Combined effects of combustion chamber geometry and injection strategy on combustion and emissions of a diesel engine

For a certain type of direct injection diesel engine, a three-dimensional model of a single-cylinder complete combustion chamber and in-take/exhaust port was established. Three-dimensional Computational Fluid Dynamics (CFD) analysis software CONVERGE was used for simulation. The effects of fuel injection strategy and combustion chamber geometry on combustion emissions of diesel engine were studied while the combustion chamber volume, engine compression ratio, total fuel injection quantity and total injection duration were kept unchanged. The results show that the strategy of multiple injection and reasonable shape of combustion chamber can effectively increase the turbulent kinetic energy in cylinder, improve the uniformity of oil-gas mixing, reduce the emission of pollutants, and increase the quality of after injection can further reduce the emissions of NOx and soot.

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Modelling of Spray–Swirl Interaction in Direct Injection Diesel Engine Combustion Chambers

Proceedings of the Institution of Mechanical Engineers Part D Transport Engineering ◽

10.1243/pime_proc_1985_199_156_01 ◽

1985 ◽

Vol 199 (3) ◽

pp. 187-198 ◽

Cited By ~ 5

Author(s):

P S Mehta ◽

A K Gupta

Keyword(s):

Diesel Engine ◽

Fuel Injection ◽

Direct Injection ◽

Three Dimensional ◽

Combustion Chambers ◽

Direct Injection Diesel Engine ◽

Wide Range ◽

Engine Combustion ◽

Computation Scheme ◽

Good Agreement

A mathematical model for predicting spray–swirl interaction in a direct injection diesel engine combustion chamber is developed using centre-line velocity vector/continuum approach. The model has three-dimensional features in fuel spray motion. The present model responds to the various air swirl, fuel injection and cylinder charge conditions. The predicted results are compared with the analytical and experimental data available from various sources in the two-dimensional case. Very good agreement is achieved over a wide range of data. The three-dimensional predictions are directly possible without any alteration in the computation scheme.

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RESEARCH ON THE PROCESS OF BIOFUEL INJECTION / BIODEGALŲ IŠPURŠKIMO PROCESO TYRIMAS

Mokslas - Lietuvos ateitis ◽

10.3846/mla.2012.61 ◽

2012 ◽

Vol 4 (4) ◽

pp. 381-385

Author(s):

Birutė Skukauskaitė ◽

Tomas Mickevičius

Keyword(s):

Diesel Engine ◽

Combustion Chamber ◽

Diesel Fuel ◽

Rapeseed Oil ◽

Fuel Injection ◽

Injection Pressure ◽

Fuel Spray ◽

Chamber Volume ◽

Air Density ◽

Engine Combustion

The purpose of this research was to examine penetration peculiarities of rapeseed oil injected into the combustion chamber of a diesel engine. For conducting tests, a stand imitating conditions (air density) for the engine combustion chamber was designed. The analysis of pictures obtained using a fast recording camera determined fuel injection into the chamber volume and calculated the velocity of spray head. It was established that fuel spray of injected rapeseed oil proceeds deeper into the combustion chamber than that of mineral diesel fuel. The parameters of fuel spray are mainly influenced by injection pressure rather than by the density of compressed gases. Santrauka Šio darbo tikslas buvo ištirti į dyzelinio variklio degimo kamerą įpurškiamos rapsų aliejaus čiurkšlės kitimo ypatumus, lyginant su mineraliniu dyzelinu. Tyrimams sukonstruotas stendas, kuriame buvo imituojamos sąlygos (oro tankis), esančios variklio degimo kameroje. Analizuojant spartaus filmavimo vaizdo kamera gautus vaizdus, buvo išmatuotas degalų čiurkšlės įsiskverbimo į degimo kamerą dydis, apskaičiuotas čiurkšlės fronto judėjimo greitis. Nustatyta, kad įpurškiamo rapsų aliejaus čiurkšlė į degimo kamerą įsiskverbia giliau, negu mineralinio dyzelino čiurkšlė. Įpurškiamų degalų čiurkšlės parametrams didesnės įtakos turi įpurškimo slėgis nei aplinkos dujų tankis.

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Effect of Combustion Chamber Geometry on Emissions From a Single-Cylinder Diesel Engine

ASME 2005 Internal Combustion Engine Division Fall Technical Conference (ICEF2005) ◽

10.1115/icef2005-1275 ◽

2005 ◽

Author(s):

Boggavarapu V. V. S. U. Prasad ◽

R. V. Ravikrishna

Keyword(s):

Diesel Engine ◽

Combustion Chamber ◽

Direct Injection ◽

Three Dimensional ◽

Cfd Simulations ◽

Government Regulations ◽

Single Cylinder ◽

Piston Bowl ◽

Computational Fluid Dynamics Cfd ◽

Valve Part

Many of the stationary power generation and agricultural pumping applications in India utilize diesel engines. Recently, as per Government regulations, these engines are required to satisfy stringent emissions norms. This forms the motivation for the present study on a stationary, direct-injection, single cylinder, 10 HP diesel engine. The selected engine was not satisfying the norms. The engine has a hemi- spherical piston bowl and an injector with a finite sac volume. The combustion chamber was made re-entrant and the injector was replaced with a sac-less injector. After these modifications, there is a significant change in emission levels. To understand clearly the effect of the combustion chamber geometry on the emission levels, three-dimensional computational fluid dynamics (CFD) simulations have been performed for the complete suction and closed-valve part of the cycle. Comparisons of turbulent kinetic energy and swirl levels of old and new geometries were systematically conducted. In contrary to the expected, that the swirl and turbulence levels are consistently less in the modified geometry than that of original geometry. A third combustion chamber was proposed and tested computationally. It was found that the in the proposed combustion chamber swirl and turbulence levels are much higher than the baseline engine. Thus, the proposed combustion chamber geometry shows significant potential for the engine to meet the prescribed norms.

