Author(s)

A. Horvat, I. Kljenak & J. Mam

Abstract

A reactor pressure vessel lower plenum retention problem was studied to determine external cooling margins of the plenum walls. The accumulated melt was modelled as an incompressible fluid with internal volumetric heat generation in a rectangular cavity. A Smagorinsky type of large-eddy simulation model for buoyancy flows was implemented. Because of uncertainty about upper wall thermal boundary conditions, isothermal and adiabatic boundary conditions were used to assess heat transfer margins (Nusselt number) at each boundary of the simulation domain. It was found in both calculated cases that the Nusselt number is lowest at the bottom of the simulation domain and increases

Keywords