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Title: Velocity measurement by coherent x-ray heterodyning

Abstract

We present a small-angle coherent x-ray scattering technique used for measuring flow velocities in slow moving materials. The technique is an extension of X-ray Photon Correlation Spectroscopy (XPCS): It involves mixing the scattering from moving tracer particles with a static reference that heterodynes the signal. This acts to elongate temporal effects caused by flow in homodyne measurements, allowing for a more robust measurement of flow properties. Using coherent x-ray heterodyning, velocities ranging from 0.1 to 10 μm/s were measured for a viscous fluid pushed through a rectangular channel. We describe experimental protocols and theory for making these Poiseuille flow profile measurements and also develop the relevant theory for using heterodyne XPCS to measure velocities in uniform and Couette flows.

Authors:
ORCiD logo; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
USDOE
OSTI Identifier:
1342248
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 88; Journal Issue: 1
Country of Publication:
United States
Language:
ENGLISH
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY

Citation Formats

Lhermitte, Julien R. M., Rogers, Michael C., Manet, Sabine, and Sutton, Mark. Velocity measurement by coherent x-ray heterodyning. United States: N. p., 2017. Web. doi:10.1063/1.4974099.
Lhermitte, Julien R. M., Rogers, Michael C., Manet, Sabine, & Sutton, Mark. Velocity measurement by coherent x-ray heterodyning. United States. doi:10.1063/1.4974099.
Lhermitte, Julien R. M., Rogers, Michael C., Manet, Sabine, and Sutton, Mark. Sun . "Velocity measurement by coherent x-ray heterodyning". United States. doi:10.1063/1.4974099.
@article{osti_1342248,
title = {Velocity measurement by coherent x-ray heterodyning},
author = {Lhermitte, Julien R. M. and Rogers, Michael C. and Manet, Sabine and Sutton, Mark},
abstractNote = {We present a small-angle coherent x-ray scattering technique used for measuring flow velocities in slow moving materials. The technique is an extension of X-ray Photon Correlation Spectroscopy (XPCS): It involves mixing the scattering from moving tracer particles with a static reference that heterodynes the signal. This acts to elongate temporal effects caused by flow in homodyne measurements, allowing for a more robust measurement of flow properties. Using coherent x-ray heterodyning, velocities ranging from 0.1 to 10 μm/s were measured for a viscous fluid pushed through a rectangular channel. We describe experimental protocols and theory for making these Poiseuille flow profile measurements and also develop the relevant theory for using heterodyne XPCS to measure velocities in uniform and Couette flows.},
doi = {10.1063/1.4974099},
journal = {Review of Scientific Instruments},
number = 1,
volume = 88,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2017},
month = {Sun Jan 01 00:00:00 EST 2017}
}
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