The Diesel Combustion Collaboratory: Combustion Researchers Collaborating over the Internet

Energy Technology Data Exchange (ETDEWEB)

C. M. Pancerella; L. A. Rahn; C. Yang

2000-02-01

The Diesel Combustion Collaborator (DCC) is a pilot project to develop and deploy collaborative technologies to combustion researchers distributed throughout the DOE national laboratories, academia, and industry. The result is a problem-solving environment for combustion research. Researchers collaborate over the Internet using DCC tools, which include: a distributed execution management system for running combustion models on widely distributed computers, including supercomputers; web-accessible data archiving capabilities for sharing graphical experimental or modeling data; electronic notebooks and shared workspaces for facilitating collaboration; visualization of combustion data; and video-conferencing and data-conferencing among researchers at remote sites. Security is a key aspect of the collaborative tools. In many cases, the authors have integrated these tools to allow data, including large combustion data sets, to flow seamlessly, for example, from modeling tools to data archives. In this paper the authors describe the work of a larger collaborative effort to design, implement and deploy the DCC.

Aspen Simulation of Diesel-Biodiesel Blends Combustion

Directory of Open Access Journals (Sweden)

Pérez-Sánchez Armando

2015-01-01

Full Text Available Biodiesel is a fuel produced by transesterification of vegetable oils or animal fats, which currently is gaining attention as a diesel substitute. It represents an opportunity to reduce CO2, SO2, CO, HC, PAH and PM emissions and contributes to the diversification of fuels in Mexico's energetic matrix. The results of the simulation of the combustion process are presented in this paper with reference to an engine specification KUBOTA D600-B, operated with diesel-biodiesel blends. The physicochemical properties of the compounds and the operating conditions of equipment were developed using the simulator Aspen® and supplementary information. The main aspects of the engine working conditions were considered such as diesel-biodiesel ratio, air/fuel mixture, temperature of the combustion gases and heat load. Diesel physicochemical specifications were taken from reports of PEMEX and SENER. Methyl esters corresponding to the transesterification of fatty acids that comprise castor oil were regarded as representative molecules of biodiesel obtained from chromatographic analysis. The results include CO2, water vapor, combustion efficiency, power and lower calorific value of fuels.

MODELING OF FUEL SPRAY CHARACTERISTICS AND DIESEL COMBUSTION CHAMBER PARAMETERS

Directory of Open Access Journals (Sweden)

G. M. Kukharonak

2011-01-01

Full Text Available The computer model for coordination of fuel spray characteristics with diesel combustion chamber parameters has been created in the paper.  The model allows to observe fuel sprays  develоpment in diesel cylinder at any moment of injection, to calculate characteristics of fuel sprays with due account of a shape and dimensions of a combustion chamber, timely to change fuel injection characteristics and supercharging parameters, shape and dimensions of a combustion chamber. Moreover the computer model permits to determine parameters of holes in an injector nozzle that provides the required fuel sprays characteristics at the stage of designing a diesel engine. Combustion chamber parameters for 4ЧН11/12.5 diesel engine have been determined in the paper.

Experimental and Numerical Study of Jet Controlled Compression Ignition on Combustion Phasing Control in Diesel Premixed Compression Ignition Systems

OpenAIRE

Qiang Zhang; Wuqiang Long; Jiangping Tian; Yicong Wang; Xiangyu Meng

2014-01-01

In order to directly control the premixed combustion phasing, a Jet Controlled Compression Ignition (JCCI) for diesel premixed compression ignition systems is investigated. Experiments were conducted on a single cylinder natural aspirated diesel engine without EGR at 3000 rpm. Numerical models were validated by load sweep experiments at fixed spark timing. Detailed combustion characteristics were analyzed based on the BMEP of 2.18 bar. The simulation results showed that the high temperature j...

Diesel oil combustion in fluidized bed; Combustion de aceite diesel en lecho fluidizado

Energy Technology Data Exchange (ETDEWEB)

Rodriguez Cazares, Mario [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

1992-07-01

The effect of the fluidized bed depth in the combustion in burning diesel oil in a fluidized bed, was analyzed. A self sustained combustion was achieved injecting the oil with an injector that utilized a principle similar to an automobile carburetor venturi. Three different depths were studied and it was found that the deeper the bed, the greater the combustion efficiency. Combustion efficiencies were attained from 82% for a 100mm bed depth, up to 96% for a 200mm bed depth. The diminution in the efficiency was mainly attributed to unburned hydrocarbons and to the carbon carried over, which was observed in the black smoke at the stack outlet. Other phenomena registered were the temperature gradient between the lower part of the bed and the upper part, caused by the fluidization velocity; additionally it was observed that the air employed for the oil injection (carbureting air) is the most important parameter to attain a complete combustion. [Espanol] Se analizo el efecto de la profundidad del lecho en la combustion al quemar aceite diesel en un lecho fluidizado experimental. Se logro combustion autosostenida inyectando el aceite con un inyector que utilizo un principio similar al venturi del carburador de automovil. Se estudiaron tres diferentes profundidades del lecho y se encontro que a mayor profundidad del lecho, mayor eficiencia de la combustion. Se lograron eficiencias de la combustion desde 82% para el lecho de 100 mm de profundidad hasta 96% para el de 200 mm. La disminucion de la eficiencia se atribuyo, principalmente, a los hidrocarburos no quemados y al carbon arrastrado, lo cual se observo en el humo negro a la salida de la chimenea. Otros fenomenos registrados fueron el gradiente de temperatura entre la parte baja del lecho y la parte superior causado por la velocidad de fluidizacion; ademas, se observo que el aire utilizado para inyectar el aceite (aire de carburacion) es el parametro mas importante para lograr una combustion completa.

Soot temperature and KL factor for biodiesel and diesel spray combustion in a constant volume combustion chamber

KAUST Repository

Zhang, Ji

2013-07-01

This paper presents measurements of the soot temperature and KL factor for biodiesel and diesel combustion in a constant volume chamber using a two-color technique. This technique uses a high-speed camera coupled with two narrowband filters (550. nm and 650. nm, 10. nm FWHM). After calibration, statistical analysis shows that the uncertainty of the two-color temperature is less than 5%, while it is about 50% for the KL factor. This technique is then applied to the spray combustion of biodiesel and diesel fuels under an ambient oxygen concentration of 21% and ambient temperatures of 800, 1000 and 1200. K. The heat release result shows higher energy utilization efficiency for biodiesel compared to diesel under all conditions; meanwhile, diesel shows a higher pressure increase due to its higher heating value. Biodiesel yields a lower temperature inside the flame area, a longer soot lift-off length, and a smaller soot area compared to diesel. Both the KL factor and the total soot with biodiesel are lower than with diesel throughout the entire combustion process, and this difference becomes larger as the ambient temperature decreases. Biodiesel shows approximately 50-100. K lower temperatures than diesel at the quasi-steady stage for 1000 and 1200. K ambient temperature, while diesel shows a lower temperature than biodiesel at 800. K ambient. This result may raise the question of how important the flame temperature is in explaining the higher NO. x emissions often observed during biodiesel combustion. Other factors may also play an important role in controlling NO. x emissions. Both biodiesel and diesel temperature measurements show a monotonic dependence on the ambient temperature. However, the ambient temperature appears to have a more significant effect on the soot formation and oxidation in diesel combustion, while biodiesel combustion soot characteristics shows relative insensitivity to the ambient temperature. © 2013 Elsevier Ltd.

Injection and Combustion of RME with Water Emulsions in a Diesel Engine

Directory of Open Access Journals (Sweden)

J. Cisek

2010-01-01

Full Text Available This paper presents ways of using the fully-digitised triggerable AVL VideoScope 513D video system for analysing the injection and combustion inside a diesel engine cylinder fuelled by RME with water emulsions.The research objects were: standard diesel fuel, rapeseed methyl ester (RME and RME – water emulsions. With the aid of a helical flow reactor, stable emulsions with the water fraction up to 30 % weight were obtained, using an additive to prevent the water from separating out of the emulsion.An investigation was made of the effect of the emulsions on exhaust gas emissions (NOX, CO and HC, particulate matter emissions, smoke and the fuel consumption of a one-cylinder HD diesel engine with direct injection. Additionally, the maximum cylinder pressure rise was calculated from the indicator diagram. The test engine was operated at a constant speed of 1 600 rpm and 4 bar BMEP load conditions. The fuel injection and combustion processes were observed and analysed using endoscopes and a digital camera. The temperature distribution in the combustion chamber was analysed quantitatively using the two-colour method. The injection and combustion phenomena were described and compared.A way to reduce NOX formation in the combustion chamber of diesel engines by adding water in the combustion zone was presented. Evaporating water efficiently lowers the peak flame temperature and the temperature in the post-flame zone. For diesel engines, there is an exponential relationship between NOX emissions and peak combustion temperatures. The energy needed to vaporize the water results in lower peak temperatures of the combusted gases, with a consequent reduction in nitrogen oxide formation. The experimental results show up to 50 % NOX emission reduction with the use of 30% water in an RME emulsion, with unchanged engine performance.

Effect of ethanol/water blends addition on diesel fuel combustion in RCM and DI diesel engine

International Nuclear Information System (INIS)

Nour, Mohamed; Kosaka, Hidenori; Sato, Susumu; Bady, Mahmoud; Abdel-Rahman, Ali K.; Uchida, Kenta

2017-01-01

Highlights: • Effect of ethanol/water addition on diesel combustion studied using optical diagnostics. • The addition of water to ethanol improves engine combustion and soot oxidation. • Ethanol/water injection into exhaust manifold eliminates their endothermic effect. • Ethanol with high water content is recommended for better engine combustion. • Soot concentration reduced by 50% and NO x emissions reduced by 88%. - Abstract: The effect of ethanol/water blends addition on diesel fuel combustion and emissions is investigated experimentally in this study using optical diagnostics. Basic study is performed using rapid compression machine (RCM) under CI conditions. The tested ethanol energy fractions varied in the range of 10–40% of the total added fuel energy, while water volume ratios varied in the range of 10–40% of the injected ethanol. Ethanol and water were evaporated before entering the combustion chamber to eliminate their endothermic effect. Results reveal that addition of ethanol/water blends to diesel fuel results in longer ignition delay and promote the apparent heat release rate (AHRR) at the premixed combustion phase compared to absolute ethanol addition. Additionally, soot and NO x emissions are reduced with ethanol/water addition compared to absolute ethanol addition and neat diesel combustion. The basic study is then extended to investigate the effect ethanol/water blends addition on diesel fuel combustion using single cylinder diesel engine. Waste heat in exhaust manifold is utilized to vaporize ethanol/water blends before combustion. Results reveal that ethanol/water blends injection leads to increase in peak cylinder pressure, indicated mean effective pressure (IMEP), and AHRR at premixed combustion phase. Additionally, the ignition delay increased with ethanol/water addition. NO x emission is decreased up to 88% along with a reduction in soot by 50%. The lower ethanol to water volume ratios show better combustion efficiency, IMEP

Numerical analysis on the effect of swirl ratios on swirl chamber combustion system of DI diesel engines

International Nuclear Information System (INIS)

Wei, Shengli; Wang, Feihu; Leng, Xianyin; Liu, Xin; Ji, Kunpeng

2013-01-01

Highlights: • A new swirl chamber combustion system of DI diesel engines is proposed. • The appropriate vortex motion can reduce the wall concentration of mixture. • It has best emissions at swirl ratio of 0.8. • Before spray, the turbulent kinetic energy is primarily controlled by the squish. • After spray, the combustion swirl and reverse squish have a great impact on TKE. - Abstract: In order to improve the spray spatial distribution and promote the mixture quality, enhancing airflow movement in a combustion chamber, a new swirl chamber combustion system in direct injection (DI) diesel engines is proposed. The mixture formation and combustion progress in the cylinder are simulated and investigated at several different swirl ratios by using the AVL-FIRE code. The results show that in view of the fuel/air equivalence ratio distribution, the uniformity of mixture with swirl ratio of 0.2 is better. Before spray injection, the turbulent kinetic energy distribution is primarily controlled by the squish. After spray, the combustion swirl and reverse squish swirl have an effect on temperature distribution and turbulent kinetic energy (TKE) in the cylinder. The NO mass fraction is the lowest at swirl ratio of 0.8 and the highest at swirl ratio of 2.7, while Soot mass fraction is the lowest at swirl ratio of 0.2 and the highest at swirl ratio of 3.2. The appropriate swirl is benefit to improve combustion. To sum up, the emissions at swirl ratio of 0.8 has a better performance in the new combustion system

Multi-zone modeling of combustion and emissions formation in DI diesel engine operating on ethanol-diesel fuel blends

International Nuclear Information System (INIS)

Rakopoulos, C.D.; Antonopoulos, K.A.; Rakopoulos, D.C.; Hountalas, D.T.

2008-01-01

A multi-zone model for calculation of the closed cycle of a direct injection (DI) diesel engine is applied for the interesting case of its operation with ethanol-diesel fuel blends, the ethanol (bio-fuel) being considered recently as a promising extender to petroleum distillates. Although there are many experimental studies, there is an apparent scarcity of theoretical models scrutinizing the formation mechanisms of combustion generated emissions when using bio-fuels. This is a two dimensional, multi-zone model with the issuing fuel jets divided into several discrete volumes, called 'zones', formed along and across the direction of the fuel injection. The model follows each zone, with its own time history, as the spray penetrates into the swirling air environment of the combustion chamber. Droplet evaporation and jet mixing models are used to determine the amount of fuel and entrained air in each zone available for combustion. The mass, energy and state equations are applied in each zone to provide local temperatures and cylinder pressure histories. The concentrations of the various constituents are calculated by adopting a chemical equilibrium scheme for the C-H-O-N system of eleven species considered, together with chemical rate equations for calculation of nitric oxide (NO) and a model for net soot formation. The results from the computer program, implementing the analysis, for the in cylinder pressure, exhaust NO concentration and soot density compare well with the corresponding measurements from an experimental investigation conducted on a fully automated test bed, standard 'Hydra', DI diesel engine located at the authors' laboratory, which is operated with ethanol-diesel fuel blends containing 5%, 10% and 15% (by vol.) ethanol. Iso-contour plots of equivalence ratio, temperature, NO and soot inside the cylinder at various instants of time, when using these ethanol-diesel fuel blends against the diesel fuel (baseline fuel), shed light on the mechanisms

Impact of low temperature combustion attaining strategies on diesel engine emissions for diesel and biodiesels: A review

International Nuclear Information System (INIS)

Imtenan, S.; Varman, M.; Masjuki, H.H.; Kalam, M.A.; Sajjad, H.; Arbab, M.I.; Rizwanul Fattah, I.M.

2014-01-01

Highlights: • Various low-temperature combustion strategies have been discussed briefly. • Effect on emissions has been discussed under low temperature combustion strategies. • Low-temperature combustion reduces NO x and PM simultaneously. • Higher CO, HC emissions with lower performance are the demerits of these strategies. • Biodiesels are also potential to attain low temperature combustion conditions. - Abstract: Simultaneous reduction of particulate matter (PM) and nitrogen oxides (NO x ) emissions from diesel exhaust is the key to current research activities. Although various technologies have been introduced to reduce emissions from diesel engines, the in-cylinder reduction techniques of PM and NO x like low temperature combustion (LTC) will continue to be an important field in research and development of modern diesel engines. Furthermore, increasing prices and question over the availability of diesel fuel derived from crude oil have introduced a growing interest. Hence it is most likely that future diesel engines will be operated on pure biodiesel and/or blends of biodiesel and crude oil-based diesel. Being a significant technology to reduce emissions, LTC deserves a critical analysis of emission characteristics for both diesel and biodiesel. This paper critically investigates both petroleum diesel and biodiesel emissions from the view point of LTC attaining strategies. Due to a number of differences of physical and chemical properties, petroleum diesel and biodiesel emission characteristics differ a bit under LTC strategies. LTC strategies decrease NO x and PM simultaneously but increase HC and CO emissions. Recent attempts to attain LTC by biodiesel have created a hope for reduced HC and CO emissions. Decreased performance issue during LTC is also being taken care of by latest ideas. However, this paper highlights the emissions separately and analyzes the effects of significant factors thoroughly under LTC regime

Performance, Emissions and Combustion Characteristics of a Single Cylinder Diesel Engine Fuelled with Blends of Jatropha Methyl Ester and Diesel

Directory of Open Access Journals (Sweden)

Debasish Padhee

2014-05-01

Full Text Available In order to meet the energy requirements, there has been growing interest in alternative fuels like biodiesels, ethyl alcohol, biogas, hydrogen and producer gas to provide a suitable diesel substitute for internal combustion engines. An experimental investigation was performed to study the performance, emissions and combustion characteristics of diesel engine fuelled with blends of Jatropha methyl ester and diesel. In the present work three different fuel blends of Jatropha methyl ester (B10, B20, B40 and B100 were used. The increments in load on the engine increase the brake thermal efficiency, exhaust gas temperature and lowered the brake specific fuel consumption. The biodiesel blends produce lower carbon monoxide & unburned hydrocarbon emission and higher carbon dioxide & oxides of nitrogen than neat diesel fuel. From the results it was observed that the ignition delays decreased with increase in concentration of biodiesel in biodiesel blends with diesel. The combustion characteristics of single-fuel for biodiesel and diesel have similar combustion pressure and HRR patterns at different engine loads but it was observed that the peak cylinder pressure and heat release rate were lower for biodiesel blends compared to those of diesel fuel combustion.

