Modeling of the depressurisation induced by a pipe rupture in the primary circuit of a nuclear plant

The safety analysis of Pressurised Water Reactors is based on the assessment of the consequences of a hypothetical Loss Of Coolant Accident. The accident supposes that a break occurs on a pipe of the primary circuit. A depressurisation wave propagates from the break through the entire primary circuit, then the circuit empties progressively in diphasic regime. The geometry of the primary circuit is simplified and represented with a pipe-model to be able to simulate the accident in the entire circuit. After a presentation of the geometry and the numerical model, the hydraulic consequences of the LOCA are analysed.