Parametric study of pilot–main injection strategies on the performance of a light-duty diesel engine fueled with diesel or a WCO biodiesel–diesel blend

Some previous research results have shown that EGR (exhaust gas recirculation) rate, pilot fuel quantity, and main injection timing closely associated with engine emissions and fuel consumption. In order to understand the combined effect of EGR rate, pilot fuel quantity, and main injection timing on theNOx(oxides of nitrogen), soot, and ISFC (indicated specific fuel consumption), in this study, CFD (computational fluid dynamics) simulation together with the Taguchi method and the ANOVA (analysis of variance) technique was applied as an effective research tool. At first, simulation model on combustion and emissions of a light duty diesel engine at original baseline condition was developed and the model was validated by test. At last, a confirmation experiment with the best combination of factors and levels was implemented. The study results indicated that EGR is the most influencing factor onNOx. In case of soot emission and ISFC, the greatest influence parameter is main injection timing. For all objectives, pilot fuel quantity is an insignificant factor. Furthermore, the engine with optimized combination reduces by at least 70% forNOx, 20% in soot formation, and 1% for ISFC, in contrast to original baseline engine.

Download Full-text

Double Injection Strategies for Ethanol-Fuelled Gasoline Compression Ignition (GCI) Combustion in a Single-Cylinder Light-Duty Diesel Engine

10.4271/2016-01-2303 ◽

2016 ◽

Cited By ~ 6

Author(s):

Changhwan Woo ◽

Harsh Goyal ◽

Sanghoon Kook ◽

Evatt R. Hawkes ◽

Qing Nian Chan

Keyword(s):

Diesel Engine ◽

Compression Ignition ◽

Single Cylinder ◽

Double Injection ◽

Light Duty ◽

Injection Strategies

Download Full-text

Swirl ratio and post injection strategies to improve late cycle diffusion combustion in a light-duty diesel engine

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2017.05.101 ◽

2017 ◽

Vol 123 ◽

pp. 365-376 ◽

Cited By ~ 17

Author(s):

Jesús Benajes ◽

Jaime Martín ◽

Antonio García ◽

David Villalta ◽

Alok Warey

Keyword(s):

Diesel Engine ◽

Diffusion Combustion ◽

Post Injection ◽

Swirl Ratio ◽

Light Duty ◽

Injection Strategies

Download Full-text

Assessment on the consequences of injection strategies on combustion process and particle size distributions in Euro VI medium-duty diesel engine

International Journal of Engine Research ◽

10.1177/1468087419865652 ◽

2019 ◽

Vol 21 (4) ◽

pp. 683-697 ◽

Cited By ~ 2

Author(s):

Vicente Bermúdez ◽

Antonio García ◽

David Villalta ◽

Lian Soto

Keyword(s):

Particle Size ◽

Diesel Engine ◽

Size Distribution ◽

Particle Concentration ◽

Combustion Process ◽

Injection Pressure ◽

Injection Timing ◽

Injection Parameters ◽

Main Injection ◽

Injection Strategies

Although there are already several works where the influence of injection parameters on exhaust emissions, and specifically on particulate matter emissions, in diesel engines has been evaluated, the diversity in the results that can be found in the literature indicates the need to carry out new experiments that can provide more information about the influence of these parameters on modern diesel engines. This study intends to be placed within this scientific framework, hence a parametric study was carried out based on the independent modification of the main injection timing and the injection pressure with respect to the nominal conditions of a new Euro VI direct injection diesel engine. Four steady-state operation points of the engine map were chosen: 25% load and 950 r/min, 50% load and 1500 r/min, 75% load and 2000 r/min and 100% load and 2200 r/min, where in each of these operation points, the variations of the injection parameters in the study on the combustion process and its consequent impact on the particle size distribution, including an analysis of the geometric mean diameter values, were evaluated. The results showed that the different injection strategies adopted, despite not significantly affecting the engine efficiency, did cause a significant impact on particle number emissions. At the low load operation, the size distribution showed a bimodal structure, and as the main injection timing was delayed and the injection pressure was decreased, the nucleation-mode particle concentration decreased, while the accumulation-mode particle concentration increased. In addition, at medium load, the nucleation-mode particle emission decreased considerably while the accumulation-mode particle emission increased, and this increase was much greater with the main injection timing delay and the injection pressure reduction. Similar behavior was observed at high load, but with a much more prominent pattern.

