Tensor Temperature and Shockwave Stability in a Strong Two-Dimensional Shockwave

Wm. G. Hoover; Carol G. Hoover

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arXiv · 0905.1913

Tensor Temperature and Shockwave Stability in a Strong Two-Dimensional Shockwave

Wm. G. Hoover·Carol G. Hoover

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Abstract

The anisotropy of temperature is studied here in a strong two-dimensional shockwave, simulated with conventional molecular dynamics. Several forms of the kinetic temperature are considered, corresponding to different choices for the local instantaneous stream velocity. A local particle-based definition omitting any "self" contribution to the stream velocity gives the best results. The configurational temperature is not useful for this shockwave problem. Configurational temperature is subject to a shear instability and can give local negative temperatures in the vicinity of the shock front. The decay of sinusoidal shockfront perturbations shows that strong two-dimensional planar shockwaves are stable to such perturbations.

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Wm. G. Hoover, Carol G. Hoover. 2009-06-24. Tensor Temperature and Shockwave Stability in a Strong Two-Dimensional Shockwave. https://arxiv.org/abs/0905.1913

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