Use of passive cooling systems in generation IV nuclear reactors for core decay heat removal and containment cooling
ENGLISH ABSTRACT: The Pebble Bed Modular Reactor (PBMR) concept evolved from a German high temperature helium-cooled reactor design with ceramic spherical fuel pebbles. The removal of parasitic heat between the reactor core and concrete citadel is facilitated through the Reactor Cavity Cooling System (RCCS). The RCCS primary function is to passively maintain the cavity temperature within a required range. This is in order to provide protection to the concrete structures surrounding the reactor and also, during loss of coolant accident operating conditions, to transport parasitic heat from the reactor to the environment. Several Generation IV reactor designs incorporate passive safety systems. The main objective of this study is to familiarise the reader with specific “innovative” nuclear reactor designs and discuss the different passive safety systems employed in these designs for core decay heat removal and containment cooling systems. A table is given comparing the type, thermal efficiency, fuel, coolant and passive safety systems employed by each reactor to those of the PBMR.