Scientists reveal interaction between supersonic fuel spray and its shock wave

Mar 12, 2009
Scientists reveal interaction between supersonic fuel spray and its shock wave
Argonne physicist Jin Wang makes adjustments to a machine used for examining high speed jets at the Advanced Photon Source.

(PhysOrg.com) -- Shock waves are a well tested phenomenon on a large scale, but scientists at the Argonne National Laboratory and their collaborators from Wayne State University and Cornell University have made a breakthrough that reveals the interaction between shockwaves created by high-pressure supersonic fuel jets.

Shockwaves have been studied in the past by such methods as solid impacts and shock generators, but the high-pressure liquid created by micrometer sized nozzles can also reach supersonic speeds.

" occur in nature and have been studied for many years, but it has been difficult to examine the of shock waves created by high-pressure jets," Argonne scientist Jin Wang said. "High-intensity X-rays can penetrate the normally opaque jet stream allowing us to see the spray's internal structure and the gaseous environment around the jet, where the shock waves are generated.

Due to the supersonic spray's opaque nature, scientists have been unable to examine the internal structure of these jets and that has limited the improvement of high-pressure and high-speed jets and spray technologies, which are essential for numerous industrial and consumer applications, such as fuel combustions in engines, paint sprays, and industrial sprays. Using high-intensity X-rays created by the Advanced Photon Source and the Cornell High Energy Synchrotron Source at Cornell University, the scientists were able to examine the interaction between the shockwaves and liquid jets with a time resolution of one-millionth of a second. The scientists made the breakthrough by also developing a complex fluid dynamics simulation to understand the experimental observation of such a dynamical event.

In the case of fuel sprays for a , such a transient interaction can affect fuel breakup and thus efficiency and emissions. Researchers have quantitatively characterized the dynamic behaviors of the shock waves and shown that this combined experimental and computational approach can be applied to the fluid dynamics of many other systems including shock-wave-induced microbubble jetting, primary breakup modeling and cavitating flows.

The unique insights provided by the simulations were validated with time-resolved x-radiograph experiments. Because understanding the complex multiphase flow occurring in shock wave/fuel jet is extremely difficult, the agreement shown between the multiphase simulations and the experimental data provides an understanding of jet-gas interactions that has not been possible.

More information: A research article reporting this study can be seen in Physical Review Letters.

Source: Argonne National Laboratory

Explore further: Information storage for the next generation of plastic computers

add to favorites email to friend print save as pdf

Related Stories

Lancets Flights Probe Supersonic Shockwaves

Jan 22, 2009

(PhysOrg.com) -- NASA is concluding a series of flight tests to measure shock waves generated by an F-15 jet in an effort to validate computer models that could be used in designing quieter supersonic aircraft.

Researchers find new source of coherent light

Jan 13, 2006

With the exception of lasers and free-electron lasers, there hasn't been another fundamental way to produce coherent light for close to 50 years. However, a group of researchers from Lawrence Livermore National ...

Scientists Explain Mysterious Plasma Jets On The Sun

Jul 29, 2004

Scientists at the University of Sheffield and Lockheed Martin Solar and Astrophysics Lab have solved a 127-year-old problem about the origin of supersonic plasma jets (spicules) which continuously shoot up fro ...

Recommended for you

Could 'Jedi Putter' be the force golfers need?

1 hour ago

Putting is arguably the most important skill in golf; in fact, it's been described as a game within a game. Now a team of Rice engineering students has devised a training putter that offers golfers audio, ...

Better thermal-imaging lens from waste sulfur

16 hours ago

Sulfur left over from refining fossil fuels can be transformed into cheap, lightweight, plastic lenses for infrared devices, including night-vision goggles, a University of Arizona-led international team ...

User comments : 0

More news stories

Could 'Jedi Putter' be the force golfers need?

Putting is arguably the most important skill in golf; in fact, it's been described as a game within a game. Now a team of Rice engineering students has devised a training putter that offers golfers audio, ...

Under some LED bulbs whites aren't 'whiter than white'

For years, companies have been adding whiteners to laundry detergent, paints, plastics, paper and fabrics to make whites look "whiter than white," but now, with a switch away from incandescent and fluorescent lighting, different ...