Download Full-text

Effects of Different Injection Strategies on Combustion and Emission Characteristics of Diesel Engine Fueled with Dual Fuel

Processes ◽

10.3390/pr9081300 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1300

Author(s):

Jianbin Luo ◽

Zhonghang Liu ◽

Jie Wang ◽

Heyang Chen ◽

Zhiqing Zhang ◽

...

Keyword(s):

Diesel Engine ◽

Natural Gas ◽

Nox Emission ◽

Dual Fuel ◽

Emission Characteristics ◽

Post Injection ◽

Mixing Ratio ◽

Gas Mixing ◽

Main Injection ◽

Injection Strategies

In this work, an effective numerical simulation method was developed and used to analyze the effects of natural gas mixing ratio and pilot-main injection, main-post injection, and pilot-main-post injection strategies on the combustion and emission characteristics of diesel engine fueled with dual fuel. Firstly, the one-dimensional calculation model and three-dimensional CFD model of the engine were established by AVL-BOOST and AVL-Fire, respectively. In addition, the simplified chemical kinetics mechanism was adopted, which could accurately calculate the combustion and emission characteristics of the engine. The results show that the cylinder pressure and heat release rate decrease with the increase of the natural gas mixing ratio and the NOx emission is reduced. When the NG mixing ratio is 50%, the NOx and CO emission are reduced by 47% and 45%, respectively. When the SODI3 is 24 °CA ATDC, the NOx emission is reduced by 29.6%. In addition, with suitable pilot-main injection and pilot-main-post injection strategies, the combustion in the cylinder can be improved and the trade-off relationship between NOx and soot can be relaxed. Thus, the proper main-post injection strategy can improve the combustion and emission characteristics, especially the reduction in the NOx and CO emissions.

Download Full-text

Investigation Into Partially Premixed Combustion in a Light-Duty Diesel Engine Based on Different Injection Strategies

10.4271/2014-01-2681 ◽

2014 ◽

Cited By ~ 5

Author(s):

Zufeng Bao ◽

Xiaobei Cheng ◽

Liang Qiu ◽

Xingcun Luan

Keyword(s):

Diesel Engine ◽

Premixed Combustion ◽

Light Duty ◽

Partially Premixed Combustion ◽

Partially Premixed ◽

Injection Strategies

Download Full-text

Impact of counter-bore nozzle on the combustion process and exhaust emissions for light-duty diesel engine application

International Journal of Engine Research ◽

10.1177/1468087418819250 ◽

2018 ◽

Vol 20 (1) ◽

pp. 46-57 ◽

Cited By ~ 7

Author(s):

Raul Payri ◽

Joaquin De La Morena ◽

Javier Monsalve-Serrano ◽

Francesco Concetto Pesce ◽

Alberto Vassallo

Keyword(s):

Diesel Engine ◽

Combustion Process ◽

Exhaust Emissions ◽

Mixing Efficiency ◽

Rate Analysis ◽

Light Duty ◽

Brake Mean Effective Pressure ◽

Air Mixing ◽

Main Injection ◽

Spray Visualization

This article describes the main results of an investigation about counter-bore injector nozzle impact on the combustion process in a modern Euro 6 diesel engine. First, hydraulic and spray visualization tests have been performed, showing a potential advantage of such nozzle design in fuel–air mixing efficiency. Then, combustion performance has been assessed on a GM-designed 1.6-L four-cylinder engine. The engine has been installed on a dynamometric test bench and instrumented with an AVL cylinder pressure transducer for heat release rate analysis, as well as HORIBA MEXA gas analyzer for exhaust emissions and AVL 415 Smoke Meter. Engine efficiency and emissions have been analyzed on four different part-load steady-state points, representative of New European Driving Cycle and Worldwide harmonized Light duty Test Cycle certification cycles, and covering engine speeds from 1250 to 2000 r/min and brake mean effective pressure between 0.2 and 1.4 MPa. Results of indicated analysis show that counter-bore nozzles have significant differences in terms of pilot injection combustion at low load points, which in turn lead to a better ignition and shorter combustion of the main injection. In addition, an improvement of diffusive combustion is observed as load increases. Because of both, fuel consumption is reduced by approximately 1% with respect to a standard nozzle. Finally, an appreciable decrease in engine exhaust emissions has been recorded, especially in terms of particulate matter and hydrocarbon emissions. This reduction has been linked to the improvement of fuel–air mixing promoted by the counter-bore nozzle previously observed.

Download Full-text