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Articles you may be interested inObservation and modeling of mixing-layer development in high-energy-density, blast-wave-driven shear flowa) Phys. Plasmas 21, 056306 (2014); 10.1063/1.4872223The high-energy-density counterpropagating shear experiment and turbulent self-heating Phys. Plasmas 20, 122704 (2013); 10.1063/1.4839115 Simulations of material mixing in laser-driven reshock experiments Phys. Plasmas 20, 022309 (2013); 10.1063/1.4793443 Experiment on the mass-stripping of an interstellar cloud in a high Mach number post-shock flowa)Radiographic data from a novel and highly successful high energy density Kelvin-Helmholtz ͑KH͒ instability experiment is presented along with synapses of the theory and simulation behind the target design. Data on instability growth are compared to predictions from simulation and theory. The key role played by baroclinic vorticity production in the functioning of the target and the key design parameters are also discussed. The data show the complete evolution of large distinct KH eddies, from formation to turbulent break-up. Unexpectedly, low density bubbles comparable to the vortex size are observed forming in the free-stream region above each vortex at late time. These bubbles have the appearance of localized shocks, possibly supporting a theoretical fluid dynamics conjecture about the existence of supersonic bubbles over the vortical structure ͓transonic convective Mach numbers, D. Papamoschou and A. Roshko, J. Fluid Mech. 197, 453 ͑1988͔͒ that support localized shocks ͑shocklets͒ not extending into the free stream ͑P. E. Dimotakis, Proceedings of the 22nd Fluid Dynamics, Plasma Dynamics and Lasers Conference, 1991, Paper No. AIAA 91-1724͒. However, it is also possible that these low density bubbles are the result of a cavitationlike effect. Hypothesis that may explain the appearance of low density bubbles will be discussed.

A laser initiated experiment is described in which an unstable plasma shear layer is produced by driving a blast wave along a plastic surface with sinusoidal perturbations. In response to the vorticity deposited and the shear flow established by the blast wave, the interface rolls up into large vortices characteristic of the Kelvin-Helmholtz instability. The experiment used x-ray radiography to capture the first well-resolved images of Kelvin-Helmholtz vortices in a high-energy-density plasma.

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A drill-foil thermocouple system is developed for measuring the temperature distribution along the cutting edges of a drill. The system is simple to implement, and it does not suffer the problems experienced by previously developed methods. Experiments show that the method is accurate, produces repeatable measurements, and is sensitive to the drilling conditions, including the speed, feed, and drill geometry.