Abstract

A novel algorithm developed for supersonic gas jet profile retrieval from interferometric measurement is presented. The algorithm uses the Fourier transform method for the phase map restoration and method based on radial profile approximation by a set of hyper-Gaussian functions and their forward Abel transform for 3D gas density profile restoration. The numerical algorithm of the 3D gas density profile restoration based on expansion of the density radial distribution by a basis of hyper-Gaussian functions is compared with algorithms of the inverse Abel transform. Examining accuracy of the algorithms shows that the developed approach is more stable than the inverse Abel transform, and, in the case of axisymmetric objects like supersonic gas jets, it provides higher accuracy. The developed technique was applied for studying the density profile of the pulsed nitrogen supersonic jet produced using a de’Laval nozzle with an exit diameter of 1.5 mm. It is shown that the radial density distributions at distances of 10–700 μm behind the nozzle exit have a hyper-Gaussian-like form with sharp boundaries and a jet top of $\sim 0.8\mathrm{mm}$ length, where gas density is about $5.5·{10}^{18}{\mathrm{cm}}^{-3}$ and varies by no more than 10%.

© 2019 Optical Society of America

Short-pulse laser interferometric measurement of absolute gas densities from a cooled gas jet

T. Ditmire and R. A. Smith
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Interferometric tomography for flow visualization of density fields in supersonic jets and convective flow

C. Söller, R. Wenskus, P. Middendorf, G. E. A. Meier, and F. Obermeier
Appl. Opt. 33(14) 2921-2932 (1994)

High-density gas capillary nozzles manufactured by hybrid 3D laser machining technique from fused silica

Vidmantas Tomkus, Valdas Girdauskas, Juozas Dudutis, Paulius Gečys, Valdemar Stankevič, and Gediminas Račiukaitis
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Tomographic imaging of nonsymmetric multicomponent tailored supersonic flows from structured gas nozzles

G. Golovin, S. Banerjee, J. Zhang, S. Chen, C. Liu, B. Zhao, J. Mills, K. Brown, C. Petersen, and D. Umstadter
Appl. Opt. 54(11) 3491-3497 (2015)

Optical quality of supersonic jets of various gases

D. W. Bogdanoff and R. J. Insuik
Appl. Opt. 21(5) 893-903 (1982)