity of the nuclear reactor containment but that this scenario could not be ruled out for ex-vessel FCI.

The NEA SERENA Joint Project has therefore been set up to resolve any uncertainties on these issues. It is planned to achieve this by performing a limited number of focused tests with advanced instrumentation to examine a large spectrum of ex-vessel melt compositions and conditions. In parallel, analytical work will be carried out to bring the code capabilities to a sufficient level that they may be used in reactor case analyses. The objective of the experimental programme is threefold:

These goals will be achieved by using the complementary features of the TROI (KAERI) and KROTOS (CEA) corium facilities, including fitness-for-purpose oriented analytical activities. KROTOS is more suited for investigating the intrinsic FCI characteristics in a one-dimensional geometry. TROI is more suited for testing the FCI behaviour of these materials in reactor-like conditions by having more mass and multi-dimensional melt water interaction geometry. The validation of models using KROTOS data and the verification of code capabilities to calculate more reactor-oriented situations simulated in TROI will strengthen confidence in code applicability to reactor FCI scenarios.

At the end of 2011 the six tests planned in the TROI facility and five out of the six tests planned in the KROTOS facility have been performed.

In parallel to the experiment the analytical working group of the project has prepared an outcome document describing the state of the knowledge regarding the main phenomena involved in steam explosion (jet break-up, melt mass and void in mixture, melt solidification during premixing and explosion phase) and has organising a reactor exercise.

A Concluding Seminar of the SERENA Project was held from 5 to 7 November 2012, hosted by CEA in Cadarache, France; It attracted 75 participants from 13 countries. 40 presentations were given covering the experimental results of SERENA program, complementary experimental results, phenomenology and model development, lessons learned from the reactor safety point of view and perspectives on the Main Conclusion of SERENA Program. The conclusion of this Seminar prepared by the Session Chair together with the final summary integration report of this project will be issued in 2013 as public CSNI report.

Participating countries

Belgium, Canada, Finland, France, Germany, Japan, Republic of Korea, Slovenia, Sweden, Switzerland, United States.

Project Period

October 2007 to March 2012


EUR 2.6 million

Related links

Last reviewed: 21 October 2013