17 March 2005 Planar velocity and scalar concentration measurements in shock-accelerated unstable fluid interfaces
Author Affiliations +
Proceedings Volume 5580, 26th International Congress on High-Speed Photography and Photonics; (2005); doi: 10.1117/12.577110
Event: 26th International Congress on High-Speed Photography and Photonics, 2004, Alexandria, Virginia, United States
Abstract
We report applications of several high-speed photographic techniques to diagnose fluid instability and the onset of turbulence in an ongoing experimental study of the evolution of shock-accelerated, heavy-gas cylinders. Results are at Reynolds numbers well above that associated with the turbulent and mixing transitions. Recent developments in diagnostics enable high-resolution, planar (2D) measurements of velocity fields (using particle image velocimetry, or PIV) and scalar concentration (using planar laser-induced fluorescence, or PLIF). The purpose of this work is to understand the basic science of complex, shock-driven flows and to provide high-quality data for code validation and development. The combination of these high-speed optical methods, PIV and PLIF, is setting a new standard in validating large codes for fluid simulations. The PIV velocity measurements provide quantitative evidence of transition to turbulence. In the PIV technique, a frame transfer camera with a 1 ms separation is used to image flows illuminated by two 10 ns laser pulses. Individual particles in a seeded flow are tracked from frame to frame to produce a velocity field. Dynamic PLIF measurements of the concentration field are high-resolution, quantitative dynamic data that reveal finely detailed structure at several instances after shock passage. These structures include those associated with the incipient secondary instability and late-time transition. Multiple instances of the flow are captured using a single frame Apogee camera and laser pulses with 140 ?s spacing. We describe tradeoffs of diagnostic instrumentation to provide PLIF images.
© (2005) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Cherie Goodenough, Sanjay Kumar, Mark Marr-Lyon, Adam Boyts, Katherine Prestridge, Paul Rightley, Christopher Tomkins, Michael Cannon, James Kamm, William Rider, Cindy Zoldi-Sood, Greg Orlicz, Peter Vorobieff, "Planar velocity and scalar concentration measurements in shock-accelerated unstable fluid interfaces", Proc. SPIE 5580, 26th International Congress on High-Speed Photography and Photonics, (17 March 2005); doi: 10.1117/12.577110; https://doi.org/10.1117/12.577110
PROCEEDINGS
7 PAGES


SHARE
KEYWORDS
Fiber optic gyroscopes

Diagnostics

Cameras

Particles

Interfaces

Velocity measurements

Molecules

Back to Top