Late-Time Mixing Sensitivity to Initial Broadband Surface Roughness in High-Energy-Density Shear Layers

K A Flippo; F W Doss; J L Kline; E C Merritt; D Capelli; T Cardenas; B DeVolder; F Fierro; C M Huntington; L Kot; E N Loomis; S A MacLaren; T J Murphy; S R Nagel; T S Perry; R B Randolph; G Rivera; D W Schmidt

doi:10.1103/PhysRevLett.117.225001

Late-Time Mixing Sensitivity to Initial Broadband Surface Roughness in High-Energy-Density Shear Layers

Phys Rev Lett. 2016 Nov 25;117(22):225001. doi: 10.1103/PhysRevLett.117.225001. Epub 2016 Nov 23.

Authors

K A Flippo¹, F W Doss², J L Kline¹, E C Merritt¹, D Capelli³, T Cardenas³, B DeVolder⁴, F Fierro³, C M Huntington⁵, L Kot¹, E N Loomis¹, S A MacLaren⁵, T J Murphy¹, S R Nagel⁵, T S Perry¹, R B Randolph³, G Rivera³, D W Schmidt³

Affiliations

¹ Physics Division, Plasma Physics, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
² Theoretical Design Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
³ Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
⁴ Computational Physics Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
⁵ Lawrence Livermore National Laboratory, Livermore, California 94550-9234, USA.

PMID: 27925731
DOI: 10.1103/PhysRevLett.117.225001

Abstract

Using a large volume high-energy-density fluid shear experiment (8.5 cm^{3}) at the National Ignition Facility, we have demonstrated for the first time the ability to significantly alter the evolution of a supersonic sheared mixing layer by controlling the initial conditions of that layer. By altering the initial surface roughness of the tracer foil, we demonstrate the ability to transition the shear mixing layer from a highly ordered system of coherent structures to a randomly ordered system with a faster growing mix layer, indicative of strong mixing in the layer at a temperature of several tens of electron volts and at near solid density. Simulations using a turbulent-mix model show good agreement with the experimental results and poor agreement without turbulent mix.