2024-03-29T02:21:05Z
https://tsukuba.repo.nii.ac.jp/oai
oai:tsukuba.repo.nii.ac.jp:00028316
2022-04-27T08:54:57Z
2871:2874:1464
3:62:5598:1651
Initiation and sustaining mechanisms of stabilized Oblique Detonation Waves around projectiles
笠原, 次郎
Maeda, Shinichi
Sumiya, Satoshi
Kasahara, Jiro
Matsuo, Akiko
© 2012 The Combustion Institute. NOTICE: this is the author’s version of a work that was accepted for publication in Proceedings of the Combustion Institute. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Proceedings of the Combustion Institute, 34, 2, 2013, DOI:10.1016/j.proci.2012.05.035.
Direct initiations and stabilizations of three-dimensional conical detonation waves were attained by launching spheres with 1.06–1.31 times the C–J velocities into detonable mixtures. We conducted high time-resolution Schlieren visualizations of the whole processes over unsteady initiations to stable propagations of the stabilized Oblique Detonation Waves (ODWs) using a high-speed camera. The detonable mixtures were stoichiometric oxygen mixtures with acetylene, ethylene or hydrogen. They were diluted with argon in a 50% volumetric fraction, and a 75% diluted mixture was also tested for the acetylene/oxygen. The direct initiation of detonation by the projectile and the DDT process like the re-initiation appeared in the initiation process of stabilized ODW. This process eventually led to the stabilized ODW supported by the projectile velocity and the ringed shape detonation wave originating in the re-initiation. We modeled the spatial evolution of stabilized ODW after the re-initiation based on its C–J velocity and angle. The model qualitatively reproduced the measured development rate of stabilized ODW. We also discussed about the detonation stability for the curvature effect arising from the three-dimensional nature of stabilized ODW around the projectile. The curvature effect attenuated the detonation wave below its C–J velocity at the vicinity of projectile. The propagation limits of curvature effect will be responsible for the criticality to attain the stabilized ODWs. By accessing the detailed distributions of propagation velocities and curvature radiuses, the critical curvature radiuses normalized by the cell sizes experimentally revealed to be 8–10 or 15–18 for mixtures diluted with each 50% argon or 75% argon/krypton.
Elsevier Inc.
2013
eng
journal article
http://hdl.handle.net/2241/118456
https://tsukuba.repo.nii.ac.jp/records/28316
10.1016/j.proci.2012.05.035
1540-7489
AA11552208
Proceedings of the Combustion Institute
34
2
1973
1980
https://tsukuba.repo.nii.ac.jp/record/28316/files/PROC-CI_34-2-1973.pdf
application/pdf
571.9 kB
2013-12-25