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Showing papers on "Diesel engine published in 2003"


Journal ArticleDOI
TL;DR: The main factors affecting transesterification are the molar ratio of glycerides to alcohol, catalyst, reaction temperature and pressure, reaction time and the contents of free fatty acids and water in oils as mentioned in this paper.

1,115 citations


Journal ArticleDOI
01 Jul 2003-Fuel
TL;DR: In this paper, the exhaust emissions of a Diesel direct injection Perkins engine fueled with waste olive oil methyl ester were studied at several steady-state operating conditions, characterized with neat biodiesel from used olive oil and conventional Diesel fuel.

669 citations


Journal ArticleDOI
TL;DR: The effective density provides the relationship between mobility and aerodynamic equivalent diameters and shows that mass distributions of diesel particles measured with the SMPS-APM are in good agreement with distributions measured with a MOUDI and a nano-MOUDI for particles larger than approximately 60 nm.
Abstract: We used the aerosol particle mass analyzer (APM) to measure the mass of mobility-classified diesel exhaust particles. This information enabled us to determine the effective density and fractal dimension of diesel particles as a function of engine load. We found that the effective density decreases as particle size increases. TEM images showed that this occurs because particles become more highly agglomerated as size increases. Effective density and fractal dimension increased somewhat as engine load decreased. TEM images suggest that this occurs because these particles contain more condensed fuel and/or lubricating oil. Also, we observed higher effective densities when high-sulfur EPA fuel (∼360 ppm S) was used than for Fischer−Tropsch fuel (∼0 ppm S). In addition, the effective density provides the relationship between mobility and aerodynamic equivalent diameters. The relationship between these diameters enables us to intercompare, in terms of a common measure of size, mass distributions measured with t...

502 citations


Journal ArticleDOI
TL;DR: In this paper, various methods of using vegetable oil (Jatropha oil) and methanol such as blending, transesterification and dual fuel operation were studied experimentally.
Abstract: In this work various methods of using vegetable oil (Jatropha oil) and methanol such as blending, transesterification and dual fuel operation were studied experimentally. A single cylinder direct injection diesel engine was used for this work. Tests were done at constant speed of 1500 rev min −1 at varying power outputs. In dual fuel operation the methanol to Jatropha oil ratio was maintained at 3:7 on the volume basis. This is close to the fraction of methanol used to prepare the ester with Jatropha oil. Brake thermal efficiency was better in the dual fuel operation and with the methyl ester of Jatropha oil as compared to the blend. It increased form 27.4% with neat Jatropha oil to a maximum of 29% with the methyl ester and 28.7% in the dual fuel operation. Smoke was reduced with all methods compared to neat vegetable oil operation. The values of smoke emission are 4.4 Bosch Smoke Units (BSU) with neat Jatropha oil, 4.1 BSU with the blend, 4 BSU with methyl ester of Jatropha oil and 3.5 BSU in the dual fuel operation. The Nitric Oxide (NO) level was lower with Jatropha oil compared to diesel. It was further reduced in dual fuel operation and the blend with methanol. Dual fuel operation showed higher hydrocarbon (HC) and carbon monoxide (CO) emissions than the ester and the blend. Ignition delay was higher with neat Jatropha oil. It increased further with the blend and in dual fuel operation. It was reduced with the ester. Peak pressure and rate of pressure rise were higher with all the methods compared to neat Jatropha oil operation. Jatropha oil and methyl ester showed higher diffusion combustion compared to standard diesel operation. However, dual fuel operation resulted in higher premixed combustion. On the whole it is concluded that transesterification of vegetable oils and methanol induction can significantly enhance the performance of a vegetable oil fuelled diesel engine.

