Thermal-Hydraulics: from Fundamentals to Applications

The (old) idea of the document is to connect science and technology. The (ambitious) goal is to show how the fundamental understanding and the basic research related to a scientific discipline are functional for the technology of a complex system. In the concerned case, the scientific discipline is the nuclear thermal-hydraulics or the science studying the evolution of steam-liquid mixtures and the complex system is the Nuclear Power Plant. The roadmap of the document makes reference to the history in the development of the discipline also mentioning unresolved issues in physics. Notwithstanding open questions in the fundamental understanding, the structured knowledge-basis and the adoption of engineering tools allow the operation of complex systems and the estimation of the risk. The (lack of) role of nuclear thermalhydraulics for the catastrophic events of Three Mile Island (1979), Chernobyl (1986) and Fukushima (2011) is mentioned in this context. A contribution could come from this document in understanding the benefit for the humanity and the civilization from the nuclear technology.