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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. Lastly, 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]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1291222
Alternate Identifier(s):
OSTI ID: 1260429
Report Number(s):
LA-UR-15-28836
Journal ID: ISSN 0034-6748
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Review of Scientific Instruments
Additional Journal Information:
Journal Volume: 87; Journal Issue: 7; Journal ID: ISSN 0034-6748
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 79 ASTRONOMY AND ASTROPHYSICS

Citation Formats

Merritt, Elizabeth Catherine, and Doss, Forrest William. Wavelet analysis methods for radiography of multidimensional growth of planar mixing layers. United States: N. p., 2016. Web. doi:10.1063/1.4955097.
Merritt, Elizabeth Catherine, & Doss, Forrest William. Wavelet analysis methods for radiography of multidimensional growth of planar mixing layers. United States. doi:10.1063/1.4955097.
Merritt, Elizabeth Catherine, and Doss, Forrest William. Wed . "Wavelet analysis methods for radiography of multidimensional growth of planar mixing layers". United States. doi:10.1063/1.4955097. https://www.osti.gov/servlets/purl/1291222.
@article{osti_1291222,
title = {Wavelet analysis methods for radiography of multidimensional growth of planar mixing layers},
author = {Merritt, Elizabeth Catherine and Doss, Forrest William},
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. Lastly, 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 = {Wed Jul 06 00:00:00 EDT 2016},
month = {Wed Jul 06 00:00:00 EDT 2016}
}

Journal Article:
Free Publicly Available Full Text
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Citation Metrics:
Cited by: 2works
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  • 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 powermore » 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.« less
  • Cited by 2
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