Combustion of soybean oil and diesel mixtures for heating purposes

Energy Technology Data Exchange (ETDEWEB)

Guimaraes, Adriana Correa; Sanz, Jose Francisco [European University Miguel de Cervantes, Valladolid (Spain)], E-mail: acorrea@uemc.es; Hernandez, Salvador; Navas, Luis Manuel; Rodriguez, Elena; Ruiz, Gonzalo [University of Valladolid (Spain). Dept. of Agricultural and Forest Engineering; San Jose, Julio [University of Valladolid (Spain). Dept. of Energetic Engineering; Gomez, Jaime [University of Valladolid (Spain). Dept. of Communications and Signal Theory and Telematics Engineering

2008-07-01

Using blends of vegetable oils with petroleum derivates for heating purposes has several advantages over other energy application for vegetable oils. This paper presents the results of an investigation by use of soybean oil and diesel mixture as fuel for producing heat in conventional diesel installation. The paper is set out as follows: properties characterization of soybean oil as fuel and of diesel oil, as well as the mixture of both; selection of the mixture according to their physical chemical properties and how they adapt to conventional combustion installation; experimentation with the selected mixture, allowing the main combustion parameters to be measured; processing the collected data, values of combustion, efficiency and reduction of emissions. Conclusions show that the use of soybean oil and diesel mixture for producing heat energy in conventional equipment is feasible and beneficial for reduction emissions. (author)

Construction of combustion models for rapeseed methyl ester bio-diesel fuel for internal combustion engine applications.

Science.gov (United States)

Golovitchev, Valeri I; Yang, Junfeng

2009-01-01

Bio-diesel fuels are non-petroleum-based diesel fuels consisting of long chain alkyl esters produced by the transesterification of vegetable oils, that are intended for use (neat or blended with conventional fuels) in unmodified diesel engines. There have been few reports of studies proposing theoretical models for bio-diesel combustion simulations. In this study, we developed combustion models based on ones developed previously. We compiled the liquid fuel properties, and the existing detailed mechanism of methyl butanoate ester (MB, C(5)H(10)O(2)) oxidation was supplemented by sub-mechanisms for two proposed fuel constituent components, C(7)H(16) and C(7)H(8)O (and then, by mp2d, C(4)H(6)O(2) and propyne, C(3)H(4)) to represent the combustion model for rapeseed methyl ester described by the chemical formula, C(19)H(34)O(2) (or C(19)H(36)O(2)). The main fuel vapor thermal properties were taken as those of methyl palmitate C(19)H(36)O(2) in the NASA polynomial form of the Burcat database. The special global reaction was introduced to "crack" the main fuel into its constituent components. This general reaction included 309 species and 1472 reactions, including soot and NO(x) formation processes. The detailed combustion mechanism was validated using shock-tube ignition-delay data under diesel engine conditions. For constant volume and diesel engine (Volvo D12C) combustion modeling, this mechanism could be reduced to 88 species participating in 363 reactions.

Monitoring of diesel engine combustions based on the acoustic source characterisation of the exhaust system

Science.gov (United States)

Jiang, J.; Gu, F.; Gennish, R.; Moore, D. J.; Harris, G.; Ball, A. D.

2008-08-01

Acoustic methods are among the most useful techniques for monitoring the condition of machines. However, the influence of background noise is a major issue in implementing this method. This paper introduces an effective monitoring approach to diesel engine combustion based on acoustic one-port source theory and exhaust acoustic measurements. It has been found that the strength, in terms of pressure, of the engine acoustic source is able to provide a more accurate representation of the engine combustion because it is obtained by minimising the reflection effects in the exhaust system. A multi-load acoustic method was then developed to determine the pressure signal when a four-cylinder diesel engine was tested with faults in the fuel injector and exhaust valve. From the experimental results, it is shown that a two-load acoustic method is sufficient to permit the detection and diagnosis of abnormalities in the pressure signal, caused by the faults. This then provides a novel and yet reliable method to achieve condition monitoring of diesel engines even if they operate in high noise environments such as standby power stations and vessel chambers.

A new hybrid pneumatic combustion engine to improve fuel consumption of wind–Diesel power system for non-interconnected areas

International Nuclear Information System (INIS)

Basbous, Tammam; Younes, Rafic; Ilinca, Adrian; Perron, Jean

2012-01-01

Highlights: ► We model thermodynamic ideal cycle of a new hybrid pneumaticcombustion engine. ► We optimize commands of all modes and calculate maps of fuel and air consumption. ► We evaluate fuel economy for Wind–Diesel system function of tank volume and wind penetration. ► We find up to 10% of fuel economy i.e. 80 t/year with 100% wind penetration. ► Fuel economy increases with wind penetration and with volume but has asymptotic value. -- Abstract: This paper presents an evaluation of an optimized Hybrid Pneumatic-Combustion Engine (HPCE) concept that permits reducing fuel consumption for electricity production in non-interconnected remote areas, originally equipped with hybrid Wind–Diesel System (WDS). Up to now, most of the studies on the pneumatic hybridization of Internal Combustion Engines (ICE) have dealt with two-stroke pure pneumatic mode. The few studies that have dealt with hybrid pneumatic-combustion four-stroke mode require adding a supplementary valve to charge compressed air in the combustion chamber. This modification means that a new cylinder head should be fabricated. Moreover, those studies focus on spark ignition engines and are not yet validated for Diesel engines. Present HPCE is capable of making a Diesel engine operate under two-stroke pneumatic motor mode, two-stroke pneumatic pump mode and four-stroke hybrid mode, without needing an additional valve in the combustion chamber. This fact constitutes this study’s strength and innovation. The evaluation of the concept is based on ideal thermodynamic cycle modeling. The optimized valve actuation timings for all modes lead to generic maps that are independent of the engine size. The fuel economy is calculated for a known site during a whole year, function of the air storage volume and the wind power penetration rate.

Spray combustion of biomass-based renewable diesel fuel using multiple injection strategy in a constant volume combustion chamber

KAUST Repository

Jing, Wei; Wu, Zengyang; Roberts, William L.; Fang, Tiegang

2016-01-01

Effect of a two-injection strategy associated with a pilot injection on the spray combustion process was investigated under conventional diesel combustion conditions (1000 K and 21% O2 concentration) for a biomass-based renewable diesel fuel, i

Experimental analysis of ethanol dual-fuel combustion in a heavy-duty diesel engine: An optimisation at low load

International Nuclear Information System (INIS)

Pedrozo, Vinícius B.; May, Ian; Dalla Nora, Macklini; Cairns, Alasdair; Zhao, Hua

2016-01-01

Highlights: • Dual-fuel combustion offers promising results on a stock heavy-duty diesel engine. • The use of split diesel injections extends the benefits of the dual-fuel mode. • Ethanol–diesel dual-fuel combustion results in high indicated efficiencies. • NOx and soot emissions are significantly reduced. • Combustion efficiency reaches 98% with an ethanol energy ratio of 53%. - Abstract: Conventional diesel combustion produces harmful exhaust emissions which adversely affect the air quality if not controlled by in-cylinder measures and exhaust aftertreatment systems. Dual-fuel combustion can potentially reduce the formation of nitrogen oxides (NOx) and soot which are characteristic of diesel diffusion flame. The in-cylinder blending of different fuels to control the charge reactivity allows for lower local equivalence ratios and temperatures. The use of ethanol, an oxygenated biofuel with high knock resistance and high latent heat of vaporisation, increases the reactivity gradient. In addition, renewable biofuels can provide a sustainable alternative to petroleum-based fuels as well as reduce greenhouse gas emissions. However, ethanol–diesel dual-fuel combustion suffers from poor engine efficiency at low load due to incomplete combustion. Therefore, experimental studies were carried out at 1200 rpm and 0.615 MPa indicated mean effective pressure on a heavy-duty diesel engine. Fuel delivery was in the form of port fuel injection of ethanol and common rail direct injection of diesel. The objective was to improve combustion efficiency, maximise ethanol substitution, and minimise NOx and soot emissions. Ethanol energy fractions up to 69% were explored in conjunction with the effect of different diesel injection strategies on combustion, emissions, and efficiency. Optimisation tests were performed for the optimum fuelling and diesel injection strategy. The resulting effects of exhaust gas recirculation, intake air pressure, and rail pressure were

Effect of Alcohol on Diesel Engine Combustion Operating with Biodiesel-Diesel Blend at Idling Conditions

Science.gov (United States)

Mahmudul, H. M.; Hagos, Ftwi. Y.; A, M. Mukhtar N.; Mamat, Rizalman; Abdullah, A. Adam

2018-03-01

Biodiesel is a promising alternative fuel to run the automotive engine. However, its blends have not been properly investigated during idling as it is the main problem to run the vehicles in a big city. The purpose of this study is to evaluate the impact of alcohol additives such as butanol and ethanol on combustion parameters under idling conditions when a single cylinder diesel engine operates with diesel, diesel-biodiesel blends, and diesel biodiesel-alcohol blends. The engine combustion parameters such as peak pressure, heat release rate and ignition delay were computed. This investigation has revealed that alcohol blends with diesel and biodiesel, BU20 blend yield higher maximum peak cylinder pressure than diesel. B5 blend was found with the lowest energy release among all. B20 was slightly lower than diesel. BU20 blend was seen with the highest peak energy release where E20 blend was found advance than diesel. Among all, the blends alcohol component revealed shorter ignition delay. B5 and B20 blends were influenced by biodiesel interference and the burning fraction were found slightly slower than conventional diesel where BU20 and E20 blends was found slightly faster than diesel So, based on the result, it can be said that among the alcohol blends butanol and ethanol can be promising alternative at idling conditions and can be used without any engine modifications.

Ethanol-fueled low temperature combustion: A pathway to clean and efficient diesel engine cycles

International Nuclear Information System (INIS)

Asad, Usman; Kumar, Raj; Zheng, Ming; Tjong, Jimi

2015-01-01

Highlights: • Concept of ethanol–diesel fueled Premixed Pilot Assisted Combustion (PPAC). • Ultra-low NOx and soot with diesel-like thermal efficiency across the load range. • Close to TDC pilot injection timing for direct combustion phasing control. • Minimum pilot quantity (15% of total energy input) for clean, stable operation. • Defined heat release profile distribution (HRPD) to optimize pilot-ethanol ratio. - Abstract: Low temperature combustion (LTC) in diesel engines offers the benefits of ultra-low NOx and smoke emissions but suffers from lowered energy efficiency due to the high reactivity and low volatility of diesel fuel. Ethanol from renewable biomass provides a viable alternate to the petroleum based transportation fuels. The high resistance to auto-ignition (low reactivity) and its high volatility make ethanol a suitable fuel for low temperature combustion (LTC) in compression-ignition engines. In this work, a Premixed Pilot Assisted Combustion (PPAC) strategy comprising of the port fuel injection of ethanol, ignited with a single diesel pilot injection near the top dead centre has been investigated on a single-cylinder high compression ratio diesel engine. The impact of the diesel pilot injection timing, ethanol to diesel quantity ratio and exhaust gas recirculation on the emissions and efficiency are studied at 10 bar IMEP. With the lessons learnt, successful ethanol–diesel PPAC has been demonstrated up to a load of 18 bar IMEP with ultra-low NOx and soot emissions across the full load range. The main challenge of PPAC is the reduced combustion efficiency especially at low loads; therefore, the authors have presented a combustion control strategy to allow high efficiency, clean combustion across the load range. This work entails to provide a detailed framework for the ethanol-fueled PPAC to be successfully implemented.

Investigation of Bio-Diesel Fueled Engines under Low-Temperature Combustion Strategies

Energy Technology Data Exchange (ETDEWEB)

Chia-fon F. Lee; Alan C. Hansen

2010-09-30

In accordance with meeting DOE technical targets this research was aimed at developing and optimizing new fuel injection technologies and strategies for the combustion of clean burning renewable fuels in diesel engines. In addition a simultaneous minimum 20% improvement in fuel economy was targeted with the aid of this novel advanced combustion system. Biodiesel and other renewable fuels have unique properties that can be leveraged to reduce emissions and increase engine efficiency. This research is an investigation into the combustion characteristics of biodiesel and its impacts on the performance of a Low Temperature Combustion (LTC) engine, which is a novel engine configuration that incorporates technologies and strategies for simultaneously reducing NOx and particulate emissions while increasing engine efficiency. Generating fundamental knowledge about the properties of biodiesel and blends with petroleum-derived diesel and their impact on in-cylinder fuel atomization and combustion processes was an important initial step to being able to optimize fuel injection strategies as well as introduce new technologies. With the benefit of this knowledge experiments were performed on both optical and metal LTC engines in which combustion and emissions could be observed and measured under realistic conditions. With the aid these experiments and detailed combustion models strategies were identified and applied in order to improve fuel economy and simultaneously reduce emissions.

Numerical Modeling of Diesel Spray Formation and Combustion

NARCIS (Netherlands)

Bekdemir, C.; Somers, L.M.T.; Goey, de L.P.H.

2009-01-01

A study is presented on the modeling of fuel sprays in diesel engines. The objective of this study is in the first place to accurately and efficiently model non-reacting diesel spray formation, and secondly to include ignition and combustion. For that an efficient 1D Euler-Euler spray model [21] is

Emission and combustion characteristics of multiple stage diesel combustion; Nidan nensho ni yoru diesel kikan no nensho to haishutsubutsu tokusei

Energy Technology Data Exchange (ETDEWEB)

Hashizume, T; Miyamoto, T; Tsujimura, K [New A.C.E. Institute Co. Ltd., Tokyo (Japan); Kobayashi, S; Shimizu, K [Japan Automobile Research Institute, Tsukuba (Japan)

1997-10-01

A new concept of multiple stage diesel combustion was studied by means of engine test, combustion observation and numerical simulation, in order to reduce NOx emissions at high load conditions. With this concept, the premixed combustion occurs under the fuel lean conditions and the diffusion combustion occurs under the high temperature conditions. As seen in the result of combustion observation, a first stage combustion occurs with no luminous flame. A second stage combustion occurs with a luminous flame after very short ignition delay period. However the luminous flame is disappeared immediately. Because cylinder temperature is high, and hence soot oxidizes immediately. 5 refs., 11 figs., 1 tab.

Spray combustion of Jet-A and diesel fuels in a constant volume combustion chamber

KAUST Repository

Jing, Wei

2015-01-01

This work investigates the spray combustion of Jet-A fuel in an optical constant-volume combustion chamber under different ambient initial conditions. Ambient temperature was varied at 800 K, 1000 K, and 1200 K and five different ambient O2 concentrations were used, spanning 10-21%. These ambient conditions can be used to mimic practical diesel engine working conditions under different fuel injection timings and exhaust gas recirculation (EGR) levels. Both transient and quasi-steady state analyses were conducted. The transient analysis focused on the flame development from the beginning to the end of the combustion process, illustrating how the flame structure evolves with time. The quasi-steady state analysis concentrated on the stable flame structure and compared the flame emissions in terms of spatially integrated intensity, flame effective area, and intensity per pixel. The transient analysis was based on measurements using high-speed imaging of both OH∗ chemiluminescence and broadband natural luminosity (NL). For the quasi-steady state analysis, three flame narrow-band emissions (OH∗ at 310 nm, Band A at 430 nm and Band B at 470 nm) were captured using an ICCD camera. Based on the current Jet-A data and diesel data obtained from previous experiments, a comparison between Jet-A and diesel was made in terms of flame development during the transient state and spatially integrated intensity, flame effective area, and intensity per pixel during the quasi-steady state. For the transient results, Jet-A shares a similar flame development trend to diesel, but featuring a narrower region of NL and a wider region of OH∗ with the increase of ambient temperature and O2 concentration. The soot cloud is oxidized more quickly for Jet-A than diesel at the end of combustion, evident by comparing the area of NL, especially under high O2 concentration. The quasi-steady state results suggest that soot is oxidized effectively under high O2 concentration conditions by the

Smoke reduction using multiple stage diesel combustion; Nidan nensho ni yoru diesel kikan no smoke teigen koka

Energy Technology Data Exchange (ETDEWEB)

Tsujimura, K. [Chiba Institute of Technology, Chiba (Japan); Hashizume, T.; Miyamoto, T.; Akagawa, H.

