'A Compressible Kinematic Model for Particle Flow in Pebble Bed Reactors
Transactions of the American Nuclear Society, Vol. 101, pp. 915-916 (2009)
Granular dynamics of pebbles in a Pebble Bed Reactor (PBR) is very complex due to many body interactions as well as long range interactions that arise from stress fields. Of particular interest in a PBR is the arching or locking phenomenon, which hinders the ability of the fuel pebbles to drain out during refueling. In general, driven granular flow is governed by the geometry and external boundary conditions of silos and hoppers, and material properties such as contact friction and elasticity. Evidently, a firm understanding of the pebble flow mechanisms plays an important role for a robust design of a PBR reactor.