Combustion Characteristics of the Mustard Methyl Esters

2012 ◽  
Vol 510-511 ◽  
pp. 406-412 ◽  
Author(s):  
M.G. Bannikov ◽  
I.P. Vasilev

Mustard Methyl Esters (further biodiesel) and regular diesel fuel were tested in direct injection diesel engine. Analysis of experimental data was supported by an analysis of fuel injection and combustion characteristics. Engine fuelled with biodiesel had increased brake specific fuel consumption, reduced nitrogen oxides emission and smoke opacity, moderate increase in carbon monoxide emission with essentially unchanged unburned hydrocarbons emission. Increase in fuel consumption was attributed to lesser heating value of biodiesel and partially to decreased fuel conversion efficiency. Analysis of combustion characteristics revealed earlier start of injection and shorter ignition delay period of biodiesel. Resulting decrease in maximum rate of heat release and cylinder pressure was the most probable reason for reduced emission of nitrogen oxides. Analysis of combustion characteristics also showed that cetane index determined by ASTM Method D976 is not a proper measure of ignition quality of biodiesel. Conclusion was made on applicability of mustard oil as a source for commercial production of biodiesel in Pakistan. Potentialities of on improving combustion and emissions characteristics of diesel engine by reformulating biodiesel were discussed.

Author(s):  
Jingeun Song ◽  
Mingi Choi ◽  
Daesik Kim ◽  
Sungwook Park

The performance of a methane direct injection engine was investigated under various fuel injection timings and injection pressures. A single-cylinder optical engine was used to acquire in-cylinder pressure data and flame images. An outward-opening injector was installed at the center of the cylinder head. Experimental results showed that the combustion characteristics were strongly influenced by the end of injection (EOI) timing rather than the start of injection (SOI) timing. Late injection enhanced the combustion speed because the short duration between the end of injection and the spark-induced strong turbulence. The flame propagation speeds under various injection timings were directly compared using crank-angle-resolved sequential flame images. The injection pressure was not an important factor in the combustion; the three injection pressure cases of 0.5, 0.8, and 1.1 MPa yielded similar combustion trends. In the cases of late injection, the injection timings of which were near the intake valve closing (IVC) timing, the volumetric efficiency was higher (by 4%) than in the earlier injection cases. This result implies that the methane direct injection engine can achieve higher torque by means of the late injection strategy.


2013 ◽  
Vol 388 ◽  
pp. 217-222
Author(s):  
Mohamed Mustafa Ali ◽  
Sabir Mohamed Salih

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%.


Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4442
Author(s):  
Branko Lalić ◽  
Andrijana Poljak ◽  
Gojmir Radica ◽  
Antonija Mišura

Knowing the process of generating exhaust emissions and the determination of influential parameters are important factors in improving two-stroke slow-speed marine engines, particularly for further reductions in fuel consumption and stringent regulations on the limitation of nitrogen oxide emissions. In this article, a model of a marine low-speed two-stroke diesel engine has been developed. Experimental and numerical analyses of the nitrogen monoxide formations were carried out. When measuring the concentration of nitrogen oxides in the exhaust emissions, the amount of nitrogen dioxide (NO2) is usually measured, because nitrogen monoxide is very unstable, and due to the large amount of oxygen in the exhaust gases, it is rapidly converted into nitrogen dioxide and its amount is included in the total emission of nitrogen oxides. In this paper, the most significant parameters for the formation of nitrogen monoxide have been determined. Model validation was performed based on measured combustion pressures, engine power, and concentrations of nitrogen oxides at 50% and 75% of maximum continuous engine load. The possibilities of fuel consumption optimization and reduction in nitrogen monoxide emissions by correcting the injection timing and changing the compression ratio were examined. An engine model was developed, based on measured combustion pressures and scavenging air flow, to be used on board by marine engineers for rapid analyses and determining changes in the concentration of nitrogen oxides in exhaust emissions. The amount of nitrogen oxide in exhaust emissions is influenced by the relevant features described in this paper: fuel injection timing and engine compression ratio. The presented methodology provides a basis for further research about the simultaneous impact of changing the injection timing and compression ratio, exhaust valve opening and closing times, as well as the impact of multiple fuel injection to reduce consumption and maintain exhaust emissions within the permissible limits.


Author(s):  
S Rajkumar ◽  
Shamit Bakshi ◽  
Pramod S Mehta

Common rail direct injection (CRDI) system is a modern variant of direct injection diesel engine featuring higher fuel injection pressure and flexible injection scheduling which involves two or more pulses. Unlike a conventional diesel engine, the CRDI engine provides simultaneous reduction of oxides of nitrogen and smoke with an injection schedule that has optimized start of injection, fuel quantity in each injection pulse, and dwell periods between them. In this paper, the development of a multizone phenomenological model used for predicting combustion and emission characteristics of multiple injection in CRDI diesel engine is presented. The multizone spray configuration with their temperature and composition histories predicted on phenomenological spray growth and mixing considerations helps accurate prediction of engine combustion and emission (nitric oxide and soot) characteristics. The model predictions of combustion and emissions for multiple injection are validated with measured values over a wide range of speed and load conditions. The multizone and the two-zone model are compared and the reasons for better comparisons for the multizone model with experimental data are also explored.


