Advanced Corona Ignition System improves gasoline combustion process

September 26, 2011 // By Christoph Hammerschmidt
Automotive supplier Federal-Mogul Corporation has introduced an innovative ignition system that promises to significantly improve the overall efficiency of the combustion process in gasoline engines. Thus, the Advanced Corona Ignition System (ACIS) could help to burn up to 10 % less fuel than engines with standard spark ignition, the company says.

Corona ignition creates a significantly larger high-intensity plasma ignition source, spread throughout the combustion chamber, when compared to conventional spark ignition systems. The ACIS technology provides for more thorough combustion and enables advanced combustion strategies like lean burn, highly diluted mixtures and very high exhaust gas recirculation (EGR), further increasing fuel efficiency. The company's ACIS utilizes materials and design strategies to facilitate high-volume production implementation on current and new engine architectures.

ACIS uses a high-energy, high frequency electrical field to produce repeatable, controlled ionization, creating multiple streams of ions to ignite the fuel mixture throughout the combustion chamber, whereas conventional spark ignition creates only a small arc in the gap between the electrodes of a spark plug.

The new ignition technology also allows for optimized timing of the start of combustion versus conventional ignition systems. ACIS generates rapid ignition and quick burning, ensuring greater conversion of the fuel energy to mechanical energy with the added potential for simultaneous reduction in engine cooling requirements.

"We have already recorded fuel consumption improvements of up to 10 percent on a 1.6-liter turbocharged gasoline direct injection engine, and there is potential for further improvements," said Kristapher Mixell, Federal-Mogul's director, advanced corona ignition system development, Powertrain Energy. "The technology enables powertrain engineers to more efficiently develop combustion strategies, such as stratified charge, lean burn and high levels of EGR, to reduce fuel consumption exhaust emissions," Mixell added.

Federal-Mogul has optimized its ACIS for ease of implementation in high-volume applications for both current and future powertrain architectures by designing it to package within the space of a spark-ignition system. The "two-piece" igniter architecture allows engine manufacturers the ability to replace traditional coil and plug systems with no adverse impact on engine design or assembly.

Eliminating the spark plug and its arc, ACIS eliminates the source of electrode erosion—the main cause of wear in a conventional spark-ignition system. This prolongs ignition system durability and extends service intervals.