3D computations of the primary coolant flow in a 1300 MW PWR vessel. Normal operation steady state and free boron plugs mixing transient simulations

Abstract:

This paper reports a R&D action based on numerical simulations and experiments on the primary coolant temperature or boron mixing capabilities in a PWR vessel. We present new numerical results performed with the Thermalhydraulic Finite Element (FE) Code N3S. The geometry taken into account represents a PWR 1300 MW PQY vessel. In these calculations the FE mesh takes into account the geometry of the lower plenum plates and columns. Two configurations have been investigated. The first one is a steady state fluid flow mixing case. The reactor is cooled by free convection and the four loops balanced in mass flow rate are in operation (full flow). The second case is a free boron plug transient case. It is related to the mixing of a clear plug pushed in the vessel when a primary coolant pump starts-up. One clear plug volume, 3 m3, have been investigated. Comparisons between these new numerical results and those obtained with the PWR 900 MW CPY vessel are presented in this paper.

Año de publicación:

1999

Keywords:

Fuente:

scopus