Modeling of the Fuel Behavior in the Intake Manifold of a Port-Injected Spark-Ignition Engine

Abstract The conversion of existing diesel engines to spark ignition (SI) operation by adding a low-pressure injector in the intake manifold for fuel delivery and replacing the original high-pressure fuel injector with a spark plug to initiate and control the combustion process can reduce U.S. dependence on petroleum imports and increase natural gas (NG) applications in heavy-duty transportation sectors. Since the conventional diesel combustion chamber (i.e., flat-head-and-bowl-in-piston-chamber) creates high turbulence, the converted NG SI engine can operate leaner with stable and repeatable combustion process. However, existing literatures point to a long late-combustion duration and increased unburned hydrocarbon emissions in such retrofitted engines that maintained the original combustion chamber. Consequently, the main objective of this paper was to report recent findings of NG combustion characteristics inside a bowl-in-piston combustion chamber that will add to the general understanding of the phenomena. The new results indicated that the premixed NG burn inside the bowl-in-piston combustion chamber will separate into a bowl-burn and a squish-burn processes in terms of burning location and timing. The slow burning event in the squish region explains the low slope of the burn rate towards the end of combustion in existing studies (hence the longer late-combustion period). In addition, the less-favorable conditions for the combustion in the squish region explained the increased carbon monoxide and unburned hydrocarbon emissions.

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Effect of intake manifold water injection on a natural gas spark ignition engine: an experimental study

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/257/1/012029 ◽

2017 ◽

Vol 257 ◽

pp. 012029 ◽

Cited By ~ 1

Author(s):

H Arruga ◽

F Scholl ◽

M Kettner ◽

O I Amad ◽

M Klaissle ◽

...

Keyword(s):

Experimental Study ◽

Natural Gas ◽

Water Injection ◽

Spark Ignition ◽

Spark Ignition Engine ◽

Intake Manifold

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A Numerical Study of Fuel Evaporation and Transportation in the Intake Manifold of a Port-Injected Spark-Ignition Engine

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1243/pime_proc_1991_205_167_02 ◽

1991 ◽

Vol 205 (3) ◽

pp. 161-175 ◽

Cited By ~ 27

Author(s):

C N Brown ◽

N Ladommatos

Keyword(s):

Numerical Study ◽

Spark Ignition ◽

Spark Ignition Engine ◽

Intake Manifold ◽

Fuel Evaporation

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A Numerical Simulation of Analysis of Backfiring Phenomena in a Hydrogen-Fueled Spark Ignition Engine

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4033182 ◽

2016 ◽

Vol 138 (10) ◽

Cited By ~ 4

Author(s):

K. A. Subramanian ◽

B. L. Salvi

Keyword(s):

Greenhouse Gas Emission ◽

Hot Spot ◽

Spark Ignition ◽

Spark Ignition Engine ◽

Intake Manifold ◽

Injection Timing ◽

Si Engine ◽

Engine Operation ◽

Study Results ◽

Residual Gas

Hydrogen utilization in spark ignition (SI) engines could reduce urban pollution including particulate matter as well as greenhouse gas emission. However, backfiring, which is an undesirable combustion process of intake charge in hydrogen-fueled SI engine with manifold-based injection, is one of the major technical issues in view of safety of engine operation. Backfiring occurs generally during suction stroke as the hydrogen–air charge interacts with residual gas, resulting in flame growth and propagation toward upstream of engine's intake manifold, resulting in stalling of engine operation and high risk of safety. This work is aimed at analysis of backfiring in a hydrogen-fueled SI engine. The results indicate that backfiring is mainly function of residual gas temperature, start of hydrogen injection timing, and equivalence ratio. Any hot-spot present in the cylinder would act as ignition source resulting in more chances of backfiring. In addition to this, computational fluid dynamics (CFD) analysis was carried out in order to assess flow characteristics of hydrogen and air during suction stroke in intake manifold. Furthermore, numerical analysis of intake charge velocity, flame speed (deflagration), and flame propagation (backfiring) toward upstream of intake manifold was also carried out. Some notable points of backfiring control strategy including exhaust gas recirculation (EGR) and retarded (late) hydrogen injection timing are emerged from this study for minimizing chance of backfiring. This study results are useful for development of dedicated SI engine for hydrogen fuel in the aspects of elimination of backfiring.

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Effect of Water Vapor Injection on the Performance and Emissions Characteristics of a Spark-Ignition Engine

Sustainability ◽

10.3390/su13169229 ◽

2021 ◽

Vol 13 (16) ◽

pp. 9229

Author(s):

Ming-Hsien Hsueh ◽

Chao-Jung Lai ◽

Meng-Chang Hsieh ◽

Shi-Hao Wang ◽

Chia-Hsin Hsieh ◽

...

Keyword(s):

Air Pollution ◽

Water Vapor ◽

Internal Combustion Engines ◽

Spark Ignition ◽

Spark Ignition Engine ◽

Injection System ◽

Intake Manifold ◽

Exhaust Emission ◽

Engine Torque ◽

Vapor Injection

The exhaust emissions from Internal Combustion Engines (ICE) are currently one of the main sources of air pollution. This research presented a method for improving the exhaust gases and the performance of a Spark-Ignition (SI) engine using a water vapor injection system and a Non-Thermal Plasma (NTP) system. These two systems were installed on the intake manifold to investigate their effects on the engine’s performance and the characteristics of exhaust emission using different air/fuel (A/F) ratios and engine speeds. The temperatures of the injected water were adjusted to 5 and 25 °C, using a thermoelectric cooler (TEC) temperature control device. The total hydrocarbons (HC), nitrogen oxide (NOx), and engine torque were measured at different A/F ratios and engine speeds. The results indicated that the adaptation of the water vapor injection system and NTP system increased the content of the combustibles and combustion-supporting substances while achieving better emissions and torque. According to the test results, while the engine torque under 25 °C water+NTP was raised to 7.29%, the HC under 25 °C water+NTP and the NOx under 25 °C water were reduced to 16.31% and 11.88%, respectively. In conclusion, the water vapor injection and the NTP systems installed on the intake manifold could significantly reduce air pollution and improve engine performance for a more sustainable environment.

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