443 citations


Journal ArticleDOI
TL;DR: In this article, fuel consumption and exhaust emissions measurements from a single cylinder, stationary diesel engine are described, and two types of biodiesel appeared to have equal performance, and irrespective of the raw material used for their production, their addition to the marine diesel fuel improved the particulate matter, unburned hydrocarbons, nitrogen oxide and carbon monoxide emissions.
Abstract: Vegetable oils are produced from numerous oil seed crops. While all vegetable oils have high-energy content, most require some processing to assure safe use in internal combustion engines. Some of these oils already have been evaluated as substitutes for diesel fuels. With the exception of rape seed oil which is the principal raw material for biodiesel fatty acid methyl esters, sunflower oil, corn oil and olive oil, which are abundant in Southern Europe, along with some wastes, such as used frying oils, appear to be attractive candidates for biodiesel production. In this paper, fuel consumption and exhaust emissions measurements from a single cylinder, stationary diesel engine are described. The engine was fueled with pure marine diesel fuel and blends containing two types of biodiesel, at proportions up to 50%. The two types of biodiesel appeared to have equal performance, and irrespective of the raw material used for their production, their addition to the marine diesel fuel improved the particulate matter, unburned hydrocarbons, nitrogen oxide and carbon monoxide emissions.

387 citations


Journal ArticleDOI
TL;DR: In this article, a thermal desorption particle beam mass spectrometer (TDPBMS) and tandem differential mobility analyzers (TDMA) were used for on-line measurements of the chemical composition and volatility of nanoparticles and larger particles emitted from a modern, heavy-duty diesel engine operated at light and medium loads under laboratory conditions.

363 citations


Journal ArticleDOI
TL;DR: In this paper, an additive used to keep the blends homogenous and stable, and an ignition improver, which can enhance cetane number of the blends, have favorable effects on the physicochemical properties related to ignition and combustion of diesel fuel with 10% and 30% ethanol by volume.

355 citations


Journal ArticleDOI
TL;DR: In this article, the effect of the biodiesel produced from high free fatty acid feedstocks on engine performance and emissions was investigated, and two different biodiesels were prepared from animal fat-based yellow grease with 9% free fatty acids and from soybean oil.
Abstract: Biodiesel is a non-toxic, biodegradable and renewable alternative fuel that can be used with little or no engine modifications. Biodiesel is currently expensive but would be more cost effective if it could be produced from low-cost oils (restaurant waste, frying oils, animal fats). These low-cost feedstocks are more challenging to process because they contain high levels of free fatty acids. A process for converting these feedstocks to fuel-grade biodiesel has been developed and described previously. The objective of this study was to investigate the effect of the biodiesel produced from high free fatty acid feedstocks on engine performance and emissions. Two different biodiesels were prepared from animal fat-based yellow grease with 9% free fatty acids and from soybean oil. The neat fuels and their 20% blends with No. 2 diesel fuel were studied at steady-state engine operating conditions in a four-cylinder turbocharged diesel engine. Although both biodiesel fuels provided significant reductions in particulates, carbon monoxide, and unburned hydrocarbons, the oxides of nitrogen increased by 11% and 13% for the yellow grease methyl ester and soybean oil methyl ester, respectively. The conversion of the biodiesel fuel's energy to work was equal to that from diesel fuel.

343 citations


Journal ArticleDOI
TL;DR: In this paper, a single cylinder water-cooled direct-injection diesel engine designed to develop a power output of 3.7 kW at 1500 rev/min was tested under variable load conditions, with different quantities of hydrogen being inducted.

303 citations


Proceedings ArticleDOI
TL;DR: In this paper, double injection technique was used by Common Rail injection system and the first injection was used as an early injection for fuel diffusion and to advance the changing of fuel to lower hydrocarbons.
Abstract: Ignition and combustion control of HCCI (Homogeneous Charge Compression Ignition) in DI (Direct Injection) Diesel Engine were examined. In this study, double injection technique was used by Common Rail injection system. The first injection was used as an early injection for fuel diffusion and to advance the changing of fuel to lower hydrocarbons (i.e. low temperature reaction). The second injection was used as an ignition trigger for all the fuel. It was found that the ignition of the premixed gas could be controlled by the second injection when the early injection was maintaining low temperature reaction. It was found that as the boost pressure increased, ignition timing advanced slightly and the rate of pressure increase markedly decreased. The rate of pressure increase is one of the factors concerning operation limit in this combustion. Therefore, the VNT (Variable Nozzle Turbo-charger) was applied to the production engine to allow boost pressure control. Spray characteristics and combustion analysis images were investigated by the shadowgraph method. Luminous flame was not observed. The fluctuation due to the low temperature reaction was observed from the shadowgraph images. Many ignition points appeared in the combustion chamber. Low NOx and smoke were possible both in the first injection and in the second injection by this combustion. This HCCI concept was named as UNIBUS (Uniform Bulky Combustion System) by the author et al. and applied to the production engine (1KD-FTV, 3 liter-4cylinder) in August 2000 in the Japanese market.

