Next Article in Journal
Rapid Synthesis and Formation Mechanism of Core-Shell-Structured La-Doped SrTiO3 with a Nb-Doped Shell
Previous Article in Journal
Experimental Study on Artificial Cemented Sand Prepared with Ordinary Portland Cement with Different Contents
Open AccessArticle

The Effect of Particle Size on Thermal Conduction in Granular Mixtures

1
Department of Civil and Environmental Engineering, Georgia Institute of Technology, North Ave NW, Atlanta, GA 30332, USA
2
Department of Civil and Environmental Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749, Korea
*
Author to whom correspondence should be addressed.
Academic Editor: Gareth Neighbour
Materials 2015, 8(7), 3975-3991; https://doi.org/10.3390/ma8073975
Received: 20 May 2015 / Revised: 19 June 2015 / Accepted: 29 June 2015 / Published: 2 July 2015
Shredded rubber tire is a geomaterial that is potentially useful in environmental and engineering projects. Here, we study the effect of particle size ratio on the thermal conductivity of granular mixtures containing rubber tire particles. Glass beads were mixed at various volume fractions with rubber particles of varying size. The 3D network model analysis using synthetic packed assemblies was used to determine the dominant factors influencing the thermal conduction of the mixtures. Results present that mixtures with varying size ratios exhibit different nonlinear evolutions of thermal conductivity values with mixture fractions. In particular, mixtures with large insulating materials (e.g., rubber particles) have higher thermal conduction that those with small ones. This is because the larger insulating particles allow better interconnectivity among the conductive particles, thereby avoiding the interruption of the thermal conduction of the conductive particles. Similar tests conducted with natural sand corroborate the significant effect of the relative size of the insulating particles. The 3D network model identifies the heterogeneity of local and effective thermal conductivity and the influence of connectivity among conductive particles. A supplementary examination of electrical conductivity highlights the significance of local and long-range connectivity on conduction paths in granular mixtures. View Full-Text
Keywords: thermal conductivity; rubber mixture; size ratio; discrete element method; network model thermal conductivity; rubber mixture; size ratio; discrete element method; network model
Show Figures

Figure 1

MDPI and ACS Style

Lee, J.; Yun, T.S.; Choi, S.-U. The Effect of Particle Size on Thermal Conduction in Granular Mixtures. Materials 2015, 8, 3975-3991.

Show more citation formats Show less citations formats

Article Access Map by Country/Region

1
Only visits after 24 November 2015 are recorded.
Back to TopTop