Parameter studies concerning the flow behaviour of a pebble with reference to the fuel element movement in the core of the THTR 300 MWe prototype reactor

Abstract The knowledge of the pebble bed flow behaviour is of great importance for gas-cooled high temperature reactors of the pebble bed type. Comprehensive experimental investigations were carried out in this respect. After a short description of the methods of measurement the results of parameter studies with reference to the flow behaviour of a pebble bed are discussed. Various parameters of geometry are investigated as well as the influence of friction, of specific ball weight and of relative ball diameter as functions of pebble bed height. Results are plotted in form of residence spectra. From these results the flow behaviour of the THTR 300 MWe prototype reactor is predicted by interpolation.