scholarly journals Introduction of ME-GI - Gas Burning Low-Speed Diesel Engine

2016 ◽  
Vol 51 (2) ◽  
pp. 153-158
Author(s):  
Takahira Tabuchi ◽  
Takashi Fuchikami ◽  
Kouichi Namba ◽  
Yutaro Wada ◽  
Yasuyuki Tsuji
Keyword(s):  
Diesel Engine ◽  
Low Speed

CHARACTERISATION OF PARTICLES EMITTED BY A 14 MW LOW-SPEED DIESEL ENGINE

2001 ◽  
Vol 32 ◽  
pp. 77-78
Author(s):  
J.J. RODRIGUEZ-MAROTO ◽  
D. SANZ-RIVERA ◽  
J.L. DORRONSORO ◽  
F.J. GOMEZ-MORENO ◽  
R. MUÑOZ-BUENO ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Low Speed

scholarly journals Effects of multiple injections on combustion and emissions in a heavy-duty diesel engine at high load and low speed

2020 ◽  
Vol 12 (12) ◽  
pp. 168781402098462
Author(s):  
Yingying Lu ◽  
Yize Liu
Keyword(s):  
Diesel Engine ◽  
Single Injection ◽  
High Load ◽  
Post Injection ◽  
Heavy Duty ◽  
Low Speed ◽  
Multiple Injections ◽  
Heavy Duty Diesel Engine ◽  
Main Injection ◽  
Heavy Duty Diesel

Advanced multiple injection strategies have been suggested for compression ignition engines in order to meet the increasingly stringent emission regulations. Experiments and simulations were used to study effects of the main-injection mode (times), the post-injection proportion, and timing on combustion and emissions in a heavy-duty diesel engine at high load and constant low speed. The results reveal the following. The NOx emissions of 1main+1post, 2main+1post, and 3main+1post injections are all lower than those of single injection; the higher the number of main-injection pluses, the lower the NOx emissions. Enough main-post injection interval is needed to ensure post and main injections are relatively independent to entrain more fresh air to decrease the soot. Over-retarded post-injection timing tends to increase the soot due to the lower in-cylinder temperature. The combined effects of formation and oxidation determine the final soot. To gain the best trade-off of NOx and soot, compared with single injection, for the three multiple injections, the lowest soot emissions are gained at post-injection proportions of 15% and post-injection timings of 25°, 30°, and 35° CA ATDC, with soot reductions of 26.7%, −34.5%, and −112.8%, and NOx reductions of 5.88%, 21.2%, and 40.3%, respectively, for 1main+1post, 2main+1post, and 3main+1post injections.

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.

scholarly journals NOx Reduction of Marine Low Speed Diesel Engine with Low Pressure EGR

2017 ◽  
Vol 52 (4) ◽  
pp. 506-509
Author(s):  
Naohiro Hiraoka ◽  
Kazuhisa Ito ◽  
Takashi Ueda
Keyword(s):  
Diesel Engine ◽  
Nox Reduction ◽  
Low Pressure ◽  
Low Speed

Analyzing the Shear Heating Effects in Modeling the Hydrodynamic Lubrication of High Torque Low Speed Diesel Engine by Considering Different Viscosity-Grade Lubricants

2018 ◽  
Author(s):  
Saqib Naseer ◽  
Syed Adnan Qasim ◽  
Raja Amer Azim ◽  
Kishwat Ijaz Malik
Keyword(s):  
Diesel Engine ◽  
Journal Bearing ◽  
High Viscosity ◽  
Physical Contact ◽  
Lubricating Oil ◽  
Low Speed ◽  
Heating Effects ◽  
Shear Heating ◽  
Viscosity Grade ◽  
High Torque

Journal bearings of high torque diesel engines are used to cater for high combustion loads which are applied intermittently. A lubrication layer is provided between journal (crankshaft) and bearing to avoid contact between them. The relative velocity between crankshaft and journal bearing results in viscous shear heating among the different layers of lubricating oil. The shear heating reduces the viscosity of the lubricant that ultimately reduces the load carrying ability of the journal bearing. It offers a physical contact and reduces the designed life of crankshaft. In this study the 2-D transient numerical lubrication model is developed by employing the Reynolds equation to calculate the pressure and film thickness profiles as a function of crankshaft speed. The shear heating effects are determined by coupling the energy equation with lubrication model. The finite difference method is used and an appropriate numerical scheme is employed to simulate the conduction and convection based thermal energy transfer in transient and steady state journal bearing lubrication model. The lateral displacement of crankshaft is incorporated in the thermal model to analyze the effect of secondary dynamics of crankshaft. The viscosity and temperature relationship are used to ascertain its variation with temperature. The characteristic of three different viscosity-grade lubricates are incorporated separately in the model to carry out the comprehensive comparative analysis. The results are simulated for particular application where low operating speed and length to width ratio of journal bearing is fixed and analyzed the results for complete 720 degrees of crankshaft in its two revolutions. The results show that the oil with high viscosity produces high hydrodynamic pressures as compared to the oil that have low viscosity. The viscous shearing temperature reduces the hydrodynamic pressures but still the high viscosity lubricating oil have enough pressures to uplift the shaft after incorporating the shear heating effects. This study determines the hydrodynamic pressure, and variation of density, viscosity and thermal-conductivity with temperature for three different lubricating oils. These analyses will facilities towards the selection of appropriate lubricant for high torque low speed diesel engine in order to enhance the life of crankshaft.

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