Preliminary experimental evaluation of thermal conductivity of ceramic pebble beds

31st UIT (Italian Union of Thermo-fluid-dynamics) Heat Transfer Conference 2013

Aquaro, D.^1 ; Frano, R. Lo^1

DICI - University of Pisa, Pisa, Italy^1

关键词: Compression force;    Compression strain;    Effective thermal conductivity;    Experimental evaluation;    Experimental rigs;    Neutron multipliers;    Nuclear fusion reactors;    Steady-state condition;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/501/1/012031/pdf
DOI  :  10.1088/1742-6596/501/1/012031

来源: IOP

【 摘 要 】

This paper illustrates the preliminary experimental tests for determining the effective thermal conductivity of ceramic pebble beds versus temperature and compression strains. Ceramic pebble beds are promising candidates to be used in breeding blankets for nuclear fusion reactor as breeder and neutron multiplier. The tests were performed with an experimental rig, built at the DICI-University of Pisa, which permits to determine the thermal conductivity of pebble beds in steady state conditions, at several temperatures and compression forces. The values of thermal conductivity of pebble beds are obtained as function of a known conductivity of an alumina disc. The assessment of the method has been performed determining the effective thermal conductivity of alumina pebbles beds of different diameters. Void fraction and compression strains are the parameters that mainly influence the variability of the thermal conductivity of the beds.