Single-phase, Two-phase and Supercritical Natural Circulation Systems

Dr Pallippattu Krishnan Vijayan is currently working as a Raja Ramanna Fellow at the Bhabha Atomic Research Centre (BARC) and his research focuses on natural circulation based passive safety systems for advanced reactors. Dr Vijayan, a chemical engineer from the University of Calicut joined BARC after completing the training course in nuclear science engineering conducted by BARC. He received his PhD from the Department of Energy Systems Engineering, IIT Bombay in 1989. A Distinguished Scientist, Dr Vijayan served at BARC in various positions such as group leader, head, thermal hydraulics section, head reactor engineering division and Director, Reactor Design and Development Group. He has worked nearly four decades in the field of thermal hydraulics of nuclear reactors and his specific field of expertise is natural circulation based passive safety systems. He played a key role in the thermal hydraulic design of thorium based Advanced Heavy Water Reactor (AHWR) and established large scale integral test facilities for its thermal hydraulic design validation. He participated in several International Atomic Energy Agency (IAEA) coordinated research projects and bilateral research projects like Indo-Italian, Indo-German, Indo-UK, Indo-Korea and AERB-US NRC. He was one of the experts invited by IAEA to formulate a training course on ‘Natural circulation phenomena and passive safety systems for advanced water cooled reactors’ and is a lecturer for this IAEA training course since 2004. 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." Naveen Kumar works in the Bhabha Atomic Research Centre at Trombay, Mumbai, India.

• 1. Natural circulation loops—advantages, challenges, and classification2. Review of applications of natural circulation systems3. Governing differential equations for natural circulation systems4. Steady-state and transient performance of single-phase natural circulation systems5. Steady-state and transient analysis of two-phase natural circulation systems6. Steady-state and transient analysis of supercritical natural circulation systems7. Instabilities in natural circulation systems8. Stability analysis of natural circulation systems9. Modeling of instabilities in multichannel natural circulation boiling water reactors10. Design of natural circulationbased systems11. Coupled natural circulation systems12. Scaling philosophy for natural circulation systems13. Thermosyphon heat transport devices