Browse Publications Technical Papers 2019-01-1142
2019-04-02

Optical Experiments on Strong Knocking Combustion in Rapid Compression Machines with Different Fuels 2019-01-1142

Nowadays the strong knocking combustion involving destructive pressure wave or shock wave has become the main bottleneck for highly boosted engines when pursuing high thermal efficiency. However, its fundamental mechanism is still not fully understood. In this study, synchronization measurements through simultaneous pressure acquisition and high-speed direct photography were performed to comparatively investigate the strong knocking combustion of iso-octane and propane in a rapid compression machine with flat piston design. The pressure characteristics and visualized images of autoignition and reaction wave propagation were compared, and the correlations between thermodynamic trajectories and mixture reactivity progress were analyzed. The results show that iso-octane behaves a greater propensity to strong knocking combustion than propane at similar target pressures. Visualized images show that strong knocking combustion results from secondary autoignition and subsequent supersonic reaction wave propagation. Further analysis on thermodynamic trajectories shows that the secondary autoignition may closely correlate with the negative temperature coefficient behavior controlled by low-temperature chemistry.

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

Bulk Cylinder Flowfield Effects on Mixing in DISI Engines

2005-01-0096

View Details

TECHNICAL PAPER

Flow and Temperature Distribution in an Experimental Engine: LES Studies and Thermographic Imaging

2010-01-2237

View Details

TECHNICAL PAPER

Experimental and Theoretical Analysis of Flame Development and Misfire Phenomena in a Spark-Ignition Engine

920415

View Details

X