skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Combustion, Control, and Fuel Effects in a Spark Assisted HCCI Engine Equipped with Variable Valve Timing

Abstract

Widespread implementation of homogeneous charge compression ignition (HCCI) engines is presently hindered by stability, control, and load range issues. Although the operable HCCI speed/load range is expanding, it is likely that the initial HCCI engines will rely on conventional combustion for part of the operating cycle. In the present study, we have investigated the role of fuel properties and chemistry on the operation of a spark-assisted gasoline HCCI engine. The engine employed is a single cylinder, 500 cc, port fuel injected research engine, operating near lambda = 1.0 and equipped with hydraulic variable valve actuation. HCCI is initiated by early exhaust valve closing to retain exhaust in the cylinder, thereby increasing the cylinder gas temperature. This is also referred to as a 'negative overlap' strategy. A total of 10 custom blended gasolines and three different batches of indolene from two suppliers were run at 5 speed-load combinations and performance was characterized by timing sweeps. Within the quality of the data set, we can say the all fuels provided equivalent combustion and performance characteristics when compared at the same combustion phasing. The fuels did, however, require different degrees of retained exhaust as measured by exhaust valve closing angle to achieve themore » same combustion phasing. Fuels with higher octane sensitivity were found to ignite more easily or more quickly and to burn more quickly than fuels with lower octane sensitivity. This is an expected result since the engine is naturally aspirated and operates with high compression temperatures due to the high retained exhaust fraction and recompression.« less

Authors:
 [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
1036163
DOE Contract Number:  
DE-AC05-00OR22725
Resource Type:
Conference
Resource Relation:
Conference: 2006 SAE International Congress and Exposition, Detroit, MI, USA, 20060402, 20060406
Country of Publication:
United States
Language:
English
Subject:
02 PETROLEUM; CHEMISTRY; COMBUSTION; COMPRESSION; ENGINES; GASOLINE; HYDRAULICS; IGNITION; IMPLEMENTATION; OCTANE; PERFORMANCE; SENSITIVITY; STABILITY; VALVES; 2006-01-0872

Citation Formats

Bunting, Bruce G. Combustion, Control, and Fuel Effects in a Spark Assisted HCCI Engine Equipped with Variable Valve Timing. United States: N. p., 2006. Web.
Bunting, Bruce G. Combustion, Control, and Fuel Effects in a Spark Assisted HCCI Engine Equipped with Variable Valve Timing. United States.
Bunting, Bruce G. Sun . "Combustion, Control, and Fuel Effects in a Spark Assisted HCCI Engine Equipped with Variable Valve Timing". United States. doi:.
@article{osti_1036163,
title = {Combustion, Control, and Fuel Effects in a Spark Assisted HCCI Engine Equipped with Variable Valve Timing},
author = {Bunting, Bruce G},
abstractNote = {Widespread implementation of homogeneous charge compression ignition (HCCI) engines is presently hindered by stability, control, and load range issues. Although the operable HCCI speed/load range is expanding, it is likely that the initial HCCI engines will rely on conventional combustion for part of the operating cycle. In the present study, we have investigated the role of fuel properties and chemistry on the operation of a spark-assisted gasoline HCCI engine. The engine employed is a single cylinder, 500 cc, port fuel injected research engine, operating near lambda = 1.0 and equipped with hydraulic variable valve actuation. HCCI is initiated by early exhaust valve closing to retain exhaust in the cylinder, thereby increasing the cylinder gas temperature. This is also referred to as a 'negative overlap' strategy. A total of 10 custom blended gasolines and three different batches of indolene from two suppliers were run at 5 speed-load combinations and performance was characterized by timing sweeps. Within the quality of the data set, we can say the all fuels provided equivalent combustion and performance characteristics when compared at the same combustion phasing. The fuels did, however, require different degrees of retained exhaust as measured by exhaust valve closing angle to achieve the same combustion phasing. Fuels with higher octane sensitivity were found to ignite more easily or more quickly and to burn more quickly than fuels with lower octane sensitivity. This is an expected result since the engine is naturally aspirated and operates with high compression temperatures due to the high retained exhaust fraction and recompression.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share: