Combustion characteristics of a DI-HCCI gasoline engine running at different boost pressures

Fuel, Volume 96, June 2012, Pages 546–555
Combustion characteristics of a DI-HCCI gasoline engine running at different boost pressures
Mustafa Canakci
Department of Automotive Engineering, Kocaeli University, 41380 Izmit, Turkey
Alternative Fuels R&D Center, Kocaeli University, 41275 Izmit, Turkey
Abstract
Homogeneous charge compression ignition (HCCI) combustion mode has a number of advantages over conventional combustion forms used in internal combustion (IC) engines: spark ignition (SI) and compression ignition (CI). This combustion mode provides low oxides of nitrogen (NOx) emissions and high thermal efficiency. However, it can produce higher unburned hydrocarbon (UHC) and carbon monoxide (CO) emissions than those of conventional engines because of lower combustion temperatures.
In naturally aspirated HCCI engines, low engine output power limits its use in current engine technologies. Intake air pressure boosting is a common way to improve engine output power and is used extensively in high performance SI and CI engine applications. Here, the author describes a study of the effect of inlet air pressure on combustion characteristics and exhaust emissions of a direct injection homogeneous charge compression ignition (DI-HCCI) gasoline engine. A heavy-duty diesel engine was converted to a HCCI direct-injection gasoline engine. Experiments were conducted at three different inlet air pressures while operating the engine at the same equivalence ratio and intake air temperature as in normally aspirated HCCI engine condition at different engine speeds.
Full Text Source (Subscription or Fee): http://www.sciencedirect.com/science/article/pii/S0016236112000701