1999-09-25

A new diesel combustion concept termed MULDIC (MULtiple stage Diesel Combustion), which can reduce NO{sub x} emissions at high load conditions, was studied by means of engine test, combustion observation and numerical simulation. The engine test showed that simultaneous reduction of NO{sub x} and smoke could be obtained with MULDIC operation. In-cylinder combustion observation was carried out in order to clarify the cause of the smoke reduction of the MULDIC. In these photographs, a first stage combustion sins observed with nonluminous flame. In a second stage combustion, a highly sooting luminous flame was observed because the ignition delay was short. However this luminous flame disappeared quickly. Computational results showed that, oxygen is distributed evenly in the cylinder in later portion of the second stage combustion. Moreover, since cylinder temperature was very high, most of the soot oxidized rapidly. Thus, low smoke combustion was obtained. (author)

Oxygenated palm biodiesel: Ignition, combustion and emissions quantification in a light-duty diesel engine

International Nuclear Information System (INIS)

Chong, Cheng Tung; Ng, Jo-Han; Ahmad, Solehin; Rajoo, Srithar

2015-01-01

Highlights: • Diesel engine test using palm biodiesel and diesel at varying speed and load. • Palm biodiesel shows better performance at late stage of cycle evolution. • Oxygen in palm biodiesel fuel improves local combustion at late stage of combustion. • Emissions of NO are lower at low and medium operating speed for palm biodiesel. • Formulation of trend guide for performance and emissions characteristics for light-duty diesel engines. - Abstract: This paper presents an investigation of oxygenated neat palm biodiesel in a direct injection single cylinder diesel engine in terms of ignition, combustion and emissions characteristics. Conventional non-oxygenated diesel fuel is compared as baseline. The engine testing is performed between the operating speed of 2000–3000 rpm and load of up to 3 bar of brake mean effective pressure. From it, a total of 50 experiment cases are tested to form a comprehensive operational speed-load contour map for ignition and combustion; while various engine-out emissions such as NO, CO, UHCs and CO 2 are compared based on fuel type-speed combinations. The ignition and combustion evolution contour maps quantify the absolute ignition delay period and elucidate the difference between that of palm biodiesel and fossil diesel. Although diesel has shorter ignition delay period by up to 0.6 CAD at 3000 rpm and burns more rapidly at the start of combustion, combustion of palm biodiesel accelerates during the mid-combustion phase and overtakes diesel in the cumulative heat release rates (HRR) prior to the 90% cumulative HRR. This can be attributed to the oxygen contained in palm biodiesel assisting in localized regions of combustion. In terms of performance, the oxygenated nature of palm biodiesel provided mixed performances with improved thermal efficiency and increased brake specific fuel consumption, due to the improved combustion and lower calorific values, respectively. Emission measurements show that NO for palm biodiesel is

Influence of low-temperature combustion and dimethyl ether-diesel blends on performance, combustion, and emission characteristics of common rail diesel engine: a CFD study.

Science.gov (United States)

Lamani, Venkatesh Tavareppa; Yadav, Ajay Kumar; Narayanappa, Kumar Gottekere

2017-06-01

Due to presence of more oxygen, absence of carbon-carbon (C-C) bond in chemical structure, and high cetane number of dimethyl ether (DME), pollution from DME operated engine is less compared to diesel engine. Hence, the DME can be a promising alternative fuel for diesel engine. The present study emphasizes the effect of various exhaust gas recirculation (EGR) rates (0-20%) and DME/Diesel blends (0-20%) on combustion characteristics and exhaust emissions of common rail direct injection (CRDI) engine using three-dimensional computational fluid dynamics (CFD) simulation. Extended coherent flame model-3 zone (ECFM-3Z) is implemented to carry out combustion analysis, and k-ξ-f model is employed for turbulence modeling. Results show that in-cylinder pressure marginally decreases with employing EGR compared to without EGR case. As EGR rate increases, nitrogen oxide (NO) formation decreases, whereas soot increases marginally. Due to better combustion characteristics of DME, indicated thermal efficiency (ITE) increases with the increases in DME/diesel blend ratio. Adverse effect of EGR on efficiency for blends is less compared to neat diesel, because the anoxygenated region created due to EGR is compensated by extra oxygen present in DME. The trade-off among NO, soot, carbon monoxide (CO) formation, and efficiency is studied by normalizing the parameters. Optimum operating condition is found at 10% EGR rate and 20% DME/diesel blend. The maximum indicated thermal efficiency was observed for DME/diesel ratio of 20% in the present range of study. Obtained results are validated with published experimental data and found good agreement.

Study of turbocharged diesel engine operation, pollutant emissions and combustion noise radiation during starting with bio-diesel or n-butanol diesel fuel blends

International Nuclear Information System (INIS)

Rakopoulos, C.D.; Dimaratos, A.M.; Giakoumis, E.G.; Rakopoulos, D.C.

2011-01-01

Highlights: → Turbocharged diesel engine emissions during starting with bio-diesel or n-butanol diesel blends. → Peak pollutant emissions due to turbo-lag. → Significant bio-diesel effects on combustion behavior and stability. → Negative effects on NO emissions for both blends. → Positive effects on smoke emissions only for n-butanol blend. -- Abstract: The control of transient emissions from turbocharged diesel engines is an important objective for automotive manufacturers, as stringent criteria for exhaust emissions must be met. Starting, in particular, is a process of significant importance owing to its major contribution to the overall emissions during a transient test cycle. On the other hand, bio-fuels are getting impetus today as renewable substitutes for conventional fuels, especially in the transport sector. In the present work, experimental tests were conducted at the authors' laboratory on a bus/truck, turbocharged diesel engine in order to investigate the formation mechanisms of nitric oxide (NO), smoke, and combustion noise radiation during hot starting for various alternative fuel blends. To this aim, a fully instrumented test bed was set up, using ultra-fast response analyzers capable of capturing the instantaneous development of emissions as well as various other key engine and turbocharger parameters. The experimental test matrix included three different fuels, namely neat diesel fuel and two blends of diesel fuel with either bio-diesel (30% by vol.) or n-butanol (25% by vol.). With reference to the neat diesel fuel case during the starting event, the bio-diesel blend resulted in deterioration of both pollutant emissions as well as increased combustion instability, while the n-butanol (normal butanol) blend decreased significantly exhaust gas opacity but increased notably NO emission.

Energy efficiency impact of EGR on organizing clean combustion in diesel engines

International Nuclear Information System (INIS)

Divekar, Prasad S.; Chen, Xiang; Tjong, Jimi; Zheng, Ming

2016-01-01

Highlights: • Studied EGR impact on efficiency and emissions of diesel and dual-fuel combustion. • Quantified effectiveness of intake dilution for NOx reduction using EGR. • Identified suitable EGR ranges for mitigating emissions–efficiency trade-off. • Developed careful control of intake dilution and in-cylinder excess ratio. • Enabled ultra-low NOx in both diesel and dual-fuel combustion via EGR control. - Abstract: Exhaust gas recirculation (EGR) is a commonly recognized primary technique for reducing NOx emissions in IC engines. However, depending on the extent of its use, the application of EGR in diesel engines is associated with an increase in smoke emissions and a reduction in thermal efficiency. In this work, empirical investigations and parametric analyses are carried out to assess the impact of EGR in attaining ultra-low NOx emissions while minimizing the smoke and efficiency penalties. Two fuelling strategies are studied, namely diesel-only injection and dual-fuel injection. In the dual-fuel strategy, a high volatility liquid fuel is injected into the intake ports, and a diesel fuel is injected directly into the cylinder. The results suggest that the reduction in NOx can be directly correlated with the intake dilution caused by EGR and the correlation is largely independent of the fuelling strategy, the intake boost, and the engine load level. Simultaneously ultra-low NOx and smoke emissions can be achieved at high intake boost and intake dilution levels in the diesel-only combustion strategy and at high ethanol fractions in the dual-fuel strategy. The efficiency penalty associated with EGR is attributed to two primary factors; the combustion off-phasing and the reduction in combustion efficiency. The combustion off-phasing can be minimized by the closed loop control of the diesel injection timing in both the fuelling strategies, whereas the combustion efficiency can be improved by limiting the intake dilution to moderate levels. The

Experimental investigations of combustion and emission characteristics of rapeseed oil–diesel blends in a two cylinder agricultural diesel engine

International Nuclear Information System (INIS)

Qi, D.H.; Lee, C.F.; Jia, C.C.; Wang, P.P.; Wu, S.T.

2014-01-01

Highlights: • The main properties of rapeseed oil and diesel fuel were measure and analyzed. • The cylinder pressure of the rapeseed oil–diesel blends was measured and compared. • The heat release rate of the test fuels was calculated and the combustion process was analyzed. • The fuel consumption and emissions characteristics were measured and compared. - Abstract: The main objective of this paper was to study the performance, emissions and combustion characteristics of a diesel engine using rapeseed oil–diesel blends. The main fuel properties of rapeseed oil (RSO) were investigated and compared with that of diesel fuel. The experimental results showed that the viscosity and density of the blends were decreased and approached to that of diesel fuel when RSO volume fraction was less than 20%. At low engine loads, the start of combustion for the blends was almost similar to that for diesel fuel, but the peak cylinder pressure and heat release rate were higher. At high engine loads, the start of combustion for the blends was slightly earlier than that for diesel fuel, but the peak cylinder pressure and heat release rate were identical. For the blends, there was slightly higher brake specific fuel consumptions (BSFC) and brake specific energy consumptions (BSEC) at low engine loads. Smoke emission was higher at low engine loads, but lower at high engine loads. Nitrogen oxide (NO x ) emission was observed slightly lower at low engine loads and almost identical at high engine loads. Carbon monoxide (CO) and hydrocarbon (HC) emission were higher under all range of engine loads for the blends

Effects of biobutanol and biobutanol–diesel blends on combustion and emission characteristics in a passenger car diesel engine with pilot injection strategies

International Nuclear Information System (INIS)

Yun, Hyuntae; Choi, Kibong; Lee, Chang Sik

2016-01-01

Highlights: • Effects of biobutanol blends on NOx and soot emission characteristics in a diesel engine. • Comparison of combustion characteristics between biobutanol and diesel fuels. • Effect of pilot injection on combustion and emissions reduction in a diesel engine. - Abstract: In this study, we investigated the effect of biobutanol and biobutanol–diesel blends on the combustion and emission characteristics in a four-cylinder compression ignition engine using pilot injection strategies. The test fuels were a mixture of 10% biobutanol and 90% conventional diesel (Bu10), 20% biobutanol and 80% diesel (Bu20), and 100% diesel fuel (Bu0) based on mass. To study the combustion and emission characteristics of the biobutanol blended fuels, we carried out experimental investigations under various pilot injection timings from BTDC 20° to BTDC 60° with constant main injection timing. As the butanol content in the blended fuel increased, the experimental results indicated that the ignition delay was longer than that of diesel fuel for all pilot injection timings. Also, the indicated specific fuel consumption (ISFC) of the blended fuels was higher than that of diesel at all test conditions. However, the exhaust temperature was lower than that of diesel at all injection timings. Nitrogen oxide (NOx), carbon monoxide (CO) and soot from Bu20 were lower than those from diesel fuel at all test conditions and hydrocarbons (HC) were higher than that from diesel.

Combustion of jojoba methyl ester in an indirect injection diesel engine

Energy Technology Data Exchange (ETDEWEB)

Selim, M.Y.E. [United Arab Emirates University, Al-Ain (United Arab Emirates). Mechanical Engineering Dept.; Radwan, M.S.; Elfeky, S.M.S. [Helwan University, Cairo (Egypt). Mechanical Power Engineering Dept.

2003-07-01

An experimental investigation has been carried out to examine for the first time the performance and combustion noise of an indirect injection diesel engine running with new fuel derived from pure jojoba oil, jojoba methyl ester, and its blends with gas oil. A Ricardo E6 compression swirl diesel engine was fully instrumented for the measurement of combustion pressure and its rise rate and other operating parameters. Test parameters included the percentage of jojoba methyl ester in the blend, engine speed, load, injection timing and engine compression ratio. Results showed that the new fuel derived from jojoba is generally comparable and a good replacement to gas oil in diesel engine at most engine operating conditions, in terms of performance parameters and combustion noise produced. (author)

Effect of two-stage injection on combustion and emissions under high EGR rate on a diesel engine by fueling blends of diesel/gasoline, diesel/n-butanol, diesel/gasoline/n-butanol and pure diesel

International Nuclear Information System (INIS)

Zheng, Zunqing; Yue, Lang; Liu, Haifeng; Zhu, Yuxuan; Zhong, Xiaofan; Yao, Mingfa

2015-01-01

Highlights: • Two-stage injection using diesel blended fuel at high EGR (46%) was studied. • Blending fuels induce retarded pilot heat release and have less effect on MPRR. • Effects of injection parameters of blended fuels on emissions are similar to diesel. • Different fuels have little influence on post combustion heat release. • Small quantity post injection close to main results in better efficiency and emissions. - Abstract: The effect of two-stage injection on combustion and emission characteristics under high EGR (46%) condition were experimentally investigated. Four different fuels including pure diesel and blended fuels of diesel/gasoline, diesel/n-butanol, diesel/gasoline/n-butanol were tested. Results show that blending gasoline or/and n-butanol in diesel improves smoke emissions while induces increase in maximum pressure rise rate (MPRR). Adopting pilot injection close to main injection can effectively reduce the peak of premixed heat release rate and MPRR. However, for fuels blends with high percentage of low cetane number fuel, the effect of pilot fuel on ignition can be neglected and the improvement of MPRR is not that obvious. Pilot-main interval presents more obvious effect on smoke than pilot injection rate does, and the smoke emissions decrease with increasing pilot-main interval. A longer main-post interval results in a lower post heat release rate and prolonged combustion duration. While post injection rate has little effect on the start of ignition for post injection. The variation in fuel properties caused by blending gasoline or/and n-butanol into diesel does not impose obvious influence on post combustion. The smoke emission increases first and then declines with retard of post injection timing. Compared to diesel, the smoke emissions of blended fuels are more sensitive to the variation of post injection strategy

Investigation on combustion parameters of palm biodiesel operating with a diesel engine

Directory of Open Access Journals (Sweden)

M.H.M. Yasin

2015-12-01

Full Text Available Biodiesel is a renewable and decomposable fuel which is derived from edible and non-edible oils. It has different properties compared to conventional diesel but can be used directly in diesel engines. Different fuel properties characterise different combustion-phasing parameters such as cyclic variations of Indicated Mean Effective Pressure (IMEP and maximum pressure (Pmax. In this study, cyclic variations of combustion parameters such as IMEP and Pmax were investigated using a multi-cylinder diesel engine operating with conventional diesel and palm biodiesel. The experiments were conducted using different engine loads; 20, 40, and 60% at a constant engine speed of 2500 rpm. The coefficient of variation (COV and standard deviation of parameters were used to evaluate the cyclic variations of the combustion phasing parameters for the test fuels at specific engine test conditions. It was observed that palm biodiesel has lower COV IMEP compared to conventional diesel but is higher in COV Pmax at higher engine loads respectively. In addition, palm biodiesel tends to have a higher recurrence for the frequency distribution for maximum pressure. It can be concluded from the study that the fuel properties of palm biodiesel have influenced most of the combustion parameters.

Biomass utilization for green environment: Co-combustion of diesel fuel and producer gas in thermal application

International Nuclear Information System (INIS)

Hussain, A.; Ani, F.N.; Mehamed, A.F.

2007-01-01

Study of co-combustion of diesel oil and producer gas from a gasifier, individually as well as combined, in an experimental combustion chamber revealed that the producer gas can be co-combusted with liquid fuel. The process produced more CO, NO/sub x/, SO/sub 2/ and CO/sub 2/ as compared to the combustion of diesel oil alone; the exhaust temperature for the process was higher than the diesel combustion alone. (author)

Combustion performance, flame, and soot characteristics of gasoline–diesel pre-blended fuel in an optical compression-ignition engine

International Nuclear Information System (INIS)

Jeon, Joonho; Lee, Jong Tae; Kwon, Sang Il; Park, Sungwook

2016-01-01

Highlights: • Gasoline–diesel pre-blended fuel was investigated in an optical direct-injection diesel engine. • KIVA3V-CHEMKIN code modeled blended fuel spray and combustion with discrete multi-component model. • Flame and soot characteristics in the combustion chamber were shown by optical kits. • Combustion performance and soot emissions for gasoline–diesel blended fuel were discussed. - Abstract: Among the new combustion technologies available for internal combustion engines to enhance performance and reduce exhausted emissions, the homogeneous charge compression ignition method is one of the most effective strategies for the compression-ignition engine. There are some challenges to realize the homogeneous charge compression ignition method in the compression-ignition engine. The use of gasoline–diesel blended fuel has been suggested as an alternative strategy to take advantages of homogeneous charge compression ignition while overcoming its challenges. Gasoline and diesel fuels are reference fuels for the spark-ignition and compression-ignition engines, respectively, both of which are widely used. The application of both these fuels together in the compression-ignition engine has been investigated using a hybrid injection system combining port fuel injection (gasoline) and direct injection (diesel); this strategy is termed reactivity controlled compression ignition. However, the pre-blending of gasoline and diesel fuels for direct injection systems has been rarely studied. For the case of direct injection of pre-blended fuel into the cylinder, various aspects of blended fuels should be investigated, including their spray breakup, fuel/air mixing, combustion development, and emissions. In the present study, the use of gasoline–diesel pre-blended fuel in an optical single-cylinder compression-ignition engine was investigated under various conditions of injection timing and pressure. Furthermore, KIVA-3V release 2 code was employed to model the

Spray combustion of Jet-A and diesel fuels in a constant volume combustion chamber

International Nuclear Information System (INIS)

Jing, Wei; Roberts, William L.; Fang, Tiegang

2015-01-01

This work investigates the spray combustion of Jet-A fuel in an optical constant-volume combustion chamber under different ambient initial conditions. Ambient temperature was varied at 800 K, 1000 K, and 1200 K and five different ambient O 2 concentrations were used, spanning 10–21%. These ambient conditions can be used to mimic practical diesel engine working conditions under different fuel injection timings and exhaust gas recirculation (EGR) levels. Both transient and quasi-steady state analyses were conducted. The transient analysis focused on the flame development from the beginning to the end of the combustion process, illustrating how the flame structure evolves with time. The quasi-steady state analysis concentrated on the stable flame structure and compared the flame emissions in terms of spatially integrated intensity, flame effective area, and intensity per pixel. The transient analysis was based on measurements using high-speed imaging of both OH ∗ chemiluminescence and broadband natural luminosity (NL). For the quasi-steady state analysis, three flame narrow-band emissions (OH ∗ at 310 nm, Band A at 430 nm and Band B at 470 nm) were captured using an ICCD camera. Based on the current Jet-A data and diesel data obtained from previous experiments, a comparison between Jet-A and diesel was made in terms of flame development during the transient state and spatially integrated intensity, flame effective area, and intensity per pixel during the quasi-steady state. For the transient results, Jet-A shares a similar flame development trend to diesel, but featuring a narrower region of NL and a wider region of OH ∗ with the increase of ambient temperature and O 2 concentration. The soot cloud is oxidized more quickly for Jet-A than diesel at the end of combustion, evident by comparing the area of NL, especially under high O 2 concentration. The quasi-steady state results suggest that soot is oxidized effectively under high O 2 concentration conditions by

FORMALIZATION OF DIESEL ENGINE OPERATION CONSIDERING THE EVALUATION OF VELOCITY DURING THE COMBUSTION PROCESSES

Directory of Open Access Journals (Sweden)

V. P. Litvinenko

2015-10-01

Full Text Available Purpose. Under modern conditions the applying methods and design models as well as the evaluation of the operational characteristics of diesel engines do not completely take into consideration the specifics of the combustion processes. In part, such situation is characterized by the complexity of considering of varied by its nature processes that haven’t been completely investigated. In this context it is necessary to find the new methods and models which would provide relatively simple solutions through the use of integrated factors based on the analysis of parameters of diesel engines. Methodology. The proposed algorithms for the estimating of the combustion process in the form of volumetric and linear velocities is based on the well-known parameters of power and mean effective pressure and allows to compare the efficiency of their behavior in various versions of diesel engines. Findings. The author specified that the volumetric / linear velocity ratio is characterized by some strength and depends on the geometric dimensions of the cylinder-piston group. Due to the assumptions it has become possible to consider the operation of a diesel engine as a system comprising: 1 the subsystem that provides the possibility of obtaining the thermal energy; 2 the subsystem providing the thermal energy transformation; 3 the subsystem that provides the necessary diesel engine power depending on terms of combustion of air-fuel mixture. Originality. The author of the paper proposed the indices of volumetric and linear combustion velocity of air-fuel mixture in the engine cylinder, that allow to obtain the comparative value in different modifications taking into account the possible choice of optimum ratio. Practical value. The usage of indices of volumetric and linear velocities of the combustion processes in the engine cylinder combined with a mathematical model will simplify the method of diesels calculating. Parametric indices of the mentioned velocities

Development and validation of spray models for investigating diesel engine combustion and emissions

Science.gov (United States)

Som, Sibendu

Diesel engines intrinsically generate NOx and particulate matter which need to be reduced significantly in order to comply with the increasingly stringent regulations worldwide. This motivates the diesel engine manufacturers to gain fundamental understanding of the spray and combustion processes so as to optimize these processes and reduce engine emissions. Strategies being investigated to reduce engine's raw emissions include advancements in fuel injection systems, efficient nozzle orifice design, injection and combustion control strategies, exhaust gas recirculation, use of alternative fuels such as biodiesel etc. This thesis explores several of these approaches (such as nozzle orifice design, injection control strategy, and biodiesel use) by performing computer modeling of diesel engine processes. Fuel atomization characteristics are known to have a significant effect on the combustion and emission processes in diesel engines. Primary fuel atomization is induced by aerodynamics in the near nozzle region as well as cavitation and turbulence from the injector nozzle. The breakup models that are currently used in diesel engine simulations generally consider aerodynamically induced breakup using the Kelvin-Helmholtz (KH) instability model, but do not account for inner nozzle flow effects. An improved primary breakup (KH-ACT) model incorporating cavitation and turbulence effects along with aerodynamically induced breakup is developed and incorporated in the computational fluid dynamics code CONVERGE. The spray simulations using KH-ACT model are "quasi-dynamically" coupled with inner nozzle flow (using FLUENT) computations. This presents a novel tool to capture the influence of inner nozzle flow effects such as cavitation and turbulence on spray, combustion, and emission processes. Extensive validation is performed against the non-evaporating spray data from Argonne National Laboratory. Performance of the KH and KH-ACT models is compared against the evaporating and

Experimental setup for combustion characteristics in a diesel engine using derivative fuel from biomass

International Nuclear Information System (INIS)

Andi Mulkan; Zainal, Z.A.

2006-01-01

Reciprocating engines are normally run on petroleum fuels or diesel fuels. Unfortunately, energy reserves such as gas and oil are decreasing. Today, with renewable energy technologies petroleum or diesel can be reduced and substituted fully or partly by alternative fuels in engine. The objective of this paper is to setup the experimental rig using producer gas from gasification system mix with diesel fuel and fed to a diesel engine. The Yanmar L60AE-DTM single cylinder diesel engine is used in the experiment. A 20 kW downdraft gasifier has been developed to produce gas using cut of furniture wood used as biomass source. Air inlet of the engine has been modified to include the producer gas. An AVL quartz Pressure Transducer P4420 was installed into the engine head to measure pressure inside the cylinder of the engine. Several test were carried out on the downdraft gasifier system and diesel engine. The heating value of the producer gas is about 4 MJ/m 3 and the specific biomass fuel consumption is about 1.5 kg/kWh. Waste cooking oil (WCO) and crude palm oil (CPO) were used as biomass fuel. The pressure versus crank angle diagram for using blend of diesel are presented and compared with using diesel alone. The result shows that the peak pressure is higher. The premixed combustion is lower but have higher mixing controlled combustion. The CO and NO x emission are higher for biomass fuel

Optimization of combustion chamber geometry and operating conditions for compression ignition engine fueled with pre-blended gasoline-diesel fuel

International Nuclear Information System (INIS)

Lee, Seokhwon; Jeon, Joonho; Park, Sungwook

2016-01-01

Highlights: • Pre-blended gasoline-diesel fuel was used with direct injection system. • KIVA-CHEMKIN code modeled dual-fuel fuel spray and combustion processes with discrete multi-component model. • The characteristics of Combustion and emission on pre-blended fuel was investigated with various fuel reactivities. • Optimization of combustion chamber shape improved combustion performance of the gasoline-diesel blended fuel engine. - Abstract: In this study, experiments and numerical simulations were used to improve the fuel efficiency of compression ignition engine using a gasoline-diesel blended fuel and an optimization technology. The blended fuel is directly injected into the cylinder with various blending ratios. Combustion and emission characteristics were investigated to explore the effects of gasoline ratio on fuel blend. The present study showed that the advantages of gasoline-diesel blended fuel, high thermal efficiency and low emission, were maximized using the numerical optimization method. The ignition delay and maximum pressure rise rate increased with the proportion of gasoline. As the gasoline fraction increased, the combustion duration and the indicated mean effective pressure decreased. The homogeneity of the fuel-air mixture was improved due to longer ignition delay. Soot emission was significantly reduced up to 90% compared to that of conventional diesel. The nitrogen oxides emissions of the blended fuel increased slightly when the start of injection was retarded toward top dead center. For the numerical study, KIVA-CHEMKIN multi-dimensional CFD code was used to model the combustion and emission characteristics of gasoline-diesel blended fuel. The micro genetic algorithm coupled with the KIVA-CHEMKIN code were used to optimize the combustion chamber shape and operating conditions to improve the combustion performance of the blended fuel engine. The optimized chamber geometry enhanced the fuel efficiency, for a level of nitrogen oxides

Combustion characteristics of a charcoal slurry in a direct injection diesel engine and the impact on the injection system performance

International Nuclear Information System (INIS)

Soloiu, Valentin; Lewis, Jeffery; Yoshihara, Yoshinobu; Nishiwaki, Kazuie

2011-01-01

The paper presents the research results pertaining to the renewable biomass charcoal-diesel slurries and their use as alternative fuels for combustion in diesel generating plants. The utilization of charcoal slurry fuel aims to reduce diesel oil consumption and would decrease fossil green house emissions into the atmosphere. The paper investigates the formulation, emulsification, sprays, combustion, injection system operation, and subsequent wear with charcoal-diesel slurries. In the research, cedar wood chips were used for the production of charcoal to be emulsified with diesel oil. The slurry's viscosity of 27 cP achieved the target ( o C. Charcoal slurry displayed a high vaporization rate of 75% by wt. at 300 o C. Engine investigations showed that the top combustion pressure at 1200 rpm and 100% load (7.8 brake mean effective pressure (bmep)) was 79 bar for diesel fuel and 78 bar for the charcoal slurry fuel. From the injection and heat release history was found an ignition delay of 1.7 ms for diesel that increased to 2.1 ms for the slurry fuel. A higher net heat release for charcoal slurry was observed, up to 180 J/crank angle degrees (CAD) compared with the diesel at 145 J/CAD The maximum combustion temperature reached 2300 K for diesel and 2330 K for slurry. The heat fluxes for both fuels have similar values and trends during the entire cycle showing the good compatibility of charcoal slurry with a diesel type combustion and low soot radiation. The exhaust temperatures were about 40-50 o C higher for charcoal slurry at 19 o before top dead center (BTDC) injection timing. The engine's bsfc increased as expected due to the lower heating value of the slurry fuel. The smoke Bosch no. was lower for the slurry fuel at any load, and is believed that the oxygen from the charcoal had a beneficial effect. The measured emissions of slurry fuel were better at 13 o BTDC than those of diesel fuel with the original engine settings and the remaining 6-10% oxygen content in

Understanding Combustion and Soot Formation in Diesel Engines

Science.gov (United States)

2016-09-09

distributions of PLII signals help understand the soot distributions within diesel/ biodiesel flames. In addition, planar laser-induced Figure 1. Transported ...Prescribed by ANSI Std. Z39.18 Page 1 of 1FORM SF 298 9/14/2016https://livelink.ebs.afrl.af.mil/livelink/llisapi.dll This project investigated biodiesel ...emissions testing. 1 FINAL REPORT Project title: Understanding combustion and soot formation in biodiesel fuelled diesel engines Lead Institute and

An Experimental Investigation on the Combustion and Heat Release Characteristics of an Opposed-Piston Folded-Cranktrain Diesel Engine

Directory of Open Access Journals (Sweden)

Fukang Ma

2015-06-01

Full Text Available In opposed-piston folded-cranktrain diesel engines, the relative movement rules of opposed-pistons, combustion chamber components and injector position are different from those of conventional diesel engines. The combustion and heat release characteristics of an opposed-piston folded-cranktrain diesel engine under different operating conditions were investigated. Four phases: ignition delay, premixed combustion, diffusion combustion and after combustion are used to describe the heat release process of the engine. Load changing has a small effect on premixed combustion duration while it influences diffusion combustion duration significantly. The heat release process has more significant isochoric and isobaric combustion which differs from the conventional diesel engine situation, except at high exhaust pressure and temperature, due to its two-stroke and uniflow scavenging characteristics. Meanwhile, a relatively high-quality exhaust heat energy is produced in opposed-piston folded-cranktrain diesel engines.

Combustion aided by a glow plug in diesel engines under cold idling conditions

OpenAIRE

Li, Qile

2016-01-01

Glow plugs are widely used to promote the desired cold start and post-cold start combustion characteristics of light duty diesel engines. The importance of the glow plug becomes more apparent when the compression ratio is low. An experimental investigation of combustion initiation and development aided by the glow plug has been carried out on a single cylinder HPCR DI diesel engine with a low compression ratio of 15.5:1. High speed imaging of combustion initiated by the glow plug in a combust...

Effect of laser induced plasma ignition timing and location on Diesel spray combustion

International Nuclear Information System (INIS)

Pastor, José V.; García-Oliver, José M.; García, Antonio; Pinotti, Mattia

2017-01-01

Highlights: • Laser plasma ignition is applied to a direct injection Diesel spray, compared with auto-ignition. • Critical local fuel/air ratio for LIP provoked ignition is obtained. • The LIP system is able to stabilize Diesel combustion compared to auto-ignition cases. • Varying LIP position along spray axis directly affects Ignition-delay. • Premixed combustion is reduced both by varying position and delay of the LIP ignition system. - Abstract: An experimental study about the influence of the local conditions at the ignition location on combustion development of a direct injection spray is carried out in an optical engine. A laser induced plasma ignition system has been used to force the spray ignition, allowing comparison of combustion’s evolution and stability with the case of conventional autoignition on the Diesel fuel in terms of ignition delay, rate of heat release, spray penetration and soot location evolution. The local equivalence ratio variation along the spray axis during the injection process was determined with a 1D spray model, previously calibrated and validated. Upper equivalence ratios limits for the ignition event of a direct injected Diesel spray, both in terms of ignition success possibilities and stability of the phenomena, could been determined thanks to application of the laser plasma ignition system. In all laser plasma induced ignition cases, heat release was found to be higher than for the autoignition reference cases, and it was found to be linked to a decrease of ignition delay, with the premixed peak in the rate of heat release curve progressively disappearing as the ignition delay time gets shorter. Ignition delay has been analyzed as a function of the laser position, too. It was found that ignition delay increases for plasma positions closer to the nozzle, indicating that the amount of energy introduced by the laser induced plasma is not the only parameter affecting combustion initiation, but local equivalence ratio

Effect of hydrogen-diesel combustion on the performance and combustion parameters of a dual fuelled diesel engine

Energy Technology Data Exchange (ETDEWEB)

Bose, P.K.; Banerjee, Rahul; Deb, Madhujit [Mechanical Engineering Department, National Institute of Technology, Agartala, Tripura-799055 (India)

2013-07-01

Petroleum crude is expected to remain main source of transport fuels at least for the next 20 to 30 years. The petroleum crude reserves however, are declining and consumption of transport fuels particularly in the developing countries is increasing at high rates. Severe shortage of liquid fuels derived from petroleum may be faced in the second half of this century. In this paper, experiments are performed in a fur stroke, single cylinder, compression ignition diesel engine with dual fuel mode. Diesel and hydrogen are used as pilot liquid and primary gaseous fuel, respectively. The objective of this study is to find out the effects on combustion and performance parameters observed at diesel hydrogen fuel mixture for all the different loadings (2kg,4kg,6kg,8kg,10kg and 12kg) in the engine.

Towards Control-Oriented Modeling of Natural Gas-Diesel RCCI Combustion

NARCIS (Netherlands)

Bekdemir, C.; Baert, R.; Willems, F.; Somers, B.

2015-01-01

For natural gas (NG)-diesel RCCI, a multi-zonal, detailed chemistry modeling approach is presented. This dual fuel combustion process requires further understanding of the ignition and combustion processes to maximize thermal efficiency and minimize (partially) unburned fuel emissions. The

Towards control-oriented modeling of natural gas-diesel RCCI combustion

NARCIS (Netherlands)

Bekdemir, C.; Baert, R.S.G.; Willems, F.P.T.; Somers, L.M.T.

2015-01-01

For natural gas (NG)-diesel RCCI, a multi-zonal, detailed chemistry modeling approach is presented. This dual fuel combustion process requires further understanding of the ignition and combustion processes to maximize thermal efficiency and minimize (partially) unburned fuel emissions. The

Application of macro-cellular SiC reactor to diesel engine-like injection and combustion conditions

Science.gov (United States)

Cypris, Weclas, M.; Greil, P.; Schlier, L. M.; Travitzky, N.; Zhang, W.

2012-05-01

One of novel combustion technologies for low emissions and highly efficient internal combustion engines is combustion in porous reactors (PM). The heat release process inside combustion reactor is homogeneous and flameless resulting in a nearly zero emissions level. Such combustion process, however is non-stationary, is performed under high pressure with requirement of mixture formation directly inside the combustion reactor (high pressure fuel injection). Reactor heat capacity resulting in lowering of combustion temperature as well as internal heat recuperation during the engine cycle changes the thermodynamic conditions of the process as compared to conventional engine. For the present investigations a macro-cellular lattice structure based on silicon carbide (non-foam structure) with 600 vertical cylindrical struts was fabricated and applied to engine-like combustion conditions (combustion chamber). The lattice design with a high porosity > 80% was shaped by indirect three-dimensional printing of a SiC powder mixed with a dextrin binder which also serves as a carbon precursor. In order to perform detailed investigations on low-and high-temperature oxidation processes in porous reactors under engine-like conditions, a special combustion chamber has been built and equipped with a Diesel common-rail injection system. This system simulates the thermodynamic conditions at the time instance of injection onset (corresponding to the nearly TDC of compression in a real engine). Overall analysis of oxidation processes (for variable initial pressure, temperature and air excess ratio) for free Diesel spray combustion and for combustion in porous reactor allows selection of three regions representing different characteristics of the oxidation process represented by a single-step and multi-step reactions Another characteristic feature of investigated processes is reaction delay time. There are five characteristic regions to be selected according to the delay time (t) duration

Spray-combustion process characterization in a common rail diesel engine fuelled with butanol-diesel blends by conventional methods and optical diagnostics

Directory of Open Access Journals (Sweden)

Simona Silvia Merola

2014-04-01

Full Text Available The target of a sustainable mobility has led to investigate advanced combustion modes and fuels technologies. On the other side, the increasing global energy demand and the decreasing fossil-energy resources are enhancing the interest in the use of renewable alternative fuels for compression ignition engines with the target of near-zero emission levels. Although performance and emissions of alternative-fuel within light-duty diesel engines have been extensively investigated, results of fuel chemical composition impact on combustion by integrated optical methodologies are lacking. In order to meet this challenge, one of the main objectives of the research efforts is to characterize the combustion and species evolution. In this investigation, conventional tests and optical diagnostics were employed to enhance the comprehension of the combustion process and chemical markers in a common rail compression ignition engine powered by butanol-diesel blends. The investigation was focused on the effect of the injection strategy and blend composition on in-cylinder spray combustion and soot formation, through UV-visible digital imaging and natural emission spectroscopy. Experiments were performed in an optically accessible single cylinder high swirl compression ignition engine, equipped with a common rail multi-jets injection system. UV-visible emission spectroscopy was used to follow the evolution of the combustion process chemical markers. Spectral features of OH were identified and followed during the spray combustion process examining different pilot-main dwell timings. Soot spectral evidence in the visible wavelength range was correlated to soot engine out emissions. In this work, conventional and optical data related to diesel fuel blended with 40 % of n-butanol will be presented.

Effects of Fuel Quantity on Soot Formation Process for Biomass-Based Renewable Diesel Fuel Combustion

KAUST Repository

Jing, Wei; Wu, Zengyang; Roberts, William L.; Fang, Tiegang

2016-01-01

Soot formation process was investigated for biomass-based renewable diesel fuel, such as biomass to liquid (BTL), and conventional diesel combustion under varied fuel quantities injected into a constant volume combustion chamber. Soot measurement

Spray combustion of biomass-based renewable diesel fuel using multiple injection strategy in a constant volume combustion chamber

KAUST Repository

Jing, Wei

2016-05-26

Effect of a two-injection strategy associated with a pilot injection on the spray combustion process was investigated under conventional diesel combustion conditions (1000 K and 21% O2 concentration) for a biomass-based renewable diesel fuel, i.e., biomass to liquid (BTL), and a regular No. 2 diesel in a constant volume combustion chamber using multiband flame measurement and two-color pyrometry. The spray combustion flame structure was visualized by using multiband flame measurement to show features of soot formation, high temperature and low temperature reactions, which can be characterized by the narrow-band emissions of radicals or intermediate species such as OH, HCHO, and CH. The objective of this study was to identify the details of multiple injection combustion, including a pilot and a main injection, and to provide further insights on how the two injections interact. For comparison, three injection strategies were considered for both fuels including a two-injection strategy (Case TI), single injection strategy A (Case SA), and single injection strategy B (Case SB). Multiband flame results show a strong interaction, indicated by OH emissions between the pilot injection and the main injection for Case TI while very weak connection is found for the narrow-band emissions acquired through filters with centerlines of 430 nm and 470 nm. A faster flame development is found for the main injection of Case TI compared to Cases SA and SB, which could be due to the high temperature environment and large air entrainment from the pilot injection. A lower soot level is observed for the BTL flame compared to the diesel flame for all three injection types. Case TI has a lower soot level compared to Cases SA and SB for the BTL fuel, while the diesel fuel maintains a similar soot level among all three injection strategies. Soot temperature of Case TI is lower for both fuels, especially for diesel. Based on these results, it is expected that the two-injection strategy could be

FUEL FORMULATION EFFECTS ON DIESEL FUEL INJECTION, COMBUSTION, EMISSIONS AND EMISSION CONTROL

Energy Technology Data Exchange (ETDEWEB)

Boehman, A; Alam, M; Song, J; Acharya, R; Szybist, J; Zello, V; Miller, K

2003-08-24

This paper describes work under a U.S. DOE sponsored Ultra Clean Fuels project entitled ''Ultra Clean Fuels from Natural Gas,'' Cooperative Agreement No. DE-FC26-01NT41098. In this study we have examined the incremental benefits of moving from low sulfur diesel fuel and ultra low sulfur diesel fuel to an ultra clean fuel, Fischer-Tropsch diesel fuel produced from natural gas. Blending with biodiesel, B100, was also considered. The impact of fuel formulation on fuel injection timing, bulk modulus of compressibility, in-cylinder combustion processes, gaseous and particulate emissions, DPF regeneration temperature and urea-SCR NOx control has been examined. The primary test engine is a 5.9L Cummins ISB, which has been instrumented for in-cylinder combustion analysis and in-cylinder visualization with an engine videoscope. A single-cylinder engine has also been used to examine in detail the impacts of fuel formulation on injection timing in a pump-line-nozzle fueling system, to assist in the interpretation of results from the ISB engine.

Characterising Combustion in Diesel Engines : Using parameterised finite stage cylinder process models

NARCIS (Netherlands)

Ding, Y.

2011-01-01

Characterising combustion of diesel engines is not only necessary when researching the instantaneous combustion phenomena but also when investigating the change of the combustion process under variable engine operating conditions. An effective way to achieve this goal is to parameterize the

Effects of pilot injection pressure on the combustion and emissions characteristics in a diesel engine using biodiesel–CNG dual fuel

International Nuclear Information System (INIS)

Ryu, Kyunghyun

2013-01-01

Highlights: • Injection pressure of pilot fuel in dual fuel combustion (DFC) affects the engine power and exhaust emissions. • In the biodiesel–CNG DFC mode, the combustion begins and ends earlier as the pilot-fuel injection pressure increases. • The ignition delay in the DFC mode is about 1.2–2.6 °CA longer than that in the diesel single fuel combustion (SFC) mode. • The smoke and NOx emissions are significantly reduced in the DFC mode. - Abstract: Biodiesel–compressed natural gas (CNG) dual fuel combustion (DFC) system is studied for the simultaneous reduction of particulate matters (PM) and nitrogen oxides (NOx) from diesel engine. In this study, biodiesel is used as a pilot injection fuel to ignite the main fuel, CNG of DFC system. In particular, the pilot injection pressure is controlled to investigate the characteristics of engine performance and exhaust emissions in a single cylinder diesel engine. The results show that the indicated mean effective pressure (IMEP) of biodiesel–CNG DFC mode is lower than that of diesel single fuel combustion (SFC) mode at higher injection pressure. However, the combustion stability of biodiesel–CNG DFC mode is increased with the increase of pilot injection pressure. At the same injection pressure, the start of combustion of biodiesel–CNG DFC is delayed compared to diesel SFC due to the increase of ignition delay of pilot fuel. On the contrary, it is observed that as the pilot injection pressure increase, the combustion process begins and ends a little earlier for biodiesel–CNG DFC. The ignition delay in the DFC is about 1.2–2.6 °CA longer compared to diesel SFC, but decreases with increases of pilot injection pressure. Smoke and NOx emissions are decreased and increased, respectively, as the pilot injection pressure increases in the biodiesel–CNG DFC. In comparison to diesel SFC, smoke emissions are significantly reduced over all the operating conditions and NOx emissions also exhibited similar

An experimental investigation of the combustion process of a heavy-duty diesel engine enriched with H{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Liew, C.; Li, H.; Nuszkowski, J.; Liu, S.; Gatts, T.; Atkinson, R.; Clark, N. [Department of Mechanical and Aerospace Engineering, West Virginia University, Morgantown, WV 26506-6106 (United States)

2010-10-15

This paper investigated the effect of hydrogen (H{sub 2}) addition on the combustion process of a heavy-duty diesel engine. The addition of a small amount of H{sub 2} was shown to have a mild effect on the cylinder pressure and combustion process. When operated at high load, the addition of a relatively large amount of H{sub 2} substantially increased the peak cylinder pressure and the peak heat release rate. Compared to the two-stage combustion process of diesel engines, a featured three-stage combustion process of the H{sub 2}-diesel dual fuel engine was observed. The extremely high peak heat release rate represented a combination of diesel diffusion combustion and the premixed combustion of H{sub 2} consumed by multiple turbulent flames, which substantially enhanced the combustion process of H{sub 2}-diesel dual fuel engine. However, the addition of a relatively large amount of H{sub 2} at low load did not change the two-stage heat release process pattern. The premixed combustion was dramatically inhibited while the diffusion combustion was slightly enhanced and elongated. The substantially reduced peak cylinder pressure at low load was due to the deteriorated premixed combustion. (author)

Combustion Model and Control Parameter Optimization Methods for Single Cylinder Diesel Engine

Directory of Open Access Journals (Sweden)

Bambang Wahono

2014-01-01

Full Text Available This research presents a method to construct a combustion model and a method to optimize some control parameters of diesel engine in order to develop a model-based control system. The construction purpose of the model is to appropriately manage some control parameters to obtain the values of fuel consumption and emission as the engine output objectives. Stepwise method considering multicollinearity was applied to construct combustion model with the polynomial model. Using the experimental data of a single cylinder diesel engine, the model of power, BSFC, NOx, and soot on multiple injection diesel engines was built. The proposed method succesfully developed the model that describes control parameters in relation to the engine outputs. Although many control devices can be mounted to diesel engine, optimization technique is required to utilize this method in finding optimal engine operating conditions efficiently beside the existing development of individual emission control methods. Particle swarm optimization (PSO was used to calculate control parameters to optimize fuel consumption and emission based on the model. The proposed method is able to calculate control parameters efficiently to optimize evaluation item based on the model. Finally, the model which added PSO then was compiled in a microcontroller.

Research on EHN additive on the diesel engine combustion characteristics in plateau environment

Science.gov (United States)

Sun, Zhixin; Li, Ruoting; Wang, Xiancheng; Hu, Chuan

2017-03-01

Aiming at the combustion deterioration problem of diesel engine in plateau environment, a bench test was carried out for the effects of EHN additive on combustion characteristics of the diesel engine with intake pressure of 0.68 kPa. Test results showed that with the full load working condition of 1 400 r/min: Cylinder pressure and pressure uprising rate decreased with EHN additive added in, mechanical load on the engine could be relieved; peak value of the heat release rate decreased and its occurrence advanced, ignition delay and combustion duration were shortened; cylinder temperature and exhaust gas temperature declined, thermal load on the engine could be relieved, output torque increased while specific oil consumption decreased, and effective thermal efficiency of diesel engine increased.

Diesel Combustion and Emission Using High Boost and High Injection Pressure in a Single Cylinder Engine

Science.gov (United States)

Aoyagi, Yuzo; Kunishima, Eiji; Asaumi, Yasuo; Aihara, Yoshiaki; Odaka, Matsuo; Goto, Yuichi

Heavy-duty diesel engines have adopted numerous technologies for clean emissions and low fuel consumption. Some are direct fuel injection combined with high injection pressure and adequate in-cylinder air motion, turbo-intercooler systems, and strong steel pistons. Using these technologies, diesel engines have achieved an extremely low CO2 emission as a prime mover. However, heavy-duty diesel engines with even lower NOx and PM emission levels are anticipated. This study achieved high-boost and lean diesel combustion using a single cylinder engine that provides good engine performance and clean exhaust emission. The experiment was done under conditions of intake air quantity up to five times that of a naturally aspirated (NA) engine and 200MPa injection pressure. The adopted pressure booster is an external supercharger that can control intake air temperature. In this engine, the maximum cylinder pressure was increased and new technologies were adopted, including a monotherm piston for endurance of Pmax =30MPa. Moreover, every engine part is newly designed. As the boost pressure increases, the rate of heat release resembles the injection rate and becomes sharper. The combustion and brake thermal efficiency are improved. This high boost and lean diesel combustion creates little smoke; ISCO and ISTHC without the ISNOx increase. It also yields good thermal efficiency.

Sensors Based Measurement Techniques of Fuel Injection and Ignition Characteristics of Diesel Sprays in DI Combustion System

Directory of Open Access Journals (Sweden)

S. Rehman

2016-09-01

Full Text Available Innovative sensor based measurement techniques like needle lift sensor, photo (optical sensor and piezoresistive pressure transmitter are introduced and used to measure the injection and combustion characteristics in direct injection combustion system. Present experimental study is carried out in the constant volume combustion chamber to study the ignition, combustion and injection characteristics of the solid cone diesel fuel sprays impinging on the hot surface. Hot surface ignition approach has been used to create variety of advanced combustion systems. In the present study, the hot surface temperatures were varied from 623 K to 723 K. The cylinder air pressures were 20, 30 and 40 bar and fuel injection pressures were 100, 200 and 300 bar. It is found that ignition delay of fuel sprays get reduced with the rise in injection pressure. The ignition characteristics of sprays much less affected at high fuel injection pressures and high surface temperatures. The fuel injection duration reduces with the increase in fuel injection pressures. The rate of heat release becomes high at high injection pressures and it decreases with the increase in injection duration. It is found that duration of burn/combustion decrease with the increase in injection pressure. The use of various sensors is quite effective, reliable and accurate in measuring the various fuel injection and combustion characteristics. The study simulates the effect of fuel injection system parameters on combustion performance in large heavy duty engines.

Effect of the Ethanol Injection Moment During Compression Stroke on the Combustion of Ethanol - Diesel Dual Direct Injection Engine

Science.gov (United States)

Liang, Yu; Zhou, Liying; Huang, Haomin; Xu, Mingfei; Guo, Mei; Chen, Xin

2018-01-01

A set of GDI system is installed on a F188 single-cylinder, air-cooled and direct injection diesel engine, which is used for ethanol injection, with the injection time controlled by the crank angle signal collected by AVL angle encoder. The injection of ethanol amounts to half of the thermal equivalent of an original diesel fuel. A 3D combustion model is established for the ethanol - diesel dual direct injection engine. Diesel was injected from the original fuel injection system, with a fuel supply advance angle of 20°CA. The ethanol was injected into the cylinder during compression process. Diesel injection began after the completion of ethanol injection. Ethanol injection starting point of 240°CA, 260°CA, 280°CA, 300°CA and 319.4°CA were simulated and analyzed. Due to the different timing of ethanol injection, the ignition of the ethanol mixture when diesel fires, results in non-uniform ignition distribution and flame propagation rate, since the distribution and concentration gradients of the ethanol mixture in the cylinder are different, thus affecting the combustion process. The results show that, when ethanol is injected at 319.4°CA, the combustion heat release rate and the pressure rise rate during the initial stage are the highest. Also, the maximum combustion pressure, with a relatively advance phase, is the highest. In case of later initial ethanol injection, the average temperature in the cylinder during the initial combustion period will have a faster rise. In case of initial injection at 319.4°CA, the average temperature in the cylinder is the highest, followed by 240°CA ethanol injection. In the post-combustion stage, the earlier ethanol injection will result in higher average temperature in the cylinder and more complete fuel combustion. The injection of ethanol at 319.4°CA produces earlier and highest NOX emissions.

Computational combustion and emission analysis of hydrogen-diesel blends with experimental verification

International Nuclear Information System (INIS)

Masood, M.; Ishrat, M.M.; Reddy, A.S.

2007-01-01

The paper discusses the effect of blending hydrogen with diesel in different proportions on combustion and emissions. A comparative study was carried out to analyze the effect of direct injection of hydrogen into the combustion chamber with that of induction through the inlet manifold for dual fueling. Percentage of hydrogen substitution varied from 20% to 80%, simultaneously reducing the diesel percentages. CFD analysis of dual fuel combustion and emissions were carried out for both the said methods using the CFD software FLUENT, meshing the combustion chamber was carried out using GAMBIT. The standard combustion and emission models were used in the analysis. In the second part of the paper, the effect of angle of injection in both the methods of hydrogen admission, on performance, combustion and emissions were analyzed. The experimental results were compared with that of simulated values and a good agreement between them was noticed. (author)

Establishment of Combustion Model for Isooctane HCCI Marine Diesel Engine and Research on the Combustion Characteristic

Directory of Open Access Journals (Sweden)

Li Biao

2016-01-01

Full Text Available The homogeneous charge compression ignition (HCCI combustion mode applied in marine diesel engine is expected to be one of alternative technologies to decrease nitrogen oxide (NOX emission and improve energy utilization rate. Applying the chemical-looping combustion (CLC mechanism inside the cylinder, a numerical study on the HCCI combustion process is performed taking a marine diesel engine as application object. The characteristic feature of combustion process is displayed. On this basis, the formation and emission of NOX are analyzed and discussed. The results indicate that the HCCI combustion mode always exhibit two combustion releasing heats: low-temperature reaction and high-temperature reaction. The combustion phase is divided into low-temperature reaction zone, high-temperature reaction zone and negative temperature coefficient (NTC zone. The operating conditions of the high compression ratio, high intake air temperature, low inlet pressure and small excess air coefficient would cause the high in-cylinder pressure which often leads engine detonation. The low compression ratio, low intake air temperature and big excess air coefficient would cause the low combustor temperature which is conducive to reduce NOX emissions. These technological means and operating conditions are expected to meet the NOX emissions limits in MARPOL73/78 Convention-Annex VI Amendment.

Combustion characteristics of compressed natural gas/diesel dual-fuel turbocharged compressed ignition engine

Energy Technology Data Exchange (ETDEWEB)

Shenghua, L.; Longbao, Z.; Ziyan, W.; Jiang, R. [Xi' an Jiaotong Univ. (China). Dept. of Automotive Engineering

2003-09-01

The combustion characteristics of a turbocharged natural gas and diesel dual-fuelled compression ignition (CI) engine are investigated. With the measured cylinder pressures of the engine operated on pure diesel and dual fuel, the ignition delay, effects of pilot diesel and engine load on combustion characteristics are analysed. Emissions of HC, CO, NO{sub x} and smoke are measured and studied too. The results show that the quantity of pilot diesel has important effects on the performance and emissions of a dual-fuel engine at low-load operating conditions. Ignition delay varies with the concentration of natural gas. Smoke is much lower for the developed dual-fuel engine under all the operating conditions. (Author)

Experimental study of combustion noise radiation during transient turbocharged diesel engine operation

International Nuclear Information System (INIS)

Giakoumis, Evangelos G.; Dimaratos, Athanasios M.; Rakopoulos, Constantine D.

2011-01-01

Diesel engine noise radiation has drawn increased attention in recent years since it is associated with the passengers' and pedestrians' discomfort, a fact that has been acknowledged by the manufacturers and the legislation in many countries. In the current study, experimental tests were conducted on a truck, turbocharged diesel engine in order to investigate the mechanism of combustion noise emission under various transient schedules experienced during daily driving conditions, namely acceleration and load increase. To this aim, a fully instrumented test bed was set up in order to capture the development of key engine and turbocharger variables during the transient events. Analytical diagrams are provided to explain the behavior of combustion noise radiation in conjunction with cylinder pressure (spectrum), turbocharger and governor/fuel pump response. Turbocharger lag was found to be the main cause for the noise spikes during all test cases examined, with the engine injection timing calibration and the slow adjustment of cylinder wall temperature to the new fueling conditions playing a vital role. The analysis was extended with a quasi-steady approximation of transient combustion noise using steady-state maps, in order to better highlight the effect of dynamic engine operation on combustion noise emissions. -- Highlights: → Studying the effects of acceleration and load increase on the combustion noise radiation from a turbocharged diesel engine. → Turbocharger lag was the most notable contributor for the behavior of combustion noise radiation. → Turbocharged diesel engine behaves noisier at acceleration compared with the steady-state operation. → Fuel limiter, governing and engine injection timing calibration play a decisive role on the emission of combustion noise. → Transient noise radiation was smoothed the slower the acceleration and the smaller the demanded speed increase.

Development of combustion management concept for natural-aspirated small diesel engine; Shizen kyuki kogata diesel engine no nensho seigyo concept no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Wada, T; Kawano, T; Shoji, M; Kuniyosh, M; Yamashita, O; Nagao, A [Mazda Motor Corp., Tokyo (Japan); Yoshikawa, S [Zexel Corp., Tokyo (Japan)

1997-10-01

We have developed a combustion management concept for natural-aspirated small IDI diesel engines and achieved higher power, lower exhaust emissions and more comfort. The concept is related to improvements of intake volumetric efficiency, EGR effect, mixture formation caused by combustion chamber and spray characteristics, engine management system and after treatment device. This paper describes the concept and experimental results. 3 refs., 14 figs., 1 tab.

Combustion Temperature Effect of Diesel Engine Convert to Compressed Natural Gas Engine

OpenAIRE

Semin; Abdul R. Ismail; Rosli A. Bakar

2009-01-01

Effect of combustion temperature in the engine cylinder of diesel engine convert to Compressed Natural Gas (CNG) engine was presents in this study. The objective of this study was to investigate the engine cylinder combustion temperature effect of diesel engine convert to CNG engine on variation engine speed. Problem statement: The hypothesis was that the lower performance of CNG engine was caused by the effect of lower in engine cylinder temperature. Are the CNG engine is lower cylinder temp...

Combustion, performance and emissions of a diesel power generator fueled with biodiesel-kerosene and biodiesel-kerosene-diesel blends

International Nuclear Information System (INIS)

Bayındır, Hasan; Işık, Mehmet Zerrakki; Argunhan, Zeki; Yücel, Halit Lütfü; Aydın, Hüseyin

2017-01-01

High percentages of biodiesel blends or neat biodiesel cannot be used in diesel engines due to high density and viscosity, and poor atomization properties that lead to some engine operational problems. Biodiesel was produced from canola oil by transesterification process. Test fuels were prepared by blending 80% of the biodiesel with 20% of kerosene (B80&K20) and 80% of the biodiesel with 10% of kerosene and 10% diesel fuel (B80&K10&D10). Fuels were used in a 4 cylinders diesel engine that was loaded with a generator. Combustion, performance and emission characteristics of the blend fuels and D2 in the diesel engine for certain loads of 3.6, 7.2 and 10.8 kW output power and 1500 rpm constant engine speed were experimented and deeply analyzed. It was found that kerosene contained blends had quite similar combustion characteristics with those of D2. Mass fuel consumption and Bscf were slightly increased for blend fuels. HC emissions slightly increased while NOx emissions considerably reduced for blends. It was resulted that high percentages of biodiesel can be a potential substitute for diesel fuel provided that it is used as blending fuel with certain amounts of kerosene. - Highlights: • Effects of kerosene and diesel addition to biodiesel in a diesel engine were investigated. • B80&K10 and B80&K10&D10 were tested and comparisons have been made with D2. • Similar fuel properties and combustion parameters have been found for all fuels. • Heat release initiated earlier for B80&K10 and B80&K10&D10. • CO and NOx emissions are lowered for B80&K10 and B80&K10&D10.

Combustion Characteristics of CI Diesel Engine Fuelled With Blends of Jatropha Oil Biodiesel

Science.gov (United States)

Singh, Manpreet; Yunus Sheikh, Mohd.; Singh, Dharmendra; Nageswara rao, P.

2018-03-01

Jatropha Curcas oil is a non-edible oil which is used for Jatropha biodiesel (JBD) production. Jatropha biodiesel is produced using transesterification technique and it is used as an alternative fuel in CI diesel engine without any hardware modification. Jatropha biodiesel is used in CI diesel engine with various volumetric concentrations (blends) such as JBD5, JBD15, JBD25, JBD35 and JBD45. The combustion parameters such as in-cylinder pressure, rate of pressure rise, net heat release, cumulative heat release, mass fraction burned are analyzed and compared for all blends combustion data with mineral diesel fuel (D100).

Piston surface heat transfer during combustion in large marine diesel engines

DEFF Research Database (Denmark)

Jensen, Michael Vincent; Walther, Jens Honore

2010-01-01

In the design process of large marine diesel engines information on the maximum heat load on the piston surface experienced during the engine cycle is an important parameter. The peak heat load occurs during combustion when hot combustion products impinge on the piston surface. Although the maximum...... heat load is only present for a short time of the total engine cycle, it is a severe thermal load on the piston surface. At the same time, cooling of the piston crown is generally more complicated than cooling of the other components of the combustion chamber. This can occasionally cause problems...... with burning off piston surface material. In this work the peak heat load on the piston surface of large marine diesel engines during combustion was investigated. Measurements of the instantaneous surface temperature and surface heat flux on pistons in large marine engines are difficult due to expensive...

Improving the performance and emission characteristics of a single cylinder diesel engine having reentrant combustion chamber using diesel and Jatropha methyl esters.

Science.gov (United States)

Premnath, S; Devaradjane, G

2015-11-01

The emissions from the Compression ignition (CI) engines introduce toxicity to the atmosphere. The undesirable carbon deposits from these engines are realized in the nearby static or dynamic systems such as vehicles, inhabitants, etc. The objective of this research work is to improve the performance and emission characteristics of a diesel engine in the modified re-entrant combustion chamber using a diesel and Jatropha methyl ester blend (J20) at three different injection pressures. From the literature, it is revealed that the shape of the combustion chamber and the fuel injection pressure have an impact on the performance and emission parameters of the CI engine. In this work, a re-entrant combustion chamber with three different fuel injection pressures (200, 220 and 240bars) has been used in the place of the conventional hemispherical combustion chamber for diesel and J20. From the experimental results, it is found that the re-entrant chamber improves the brake thermal efficiency of diesel and J20 in all the tested conditions. It is also found that the 20% blend of Jatropha methyl ester showed 4% improvement in the brake thermal efficiency in the re-entrant chamber at the maximum injection pressure. Environmental safety directly relates to the reduction in the undesirable effects on both living and non-living things. Currently environmental pollution is of major concern. Even with the stringent emission norms new methods are required to reduce the harmful effects from automobiles. The toxicity of carbon monoxide (CO) is well known. In the re-entrant combustion chamber, the amount of CO emission is reduced by 26% when compared with the conventional fuel operation of the engine. Moreover, the amount of smoke is reduced by 24% and hydrocarbons (HC) emission by 24%. Thus, the modified re-entrant combustion chamber reduces harmful pollutants such as unburned HC and CO as well as toxic smoke emissions. Copyright © 2015 Elsevier Inc. All rights reserved.

Semi-volatile and particulate emissions from the combustion of alternative diesel fuels.

Science.gov (United States)

Sidhu, S; Graham, J; Striebich, R

2001-01-01

Motor vehicle emissions are a major anthropogenic source of air pollution and contribute to the deterioration of urban air quality. In this paper, we report results of a laboratory investigation of particle formation from four different alternative diesel fuels, namely, compressed natural gas (CNG), dimethyl ether (DME), biodiesel, and diesel, under fuel-rich conditions in the temperature range of 800-1200 degrees C at pressures of approximately 24 atm. A single pulse shock tube was used to simulate compression ignition (CI) combustion conditions. Gaseous fuels (CNG and DME) were exposed premixed in air while liquid fuels (diesel and biodiesel) were injected using a high-pressure liquid injector. The results of surface analysis using a scanning electron microscope showed that the particles formed from combustion of all four of the above-mentioned fuels had a mean diameter less than 0.1 microm. From results of gravimetric analysis and fuel injection size it was found that under the test conditions described above the relative particulate yields from CNG, DME, biodiesel, and diesel were 0.30%. 0.026%, 0.52%, and 0.51%, respectively. Chemical analysis of particles showed that DME combustion particles had the highest soluble organic fraction (SOF) at 71%, followed by biodiesel (66%), CNG (38%) and diesel (20%). This illustrates that in case of both gaseous and liquid fuels, oxygenated fuels have a higher SOF than non-oxygenated fuels.

Combustion Property Analysis and Control System for the Dynamics of a Single Cylinder Diesel Engine

Directory of Open Access Journals (Sweden)

Bambang Wahono

2013-12-01

Full Text Available Corresponding to global environment problems in recent year, the technology for reducing fuel consumption and exhaust gas emission of engine was needed. Simulation of transient engine response is needed to predict engine performance that frequently experience rapid changes of speed. The aim of this research is to develop a non-linear dynamic control model for direct injection single cylinder diesel engine which can simulate engine performance under transient conditions. In this paper, the combustion model with multistage injection and conducted experiments in the transient conditions to clarify the combustion characteristics was proposed. In order to perform the analysis of acceleration operation characteristics, it was built a Model Predictive Control (MPC to reproduce the characteristic values of the exhaust gas and fuel consumption from the control parameters in particular. Finally, MPC is an effective method to perform the analysis of characteristic in diesel engine under transient conditions.

Effects of ambient oxygen concentration on biodiesel and diesel spray combustion under simulated engine conditions

KAUST Repository

Zhang, Ji

2013-08-01

This study investigates the effect of ambient oxygen concentration on biodiesel and diesel spray combustion under simulated compression-ignition engine conditions in a constant-volume chamber. The apparent heat release rate (AHRR) is calculated based on the measured pressure. High-speed imaging of OH* chemiluminescence and natural luminosity (NL) is employed to visualize the combustion process. Temporally and spatially resolved NL and OH* contour plots are obtained. The result indicates that AHRR depends monotonically on the ambient oxygen concentration for both fuels. A lower oxygen concentration yields a slower AHRR increase rate, a lower peak AHRR value, but a higher AHRR value during the burn-out stage when compared with higher ambient oxygen concentration conditions. OH* chemiluminescence and NL contours indicate that biodiesel may experience a longer premixed-combustion duration. The 18% ambient O2 condition works better for biodiesel than diesel in reducing soot luminosity. With 12% O2, diesel combustion is significantly degraded. However, both fuels experience low temperature combustion at 10% O2. These results may imply that biodiesel is able to achieve the desired lower soot production under a moderate oxygen level with higher combustion efficiency, while diesel needs to be burned under very low ambient oxygen concentration for low soot production. © 2013 Elsevier Ltd.

Effects of ambient oxygen concentration on biodiesel and diesel spray combustion under simulated engine conditions

KAUST Repository

Zhang, Ji; Jing, Wei; Roberts, William L.; Fang, Tiegang

2013-01-01

This study investigates the effect of ambient oxygen concentration on biodiesel and diesel spray combustion under simulated compression-ignition engine conditions in a constant-volume chamber. The apparent heat release rate (AHRR) is calculated based on the measured pressure. High-speed imaging of OH* chemiluminescence and natural luminosity (NL) is employed to visualize the combustion process. Temporally and spatially resolved NL and OH* contour plots are obtained. The result indicates that AHRR depends monotonically on the ambient oxygen concentration for both fuels. A lower oxygen concentration yields a slower AHRR increase rate, a lower peak AHRR value, but a higher AHRR value during the burn-out stage when compared with higher ambient oxygen concentration conditions. OH* chemiluminescence and NL contours indicate that biodiesel may experience a longer premixed-combustion duration. The 18% ambient O2 condition works better for biodiesel than diesel in reducing soot luminosity. With 12% O2, diesel combustion is significantly degraded. However, both fuels experience low temperature combustion at 10% O2. These results may imply that biodiesel is able to achieve the desired lower soot production under a moderate oxygen level with higher combustion efficiency, while diesel needs to be burned under very low ambient oxygen concentration for low soot production. © 2013 Elsevier Ltd.

Performance diagnostic system for emergency diesel generators

International Nuclear Information System (INIS)

Logan, K.P.

1991-01-01

Diesel generators are commonly used for emergency backup power at nuclear stations. Emergency diesel generators (EDGs) are subject to both start-up and operating failures, due to infrequent and fast-start use. EDG reliability can be critical to plant safety, particularly when station blackout occurs. This paper describes an expert diagnostic system designed to consistently evaluate the operating performance of diesel generators. The prototype system is comprised of a suite of sensor monitoring, cylinder combustion analyzing, and diagnostic workstation computers. On-demand assessments of generator and auxiliary equipment performance are provided along with color trend displays comparing measured performance to reference-normal conditions

Chemiluminescence analysis of the effect of butanol-diesel fuel blends on the spray-combustion process in an experimental common rail diesel engine

Directory of Open Access Journals (Sweden)

Merola Simona Silvia S.

2015-01-01

Full Text Available Combustion process was studied from the injection until the late combustion phase in an high swirl optically accessible combustion bowl connected to a single cylinder 2-stroke high pressure common rail compression ignition engine. Commercial diesel and blends of diesel and n-butanol (20%: BU20 and 40%: BU40 were used for the experiments. A pilot plus main injection strategy was investigated fixing the injection pressure and fuel mass injected per stroke. Two main injection timings and different pilot-main dwell times were explored achieving for any strategy a mixing controlled combustion. Advancing the main injection start, an increase in net engine working cycle (>40% together with a strong smoke number decrease (>80% and NOx concentration increase (@50% were measured for all pilot injection timings. Compared to diesel fuel, butanol induced a decrease in soot emission and an increase in net engine working area when butanol ratio increased in the blend. A noticeable increase in NOx was detected at the exhaust for BU40 with a slight effect of the dwell-time. Spectroscopic investigations confirmed the delayed auto-ignition (~60 ms of the pilot injection for BU40 compared to diesel. The spectral features for the different fuels were comparable at the start of combustion process, but they evolved in different ways. Broadband signal caused by soot emission, was lower for BU40 than diesel. Different balance of the bands at 309 and 282 nm, due to different OH transitions, were detected between the two fuels. The ratio of these intensities was used to follow flame temperature evolution.

Simulation of low temperature combustion mechanism of different combustion-supporting agents in close-coupled DOC and DPF system.

Science.gov (United States)

Jiao, Penghao; Li, Zhijun; Li, Qiang; Zhang, Wen; He, Li; Wu, Yue

2018-07-01

In the coupled Diesel Oxidation Catalyst (DOC) and Diesel Particular Filter (DPF) system, soot cannot be completely removed by only using the passive regeneration. And DPF active regeneration is necessary. The research method in this paper is to spray different kinds of combustion-supporting agents to the DOC in the front of the DPF. Therefore, the low temperature combustion mechanism of different kinds of combustion-supporting agents in DOC was studied, in order to grasp the law of combustion in DOC, and the influence of follow-up emission on DPF removal of soot. During the study, CH 4 H 2 mixture and diesel (n-heptane + toluene) were used as combustion-supporting agents respectively. The simplified mechanisms of two kinds of gas mixtures used as the combustion-supporting agents in DPF have been constructed and testified in the paper. In this paper, the combustion and emission conditions of the two combustion-supporting agents were analyzed so as to meet the practical requirements of different working conditions. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Analysis the ECFM-3Z Combustion Model for Simulating the Combustion Process and Emission Characteristics in a HSDI Diesel Engine

Directory of Open Access Journals (Sweden)

Raouf Mobasheri

2015-12-01

Full Text Available An advanced CFD simulation has been performed to analyze the ECFM-3Z (Extended Coherent Flame Model-3Z combustion model for simulating the combustion process and emission characteristics in a high speed direct injection (HSDI diesel engine. A four cylinders, HSDI diesel engine based on a Ford production engine with a 2nd generation Delphi common rail fuel injection system has been modeled in this research. 3D CFD simulation was carried out from intake valve closing (IVC to exhaust valve opening (EVO. A good agreement of calculated and measured in-cylinder pressure trace as well as pollutant formation trends could be observed for all investigated operating points. Based on the confidence gained from validation, the study is extended to evaluate the effect of fuel injection timing on engine performance and emissions. For this purpose, a comprehensive study of the effect of injection timing with respect to performance and emissions has been considered. Three main injection timing, (1 2.65 BTDC, (2 0.65 BTDC and (3 1.35 ATDC, all with 30 crank angle pilot separations has been used to investigate the effect of the injection timing. The results show that the current methodology can be applied as a beneficial tool for analyzing the parameters of the diesel combustion under HSDI operating condition.

