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arXiv · 1910.07490

First-order contributions to the partial temperatures in binary granular suspensions at low density

Rubén Gómez González·Vicente Garzó
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Abstract

The Boltzmann kinetic equation is considered to evaluate the first-order contributions $T_i^{(1)}$ to the partial temperatures in binary granular suspensions at low density. The influence of the surrounding gas on the solid particles is modeled via a drag force proportional to the particle velocity plus a stochastic Langevin-like term. The Boltzmann equation is solved by means of the Chapman--Enskog expansion around the local version of the reference homogeneous base state. To first-order in spatial gradients, the coefficients $T_i^{(1)}$ are computed by considering the leading terms in a Sonine polynomial expansion. In addition, the influence of $T_i^{(1)}$ on the first-order contribution $\zeta^{(1)}$ to the cooling rate is also assessed. Our results show that the magnitude of both $T_i^{(1)}$ and $\zeta^{(1)}$ can be relevant for some values of the parameter space of the system.

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Rubén Gómez González, Vicente Garzó. 2019-10-16. First-order contributions to the partial temperatures in binary granular suspensions at low density. https://arxiv.org/abs/1910.07490

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