NATURAL CIRCULATION TEST CAMPAIGN ON HERO-2 BAYONET TUBES TEST SECTION

Innovative nuclear systems, such as the SMR and Gen-IV reactors, require relatively new approaches to accomplish the function of heat removal to achieve the goal of safety and economics, both in operative and accidental conditions. The heat exchanger compactness and operability in natural circulation are of great importance for such systems. ENEA in collaboration with POLIMI and SIET is leading some studies on innovative heat exchangers within the framework of a National Research Program funded by the Italian Minister of Economic Development. The SIET laboratories in Piacenza, leader in testing and development of innovative components and systems, hosted an experimental campaign to characterize a DHR system working in natural circulation with HERO-2 test section; a bayonet tubes heat exchanger composed by two parallel tubes. The natural circulation tests conducted, even in presence of non-condensable gas, have allowed the creation of a valuable database for the characterization of the heat exchange capability in passive accidental conditions, useful for the qualification of computer codes supporting the design and safety analysis of innovative reactors. The paper presents the test campaign carried-out on HERO-2.