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Title: Wavelet analysis methods for radiography of multidimensional growth of planar mixing layers

Abstract

The counter-propagating shear campaign is examining instability growth and its transition to turbulence in the high-energy-density physics regime using a laser-driven counter-propagating flow platform. In these experiments, we observe consistent complex break-up of and structure growth in a tracer layer placed at the shear flow interface during the instability growth phase. We present a wavelet-transform based analysis technique capable of characterizing the scale- and directionality-resolved average intensity perturbations in static radiographs of the experiment. This technique uses the complete spatial information available in each radiograph to describe the structure evolution. We designed this analysis technique to generate a two-dimensional power spectrum for each radiograph from which we can recover information about structure widths, amplitudes, and orientations. The evolution of the distribution of power in the spectra for an experimental series is a potential metric for quantifying the structure size evolution as well as a system’s evolution towards isotropy.

Authors:
;  [1]
  1. Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
Publication Date:
OSTI Identifier:
22597906
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 87; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AMPLITUDES; ENERGY DENSITY; IMAGES; INSTABILITY; INTERFACES; LASERS; LAYERS; MIXING; PERTURBATION THEORY; SPECTRA; TURBULENCE; TWO-DIMENSIONAL CALCULATIONS; WIDTH

Citation Formats

Merritt, E. C., E-mail: emerritt@lanl.gov, and Doss, F. W.. Wavelet analysis methods for radiography of multidimensional growth of planar mixing layers. United States: N. p., 2016. Web. doi:10.1063/1.4955097.
Merritt, E. C., E-mail: emerritt@lanl.gov, & Doss, F. W.. Wavelet analysis methods for radiography of multidimensional growth of planar mixing layers. United States. doi:10.1063/1.4955097.
Merritt, E. C., E-mail: emerritt@lanl.gov, and Doss, F. W.. 2016. "Wavelet analysis methods for radiography of multidimensional growth of planar mixing layers". United States. doi:10.1063/1.4955097.
@article{osti_22597906,
title = {Wavelet analysis methods for radiography of multidimensional growth of planar mixing layers},
author = {Merritt, E. C., E-mail: emerritt@lanl.gov and Doss, F. W.},
abstractNote = {The counter-propagating shear campaign is examining instability growth and its transition to turbulence in the high-energy-density physics regime using a laser-driven counter-propagating flow platform. In these experiments, we observe consistent complex break-up of and structure growth in a tracer layer placed at the shear flow interface during the instability growth phase. We present a wavelet-transform based analysis technique capable of characterizing the scale- and directionality-resolved average intensity perturbations in static radiographs of the experiment. This technique uses the complete spatial information available in each radiograph to describe the structure evolution. We designed this analysis technique to generate a two-dimensional power spectrum for each radiograph from which we can recover information about structure widths, amplitudes, and orientations. The evolution of the distribution of power in the spectra for an experimental series is a potential metric for quantifying the structure size evolution as well as a system’s evolution towards isotropy.},
doi = {10.1063/1.4955097},
journal = {Review of Scientific Instruments},
number = 7,
volume = 87,
place = {United States},
year = 2016,
month = 7
}
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