Effects of Injection Timing on Air-Fuel Mixing in a Direct-Injection Spark-Ignition Engine

1997 ◽  
Author(s):  
Zhiyu Han ◽  
Rolf D. Reitz ◽  
Jialin Yang ◽  
Richard W. Anderson
Keyword(s):  
Direct Injection ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Injection Timing ◽  
Fuel Mixing ◽  
Direct Injection Spark Ignition

scholarly journals Effect of engine conditions and injection timing on piston-top fuel films for stratified direct-injection spark-ignition operation using E30

2019 ◽  
Vol 21 (2) ◽  
pp. 302-318 ◽  
Author(s):  
Carl-Philipp Ding ◽  
David Vuilleumier ◽  
Namho Kim ◽  
David L Reuss ◽  
Magnus Sjöberg ◽  
...  
Keyword(s):  
Refractive Index ◽  
Direct Injection ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Injection Timing ◽  
Fuel Film ◽  
Index Matching ◽  
Refractive Index Matching ◽  
Wall Wetting ◽  
Direct Injection Spark Ignition

Mid-level ethanol/gasoline blends can provide knock resistance benefits for stoichiometric spark-ignition engine operation, but previous studies have identified challenges associated with spray impingement and wall wetting, leading to excessive particulate matter emissions. At the same time, stratified-charge spark-ignition operation can provide increased thermal efficiency, but care has to be exercised to avoid excessive in-cylinder soot formation. In support of the use of mid-level ethanol/gasoline blends in advanced spark-ignition engines, this study presents spray and fuel-film measurements in a direct-injection spark-ignition engine operated with a 30 vol.%/70 vol.% ethanol/gasoline blend (E30). Crank-angle resolved fuel-film measurements at the piston surface are conducted using two different implementations of the refractive index matching technique. A small-angle refractive index matching implementation allows quantification of the wetted area, while a large-angle refractive index matching implementation enables semi-quantitative measurements of fuel-film thickness and volume, in addition to fuel-film area. The fuel-film measurements show that both the amount of fuel deposited on the piston and the shape of the fuel-film patterns are strongly influenced by the injection timing, duration, intake pressure, and coolant temperature. For combinations of high in-cylinder gas density and long injection duration, merging of the individual spray plumes, commonly referred to as spray collapse, can cause a dramatic change to the shape and thickness of the wall fuel films. Overall, the study provides guidance to engine designers aiming at minimizing wall wetting through tailored combinations of injection timings and durations.

Effect of injection timing on combustion and soot formation in a direct injection spark ignition engine fueled with butanol

2016 ◽  
Vol 18 (5-6) ◽  
pp. 490-504 ◽  
Author(s):  
Simona Silvia Merola ◽  
Adrian Irimescu ◽  
Luca Marchitto ◽  
Cinzia Tornatore ◽  
Gerardo Valentino
Keyword(s):  
Soot Formation ◽  
Direct Injection ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Injection Timing ◽  
Direct Injection Spark Ignition

Spray Development and Wall Impingement of Ethanol and Gasoline in an Optical Direct Injection Spark Ignition Engine

2015 ◽  
Author(s):  
Mohammad Fatouraie ◽  
Margaret S. Wooldridge ◽  
Benjamin R. Petersen ◽  
Steven T. Wooldridge
Keyword(s):  
Fuel Injection ◽  
Direct Injection ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Coolant Temperature ◽  
Absolute Pressure ◽  
Injection Timing ◽  
Cylinder Wall ◽  
Wall Impingement ◽  
Direct Injection Spark Ignition

The effects of ethanol on spray development and wall impingement of a direct injection spark ignition (DISI) engine was investigated using high-speed imaging of the fuel spray in an optically-accessible engine. Neat anhydrous ethanol (E100), reference grade gasoline (E0) and a 50% blend (by volume) of gasoline and ethanol (E50) were used in the study. The experiments were conducted using continuous firing conditions for an intake manifold absolute pressure of 57 kPA, and engine speed of 1500 RPM. Retarded fuel injection timing was used (with start of injection at 250 °bTDC) to isolate the effects of cylinder wall impingement, and lean fuel-to-air ratios (ϕ=0.8–0.9) were used to minimize sooting and coating of the transparent cylinder liner. The effects of three engine coolant temperatures (25, 60 and 90 °C) and two fuel rail pressures (100 and 150 bar) on the features of the spray and the spray interaction with the wall were studied for the different fuels. Quantitative metrics were defined to analyze the spatial features of the spray related to wall impingement. Gasoline (E0) sprays exhibited higher sensitivity to coolant temperature compared to ethanol (E100) in terms of the shape of the spray and wall impingement. Higher fuel injection pressure increased the spray tip penetration rate and fuel impingement with the wall for E0 and E100, despite creating wider plume angles of the fuel sprays.

Sign in / Sign up

Export Citation Format

Share Document