Browse Publications Technical Papers 2006-01-0203
2006-04-03

Achievement of Medium Engine Speed and Load Premixed Diesel Combustion with Variable Valve Timing 2006-01-0203

A variable valve timing (VVT) mechanism was applied to achieve premixed diesel combustion at higher load for low emissions and high thermal efficiency in a light duty diesel engine. By means of late intake valve closing (LIVC), compressed gas temperatures near the top dead center are lowered, thereby preventing too early ignition and increasing ignition delay to enhance fuel-air mixing. The variability of effective compression ratio has significant potential for ignition timing control of conventional diesel fuel mixtures. At the same time, the expansion ratio is kept constant to ensure thermal efficiency. Combining the control of LIVC, EGR, supercharging systems and high-pressure fuel injection equipment can simultaneously reduce NOx and smoke. The NOx and smoke suppression mechanism in the premixed diesel combustion was analyzed using the 3D-CFD code combined with detailed chemistry. LIVC can achieve a significant NOx and smoke reduction due to lowering combustion temperatures (LTC: Low Temperature Combustion) and avoiding local over-rich regions in the mixtures, respectively.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

Full-Load HCCI Operation with Variable Valve Actuation System in a Heavy-Duty Diesel Engine

2007-01-0215

View Details

TECHNICAL PAPER

Effects of Injection Conditions on Mixture Formation Process in a Premixed Compression Ignition Engine

2000-01-1831

View Details

TECHNICAL PAPER

Dual Fuel Compression Ignition Combustion Concept for Gasoline and Diesel

2014-01-1319

View Details

X