Experimental Investigation of Pebble Flow Dynamics using Radioactive Particle Tracking Technique in a Scaled-Down Pebble Bed Modular Reactor (PBMR)


The Pebble Bed Modular Reactor (PBMR) is a type of very-high-temperature reactor (VHTR) that is conceptually very similar to moving bed reactors used in the chemical and petrochemical industries. In a PBMR core, nuclear fuel is in the form of pebbles and moves slowly under the influence of gravity. In this work, an integrated experimental and computational study of granular flow in a scaled-down cold flow PBMR was performed. A continuous pebble re-circulation experimental set-up, mimicking the flow of pebbles in a PBMR was designed and developed. An experimental investigation of pebble flow dynamics in a scaled down test reactor was carried out using a non-invasive radioactive particle tracking (RPT) technique that used a cobalt-60 based tracer to mimic pebbles in terms of shape, size and density. A cross-correlation based position reconstruction algorithm and RPT calibration data were used to obtain results about Lagrangian trajectories, the velocity field, and residence time distributions. The RPT technique results a serve as a benchmark data for assessing contact force models used in the discrete element method (DEM) simulations.


Chemical and Biochemical Engineering


The authors acknowledge the financial support provided by Department of Energy (DOE) Nuclear Energy Research Initiative (NERI) project (NERI-08-043).

Keywords and Phrases

Finite Difference Method; Flow of Solids; Fluidized Beds; Granular Materials; High Temperature Reactors; Pebble Bed Reactors; Radioactive Tracers; Radioactivity; Residence Time Distribution; Velocity; Computational Studies; Contact Force Models; Experimental Investigations; Lagrangian Trajectories; Moving Bed Reactors; Petrochemical Industry; Position Reconstruction; Radioactive Particle Tracking; Pebble Bed Modular Reactors

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Article - Journal

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© 2016 Elsevier, All rights reserved.

Publication Date

01 Jun 2016