Flexblue® Underwater Reactor: Introduction To The Concept And To The Passive Safety Strategy For A Steam Generator Tube Rupture Accident


Nuclear power plants (NPPs), which are operating and under construction are large-scale reactors with an electrical output around 1,000 MWe. These plants do not address the needs of developing countries or archipelagos, where the grids are smaller and the investment capacities are limited. For this reason, many nuclear designers develop Small Modular Reactors (SMRs), which can generate electrical output below 300 MWe. DCNS offers a FLEXBLUE® as a solution to the problem. FLEXBLUE® is a subsea-based Small Modular Reactor and fully transportable nuclear module. A FLEXBLUE® module is designed for the single purpose of delivering electricity to the grid. Its power output is 160 MWe and is sent to the grid by submarine cables. The goal of this study is to work out an innovative strategy to handle a steam generator tube rupture with passive systems only, without releasing any radioactive elements to the environment, and without flooding the containment.


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