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| Experiment
Description |
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Richtmyer-Meshkov
instability occurs whenever a shock wave passes over a
nearly planar interface separating two fluids of unequal
density. It is one of the most fundamental fluid
instabilities and is of importance to applications
ranging from astrophysics to supersonic combustion.
Previous experimental studies have been hampered by the
difficulty in generating a well defined interface
between two gases. We have overcome this difficulty in
our experiments by utilizing a flow system in which a
light gas (Air) and a heavy gas (SF6) flow from opposite
ends of the driven section of a
vertical shock tube. The gases meet and are
allowed to exit the tube through slots in the shock tube
wall thus forming a stagnation point flow at the
interface location. A sinusoidal perturbation can then
be given to this interface by gently oscillating the
shock tube in the horizontal direction to produce
standing waves. A weak shock wave is then generated by
puncturing a diaphragm which travels down the tube where
it impacts the interface to produce the instability.
Planar Laser Induced Fluorescence (PLIF) is utilized to
visualize the flow in these experiments by seeding the
air with acetone vapor and illuminating it with a sheet
of laser light produced by a pulsed Nd:YAG laser. The
fluorescent images are then captured by a cooled CCD
camera. Pictures below shows a sequence of images
illustrating the evolution of the instability in these
experiments. The incident shock wave causes the
initially sinusoidal perturbation to grow and develop
into the characteristic mushroom structures. However the
interface is reaccelerated in the opposite direction by
an expansion wave which ultimately produces a much more
complex turbulent flow. |
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| Experiment
animation |
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File size: 585.64
KBytes
Estimated download time: 229.05 sec at 28.8 Kbps 116.55
sec at 56.6 Kbps
256 Color Palette |
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| Experiment
publications |
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Jones, M.A., and
Jacobs, J.W., "A Membraneless Experiment for the Study
of Richtmyer-Meshkov Instability,"
Phys. Fluids , 9, 3078-3085, 1997.
File size: 2539 kB |
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Jacobs, J.W. and Collins, B.D. (1999) "Experimental
study of the Richtmyer-Meshkov instability of a diffuse
interface," Proceedings of the 22rd International
Symposium on Shock Waves, London, England, July 1999.
File size: 290 kB |
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Page last updated:
01.01.2006 |
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