284 citations


Journal ArticleDOI
TL;DR: In this paper, an experimental investigation of the characteristics of dual fuel operation when liquid diesel is partially replaced with natural gas under ambient intake temperature in a direct injection (DI) diesel engine is presented.

Journal ArticleDOI
TL;DR: In this article, the authors describe the production of emulsions from biomass fast pyrolysis liquid and diesel fuel for utilisation in diesel engines and test the emulsion on different diesel engines.
Abstract: The current method of utilising biomass derived fast liquid (bio-crude oil or bio-oil) in a diesel engine requires three fuels and a complex start-up and shut down procedure. For more rapid and successful commercialisation of this renewable liquid fuel, a more convenient and cheaper method of utilisation is needed that provides a single fuel that is stable and readily ignites in a compression engine. This paper describes the production of emulsions from biomass fast pyrolysis liquid and diesel fuel for utilisation in diesel engines. The objective is to allow unmodified diesel engines to run on fast pyrolysis liquid derived from biomass without the cost and complexity of a dual fuel system. The immediate application is in stationary engines for power generation, but there are longer term opportunities for use as a transport fuel. This paper describes the production of the emulsions that have been tested in different diesel engines (tests in engines is reported in a separate paper).

Journal ArticleDOI
TL;DR: In this paper, a simple linear regression analysis was conducted to relate the emission rates of the metal contents in vehicle exhaust to the consumption rates of metal contents contained in diesel fuel, and the results indicated that the relatively high amount of metal content emitted from diesel engines strongly suggests that the measurement on the control of diesel fuel should be taken in the future.

Journal ArticleDOI
TL;DR: The objective of this study was to develop an improved analytical procedure to quantify 28 mononitro- and dinitro-PAHs, including numerous isomers, in air and diesel particulate SRMs, to provide isomer identification and reference concentrations for a large number of nitrated-polycyclic aromatic hydrocarbons.

Journal ArticleDOI
TL;DR: In this paper, an ignition delay correlation was developed based on engine data, which is suitable for predictions under both steady-state and transient conditions, using a modified Arrhenius expression to account for variations in fuel/air composition during transients.
Abstract: Available correlations for the ignition delay in pulsating, turbulent, two-phase, reacting mixtures found in a diesel engine often have limited predictive ability, especially under transient conditions. This study focuses on the development of an ignition delay correlation, based on engine data, which is suitable for predictions under both steady-state and transient conditions. Ignition delay measurements were taken on a heavy-duty diesel engine across the engine speed/load spectrum, under steady-state and transient operation. The dynamic start of injection was calculated by using a skip-fire technique to determine the dynamic needle lift pressure from a measured injection pressure profile. The dynamic start of combustion was determined from the second derivative of measured cylinder pressure. The inferred ignition delay measurements were correlated using a modified Arrhenius expression to account for variations in fuel/air composition during transients. The correlation has been compared against a number of available correlations under steady-state conditions. In addition, comparisons between measurements and predictions under transient conditions are made using the extended thermodynamic simulation framework of Assanis and Heywood. It is concluded that the proposed correlation provides better predictive capability under both steady-state and transient operation.

Journal ArticleDOI
TL;DR: In this article, a detailed analysis of the hydrocarbon adsorption-desorption and oxidation behavior of diesel particulate emitted by a modern diesel engine and collected on a SiC diesel filter is performed by use of thermogravimetric and differential scanning calorimetry analysis (TGA-DSC) non-isothermal tests were performed with samples collected directly from a ceramic filter connected to the exhaust system of the diesel engine running under low and medium speed and load operating conditions with and without fuel additive.

