Numerical modelling for the effective thermal conductivity of lithium meta titanate pebble bed with different packing structures

摘要

The effective thermal conductivity (k(eff)) of lithium meta-titanate (Li2TiO3) pebble beds is an important parameter for the design and analysis of IN LLCB TBM (Indian Lead Lithium Ceramic Breeder Test Blanket Module). The k(eff) of Li2TiO3 pebble beds under stagnant helium gas have been determined numerically using different uniform packing structures and random close packing (RCP) structures. The uniform packing structures of Li2TiO3 pebble bed are modelled by using the simple cubic, body centered cubic and face centered cubic arrangement. The packing structure of the RCP bed of Li2TiO3 pebbles is generated with the discrete element method (DEM) code. k(eff) of Li2TiO3 pebble beds with different packing fractions have been reported as function of temperature; k(eff) of the RCP Li2TiO3 pebble bed is compared with reported experimental results from literature. The numerically determined k(eff) of the Li2TiO3 pebble bed agrees reasonably well with the experimental data. (C) 2016 Elsevier B.V. All rights reserved.