PWR core safety analysis with 3-dimensional methods

In this paper, an overview of AREVA's broad application experience as well as the broad validation base of its code systems is given. The importance and necessity of the comprehensive 3-dimensional methodology is illustrated by example analyses of a rod ejection accident and an 'inadvertent opening of the pressurizer safety valve' transient. The examples refer to the safety criteria pellet averaged fuel enthalpy, fast fuel enthalpy rise, number of fuel assemblies in film boiling and the maximum fuel temperature and illustrate, how 3D-methods provide evidence of bigger safety margins or archive more reliable results.