Direct Numerical Simulation of the Thermal Effects in Plasma/Turbulence Interaction

The thermal effects of laser–induced plasma on isotropic turbulence are studied using direct numerical simulation. Laminar and turbulent simulations are conducted. For the laminar simulations, a tear–drop shaped blast wave propagates into the background becoming spherical in time. Shock radius and jumps in fluid properties at the shock front are compared to experiment. Both short and long time behavior of the plasma is studied. At short times, baroclinic vorticity is generated as a consequence of propagation of the curved shock through the domain. At long times, the flow field forms toroidal vortex rings, as observed in experiments. For the turbulent simulations, turbulence levels get enhanced in regions of compression across the blast wave and suppressed in regions of expansion in the plasma core.