Blast dynamics in a dissipative gas

Abstract

The blast caused by an intense explosion has been extensively studied in conservative fluids, where the Taylor-von Neumann-Sedov hydrodynamic solution is a prototypical example of self-similarity driven by conservation laws. In dissipative media however, energy conservation is violated, yet a distinctive self-similar solution appears. It hinges on the decoupling of random and coherent motion permitted by a broad class of dissipative mechanisms. This enforces a peculiar layered structure in the shock, for which we derive the full hydrodynamic solution, validated by a microscopic approach based on Molecular Dynamics simulations. We predict and evidence a succession of temporal regimes, as well as a long-time corrugation instability, also self-similar, which disrupts the blast boundary. These generic results may apply from astrophysical systems to granular gases, and invite further cross-fertilization between microscopic and hydrodynamic approaches of shockwaves.

5 pages, to appear in Physical Review Letters

References in corpus (3)

• Dynamics of Freely Cooling Granular Gases
• Shock Propagation in Granular Flow Subjected to an External Impact
• Evolution and stability of shock waves in dissipative gases characterized by activated inelastic collisions

Cited by in corpus (6)

• Blast in a One-Dimensional Cold Gas: From Newtonian Dynamics to Hydrodynamics
• The Taylor-von Neumann-Sedov blast-wave solution: comparisons with microscopic simulations of a one-dimensional gas
• Microscopic origin of self-similarity in granular blast waves
• Shock propagation in locally driven granular systems
• Blast waves in two and three dimensions: Euler versus Navier Stokes equations
• Extreme dynamics and relaxation of quantum gases: A hydrodynamic approach