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Numerical Simulation on Effect of Nozzle-Hole Layout on Spray Characteristics and Combustion in a DI Diesel Engine

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.476-478.448 ◽

2012 ◽

Vol 476-478 ◽

pp. 448-452

Author(s):

Jun Zhang ◽

Chang Pu Zhao ◽

Nai Zhuan Chen ◽

Da Lu Dong ◽

Bo Zhong

Keyword(s):

Numerical Simulation ◽

Diesel Engine ◽

Direct Injection ◽

Combustion Process ◽

Three Dimensional ◽

Three Dimensional Model ◽

Spray Characteristics ◽

Fuel Atomization ◽

Di Diesel Engine ◽

Nozzle Hole

Diesel spray characteristics are closely related to the combustion of the engine where the spray tip penetration and the fuel atomization play a key role especially for direct injection (DI) diesel engine. With different nozzles, the fuel atomization and evaporation will be different thereby affecting the combustion and emission characteristics. A three-dimensional model is built based on the parameters of a DI diesel engine, and its validation is also validated. Three nozzle-hole layouts are designed in this research, including the conventional hole, multi-hole, and group-hole. The spray characteristics and combustion process are studied with three different nozzle-hole layouts by the way of numerical simulation. Further more, the effect of inter-hole spacing of group-hole nozzle on the evaporation rate and combustion process is researched here.

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Development of the Long-Stroke Version of the Mitsubishi SU Diesel Engine

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2906628 ◽

1992 ◽

Vol 114 (3) ◽

pp. 590-596

Author(s):

Y. Nakamura ◽

M. Ito ◽

H. Arakawa

Keyword(s):

Diesel Engine ◽

Fuel Injection ◽

Stress Measurement ◽

Three Dimensional ◽

Injection System ◽

Dimensional Model ◽

Three Dimensional Model ◽

Regular Production ◽

Reduction Of Nox ◽

Long Stroke

A Mitsubishi S6U2 six-cylinder, in line diesel engine has been developed as a long-stroke version of the SU engine with a bore of 240 mm. This SU engine has a production record of more than 300 units. The stroke of this long-stroke version is 300 mm, compared with 260 mm for present SU engines. This paper introduces the S6U2 engine, which has now been put into regular production and describes research that has been conducted through the period of development. In the aspect of performance in particular, this paper explains reduction in fuel consumption by optimizing inlet and exhaust valve timings and improving turbocharger performance, and the reduction of NOx by modifying the fuel injection system. In the aspect of reliability, this paper explains FEM calculation with a three-dimensional model and a stress measurement under real operation for the crankshaft. The results of stress measurement on the crankcase are also described.

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Development of Novel Direct-injection Diesel Engine Combustion Chamber Designs Using Computational Fluid Dynamics

10.4271/971594 ◽

1997 ◽

Cited By ~ 9

Author(s):

P. K. Senecal ◽

A. Uludogan ◽

Rolf D. Reitz

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Diesel Engine ◽

Combustion Chamber ◽

Direct Injection ◽

Direct Injection Diesel Engine ◽

Engine Combustion

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Investigations of fuel injection strategy for cold starting direct-injection diesel engines

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

10.1243/09544070jauto473 ◽

2007 ◽

Vol 221 (11) ◽

pp. 1415-1424 ◽

Cited By ~ 14

Author(s):

N Brown ◽

V Gupta ◽

A La Rocca ◽

P J Shayler ◽

M Murphy ◽

...

Keyword(s):

Diesel Engines ◽

Fuel Injection ◽

Direct Injection ◽

Injection Strategy ◽

Cold Starting

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The Influence of Needle Eccentric Motion On Hole-to-Hole Injection Characteristics of a Two-Layered 8-Hole Diesel Injector

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4051413 ◽

2021 ◽

Author(s):

Tianyu Jin ◽

Yu Sun ◽

Chuqiao Wang ◽

Adams Moro ◽

Xiwen Wu ◽

...

Keyword(s):

Fuel Injection ◽

Lateral Displacement ◽

Three Dimensional ◽

Injection Rate ◽

Hole Injection ◽

Three Dimensional Model ◽

Maximum Displacement ◽

Fuel Flow ◽

Diesel Injection ◽

Eccentric Motion

Abstract The stringent emission regulations diesel engines are required to meet has resulted in the usage of multi-hole and ultra-multi-hole injectors, nowadays. In this research study, a double layered 8-hole diesel injection nozzle was investigated both numerically and experimentally. A three-dimensional model of the nozzle which was validated with experimental results was used to analyze the injection characteristics of each hole. The validation was conducted by comparing experiment and simulation injection rate results, acquired simultaneously from all the holes of the injector and the model. The fuel flow rates of the lower layered holes are higher than those of the upper layered holes. Two different needle eccentricity models were established. The first model only included the lateral displacement of the needle during needle lift. The needle reached maximum displacement at full needle lift. The second model considered the needle inelastic deformation into consideration. The needle radially displaces and glides along with the needle seat surface during needle lift. When the eccentricity reached maximum in the radial direction, the needle began to lift upwards vertically. The differences in injection characteristics under the different eccentricity models were apparent. The results indicated that the cycle injection quantity, fuel injection rate and cavitation of each hole were affected during the initial lifting stages of the needle lift. As the eccentricity of the needle increases, the injection rate uniformity from the nozzle hole deteriorates. The result showed that the upper layered holes were affected by the needle eccentricity during needle lift.

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