Journal ArticleDOI
TL;DR: In this paper, the authors present the results of experimental work carried out to evaluate the exhaust emissions characteristics of ordinary Malaysian coconut oil (COCO) blended with conventional diesel oil (OD) fueled in a diesel engine and found that the addition of 30% COCO with OD produced higher brake power and net heat release rate with a net reduction in exhaust emissions such as HC, NOx, CO, smoke and polycyclic aromatic hydrocarbon (PAH).

Proceedings ArticleDOI
TL;DR: In this article, the soot and soot-precursor formation characteristics of oxygenated fuels using experiments and numerical simulations under direct-injection diesel engine conditions were explored.
Abstract: This paper explores soot and soot-precursor formation characteristics of oxygenated fuels using experiments and numerical simulations under direct-injection diesel engine conditions. The paper strives to achieve four goals: 1)to introduce the "oxygen ratio" for accurate quantification of reactant-mixture stoichiometry for both oxygenated and non-oxygenated fuels; 2) to provide experimental results demonstrating that some oxygenates are more effective at reducing diesel soot than others; 3) to present results of numerical simulations showing that detailed chemical-kinetic models without complex fluid mechanics can capture some of the observed trends in the sooting tendencies of different oxygenated fuels; and 4) to provide further insight into the underlying mechanisms by which oxygenate structure and in-cylinder processes can affect soot formation in Dl diesel engines. The oxygenates that were studied are di-butyl maleate (DBM) and tri-propylene glycol methyl ether (TPGME). Experiments were conducted in a constant-volume combustion vessel and a single-cylinder Dl diesel engine, each with extensive optical access. Numerical simulations were conducted using detailed chemical-kinetic mechanisms for combustion of the oxygenated fuels in a homogeneous-reactor configuration. Both the experimental and the numerical approaches showed that fuels containing the TPGME oxygenate are more effective at reducing soot than those containing the DBM oxygenate. Detailed chemical-kinetic analysis showed that over 30% of the oxygen in DBM is unavailable for eliminating soot precursors. Fuel oxygenation and enhanced charge-gas entrainment are investigated as in-cylinder soot-reduction strategies. Fuel oxygenation to a given mixture stoichiometry with either TPGME or DBM is found to be more effective at reducing soot than enhancing the entrainment of oxygen from the charge gases. The two strategies can be used together to achieve non-sooting combustion. The results suggest that jet-wall and multiple-jet interactions in an engine could produce regions that are conducive to soot formation, providing an extra challenge for soot reduction as non-sooting conditions are approached.

Proceedings ArticleDOI
TL;DR: In this paper, a survey of recent studies and research on vegetable oil based fuels is given within the historical context, fuel related properties are reviewed and compared with conventional diesel fuel, performance and emission characteristics are highlighted and techniques to decrease viscosities are discussed.
Abstract: The present review aims to study the prospects and opportunities of introducing vegetable oils and their derivatives as fuels in diesel engines A survey of recent studies and research on vegetable oil based fuels is given within the historical context Fuel related properties are reviewed and compared with conventional diesel fuel The use of neat vegetable oil (edible and/or non-edible), biodiesel and its blends in a diesel engine has been discussed Performance and emission characteristics are highlighted Suitability of different combustion chambers for diesel engine operation with vegetable oils is outlined Techniques to decrease viscosities are discussed Current developments on the use of vegetable oils and its blends, biodiesel and its blends in diesel engines are examined

Journal ArticleDOI
TL;DR: In this article, the effects of various BCO/diesel emulsions on the injection systems of different diesel engines are investigated and compared, and the issue of erosion and/or corrosion of the injector nozzle is examined, and dedicated tests have been carried out.
Abstract: The use of biomass derived pyrolysis oils, bio crude oil (BCO), in diesel engine requires deep modifications to the engine, such as the adoption of dual fuel systems and pilot injection: BCO/diesel emulsions are expected to significantly reduce the need for these adaptations. This paper describe the effects of various BCO/diesel emulsions on the injection systems of different diesel engines. Materials used for injectors’ nozzles and needles are investigated and compared. The issue of the erosion and/or corrosion of the injector nozzle is examined, and dedicated tests have been carried out. The experimental results suggested that corrosion accelerated by the high velocity turbulent flow in the spray channels is the dominant factor. A stainless steel nozzle has been built and successfully tested. Long term validation is however still needed.

