HEDGE technology eliminates low-speed pre-ignition in highly boosted engines

June 30, 2010

(PhysOrg.com) -- Southwest Research Institute (SwRI) has successfully demonstrated that its HEDGE (High-Efficiency, Dilute Gasoline Engine) technology, using cooled exhaust gas recirculation (EGR) and advanced ignition systems, suppresses low-speed pre-ignition in turbocharged gasoline direct-injection engines. Low-speed pre-ignition (LSPI) causes heavy engine knock and can seriously damage engine parts or cause complete engine failure.

The presence of low-speed pre-ignition is considered a major impediment to automobile manufacturers' efforts to aggressively downsize engines to reduce .

"This is a substantial development because it has the potential to affect every original equipment manufacturer (OEM). We have demonstrated that our HEDGE technology, primarily the use of cooled EGR, successfully suppresses low-speed pre-ignition events and in a way that improves ," said Dr. Terry Alger, manager of the Advanced Combustion and Emissions Section in SwRI's Engine, Emissions and Vehicle Research Division. "This problem was important enough to the automotive industry that SwRI chose to fund the work internally through our internal research and development program," Alger added.

The causes of low-speed pre-ignition events are not completely understood. They are random, infrequent occurrences that happen at low speed and high torque, Alger said. Under these conditions, a pre-ignition event leads to very heavy knock, which can cause catastrophic damage in only a few engine cycles.

Cooled EGR and its supporting technologies for high efficiency are being investigated in SwRI's HEDGE II consortium. HEDGE II is in the second year of a cooperative research consortium aimed at developing a high-efficiency for both light-duty automotive, medium-duty and heavy-duty markets. This four-year program expands on earlier efforts to improve gasoline engine technology for future emissions and fuel economy requirements.

The first HEDGE consortium focused on high levels of EGR combined with supporting technologies such as advanced ignition systems and advanced boosting technology to develop strategies for high efficiency.

"What we were able to accomplish through the first HEDGE consortium showed we could significantly improve gasoline engine performance and efficiency," Alger said. "Not only were we able to decrease fuel consumption, but we were also able to lower emissions significantly." SwRI engineers have been working on low-speed pre-ignition suppression internally for the past year.

"It is another significant step forward in developing an aggressive knock mitigation strategy," Alger said. "Our internally funded work has also looked into the fuel's effect on pre-ignition as well as potential non-EGR hardware and control solutions, but our first goal was to show how our cooled EGR technology suppresses the phenomenon."

SwRI also is working on examining lubricant effects on LSPI and expects to begin a separate consortium on the topic to develop new lubricants and lubricant testing methods.

HEDGE II consortium members represent the transportation industry in Asia, Europe and the United States. They are from a broad industry cross section, including light, heavy-duty and off-road manufacturers, component suppliers and oil and fuel companies. There are 23 members of the consortium, including most major automotive manufacturers.

"We will continue to develop these concepts that were initiated in the first HEDGE program and further develop the supporting technologies to implement this strategy in modern engines," Alger said. "We are already seeing concepts developed in HEDGE I enter production."

Explore further: 'Smart' Engine Shows Promise for Leaner, Greener Vehicle

Related Stories

Pint-sized car engine promises high efficiency

October 25, 2006

MIT researchers are developing a half-sized gasoline engine that performs like its full-sized cousin but offers fuel efficiency approaching that of today's hybrid engine system--at a far lower cost. The key? Carefully controlled ...

Fuel-injection System That Delivers 64 Miles Per Gallon

March 10, 2010

(PhysOrg.com) -- The best hybrid cars of today can only deliver about 48 miles per gallon. By using this newly developed fuel injection system a test vehicle was measured at achieving 64 miles per gallon in highway driving. ...

Engineer works to clean and improve engine performance

September 17, 2008

The five engines in Song-Charng Kong's Iowa State University laboratory have come a long way since Karl Benz patented a two-stroke internal combustion engine in 1879. There are fuel injectors and turbochargers and electrical ...

Recommended for you

Enhancing solar power with diatoms

October 20, 2017

Diatoms, a kind of algae that reproduces prodigiously, have been called "the jewels of the sea" for their ability to manipulate light. Now, researchers hope to harness that property to boost solar technology.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.