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One dimensional heat conductivity exponent from random collision model

J. M. Deutsch·Onuttom Narayan
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Abstract

We study numerically the thermal conductivity coefficient $κ$ as a function of system length $L$ for several different quasi one dimensional models: classical gases of hard spheres with both longitudinal and transverse degrees of freedom. We introduce a model that is ergodic and highly chaotic but also conserves energy and momentum, and is very useful because it shows scaling even at small system sizes. We find that $κ\sim L^α$ over more than two decades, with $α$ very close to the analytical prediction of 1/3.

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J. M. Deutsch, Onuttom Narayan. 2003-01-13. One dimensional heat conductivity exponent from random collision model. https://doi.org/10.1103/physreve.68.010201

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