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Published on: June 24, 2013
Spectrally resolved velocity exchange spectroscopy of two-phase flow
A A Khrapitchev1, S Han, S Stapf
1School of Chemical and Physical Sciences, Victoria University, P.O. Box 600, Wellington, New Zealand. alex.khrapitchev@vuw.ac.nz
Abstract:
The Velocity EXchange SpectroscopY (VEXSY) technique, which provides a means to correlate macroscopic molecular displacements measured during two intervals separated by a variable mixing period, has been applied for the first time to a system of two-phase flow. The chemical shift difference between water and methyl protons has been exploited to simultaneously determine the probability of displacements, or propagator, of both components in a water/silicone oil mixture flowing through a glass bead pack. The joint two-time probability densities as well as the conditional probabilities of velocities show a clearly distinct dispersion behaviour of both fluids which is a consequence of the different wetting properties of the fluids with respect to the glass surface of the bead pack.
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