Effect of Multiple Injection on the Performance and Emission Characteristics of Lean Burn Gasoline Direct Injection Engines

In-cylinder water injection is a promising approach for reducing NOx and soot emissions from internal combustion engines. It allows one to use a higher compression ratio by reducing engine knock; hence, higher fuel economy and power output can be achieved. However, water injection can also affect engine combustion and emission characteristics if water injection and injector parameters are not properly set. Majority of the previous studies on the water injection are done through experiments. Therefore, subtle aspects of water injection such as in-cylinder interaction of water sprays, spatial distribution of water vapor, and effect on flame propagation are not clearly understood and rarely reported in literature due to experimental limitations. Thus, in the present article, a computational fluid dynamics investigation is carried out to analyze the effects of direct water injection under various injector configurations on water evaporation, combustion, performance, and emission characteristics of a gasoline direct injection engine. The emphasis is given to analyze in-cylinder water spray interactions, flame propagation, water spray droplet size distribution, and water vapor spatial distribution inside the engine cylinder. For the study, the water-to-fuel ratio is varied from 0 to 1. Various water injector configurations using nozzle hole diameters of 0.14, 0.179, and 0.205 mm, along with nozzle holes of 4, 5, 6, and 7, are considered for comparison in addition to the case of no_water. Computational fluid dynamics models used in this study are validated with the available data in literature. From the results, it is found that the emission and performance characteristics of the engine are highly dependent on water evaporation characteristics. Also, the water-to-fuel ratio of 0.6 with 6 number of nozzle holes and the nozzle diameter of 0.14 mm results in the highest indicated mean effective pressure and the lowest NOx, soot, and CO emissions compared to other cases considered.

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Investigation of Flash Boiling Injection Schemes in Lean-burn Gasoline Direct Injection Engines

Applications in Energy and Combustion Science ◽

10.1016/j.jaecs.2021.100035 ◽

2021 ◽

pp. 100035

Author(s):

Zhe Sun ◽

Hongyu Wang ◽

Mingli Cui ◽

Mohamed Nour ◽

Xuesong Li ◽

...

Keyword(s):

Direct Injection ◽

Gasoline Direct Injection ◽

Lean Burn ◽

Direct Injection Engines ◽

Flash Boiling

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Performance and emission characteristics of a supercharged direct injection diesel engine using Rice Bran Oil

i-manager’s Journal on Future Engineering and Technology ◽

10.26634/jfet.4.4.173 ◽

2009 ◽

Vol 4 (4) ◽

pp. 48-53 ◽

Cited By ~ 1

Author(s):

Syed Altaf Hussain ◽

◽

G.Venkata Subbaiah ◽

V. Pandurangadu ◽

◽

...

Keyword(s):

Diesel Engine ◽

Rice Bran ◽

Rice Bran Oil ◽

Direct Injection ◽

Emission Characteristics ◽

Performance And Emission ◽

Direct Injection Diesel Engine

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Investigation of Cycle-to-Cycle Variations of In-Cylinder Processes in Gasoline Direct Injection Engines Operating With Variable Tumble Systems

10.4271/2004-01-0044 ◽

2004 ◽

Cited By ~ 14

Author(s):

J. Fischer ◽

A. Velji ◽

U. Spicher

Keyword(s):

Direct Injection ◽

Gasoline Direct Injection ◽

Direct Injection Engines

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Engine Analysis of Single Cylinder DI Diesel Engine Fuelled With Sunflower Oil, Sunflower Oil Methyl Ester and Its Blends

ASME 2006 Internal Combustion Engine Division Fall Technical Conference (ICEF2006) ◽

10.1115/icef2006-1573 ◽

2006 ◽

Cited By ~ 1

Author(s):

V. Anandram ◽

S. Ramakrishnan ◽

J. Karthick ◽

S. Saravanan ◽

G. LakshmiNarayanaRao

Keyword(s):

Diesel Engine ◽

Methyl Ester ◽

Sunflower Oil ◽

Direct Injection ◽

Emission Characteristics ◽

Single Cylinder ◽

Performance And Emission ◽

Di Diesel Engine ◽

Engine Emission ◽

Oil Sunflower

In the present work, the combustion, performance and emission characteristics of sunflower oil, sunflower methyl ester and its blends were studied and compared with diesel by employing them as fuel in a single cylinder, direct injection, 4.4 KW, air cooled diesel engine. Emission measurements were carried out using five-gas exhaust gas analyzer and smoke meter. The performance characteristics of Sunflower oil, Sunflower methyl ester and its blends were comparable with those of diesel. The components of exhaust such as HC, CO, NOx and soot concentration of the fuels were measured and presented as a function of load and it was observed that the blends had similar performance and emission characteristics as those of diesel. NOx emissions of sunflower oil methyl ester were slightly higher than that of diesel but that of sunflower oil was slightly lower than that of diesel. With respect to the combustion characteristics it was found that the biofuels have lower ignition delay than diesel. The heat release rate was very high for diesel than for the biofuel.

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Fuel Pressure Increase up to 50 MPa for Gasoline Direct-injection Engines

MTZ worldwide ◽

10.1007/s38313-018-0044-2 ◽

2018 ◽

Vol 79 (7-8) ◽

pp. 50-55 ◽

Cited By ~ 2

Author(s):

Felix Eitel ◽

Jörg Schäfer ◽

Achim Königstein ◽

Christof Heeger

Keyword(s):

Direct Injection ◽

Gasoline Direct Injection ◽

Pressure Increase ◽

Direct Injection Engines

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Simulation of Coarse Droplet and Liquid Column Formed around Nozzle Outlets Due to Valve Wobble of a Gasoline Direct Injection Injector

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4039808 ◽

2018 ◽

Vol 140 (10) ◽

Author(s):

Eiji Ishii ◽

Yoshihito Yasukawa ◽

Kazuki Yoshimura ◽

Kiyotaka Ogura

Keyword(s):

Surface Tension ◽

Particulate Matter ◽

Direct Injection ◽

Gasoline Direct Injection ◽

Fuel Spray ◽

Direct Injection Engines ◽

Fuel Injectors ◽

Multiple Injections ◽

Fuel Mixtures ◽

Opening And Closing

The generation of particulate matter (PM) is one problem with gasoline direct-injection engines. PM is generated in high-density regions of fuel. Uniform air/fuel mixtures and short fuel-spray durations with multiple injections are effective in enabling the valves of fuel injectors not to wobble and dribble. We previously studied what effects the opening and closing of valves had on fuel spray behavior and found that valve motions in the opening and closing directions affected spray behavior and generated coarse droplets during the end-of-injection. We focused on the effects of valve wobbling on fuel spray behavior in this study, especially on the behavior during the end-of-injection. The effects of wobbling on fuel spray with full valve strokes were first studied, and we found that simulated spray behaviors agreed well with the measured ones. We also studied the effects on fuel dribble during end-of-injection. When a valve wobbled from left to right, the fuel dribble decreased in comparison with a case without wobbling. When a valve wobbled from the front to the rear, however, fuel dribble increased. Surface tension significantly affected fuel dribble, especially in forming low-speed liquid columns and coarse droplets. Fuel dribble was simulated while changing the wetting angle on walls from 60 to 5 deg. We found that the appearance of coarse droplets in sprays decreased during the end-of-injection by changing the wetting angles from 60 to 5 deg.

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