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arXiv · 1407.4767

Shear-bulk coupling in nonconformal hydrodynamics

Gabriel S. Denicol·Wojciech Florkowski·Radoslaw Ryblewski·Michael Strickland
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Abstract

We compute the temporal evolution of the pressure anisotropy and bulk pressure of a massive gas using second-order viscous hydrodynamics and anisotropic hydrodynamics. We then compare our results with an exact solution of the Boltzmann equation for a massive gas in the relaxation time approximation. We demonstrate that, within second-order viscous hydrodynamics, the inclusion of the full set of kinetic coefficients, particularly the shear-bulk couplings, is necessary to properly describe the time evolution of the bulk pressure. We also compare the results of second-order hydrodynamics with those obtained using the anisotropic hydrodynamics approach. We find that anisotropic hydrodynamics and second-order viscous hydrodynamics including the shear-bulk couplings are both able to reproduce the exact evolution with comparable accuracy.

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Gabriel S. Denicol, Wojciech Florkowski, Radoslaw Ryblewski, Michael Strickland. 2014-10-15. Shear-bulk coupling in nonconformal hydrodynamics. https://doi.org/10.1103/physrevc.90.044905

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