Interferometric Ice Particle Imaging in a Wind Tunnel

Abstract

We report interferometric ice particle imaging and sizing in an icing wind tunnel with wind speeds of 70 m/s. Single particle interferograms are first analysed, size measurements are performed, and examples of possible reconstructed shapes are deduced from the interferometric images. Particle sizing is also performed in the case of ice particles whose out-of-focus images overlap, with or without Moiré phenomena. Results show that the IPI technique can be carried out for irregular rough particles in a critical environment such as in an icing wind tunnel with high wind speeds.

3D-Tracking of Sand Particles in a Wave Flume Using Interferometric Imaging

“…As for ice crystals in icing wind tunnels [40], this work showed the possibility to characterize rough particles in complex flows and large instruments using IPI, i.e., sand particles in wave flumes in this study. Recent studies have shown that the analysis of the interferometric images of rough particles could be refined using phase retrieval algorithms [37][38][39].…”

Particle Shape Recognition with Interferometric Particle Imaging Using a Convolutional Neural Network in Polar Coordinates

“…Optical techniques based on the use of nanosecond pulsed lasers address this constraint and offer interesting possibilities. One attractive method is interferometric particle imaging (IPI), which is the object of this paper [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. In this technique, particles are illuminated with a laser, and a CCD sensor records the interferometric image scattered by the particle (in an out-of-focus plane).…”

“…It is an off-axis technique, and there is no reference beam incident on the sensor, contrarily to holography. First developed to characterize spherical droplets or bubbles [1][2][3][4][5][6][7][8][9][10][11][12][13][14], IPI was extended to the characterization of irregular rough particles [15][16][17][18][19][20][21]. In the case of droplets, two-wave interference fringes (parallel bright lines) are analyzed: the diameter of the droplet (or bubble) is proportional to the frequency of the fringes.…”