Heat conduction and diffusion of hard disks in a narrow channel

Adam Lipowski; Dorota Lipowska

doi:10.1103/physreve.75.052201

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arXiv · cond-mat/0610309

Heat conduction and diffusion of hard disks in a narrow channel

Adam Lipowski·Dorota Lipowska

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Abstract

Using molecular dynamics we study heat conduction and diffusion of hard disks in one dimensional narrow channels. When collisions preserve momentum the heat conduction $κ$ diverges with the number of disks $N$ as $κ\sim N^α$ $(α\approx 1/3)$. Such a behaviour is seen both when the ordering of disks is fixed ('pen-case' model), and when they can exchange their positions. Momentum conservation results also in sound-wave effects that enhance diffusive behaviour and on an intermediate time scale (that diverges in the thermodynamic limit) normal diffusion takes place even in the 'pen-case' model. When collisions do not preserve momentum, $κ$ remains finite and sound-wave effects are absent.

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Adam Lipowski, Dorota Lipowska. 2007-05-20. Heat conduction and diffusion of hard disks in a narrow channel. https://doi.org/10.1103/physreve.75.052201

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