INVESTIGATION OF PRESSURE DROP FOR FLUID FLOW THROUGH POROUS MEDIA: APPLICATION TO A PEBBLE-BED REACTOR

The present studied Pebble-Bed Reactor is a light-water cooled reactor that consists of millions of Micro-Fuel Elements, and the TRISO-coated fuel particles(MFE) fill the fuel assembly disorderly and form a porous media with internal heat source. Papers on porous media continue to be published at the rate of about 150 per year and the domain of application is wide spread, ranging from chemical particle beds, mass separator units, debris beds, soil investigations, heat pipes and fluidized beds etc. In this paper, investigation is performed on the press drop under conditions of both single-phase and two-phase flow through porous media. Large number of relations are studied and the relational expressions, which generalize the available data of experiments, are suggested for pressure drop calculation in a pebble bed of spheres at random distribution. Finally, the relational expressions are applied to analyze the flow characteristics of the Pebble-Bed Reactor, such as the influence of pressure on two phase friction factor in the core etc.