Team Receives DOE Award for Groundbreaking Diesel Fuel Spray Research
DOE Award winners, (L-R) Jin Wang, Chris Powell, Yong Yue, and Steve Ciatti, stand
in front of their fuel spray injection chamber. Using the synchrotron beam at
the APS, the team is able to probe the fuel spray and study the process of combustion.
A team of Argonne scientists (Jin Wang, Steve Ciatti, Chris Powell, and
Yong Yue) recently won the 2002 National Laboratory Combustion and Emissions Control
R&D Award for groundbreaking work in diesel fuel sprays. For the first time
ever, the team used x-rays to penetrate through gasoline and diesel sprays and
made detailed measurements of fuel injection systems for diesel engines. This
technology uncovered a previously unknown shockwave in diesel sprays, which may
eventually help manufacturers improve the combustion process and thus build cleaner,
more efficient injection systems.
The team uses x-rays from the Advanced Photon Source (APS) — an Argonne
facility dedicated to producing synchrotron x-rays for research — to study
the fuel injection system of an engine and to see how combustion works. Studying
the breakup of liquid and gas particles near the fuel-injector nozzle will help
to advance fuel-injection technology.
"It gives us the ability to track the fuel mass of a spray," says
Steve Ciatti. "It's unique. The standard is to use optical-based techniques
like lasers or photos, but with those techniques you can only see the external
Laser light near the nozzle causes large numbers of droplets in the high-pressure
fuel spray to scatter, limiting the quantitative evaluation of the spray. The
highly penetrative nature of the X-ray beam makes them ideal for studying extremely
dense droplets composed of materials with a low atomic number. The team can more
completely define the structure of the mass of fuel and track where it is at any
given time using the x-ray beam.
Steve notes the research they are doing at APS is critical because cleaning
up diesel engines is necessary to reduce air pollution from semi-trucks, trains,
and potentially diesel-hybrid automobiles. To understand diesel emissions, it
is key to understand diesel combustion, which is defined by the fuel spray.
The team also has found the presence of shockwaves in modern injection systems
and measured the air/fuel composition in the core of diesel sprays. This observation
has never been made before. Jin notes that because they are able to vary the conditions
of the spray, they are able to study the structure and the speed of the shockwaves.
This research can then be used by fuel injection manufacturers to help design
better, more efficient systems. In addition, the technique offers promise for
similar studies in dense plasma and other optically dense structures.
The team plans to continue their research, increasing the temperature and pressure
surrounding the fuel injector to create a more diesel-like atmosphere. These conditions
will allow them to observe fuel injectors and combustion under more realistic