Severe Accidents in Nuclear Reactors

Arun Kumar Nayak is the Outstanding Scientist and Head of the Thermal Hydraulics Section of Bhabha Atomic Research Centre and a Professor at Hombi Bhabha National Institute in Mumbai, India. He is a graduate in Mechanical Engineering from NIT, Rourkela, India, and joined the Reactor Design and Development Group in BARC in 1990 after completing the Orientation Course in Nuclear Engineering from the BARC Training School in Mumbai, India. He obtained his PhD in Nuclear Engineering from Tokyo Institute of Technology, Japan, and has worked at the Interfaculty Reactor Institute of the Technical University Delft, as well as in the Nuclear Power Safety Division of the Royal Institute of Technology, in Stockholm as a Post-doc Scientist. He has also worked at Institute of Nuclear Energy (IKE) in the University of Stuttgart under the DST-DAAD programme. He has received several awards and is a Fellow of Maharashtra Academy of Science and Indian National Academy of Engineering. He has published more than 350 papers in academic journals and conferences, and is an Associate Editor of the journals “Computational Thermal Sciences” and “Frontiers in Energy Research – Nuclear Energy” and is a member of the editorial board of “Life Cycle Reliability and Safety Engineering." Parimal Pramod Kulkarni, a Chemical Engineering Graduate from Institute of Chemical Technology, Mumbai, India, joined Reactor Design and Development Group in BARC in 2005 after completing his masters in Chemical Engineering from Indian Institute of Technology, Kanpur. He obtained his PhD in Engineering Sciences from Homi Bhabha National Institute, Mumbai, India, in year 2015. He has also worked at Institute of Nuclear Energy (IKE), University of Stuttgart during 2008-09 in the field of debris bed coolability. He has received the DAE Young Engineer Award, 2012 and group achievement award in 2015. He has published more than 50 papers in academic Journals and Conferences. Currently he is working as Scientific Officer in Thermal Hydraulics Section, Reactor Engineering Division, BARC. He has done extensive research in the field of severe accident management which has contributed towards safety enhancement of Indian Advanced Heavy Water and Pressurized Heavy Water Reactors.

• 1. Introduction2. Progression of severe accidents in Water Cooled Reactors3. Experiments with high temperature corium stimulants4. Corium coolability in PHWRs: In-vessel retention5. Numerical Modelling of In-vessel Retention in PHWRs6. Corium coolability in ex-vessel core catcher7. Numerical modelling of ablation of sacrificial material in ex-vessel core catcher8. Fuel coolant interaction9. Debris bed coolability10. Conclusions