Modeling Ignition and Combustion in Direct Injection Compression Ignition Engines Employing Very Early Injection Timing

Unlike homogeneous charge compression ignition (HCCI) that has the complexity in controlling the start of combustion event, partially premixed combustion (PPC) provides the flexibility of defining the ignition timing and combustion phasing with respect to the time of injection. In PPC, the stratification of the charge can be influenced by a variety of methods such as number of injections (single or multiple injections), injection pressure, injection timing (early to near TDC injection), intake boost pressure, or combination of several factors. The current study investigates the effect of these factors when testing two gasoline-like fuels of different reactivity (defined by Research Octane Number or RON) in a 1.9-L inline 4-cylinder diesel engine. From the collection of engine data, a full factorial analysis was created in order to identify the factors that most influence the outcomes such as the location of ignition, combustion phasing, combustion stability, and emissions. Furthermore, the interaction effect of combinations of two factors or more was discussed with the implication of fuel reactivity under current operating conditions. The analysis was done at both low (1000 RPM) and high speed (2000 RPM). It was found that the boost pressure and air/fuel ratio have strong impact on ignition and combustion phasing. Finally, injection-timing sweeps were conducted whereby the ignition (CA10) of the two fuels with significantly different reactivity were matched by controlling the boost pressure while maintaining a constant lambda (air/fuel equivalence ratio).

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Factors Affecting Performance of Dual Fuel Compression Ignition Engines

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.388.217 ◽

2013 ◽

Vol 388 ◽

pp. 217-222

Author(s):

Mohamed Mustafa Ali ◽

Sabir Mohamed Salih

Keyword(s):

Diesel Engine ◽

Fuel Consumption ◽

Thermal Efficiency ◽

Fuel Injection ◽

Direct Injection ◽

Injection System ◽

Dual Fuel ◽

Injection Timing ◽

Compression Ignition ◽

Factors Affecting

Compression Ignition Diesel Engine use Diesel as conventional fuel. This has proven to be the most economical source of prime mover in medium and heavy duty loads for both stationary and mobile applications. Performance enhancements have been implemented to optimize fuel consumption and increase thermal efficiency as well as lowering exhaust emissions on these engines. Recently dual fueling of Diesel engines has been found one of the means to achieve these goals. Different types of fuels are tried to displace some of the diesel fuel consumption. This study is made to identify the most favorable conditions for dual fuel mode of operation using Diesel as main fuel and Gasoline as a combustion improver. A single cylinder naturally aspirated air cooled 0.4 liter direct injection diesel engine is used. Diesel is injected by the normal fuel injection system, while Gasoline is carbureted with air using a simple single jet carburetor mounted at the air intake. The engine has been operated at constant speed of 3000 rpm and the load was varied. Different Gasoline to air mixture strengths investigated, and diesel injection timing is also varied. The optimum setting of the engine has been defined which increased the thermal efficiency, reduced the NOx % and HC%.

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Emission Pattern of Compression Ignition Engine Fueled with Blends of Tropical Almond Seed Oil-Based Biodiesel using Artificial Neural Network

Engineering and Technology Research Journal ◽

10.47545/etrj.2021.6.2.084 ◽

2021 ◽

Vol 6 (2) ◽

pp. 48-59

Author(s):

S.K. Fasogbon ◽

N.B. Jagunmolu ◽

A.O. Adeyera ◽

A.D. Ogunsola ◽

O.O. Laosebikan

Keyword(s):