Proceedings ArticleDOI
TL;DR: In this paper, a nonlinear control concept for the coordinated control of the exhaust gas recirculation (EGR) valve and the variable geometry turbocharger (VGT) in a common-rail diesel engine is presented.
Abstract: In this article model-based controller design techniques are investigated for the transient operation of a common-rail diesel engine in order to optimize driveability and to reduce soot emissions. The computer-aided design has benefits in reducing controller calibration time. This paper presents a nonlinear control concept for the coordinated control of the exhaust gas recirculation (EGR) valve and the variable geometry turbocharger (VGT) in a common-rail diesel engine. The overall controller structure is set up to regulate the total cylinder air-charge with a desired fresh air-charge amount by means of controlling the intake manifold pressure and estimating the fresh air-charge inducted into the cylinders. During varying engine operating conditions the two control loops are coordinated by a compensation of the EGR valve action through the VGT controller. A nonlinear exhaust pressure controller is designed to regulate the estimated turbocharger power which compensates all EGR valve actions and results in the desired turbocharger power management. The VGT and EGR controllers, the cylinder air-charge observer and the turbocharger identification algorithm are developed based on a nonlinear diesel engine model. The benefits of the coordinated controller structure are demonstrated with transient engine measurements in a passenger car.

Journal ArticleDOI
TL;DR: Mixing characteristics of particles of different volatilities from a diesel engine were studied with two tandem differential mobility analyzers (TDMAs) and an aerosol particle mass analyzer (APM) to validate a simple fitting method that uses two log-normal curves to obtain the mixing ratios.
Abstract: Mixing characteristics of particles of different volatilities from a diesel engine were studied with two tandem differential mobility analyzers (TDMAs) and an aerosol particle mass analyzer (APM). In both TDMA systems, a heater was located in the aerosol path between the first and second DMAs. Diesel exhaust particles that were size-selected in the first DMA were passed through the heater, and the change in particle size due to loss of volatile components was determined by the second DMA. On the basis of the volatility measurements, the particles could be separated into two overlapping modes that varied in peak diameter and magnitude depending on the engine operating conditions. Particles in the smaller size mode were almost completely volatile, while those in the larger size mode contained a nonvolatile core. The TDMA data inversion technique used here allowed accurate determination of the mixing ratios of the two types of particles. These data were in turn used to validate a simple fitting method that u...

Journal ArticleDOI
TL;DR: In this paper, the effects of different fuel cetane numbers (CNs) and fuel injection pressures on a Diesel engine emission and on the performance were investigated. But, no significant increases in engine performance were observed.

Patent
17 Nov 2003
TL;DR: In this article, a fuel processor that efficiently converts added hydrocarbon fuel to a reducing mixture of H2 and CO is presented. But the added fuel may be a portion of the onboard fuel on a vehicle.
Abstract: The invention provides devices and methods for generating H2 and CO in an O2 containing gas stream. The invention also provides devices and methods for removal of NOX from an O2 containing gas stream, particularly the oxygen-rich exhaust stream from a lean-burning engine, such as a diesel engine. The invention includes a fuel processor that efficiently converts added hydrocarbon fuel to a reducing mixture of H2 and CO. the added fuel may be a portion of the onboard fuel on a vehicle. The H2 and CO are incorporated into the exhaust stream and reacted over a selective lean NOX catalyst to convert NOX to N2, thereby providing an efficient means of NOX emission control.

Journal ArticleDOI
İsmet Çelikten1
TL;DR: In this paper, the effects of injection spray pressure on engine performance and exhaust emissions have been investigated on a turbocharger diesel engine with 4-cylinder, 4-stroke, indirect injection.

