Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

Ultrafast time-gated ballistic-photon imaging and shadowgraphy in optically dense rocket sprays

Not Accessible

Your library or personal account may give you access

Abstract

Time-gated ballistic-photon imaging is a form of shadowgraphy in which an ultrashort, optical-Kerr- effect (order 2ps) time gate is used to enhance the relative intensity of ballistic versus multiply scattered photons. In the current work, this technique is adapted for what is believed to be the first time for use in the moderately dense environment (optical density 1.5 to 2) of a high-speed 5 to 15mm diameter rocket spray to improve image contrast and observe liquid-breakup phenomena. Unlike coherence gating, which is another form of ballistic imaging, the time-gating approach allows sufficient signal levels from ballistic and near-ballistic photons to enable time-resolved single-shot imaging. Direct comparisons with non-time-gated shadowgraphy indicate that the two techniques are sensitive to different features of the flowfield, with regions composed of a dense field of droplets being highly attenuated in conventional shadowgrams but appearing transparent to ballistic photons. This enables significant image contrast enhancement (6.61) of liquid-core structures and facilitates improved understanding of the primary and secondary breakup processes in sprays of moderate optical density.

© 2008 Optical Society of America

Full Article  |  PDF Article
More Like This
Comparison of femtosecond shadowgraphy and optical Kerr gated ballistic imaging for measurements of spray structures

Mingxin Wang, Jinhai Si, Wenjiang Tan, Yipeng Zheng, and Yang Yang
Opt. Express 27(11) 16080-16087 (2019)

Ballistic imaging of diesel sprays using a picosecond laser: characterization and demonstration

Sean P. Duran, Jason M. Porter, and Terence E. Parker
Appl. Opt. 54(7) 1743-1750 (2015)

Ballistic imaging of the liquid core for a steady jet in crossflow

Mark A. Linne, Megan Paciaroni, James R. Gord, and Terrence R. Meyer
Appl. Opt. 44(31) 6627-6634 (2005)

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Figures (7)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved