Status and future challenges of liquid metal cooled reactor thermal-hydraulics

Liquid metal cooled reactors are envisaged to play an important role in the future of nuclear energy production because of their possibility to use natural resources efficiently and to reduce the volume and lifetime of nuclear waste. Typically, sodium and lead(-alloys) are envisaged as coolants for such reactors. Obviously, in the development of these reactors, thermal-hydraulics is recognized as a key challenge for design and safety purposes. This paper will discuss the development status of liquid metal cooled reactor thermal-hydraulics. In addition, the main challenges for future developments will be indicated. Firstly, the technological and safety challenges will be discussed. However, in order address these issues, numerical analysis and associated experimental validation are required. Therefore, emphasis will be put on the important experimental and numerical challenges.