Prospective for nuclear thermal hydraulics created by ongoing and new Networks

The purpose of the present article is to introduce the FONESYS, SILENCE and CONUSAF projects run by some of the leading organizations working in the nuclear sector. The FONESYS members are developers of some of the major System Thermal-Hydraulic (SYS-TH) codes adopted worldwide, whereas the SILENCE members own and operate important thermal-hydraulic experimental facilities. The two networks work in a cooperative manner and have at least one meeting per year where experts of the highest level in the areas of thermal-hydraulic codes development and experimentation are gathered. The FONESYS members address various topics such as hyperbolicity and numerics in SYS-TH codes, 3-field modeling, transport of interfacial area, 3D modeling, scaling of thermal-hydraulic phenomena, two-phase critical flow (TPCF), critical heat flux (CHF), and others. As part of the working modalities, some numerical benchmarks were proposed and successfully conducted by the network addressing some of the most relevant topics selected by the FONESYS members (i.e. code developers). On the other hand, SILENCE addresses topics such as current measurement needs and main gaps for further SYS-TH and CFD codes development and validation, working on the identification of similar and counterpart tests in Integral Tests Facilities (including containment thermal-hydraulics) to be possibly conducted on Members’ test facilities, but also dealing with the scaling issue and other subjects. Furthermore, SILENCE organized a “Specialists Workshop on Advanced Instrumentation and Measurement Techniques for Nuclear Reactor Thermal-Hydraulics (SWINTH)” which was held in Italy on June 2016. A second edition of the Workshop, namely SWINTH-2019, will be held in Italy in 2019 under the umbrella of the OECD/NEA/CSNI/WGAMA. Recently a new initiative is being taken by launching an international consortium of nuclear thermal-hydraulics code users, the CONUSAF. The main idea is to enhance the interactions between the users of computational tools in nuclear TH, noticeably including SYS-TH and CFD codes, the code developers and the experimentalists. The proposed initiative is expected to make a positive impact on the entire ecosystem by pursuing the characterization of the current code limitations and capabilities, analyzing and addressing issues raised by the users and promoting common R&D efforts on topics of high relevance.