scholarly journals Effect of Engine Speeds and Dimethyl Ether on Methyl Decanoate HCCI Combustion and Emission Characteristics Based on Low-Speed Two-Stroke Diesel Engine

2020 ◽  
Vol 27 (2) ◽  
pp. 85-95
Author(s):  
Shiye Wang ◽  
Li Yao
Keyword(s):  
Diesel Engine ◽  
Dimethyl Ether ◽  
Engine Speed ◽  
Emission Characteristics ◽  
Low Speed ◽  
Mixing Ratios ◽  
Hcci Combustion ◽  
Marine Diesel ◽  
Excess Air Coefficient ◽  
Methyl Decanoate

AbstractThe combustion and emission characteristics of homogeneous charge compression ignition (HCCI) fuelled by methyl decanoate (MD) with different engine speeds and dimethyl ether (DME) mixing ratios are investigated in this work. Engine data of a MAN B&W 6S70MC low-speed two-stroke marine diesel engine were used for the reactor. The results show that a decrease of engine speed has little effect on the in-cylinder temperature and pressure of the engine at constant excess air coefficient of 1.5. Meanwhile, NOx emissions decrease with a decrease of engine speed in pure MD HCCI combustion. The results also indicate that NOx and CO2 emissions decrease significantly with an increase in the percentage of DME in MD and DME mixing combustion at a constant total mole fraction and engine speed of 85 revolutions per minute (r/min).

scholarly journals EMISSION CHARACTERISTICS OF JATROPHA-ETHANOL AND JATROPHA- DIMETHYL ETHER FUEL BLENDS ON A DI DIESEL ENGINE

2013 ◽  
Vol 42 (1) ◽  
pp. 38-46 ◽  
Author(s):  
M. Loganathan ◽  
A. Anbarasu ◽  
A. Velmurugan
Keyword(s):  
Diesel Engine ◽  
Dimethyl Ether ◽  
Engine Speed ◽  
Engine Performance ◽  
Emission Characteristics ◽  
Brake Thermal Efficiency ◽  
Performance And Emission ◽  
Fuel Blends ◽  
Engine Combustion ◽  
Di Diesel Engine

In this study, Biodiesel -Dimethyl Ether (BDE) and Biodiesel Ethanol (BE) were tested in a 4-cylinderdirect-injection diesel engine to investigate the performance and emission characteristics of the engine underfive engine loads at the maximum torque. The engine speed was maintained at 1500 rpm. Here the jatropha oilis used as a non edible oil to produce the biodiesel. The ethanol and dimethyl ether is used as an additive toenhance the engine combustion. The BDE 5 (biodiesel 95% and dimethyl ether 5%) , BDE 10 (biodiesel 90%and dimethyl ether 10%) BDE 15(biodiesel 85% and dimethyl ether 15%) BE5 (biodiesel 95% and ethanol 5%),BE10 (biodiesel 90% and ethanol 10%) and BE15 (biodiesel 85% and ethanol 15%) were tested in the engine.The results indicate that when compared with neat jatropha, the engine performance increased and emissionlevel decreased with adding the ethanol and diethyl ether with methyl ester of jatropha oil. In comparison withneat jatropha, the BDE5 and BE15 blends have higher brake thermal efficiency (BTE) of 12% and 13%respectively. The experimental results showed that the CO, HC emission is decreased and NOx emission isincreased for higher blends of additives. The brakes specific fuel consumption (BSFC) decreased for BDE5 andBE5 compared to other combination of fuel.DOI: http://dx.doi.org/10.3329/jme.v42i1.15941 

scholarly journals Impact of Pilot Injection on Combustion and Emission Characteristics of a Low-Speed Two-Stroke Marine Diesel Engine

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 417
Author(s):  
Xingyu Liang ◽  
Ziyang Liu ◽  
Kun Wang ◽  
Xiaohui Wang ◽  
Zhijie Zhu ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Diesel Engines ◽  
Thermal Efficiency ◽  
Injection Timing ◽  
Emission Characteristics ◽  
Marine Diesel Engine ◽  
Pilot Injection ◽  
Long Distance ◽  
Low Speed ◽  
Marine Diesel

Low-speed two-stroke marine diesel engines dominate the modern global long-distance transportation market; with the increasingly stringent regulations, the combustion and emissions of these engines is gaining intense interest. The primary objective of the present study was to understand the effects of air-fuel mixing by pilot injection strategy on the combustion and emission characteristics of the marine diesel engines through a numerical study. Specifically, a computational fluid dynamic (CFD) model was established and validated by experimental data for a typical low-speed two-stroke marine diesel engine. The combustion parameters under different stages were analyzed, including mean in-cylinder temperature and pressure, indicated thermal efficiency (ITE), indicated specific fuel consumption (ISFC), and distribution of fuel-air mixture. Results indicated that, due to the premixing effect, the pilot injection produced unburned soot from the main injection’s ignition as well as decrease the intervals between the middle and final stages of combustion, thus raising the in-cylinder temperature. The interaction between the reduction of soot particles resulted from the increased temperature, and the decrease of the stage intervals led to lower overall boundary heat loss, which improved the effective thermal efficiency. The pilot injection timing and quality, respectively, showed quadratic and linear impact modes on engine performance and emissions.

Modeling and performance analysis of diesel engine considering the heating effect of blow-by on cylinder intake gas

2021 ◽  
pp. 146808742110692
Author(s):  
Zhenyu Shen ◽  
Yanjun Li ◽  
Nan Xu ◽  
Baozhi Sun ◽  
Yunpeng Fu ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Engine Performance ◽  
Marine Diesel Engine ◽  
Heating Effect ◽  
Shipping Industry ◽  
Low Speed ◽  
Proposed Model ◽  
International Regulations ◽  
Marine Diesel ◽  
And Performance

Recently, the stringent international regulations on ship energy efficiency and NOx emissions from ocean-going ships make energy conservation and emission reduction be the theme of the shipping industry. Due to its fuel economy and reliability, most large commercial vessels are propelled by a low-speed two-stroke marine diesel engine, which consumes most of the fuel in the ship. In the present work, a zero-dimensional model is developed, which considers the blow-by, exhaust gas bypass, gas exchange, turbocharger, and heat transfer. Meanwhile, the model is improved by considering the heating effect of the blow-by gas on the intake gas. The proposed model is applied to a MAN B&W low-speed two-stroke marine diesel engine and validated with the engine shop test data. The simulation results are in good agreement with the experimental results. The accuracy of the model is greatly improved after considering the heating effect of blow-by gas. The model accuracy of most parameters has been improved from within 5% to within 2%, by considering the heating effect of blow-by gas. Finally, the influence of blow-by area change on engine performance is analyzed with considering and without considering the heating effect of blow-by.

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