Author(s):  
M. Nandeesh ◽  
R. Harishkumar ◽  
C.R. Rajashekar ◽  
N.R. Banapurmath ◽  
V.S. Yaliwal

The conventional diesel fuels are depleting at a faster pace. To reduce the burden on the economy, the reserves and sources for future has to be limited. The use of biodiesel derivatives from various sources and its blends in diesel engine has gained more importance in recent years. The present work investigates the feasibility of using dairy scum methyl esters (DSOME) of B20 blend in a modified single cylinder of common rail direct injection (CRDI) engine at a constant speed. Experiments were carried out at different injection timings from 25deg BTDC to 5deg ATDC with constant injection pressure as 600 bar. The fuel injection timing plays an important role in evaluating the performance, emission and combustion characteristics of the engine. The results show that the performance is improved with retarded injection timings compared to the operation of single cylinder DI engine fuelled with DSOME B20 biodiesel.


2008 ◽  
Vol 12 (1) ◽  
pp. 103-114 ◽  
Author(s):  
Dzevad Bibic ◽  
Ivan Filipovic ◽  
Ales Hribernik ◽  
Boran Pikula

An ignition delay is a very complex process which depends on a great number of parameters. In practice, definition of the ignition delay is based on the use of correlation expressions. However, the correlation expressions have very often limited application field. This paper presents a new correlation which has been developed during the research project on the direct injection M-type diesel engine using both the diesel and biodiesel fuel, as well as different values of a static injection timing. A dynamic start of injection, as well as the ignition delay, is defined in two ways. The first approach is based on measurement of a needle lift, while the second is based on measurement of a fuel pressure before the injector. The latter approach requires calculation of pressure signals delay through the fuel injection system and the variation of a static advance injection angle changing. The start of a combustion and the end of the ignition delay is defined on the basis of measurements of an in-cylinder pressure and its point of separation from a skip-fire pressure trace. The developed correlation gives better prediction of the ignition delay definition for the M-type direct injection diesel engine in the case of diesel and biodiesel fuel use when compared with the classic expression by the other authors available in the literature.


2005 ◽  
Vol 121 (2) ◽  
pp. 56-69
Author(s):  
Francisco TINAUT ◽  
Andrés MELGAR ◽  
Yolanda BRICEŃO ◽  
Alfonso HORRILLO

Alternative renewable fuels are more and more important due to increasing of oil prices, environmental concern (greenhouse and other pollutant gases) and, in some regions, their potential to help to conserve agricultural activity (previously aimed to food destination). For the case of vegetable oils several possibilities can be considered, such as mixtures of diesel fuel with both raw oil and oil-derived methyl-esters, where mixture proportions range between zero(pure diesel fuel) and 100% (pure alternative fuel). A third possibility is the use of mixtures of bio-ethanol (obtained om sugar or starch crops) and diesel fuel (e-diesel). Detailed results are presented relative to sunflower methyl-ester performance in engines (test bench), car vehicles (European test cycle) and endurance road tests for car vehicles and urban buses. These results show a favourable trend in the use of sunflower oil derived fuels in terms of emissions, with minor deterioration of power and fuel consumption. The trend is even more favourable if other aspects are considered such as positive energy balance of methyl-esters, relative simplicity of the transformation process, compatibility with the present diesel engine and car technology, possibility to deliver the alternative fuel through established automotive fuels distribution networks, etc. The main results of the presented tests can be summarised as follows: The mixtures of sunflower oil methyl diesel and diesel fuel, and especially those with less than 20% of ester, present perfectly valid properties and characteristics for their use in diesel engines without the need of modification. The current specification for Diesel fuel, EN 590, allows the presence of up to 5% of methyl ester, while, according to the authors results, this amount could be increased without consequences up to 20%. The results in engine test rigs confirm the general trends or other results. There is a reduction of full load power and torque, due to a lower heating value methyl esters, in accordance with an increase in fuel consumption (up to 16% for pure methyl ester). CO and HC are reduced for pure methyl ester and high contents of this, in spite of the fact that a moderate increase was observed for small contents of methyl ester at low engine rpm. NOx emissions show a very weak trend to increase as methyl ester content increases. The results obtained in two passenger cars running a European Driving Cycle presented the same trends. The endurance test covered 80,000 km in a passenger car with a fuel containing 10% of sunflower methyl ester. No problem was detected in lubricant, injection valve choking, fuel consumption and fuel filters. All the results were in accordance with it is expected for the same car running with pure diesel fuel.


Author(s):  
Jingeun Song ◽  
Mingi Choi ◽  
Daesik Kim ◽  
Sungwook Park

The performance of a methane direct injection engine was investigated under various fuel injection timings and injection pressures. A single-cylinder optical engine was used to acquire in-cylinder pressure data and flame images. An outward-opening injector was installed at the center of the cylinder head. Experimental results showed that the combustion characteristics were strongly influenced by the end of injection timing rather than the start of injection timing. Late injection enhanced the combustion speed because the short duration between the end of injection and the spark induced strong turbulence. The flame propagation speeds under various injection timings were directly compared using crank-angle-resolved sequential flame images. The injection pressure was not an important factor in the combustion; the three injection pressure cases of 0.5, 0.8, and 1.1 MPa yielded similar combustion trends. In the cases of late injection, the injection timings of which were near the Intake Valve Closing (IVC) timing, the volumetric efficiency was higher (by 4%) than in the earlier injection cases. This result implies that the methane direct injection engine can achieve higher torque by means of the late injection strategy.


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