Seed Oil ◽

Injection Timing ◽

Compression Ignition ◽

Emission Pattern ◽

Almond Oil ◽

Emission Profile ◽

Compression Ignition Engines ◽

Artificial Neural ◽

Engine Emission ◽

Ci Engines

Engine pollutants have been a significant source of concern in most countries around the world because they are one of the major contributors to air pollution, which causes cancer, lung disorders, and other severe illnesses. The need to reduce emissions and its consequences has prompted studies into the emission profile of internal combustion engines running on particular fuels. To this end, this study employed the power of Artificial Neural Networks (ANNs) to investigate the impact of injection timing on the emission profile of Compression Ignition Engines fuelled with blends of Tropical Almond Seed Oil based-biodiesel; by conducting a series of experimental tests on the engine rig and using the results to train the ANNs; to predict the emission profile to full scale. Blend percentages, load percentages, and injection timings were used as input variables, and engine emission parameters were used as output variables, to train the network. The results showed that injection timing affect emission output of CI engines fuelled with Tropical Almond Oil based biodiesel; and for the emission pattern to be friendly, injection timing must rather be retarded and not advanced. The results also showed that for different engine emission parameters, there is a strong association between the ANN output results and the actual experimental values; with mean relative error values less than 10%, which fall within the acceptable limits. For emission of CI engines fuelled with Tropical Almond Oil based biodiesel to be friendly in pattern, injection timing must be relatively retarded. The study also concluded that Artificial Neural Network (ANN) is a reliable tool for predicting Compression Ignition Engines emission profiles.

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Effect of hydrogen peroxide addition to methane fueled homogeneous charge compression ignition engines through numerical simulations

10.31224/osf.io/xywbc ◽

2017 ◽

Author(s):

Zachary M. Hammond ◽

John Hunter Mack ◽

Robert W. Dibble

Keyword(s):

Hydrogen Peroxide ◽

Homogeneous Charge Compression Ignition ◽

Injection Timing ◽

Compression Ignition ◽

Aqueous Hydrogen Peroxide ◽

Compression Ignition Engine ◽

Compression Ignition Engines ◽

Wide Range ◽

Phasing Control ◽

Homogeneous Charge

The effect of the direct injection of hydrogen peroxide into a port-injected methane fueled homogeneous charge compression ignition engine was investigated numerically. The injection of aqueous hydrogen peroxide was implemented as a means of combustion phasing control. A single cylinder homogeneous charge compression ignition engine (2.43 L Caterpillar) was modeled using the Cantera 2.0 flame code toolkit, the GRI-Mech 3.0 chemical reaction mechanism, and a single-zone slider-crank engine model. Start of injection timing and the amount of injected hydrogen peroxide were manipulated to achieve desired combustion phasing under a wide range of intake temperatures. As the concentration of hydrogen peroxide is increased, the combustion phasing is advanced up to 22 degrees for the conditions investigated in this study. This advancing effect is most pronounced at small concentrations (< 10 g H2O2 / kg CH4) and early injection timings (SOI < 25 degrees BTDC). The model suggests hydrogen peroxide can be introduced as a means of combustion phasing control while maintaining the low emissions and peak in-cylinder pressures inherent in homogeneous charge compression ignition engines.

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A Review of Early Injection Strategy in Premixed Combustion Engines

Applied Sciences ◽

10.3390/app9183737 ◽

2019 ◽

Vol 9 (18) ◽

pp. 3737 ◽

Cited By ~ 3

Author(s):

Xingyu Liang ◽

Zhiwei Zheng ◽

Hongsheng Zhang ◽

Yuesen Wang ◽

Hanzhengnan Yu

Keyword(s):

Diesel Engines ◽

Alternative Fuels ◽

Exhaust Emissions ◽

Injection Timing ◽

Compression Ignition ◽

Injection Strategy ◽

Advantages And Disadvantages ◽

Injection Parameters ◽

Performance And Emissions ◽

Early Injection

Due to the increasing awareness of environmental protection, limitations on exhaust emissions of diesel engines have become increasingly stringent. This challenges diesel engine manufacturers to find a new balance between engine performance and emissions. Advanced combustion modes for diesel engines, such as homogeneous charge compression ignition (HCCI) and premixed charge compression ignition (PCCI), which can simultaneously reduce exhaust emissions and substantially improve thermal efficiency, have drawn increasing attention. In order to allow enough time to prepare the homogeneous mixture, the early injection strategy has been utilized widely in HCCI and PCCI diesel engines. This paper is aimed at providing a comprehensive review of the effects of early injection parameters on the performance and emissions of HCCI and PCCI engines fueled by both diesel and alternative fuels. Various early injection parameters, including injection pressure, injection timing, and injection angle, are discussed. In addition, the effect of the blending ratio of alternative fuels is also summarized. Every change in parameters has its own advantages and disadvantages, which are explained in detail in order to help researchers choose the best early injection parameters for HCCI and PCCI engines.

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