Proceedings ArticleDOI
03 Mar 2003
TL;DR: In this paper, the complex interactions resulting from the application and control of Exhaust Gas Recirculation (EGR) on a production heavy-duty diesel engine system, and its effectiveness in reducing NOx emissions were studied.
Abstract: This work studies the complex interactions resulting from the application and control of Exhaust Gas Recirculation (EGR) on a production heavy-duty diesel engine system, and its effectiveness in reducing NOx emissions. The coupling between EGR, the Variable Geometry Turbocharger (VGT) and the EGR cooler critically affects boost pressure, air/fuel ratio (A/F), combustion efficiency and pumping work. It is shown that EGR provides an effective means for reducing flame temperatures and NOx emissions, particularly under low A/F ratio conditions. However, engine thermal efficiency tends to decrease with EGR as a result of decreasing indicated work and increasing pumping work. Combustion deterioration is predominant at higher load, low speed and low boost conditions, due to a significant decrease of A/F ratio with increasing EGR. For conditions allowing the VGT to maintain high enough boost and hence A/F ratio, efficiency losses with increased EGR are largely attributed to increased pumping work. Finally, the total system heat rejection increases significantly due to EGR cooling.

Journal ArticleDOI
TL;DR: In this paper, the effect of increasing fuel inlet temperature on viscosity and performance of a single cylinder, unmodified diesel engine was evaluated, and the overall results showed that fuel heating increased peak cylinder pressure and was also beneficial at low speed and under part-load operation.

Journal ArticleDOI
TL;DR: In this article, waste olive oil methyl ester was evaluated as a fuel for diesel engines during a 50-h short-term performance test in a diesel direct-injection Perkins engine.
Abstract: The importance of the recycling of vegetable oils that have been used for frying has led the scientific community to provide viable options; among them is the transesterification in biodiesel. Biodiesel is one of the most popular and accepted diesel-fuel alternatives. In this sense, to gain knowledge about the implications of its use, waste olive oil methyl ester was evaluated as a fuel for diesel engines during a 50-h short-term performance test in a diesel direct-injection Perkins engine. Engine-performance tests indicated a slight power loss and brake-specific fuel consumption increase, although statistical analysis showed no significant differences between biodiesel and No. 2 diesel fuel (EN 590) tests. In this sense, energy conversion efficiency remained constant or showed a slight increase when waste olive oil methyl ester was used instead of No. 2 diesel fuel. Carbon deposits and wear seemed normal. During the test, no difficulties were experienced, in regard to engine starting, and the engine perf...

Journal ArticleDOI
TL;DR: In this article, a 20 percent biodiesel-fuelled engine was evaluated for long-term endurance tests on both diesel and biodiesel, and the results showed substantially lower wear and thus improved life for biodiesel operated engines.
Abstract: The combustion related properties of vegetable oils are somewhat similar to diesel oil Neat vegetable oils or their blends with diesel, however, pose various long-term problems in compression ignition engines, eg, poor atomization characteristics, ring-sticking, injector coking, injector deposits, injector pump failure, and lube oil dilution by crank-case polymerization These undesirable features of vegetable oils are because of their inherent properties like high viscosity, low volatility, and polyunsaturated character Linseed oil methyl ester (LOME) was prepared using methanol for long-term engine operations The physical and combustion-related properties of the fuels thus developed were found to be closer to that of the diesel oil A blend of 20 percent was selected as optimum biodiesel blend Two similar new engines were completely disassembled and subjected to dimensioning of various vital moving parts and then subjected to long-term endurance tests on 20 percent biodiesel blend and diesel oil, respectively After completion of the test, both the engines were again disassembled for physical inspection and wear measurement of various vital parts The physical wear of various vital parts, injector coking, carbon deposits on piston, and ring sticking were found to be substantially lower in case of 20 percent biodiesel-fuelled engine The lubricating oil samples drawn from both engines were subjected to atomic absorption spectroscopy for measurement of various wear metal traces present AAS tests confirmed substantially lower wear and thus improved life for biodiesel operated engines