Thermal conductivity of porous aggregates

Abstract

$Context.$ The thermal conductivity of highly porous dust aggregates is a key parameter for many subjects in planetary science; however, it is not yet fully understood. $Aims.$ In this study, we investigate the thermal conductivity of fluffy dust aggregates with filling factors of less than $10^{-1}$. $Methods.$ We determine the temperature structure and heat flux of the porous dust aggregates calculated by $N$-body simulations of static compression in the periodic boundary condition. $Results.$ We derive an empirical formula for the thermal conductivity through the solid network $k_{\mathrm{sol}}$ as a function of the filling factor of dust aggregates $\varphi$. The results reveal that $k_{\mathrm{sol}}$ is approximately proportional to ${\varphi }^2$, and the thermal conductivity through the solid network is significantly lower than previously assumed. In light of these findings, we must reconsider the thermal histories of small planetary bodies.

4 pages, 4 figures. Accepted for publication in Astronomy & Astrophysics

References in corpus (4)

• Rocky Planetesimal Formation via Fluffy Aggregates of Nanograins
• Experimental study on compression property of regolith analogues
• Collisions between sintered icy aggregates
• Ejection of Chondrules from Fluffy Matrices

Cited by in corpus (8)

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• Heat transfer in granular media with weakly interacting particles
• Interpebble contact radius in a comet nucleus
• Interparticle normal force in highly porous granular matter during compression