Performance evaluation of nuclear fuel in a reactor based on the CAREM 25

Nuclear energy has been proven as a viable option for strengthening a power grid, and the expansion of the Brazilian nuclear programme is becoming a reality in light of new reactor projects currently in the licensing and/or construction stage in the country. The object of study in this paper is a small modular reactor (SMR) based on the CAREM 25 Reactor designed in Argentina that represents an innovation in nuclear reactor research in Latin America and belongs to the category of advanced reactors. It is a reduced-size Pressurized Water Reactor (PWR) with integrated primary and secondary circuits, passive and redundant safety systems, light water cooling, and a power output of 25 MW. In this study, the behaviour of certain safety parameters related to a nuclear fuel rod operating at high burnup is evaluated, considering different types of coatings commonly used in the country. The aspects addressed are related to plant operational safety and fuel integrity, such as fuel centreline temperature, cladding surface temperature, oxide layer thickness on the rod surface, and hydrogen concentration in the cladding. The results obtained show that the tool used for simulating the performance of fuel rods in conventional PWR reactors, such as the FRAPCON line, can be applied to smaller modular reactors as well, along with the feasibility of using well-established coatings in the country.