COMBUSTION CHARACTERISTICS OF DIESEL ENGINE OPERATING ON JATROPHA OIL METHYL ESTER

Directory of Open Access Journals (Sweden)

Doddayaraganalu Amasegoda Dhananjaya

2010-01-01

Full Text Available Fuel crisis because of dramatic increase in vehicular population and environmental concerns have renewed interest of scientific community to look for alternative fuels of bio-origin such as vegetable oils. Vegetable oils can be produced from forests, vegetable oil crops, and oil bearing biomass materials. Non-edible vegetable oils such as jatropha oil, linseed oil, mahua oil, rice bran oil, karanji oil, etc., are potentially effective diesel substitute. Vegetable oils have reasonable energy content. Biodiesel can be used in its pure form or can be blended with diesel to form different blends. It can be used in diesel engines with very little or no engine modifications. This is because it has combustion characteristics similar to petroleum diesel. The current paper reports a study carried out to investigate the combustion, performance and emission characteristics of jatropha oil methyl ester and its blend B20 (80% petroleum diesel and 20% jatropha oil methyl ester and diesel fuel on a single-cylinder, four-stroke, direct injections, water cooled diesel engine. This study gives the comparative measures of brake thermal efficiency, brake specific energy consumption, smoke opacity, HC, NOx, ignition delay, cylinder peak pressure, and peak heat release rates. The engine performance in terms of higher thermal efficiency and lower emissions of blend B20 fuel operation was observed and compared with jatropha oil methyl ester and petroleum diesel fuel for injection timing of 20° bTDC, 23° bTDC and 26° bTDC at injection opening pressure of 220 bar.

Combustion of n-butanol/diesel mixtures in prechamber diesel engines. Die Verbrennung von n-Butanol-Dieselkraftstoff-Gemischen im Vorkammer-Dieselmotor

Energy Technology Data Exchange (ETDEWEB)

Sperling, E

1989-01-01

Systematic tests showed that n-butane was the most promising diesel fuel substitute. Mixtures of n-butanol and diesel fuel were tested on an engine test bench, and the performance was compared with commercial diesel fuels. Pollutant concentrations in the exhaust (soot, particulates, and NO/sub x/) were lower than with unmixed diesel fuel, while the engine performance remained more or less constant. In the problematic operating ranges, partial thermal insulation of the combustion chamber improved the performance of the n-butanol/diesel fuel mixture. (orig.) With 60 figs.

Tabulated chemical kinetics for efficient and detailed simulations of diesel engine combustion

NARCIS (Netherlands)

Bekdemir, C.

2012-01-01

Efficient and detailed computational tools to simulate engine combustion are of great importance. The internal combustion engine will remain the primary mean for transportation in the decades to come. Especially diesel engines are, and become increasingly more, popular because of their high

Influence of distillation on performance, emission, and combustion of a DI diesel engine, using tyre pyrolysis oil diesel blends

Directory of Open Access Journals (Sweden)

Murugan Sivalingam

2008-01-01

Full Text Available Conversion of waste to energy is one of the recent trends in minimizing not only the waste disposal but also could be used as an alternate fuel for internal combustion engines. Fuels like wood pyrolysis oil, rubber pyrolysis oil are also derived through waste to energy conversion method. Early investigations report that tyre pyrolysis oil derived from vacuum pyrolysis method seemed to possess properties similar to diesel fuel. In the present work, the crude tyre pyrolisis oil was desulphurised and distilled to improve the properties and studied the use of it. Experimental studies were conducted on a single cylinder four-stroke air cooled engine fuelled with two different blends, 30% tyre pyrolysis oil and 70% diesel fuel (TPO 30 and 30% distilled tyre pyrolysis oil and 70% diesel fuel (DTPO 30. The results of the performance, emission and combustion characteristics of the engine indicated that NOx is reduced by about 8% compared to tire pyrolysis oil and by about 10% compared to diesel fuel. Hydrocarbon emission is reduced by about 2% compared to TPO 30 operation. Smoke increased for DTPO 30 compared to TPO 30 and diesel fuel.

Advanced closed loop combustion control of a LTC diesel engine based on in-cylinder pressure signals

International Nuclear Information System (INIS)

Carlucci, A.P.; Laforgia, D.; Motz, S.; Saracino, R.; Wenzel, S.P.

2014-01-01

Highlights: • We have proposed an in-cylinder pressure-based closed loop combustion control. • We have tested the control on an engine at the test bench. • We have tested the control on the engine equipping a Euro 6-compliant vehicle. • The control is effective in increasing torque stability and reduce engine noise. - Abstract: The adoption of diesel LTC combustion concepts is widely recognised as a practical way to reduce simultaneously nitric oxides and particulate emission levels from diesel internal combustion engines. However, several challenges have to be faced up when implementing diesel LTC concepts in real application vehicles. In particular, achieving acceptable performance concerning the drivability comfort, in terms of output torque stability and combustion noise during engine dynamic transients, is generally a critical point. One of the most promising solutions to improve the LTC combustion operation lays in the exploitation of closed loop combustion control, based on in-cylinder pressure signals. In this work, the application of an in-cylinder pressure-based closed loop combustion control to a Euro 6-compliant demonstrator vehicle has been developed. The main challenges deriving from the control of the LTC combustion, directly affecting the engine/vehicle performance, have been analysed in detail. In order to overcome these drawbacks, a new control function, integrated into the base closed loop system, has been designed. The performance of the new function have been experimentally tested at the engine test bench. Results showed a significant enhancement of the LTC operation, in terms of both combustion stability and noise reduction during engine transients. The new function was also implemented on a real vehicle, thus proving the potential of the new control concept in realistic operating conditions

Numerical modeling of spray combustion in DI diesel engine using partially stirred reactor (PaSR) model

International Nuclear Information System (INIS)

Khaleghi, H.; Hosseini, S.M.

2003-01-01

In recent years special attention has been paid to the topic of diesel engine combustion. Various combustion models are used in CFD codes. In this paper Partially Stirred Reactor (PaSR) model, one of the newest turbulent combustion models, is introduced. This model has been employed in conjunction with the non-iterative PISO algorithm to calculate spray combustion in an axi-symmetric, direct injection diesel engine. Qualitative consideration of the results shows very good agreement with physical expectations and other numerical and experimental results. (author)

Numerical analysis for controlling mixture heterogeneity to reduce abrupt combustion in diesel PCCI combustion

Energy Technology Data Exchange (ETDEWEB)

Nishiwaki, Kazuie [Ritsumeikan University (Japan); Kojima, Takafumi [Takamatsu National College of Technology (Japan)

2010-07-01

In the energy sector, stringent regulations have been implemented on combustion emissions in order to address health and environmental concerns and help improve air quality. A novel combustion mode, premixed charge compression ignition (PCCI), can improve the emissions performance of an engine over that of conventional diesel. The aim of this research is to develop a model to analyze the mixture formation in the PCCI combustion mode. A numerical model was developed and was applied to an engine and the results were compared to experimental results. It was found that the model results are in agreement with the experimental results. This paper presented a novel LES computer model and demonstrated that it is efficient in predicting the mixture formation in the PCCI combustion mode.

Performance, emission, and combustion characteristics of twin-cylinder common rail diesel engine fuelled with butanol-diesel blends.

Science.gov (United States)

Lamani, Venkatesh Tavareppa; Yadav, Ajay Kumar; Gottekere, Kumar Narayanappa

2017-10-01

Nitrogen oxides and smoke are the substantial emissions for the diesel engines. Fuels comprising high-level oxygen content can have low smoke emission due to better oxidation of soot. The objective of the paper is to assess the potential to employ oxygenated fuel, i.e., n-butanol and its blends with the neat diesel from 0 to 30% by volume. The experimental and computational fluid dynamic (CFD) simulation is carried out to estimate the performance, combustion, and exhaust emission characteristics of n-butanol-diesel blends for various injection timings (9°, 12°, 15°, and 18°) using modern twin-cylinder, four-stroke, common rail direct injection (CRDI) engine. Experimental results reveal the increase in brake thermal efficiency (BTE) by ~ 4.5, 6, and 8% for butanol-diesel blends of 10% (Bu10), 20% (Bu20), and 30% (Bu30), respectively, compared to neat diesel (Bu0). Maximum BTE for Bu0 is 38.4%, which is obtained at 12° BTDC; however, for Bu10, Bu20 and Bu30 are 40.19, 40.9, and 41.7%, which are obtained at 15° BTDC, respectively. Higher flame speed of n-butanol-diesel blends burn a large amount of fuel in the premixed phase, which improves the combustion as well as emission characteristics. CFD and experimental results are compared and validated for all fuel blends for in-cylinder pressure and nitrogen oxides (NO x ), and found to be in good agreement. Both experimental and simulation results witnessed in reduction of smoke opacity, NO x , and carbon monoxide emissions with the increasing n-butanol percentage in diesel fuel.

Development and application of multi-zone model for combustion and pollutants formation in direct injection diesel engine running with vegetable oil or its bio-diesel

International Nuclear Information System (INIS)

Rakopoulos, C.D.; Antonopoulos, K.A.; Rakopoulos, D.C.

2007-01-01

A multi-zone model for calculation of the closed cycle of a direct injection (DI) Diesel engine is presented and applied for the interesting case of its operation with vegetable oil (cottonseed) or its derived bio-diesel (methyl ester) as fuels, which recently are considered as promising alternatives (bio-fuels) to petroleum distillates. Although there are many experimental studies, there is an apparent scarcity of theoretical models scrutinizing the formation mechanisms of combustion generated emissions when using these fuels. The model is two dimensional, multi-zone with the issuing jets (from the nozzle) divided into several discrete volumes, called 'zones', formed along the direction of the fuel injection and across it. The model follows each zone, with its own time history, as the spray penetrates into the swirling air environment (forming the non-burning zone) of the combustion chamber, before and after wall impingement. Droplet evaporation and jet mixing models are used to determine the amount of fuel and entrained air in each zone available for combustion. The mass, energy and state equations are applied in each zone to yield local temperatures and cylinder pressure histories. The concentrations of the various constituents are calculated by adopting a chemical equilibrium scheme for the C-H-O-N system of 11 species considered, together with the chemical rate equations for the calculation of nitric oxide (NO). A model for evaluation of soot formation and oxidation rates is included. The results from the relevant computer program for the in cylinder pressure, exhaust nitric oxide concentration (NO) and soot density are compared favorably with the corresponding measurements from an experimental investigation conducted on a fully automated test bed, standard 'Hydra', DI Diesel engine installed at the authors' laboratory. Iso-contour plots of equivalence ratio, temperature, NO and soot inside the combustion chamber at various instants of time when using these

A computational study of free-piston diesel engine combustion

Energy Technology Data Exchange (ETDEWEB)

Mikalsen, R.; Roskilly, A.P. [Sir Joseph Swan Institute for Energy Research, Newcastle University, Devonshire Building, Newcastle upon Tyne, NE1 7RU (United Kingdom)

2009-07-15

This paper investigates the in-cylinder gas motion, combustion process and nitrogen oxide formation in a free-piston diesel engine and compares the results to those of a conventional engine, using a computational fluid dynamics engine model. Enhanced radial gas flow (squish and reverse squish) around top dead centre is found for the free-piston engine compared to a conventional engine, however it is found that this has only minor influence on the combustion process. A higher heat release rate from the pre-mixed combustion phase due to an increased ignition delay was found, along with potential reductions in nitrogen oxides emissions formation for the free-piston engine. (author)

Computational Study of Stratified Combustion in an Optical Diesel Engine

KAUST Repository

Jaasim, Mohammed; Hernandez Perez, Francisco; Vallinayagam, R.; Vedharaj, S.; Johansson, Bengt; Im, Hong G.

2017-01-01

Full cycle simulations of KAUST optical diesel engine were conducted in order to provide insights into the details of fuel spray, mixing, and combustion characteristics at different start of injection (SOI) conditions. Although optical diagnostics

Optimization of combustion chamber geometry for stoichiometric diesel combustion using a micro genetic algorithm

Energy Technology Data Exchange (ETDEWEB)

Park, Sung Wook

2010-11-15

This paper describes the optimization of combustion chamber geometry and engine operating conditions for stoichiometric diesel combustion, targeting lower gross indicated specific fuel consumption. The KIVA code, coupled with a micro genetic algorithm population of nine for each generation was used. The optimization variables were composed of ten variables related to the combustion chamber geometry and engine operating conditions. In addition, an auto mesh generator was developed for generating various kinds of combustion chambers, such as open-crater, re-entrant, deep, and shallow types. In addition, the computational models were validated against the experimental results for a stoichiometric process in terms of the combustion pressure history and emissions. Through the preset optimization, a 35% improvement in the gross indicated that specific fuel consumption was achieved. In addition, the optimization results showed that the optimum engine operating conditions employed a premixed charge compression ignition combustion regime with early injection and a narrow spray included angle. Furthermore, a higher boost pressure was used to prevent fuel film formation. (author)

Characterization of Diesel and Gasoline Compression Ignition Combustion in a Rapid Compression-Expansion Machine using OH* Chemiluminescence Imaging

Science.gov (United States)

Krishnan, Sundar Rajan; Srinivasan, Kalyan Kumar; Stegmeir, Matthew

2015-11-01

Direct-injection compression ignition combustion of diesel and gasoline were studied in a rapid compression-expansion machine (RCEM) using high-speed OH* chemiluminescence imaging. The RCEM (bore = 84 mm, stroke = 110-250 mm) was used to simulate engine-like operating conditions at the start of fuel injection. The fuels were supplied by a high-pressure fuel cart with an air-over-fuel pressure amplification system capable of providing fuel injection pressures up to 2000 bar. A production diesel fuel injector was modified to provide a single fuel spray for both diesel and gasoline operation. Time-resolved combustion pressure in the RCEM was measured using a Kistler piezoelectric pressure transducer mounted on the cylinder head and the instantaneous piston displacement was measured using an inductive linear displacement sensor (0.05 mm resolution). Time-resolved, line-of-sight OH* chemiluminescence images were obtained using a Phantom V611 CMOS camera (20.9 kHz @ 512 x 512 pixel resolution, ~ 48 μs time resolution) coupled with a short wave pass filter (cut-off ~ 348 nm). The instantaneous OH* distributions, which indicate high temperature flame regions within the combustion chamber, were used to discern the characteristic differences between diesel and gasoline compression ignition combustion. The authors gratefully acknowledge facilities support for the present work from the Energy Institute at Mississippi State University.

Assessment of n-pentanol/Calophyllum inophyllum/diesel blends on the performance, emission, and combustion characteristics of a constant-speed variable compression ratio direct injection diesel engine.

Science.gov (United States)

Ramakrishnan, Purnachandran; Kasimani, Ramesh; Peer, Mohamed Shameer; Rajamohan, Sakthivel

2018-05-01

Alcohol is used as an additive for a long time with the petroleum-based fuels. In this study, the higher alcohol, n-pentanol, was used as an additive to Calophyllum inophyllum (CI) biodiesel/diesel blends at 10, 15, and 20% by volume. In all blends, the ratio of CI was maintained at 20% by volume. The engine characteristics of the pentanol fuel blends were compared with the diesel and CI20 (Calophyllum inophyllum 20% and diesel 80%) biodiesel blend. The nitrogen oxide (NO) emission of the pentanol fuel blends showed an increased value than CI20 and neat diesel fuel. The carbon dioxide (CO 2 ) also increased with increase in pentanol addition with the fuel blends than CI20 fuel blend and diesel. The carbon monoxide (CO) and hydrocarbon (HC) emissions were decreased with increase in pentanol proportion in the blend than the CI20 fuel and diesel. The smoke emission was reduced and the combustion characteristics of the engine were also improved by using pentanol blended fuels. From this investigation, it is suggested that 20% pentanol addition with the biodiesel/diesel fuel is suitable for improved performance and combustion characteristics of a diesel engine without any engine modifications, whereas CO 2 and NO emissions increased with addition of pentanol due to effective combustion.

Combustion Characterization and Ignition Delay Modeling of Low- and High-Cetane Alternative Diesel Fuels in a Marine Diesel Engine

OpenAIRE

Petersen, John; Seivwright, Doug; Caton, Patrick; Millsaps, Knox

2014-01-01

The article of record as published may be found at http://dx.doi.org/10.1021/ef500565t In support of an ongoing U.S. Navy alternative fuel evaluation program, the combustion characteristics of two very different alternative diesel fuels were evaluated in a direct-injection marine diesel engine across a variety of speeds and loads. The fuels were an algal-based hydrotreated renewable diesel fuel (HRD) with cetane number of ∼75 and a synthetic paraffinic kerosene (SPK) with cetane n...

