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arXiv · 2105.01972

Mpemba effect in anisotropically driven inelastic Maxwell gases

Apurba Biswas·V. V. Prasad·R. Rajesh
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Abstract

Through an exact analysis, we show the existence of Mpemba effect in an anisotropically driven inelastic Maxwell gas, a simplified model for granular gases, in two dimensions. Mpemba effect refers to the couterintuitive phenomenon of a hotter system relaxing to the steady state faster than a cooler system, when both are quenched to the same lower temperature. The Mpemba effect has been illustrated in earlier studies on isotropically driven granular gases, but its existence requires non-stationary initial states, limiting experimental realisation. In this paper, we demonstrate the existence of the Mpemba effect in anisotropically driven granular gases even when the initial states are non-equilibrium steady states. The precise conditions for the Mpemba effect, its inverse, and the stronger version, where the hotter system cools exponentially faster are derived.

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Apurba Biswas, V. V. Prasad, R. Rajesh. 2021-05-05. Mpemba effect in anisotropically driven inelastic Maxwell gases. https://doi.org/10.1007/s10955-022-02891-w

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