This content is not included in your SAE MOBILUS subscription, or you are not logged in.
A Study of Newly Developed HCCI Engine With Wide Operating Range Equipped With Blowdown Supercharging System
ISSN: 1946-3936, e-ISSN: 1946-3944
Published August 30, 2011 by SAE International in United States
Citation: Kuboyama, T., Moriyoshi, Y., Hatamura, K., Takanashi, J. et al., "A Study of Newly Developed HCCI Engine With Wide Operating Range Equipped With Blowdown Supercharging System," SAE Int. J. Engines 5(2):51-66, 2012, https://doi.org/10.4271/2011-01-1766.
To extend the operating range of a gasoline HCCI engine, the blowdown supercharging (BDSC) system and the EGR guide were developed and experimentally examined. The concepts of these techniques are to obtain a large amount of dilution gas and to generate a strong in-cylinder thermal stratification without an external supercharger for extending the upper load limit of HCCI operation whilst keeping dP/dθmax and NOx emissions low. Also, to attain stable HCCI operation using the BDSC system with wide operating conditions, the valve actuation strategy in which the amount of dilution gas is smaller at lower load and larger at higher load was proposed. Additionally to achieve multi-cylinder HCCI operation with wide operating range, the secondary air injection system was developed to reduce cylinder-to-cylinder variation in ignition timing. As a result, the acceptable HCCI operation could be achieved with wide operating range, from IMEP of 135 kPa to 580 kPa. Compared to conventional SI operation, BSFC was improved by 14% ~ 35% with more than 99% reduction in NOx emissions.