Evaporation and Ignition Characteristics of Water Emulsified Diesel under Conventional and Low Temperature Combustion Conditions

Directory of Open Access Journals (Sweden)

Zhaowen Wang

2017-07-01

Full Text Available The combination of emulsified diesel and low temperature combustion (LTC technology has great potential in reducing engine emissions. A visualization study on the spray and combustion characteristics of water emulsified diesel was conducted experimentally in a constant volume chamber under conventional and LTC conditions. The effects of ambient temperature on the evaporation, ignition and combustion characteristics of water emulsified diesel were studied under cold, evaporating and combustion conditions. Experimental results showed that the ambient temperature had little effect on the spray structures, in terms of the liquid core length, the spray shape and the spray area. However, higher ambient temperature slightly reduced the Sauter Mean Diameter (SMD of the spray droplets. The auto-ignition delay time increased significantly with the decrease of the ambient temperature. The ignition process always occurred at the entrainment region near the front periphery of the liquid core. This entrainment region was evolved from the early injected fuel droplets which were heated and mixed by the continuous entrainment until the local temperature and equivalence ratio reached the ignition condition. The maximum value of integrated natural flame luminosity (INFL reduced by 60% when the ambient temperature dropped from 1000 to 800 K, indicating a significant decrease of the soot emissions could be achieved by LTC combustion mode than the conventional diesel engines.

Diesel combustion and emissions formation using multiple 2-D imaging diagnostics

Energy Technology Data Exchange (ETDEWEB)

Dec, J.E. [Sandia National Labs., Livermore, CA (United States)

1997-12-31

Understanding how emissions are formed during diesel combustion is central to developing new engines that can comply with increasingly stringent emission standards while maintaining or improving performance levels. Laser-based planar imaging diagnostics are uniquely capable of providing the temporally and spatially resolved information required for this understanding. Using an optically accessible research engine, a variety of two-dimensional (2-D) imaging diagnostics have been applied to investigators of direct-injection (DI) diesel combustion and emissions formation. These optical measurements have included the following laser-sheet imaging data: Mie scattering to determine liquid-phase fuel distributions, Rayleigh scattering for quantitative vapor-phase-fuel/air mixture images, laser induced incandescence (LII) for relative soot concentrations, simultaneous LII and Rayleigh scattering for relative soot particle-size distributions, planar laser-induced fluorescence (PLIF) to obtain early PAH (polyaromatic hydrocarbon) distributions, PLIF images of the OH radical that show the diffusion flame structure, and PLIF images of the NO radical showing the onset of NO{sub x} production. In addition, natural-emission chemiluminescence images were obtained to investigate autoignition. The experimental setup is described, and the image data showing the most relevant results are presented. Then the conceptual model of diesel combustion is summarized in a series of idealized schematics depicting the temporal and spatial evolution of a reacting diesel fuel jet during the time period investigated. Finally, recent PLIF images of the NO distribution are presented and shown to support the timing and location of NO formation hypothesized from the conceptual model.

Analysis of combustion behavior in DI diesel engine at low temperature; DI diesel engine ni okeru teionji no nensho kyodo kaiseki

Energy Technology Data Exchange (ETDEWEB)

Kuzuya, Y; Shibata, H [Nippon Soken, Inc., Tokyo (Japan); Aoki, S; Itatsu, T [Toyota Motor Corp., Aichi (Japan)

1997-10-01

For NOx reduction of a DI diesel engine, the retard of fuel injection timing is effective. However, it causes the white smoke at low temperature and low load. To analyze the mechanism of white smoke generation, a new visualizing system of fuel spray and flame behavior has been developed. This system can be also applied to a 4-valves per cylinder production engine by integrating two optical systems for image and lighting. From the visualization of the fuel spray and the flame behavior in the combustion chamber at low temperature, it has been proved that prompt fuel evaporation before reaching the wall surface of combustion chamber is required to reduce the white smoke. 6 refs., 10 figs., 3 tabs.

Combustion and Gasification Collection of Diesel Soot by Means of Microwave Heating

Directory of Open Access Journals (Sweden)

Xueshi YAO

2014-06-01

Full Text Available The experiment of integrated purification of diesel soot was made by means of microwave heating. The experiment includes combustion and gasification collection. The catalytic effect of ceramic carrier was used in the combustion process. In order to improve the purification efficiency of PM2.5 particles, the surfactants were used in gasification collection. The model of computer control was set up so that the purification course could be controlled. The experimental principle was analyzed. Experiment result indicated that the diesel soot purifying efficiency is more than 90 %. The purification efficiency can be improved further by the optimization design of experimental device.

Improvement of combustion in a direct injection diesel engine by micro-hole nozzle; Micro hole nozzle wo mochiita chokusetsu funshashiki diesel kikan no nensho kaizen

Energy Technology Data Exchange (ETDEWEB)

Murata, M. [Keio University, Tokyo (Japan); Kobori, S. [Tokyo Institute of Technology, Tokyo (Japan); Iida, N. [Keio University, Tokyo (Japan). Faculty of Science and Technology

2000-07-25

In an attempt to promote the atomization of fuel spray and the mixing of fuel and air in diesel engines, a micro-hole nozzle which has orifices with a diameter smaller than 0.10mm was developed. In this study, the combustion tests were carried out using a single cylinder diesel engine equipped with a micro-hole nozzle and a common rail type high-pressure fuel injection system. A comparison with the results of a conventional nozzle experiment showed that the peak of initial premixed combustion increased, but the peak of diffusion combustion decreased. As a result, when nozzle orifice diameter become small from {phi} 0.15 mm to {phi} 0.10 mm, the combustion was accompanied by smokeless with the same levels of NO{sub x} emission and fuel economy. And results of a comparison the toroidal type chamber with the shallow dish type chamber revealed that the optimization of combustion chamber is necessary for the increase of the injection stage with increasing of the number of nozzle orifice. If an orifice diameter becomes {phi} 0.06 mm, the diffusion combustion can not be observed and the combustion is formed of only premixed combustion. The combustion in the case of {phi} 0.06 mm was accompanied with the drastic deterioration of fuel economy, smoke and HC with all over load. But the micro-hole nozzle has a potential for the formation of the lean and homogeneous premixed mixture until the fuel-air mixture ignites. (author)

Development of a self-ignition and combustion model for diesel engines; Modelisation de l`auto-inflammation et de la combustion pour les moteurs diesel

Energy Technology Data Exchange (ETDEWEB)

Pires Da Cruz, A.

1997-12-09

The work concerns self-ignition and combustion modelling in Diesel engines. Special attention is given to turbulence induced effects. Only gas fuel injection is taken into account. Turbulent mixing is identified as one of the main parameters controlling self-ignition in Diesel engines. However, turbulence effects are often neglected by models currently used in engine calculation codes. A new model based on results obtained by direct numerical simulation (DNS) is proposed. It includes turbulence effects by means of the scalar dissipation rate and presumed pdf of the mixture fraction and a chemical reaction progress variable. The model is validated through several steps. First, its results are compared to DNS in simple mixing and self-ignition cases. Then, its averaged version is integrated into the KIVA2-MB calculation code, where its behavior is tested in a one dimensional version and compared to other formulations. Finally, the model is validated with comparisons to experimental results of methane injection into a high pressure combustion chamber filled with hot air. The combustion chamber allows large optical access and therefore, optical diagnostics can be made. (author) 101 refs.

Soot measurements for diesel and biodiesel spray combustion under high temperature highly diluted ambient conditions

KAUST Repository

Zhang, Ji

2014-11-01

This paper presents the soot temperature and KL factor for biodiesel, namely fatty acid methyl ester (FAME) and diesel fuel combustion in a constant volume chamber using a two-color technique. The KL factor is a parameter for soot concentration, where K is an absorption coefficient and proportional to the number density of soot particles, L is the geometric thickness of the flame along the optical detection axis, and KL factor is proportional to soot volume fraction. The main objective is to explore a combustion regime called high-temperature and highly-diluted combustion (HTHDC) and compare it with the conventional and low-temperature combustion (LTC) modes. The three different combustion regimes are implemented under different ambient temperatures (800 K, 1000 K, and 1400 K) and ambient oxygen concentrations (10%, 15%, and 21%). Results are presented in terms of soot temperature and KL factor images, time-resolved pixel-averaged soot temperature, KL factor, and spatially integrated KL factor over the soot area. The time-averaged results for these three regimes are compared for both diesel and biodiesel fuels. Results show complex combined effects of the ambient temperature and oxygen concentration, and that two-color temperature for the HTHDC mode at the 10% oxygen level can actually be lower than the conventional mode. Increasing ambient oxygen and temperature increases soot temperature. Diesel fuel results in higher soot temperature than biodiesel for all three regimes. Results also show that diesel and biodiesel fuels have very different burning and sooting behavior under the three different combustion regimes. For diesel fuel, the HTHDC regime offers better results in terms of lower soot than the conventional and LTC regimes, and the 10% O2, 1400 K ambient condition shows the lowest soot concentration while maintaining a moderate two-color temperature. For biodiesel, the 15% O2, 800 K ambient condition shows some advantages in terms of reducing soot

Combustion and emissions characteristics of high n-butanol/diesel ratio blend in a heavy-duty diesel engine and EGR impact

International Nuclear Information System (INIS)

Chen, Zheng; Wu, Zhenkuo; Liu, Jingping; Lee, Chiafon

2014-01-01

Highlights: • Effects of EGR on high n-butanol/diesel ratio blend (Bu40) were investigated and compared with neat diesel (Bu00). • Bu40 has higher NOx due to wider combustion high-temperature region. • Bu40 has lower soot due to local lower equivalence ratio distribution. • Bu40 has higher CO due to lower gas temperature in the late expansion process. • For Bu40, EGR reduces NOx emissions dramatically with no obvious influence on soot. - Abstract: In this work, the combustion and emission fundamentals of high n-butanol/diesel ratio blend with 40% butanol (i.e., Bu40) in a heavy-duty diesel engine were investigated by experiment and simulation at constant engine speed of 1400 rpm and an IMEP of 1.0 MPa. Additionally, the impact of EGR was evaluated experimentally and compared with neat diesel fuel (i.e., Bu00). The results show that Bu40 has higher cylinder pressure, longer ignition delay, and faster burning rate than Bu00. Compared with Bu00, moreover, Bu40 has higher NOx due to wider combustion high-temperature region, lower soot due to local lower equivalence ratio distribution, and higher CO due to lower gas temperature in the late expansion process. For Bu40, EGR reduces NOx emissions dramatically with no obvious influence on soot. Meanwhile, there is no significant change in HC and CO emissions and indicated thermal efficiency (ITE) with EGR until EGR threshold is reached. When EGR rate exceeds the threshold level, HC and CO emissions increase dramatically, and ITE decreases markedly. Compared with Bu00, the threshold of Bu40 appears at lower EGR rate. Consequently, combining high butanol/diesel ratio blend with medium EGR has the potential to achieve ultra-low NOx and soot emissions simultaneously while maintaining high thermal efficiency level

Effects of oxygen enriched combustion on pollution and performance characteristics of a diesel engine

Directory of Open Access Journals (Sweden)

P. Baskar

2016-03-01

Full Text Available Oxygen enriched combustion is one of the attractive combustion technologies to control pollution and improve combustion in diesel engines. An experimental test was conducted on a single cylinder direct injection diesel engine to study the impact of oxygen enrichment on pollution and performance parameters by increasing the oxygen concentration of intake air from 21 to 27% by volume. The tests results show that the combustion process was improved as there is an increase in thermal efficiency of 4 to 8 percent and decrease in brake specific fuel consumption of 5 to 12 percent. There is also a substantial decrease in unburned hydro carbon, carbon mono-oxide and smoke density levels to the maximum of 40, 55 and 60 percent respectively. However, there is a considerable increase in nitrogen oxide emissions due to increased combustion temperature and extra oxygen available which needs to be addressed.

Review of the investigation of mixture formation and combustion process using rapid compression machine and direct visualization system

Science.gov (United States)

Jaat, M.; Khalid, Amir; Manshoor, B.; Ramsy, Him

2013-12-01

This paper reviews of some applications of optical visualization systems to compute the fuel-air mixing process during early stage of mixture formation in Diesel Combustion Engines. A number of studies have contributed to the understanding of fuel air mixing in DI diesel engine. This review has shown that the mixture formation process affects initial flame development. The review also found that injection pressure has a great effect on the mixture formation then the flame development and combustion characteristics. The method of the simulation of real phenomenon of diesel combustion with optical access rapid compression machine is also reviewed and experimental results are presented. The application of these methods to the investigation of diesel sprays highlights mechanisms which govern propagation and distribution of the formation of a combustible fuel-air mixture. A summary of the implementation of constant volume chamber and optical visualization system are shown in the accompanying tables and figures. The visualization of the formation process of diesel spray and its combustion in the diesel combustion chamber of diesel engine has been recognized as one of the best ways to understand the characteristics of the mixture formation.

Effects of ambient oxygen concentration on soot temperature and concentration for biodiesel and diesel spray combustion

KAUST Repository

Zhang, Ji; Jing, Wei; Roberts, William L.; Fang, Tiegang

2015-01-01

during biodiesel and diesel spray combustion. The experiment was implemented in a constant volume chamber system, where the ambient oxygen concentration varied from 21 to 10% and the ambient temperature was kept to 1,000 K. A high speed two-color

The effect of insulated combustion chamber surfaces on direct-injected diesel engine performance, emissions, and combustion

Science.gov (United States)

Dickey, Daniel W.; Vinyard, Shannon; Keribar, Rifat

1988-01-01

The combustion chamber of a single-cylinder, direct-injected diesel engine was insulated with ceramic coatings to determine the effect of low heat rejection (LHR) operation on engine performance, emissions, and combustion. In comparison to the baseline cooled engine, the LHR engine had lower thermal efficiency, with higher smoke, particulate, and full load carbon monoxide emissions. The unburned hydrocarbon emissions were reduced across the load range. The nitrous oxide emissions increased at some part-load conditions and were reduced slightly at full loads. The poor LHR engine performance was attributed to degraded combustion characterized by less premixed burning, lower heat release rates, and longer combustion duration compared to the baseline cooled engine.

Visualization research on spray atomization, evaporation and combustion processes of ethanol–diesel blend under LTC conditions

International Nuclear Information System (INIS)

Huang, Sheng; Deng, Peng; Huang, Ronghua; Wang, Zhaowen; Ma, Yinjie; Dai, Hui

2015-01-01

Highlights: • Spray combustion of E20 diesel in LTC condition shows a U-shape flame structure. • The chasing behavior of fuel spray exists near the spray axis. • Fuel ignition doesn’t initiate at the spray tip but in peripheral regions behind it. • An improper chamber structure may lead to a long post-combustion duration. - Abstract: Utilization of ethanol in diesel engines has been widely studied by means of engine experiments and emission detection. However, pertinent studies on the spray combustion process of ethanol–diesel blends are scarce. In order to verify the effect of ethanol in modern diesel engines, an experiment is conducted to visualize the spray combustion process of ethanol–diesel blend under LTC conditions. Stages including atomization, evaporation and combustion, are investigated individually to realize synergistic analysis. Meanwhile, considering the long time scale of combustion after fuel injection finishes, characteristics during and after injection period are both targeted in this paper. Moreover, measurement of macroscopic characteristics, such as spray tip penetration, spray spreading cone angle and flame lift off length, provides a quantitative profile of the spray structure. Results show that, evaporation, different from atomization, has little influence on spray penetration, but promotes the spray spreading angle and spray projected area. So does combustion, which enlarges the spray projected area further. Ignition takes place on the periphery behind the spray tip, then quickly extends to the whole head of the spray and forms a U-shape diffusion structure. After the injection period, the residual spray tail develops into wavelike structures due to absence of subsequent entrainment force. Also, the penetration speed falls greatly to an extent much slower than flame propagation, which frees the flame from the lift-off effect. Subsequently, the flame propagates upstream towards the nozzle orifice. After consumed all fuel in

Thermodynamic diagnosis of diesel and biodiesel combustion processes during load-increase transient sequences

International Nuclear Information System (INIS)

Armas, Octavio; Ballesteros, Rosario; Cardenas, María Dolores

2012-01-01

Highlights: ► Thermodynamic diagnosis was applied to diesel combustion process during transient operation. ► Comparative analysis of thermodynamic results with different biodiesel fuels has been carried out. ► Biodiesel fuels studied have a slight effect on timing of the combustion process. ► Methodology used can be applied to improve engine control when using different alternative fuels. -- Abstract: The study of the diesel combustion process is a current topic by the need of thermal efficiency improving and the reduction of pollutant emissions. This circumstance has forced researchers and manufacturers to optimize this process not only in steady state operating conditions but also during transient operation. A zero dimensional thermodynamic diagnostic model, with three species (air, fuel evaporated and burned products), has been used to characterize the combustion process during load increase transient sequences at two different engine speed. In both sequences, three variables were studied: the valve position of the exhaust gas recirculation (EGR), the elapsed time of the transition process and the type of fuel. Three biodiesel fuels were tested pure: rapeseed, soybean and sunflower which were compared to a commercial diesel fuel used as reference. Results are presented comparing the in-cylinder average maximum pressure and temperature, and the phasing of the combustion process based on the calculation of heat release. This study has allowed the detection of the effect of the tested engine parameters and the biodiesel fuels used on the in-cylinder thermodynamic conditions during the load transient sequences studied.

Improvement of D.I. diesel engine combustion using numerical simulation; Chokufun diesel kikan no nensho kaizen shuho. Suchi kaiseki ni yoru torikumi

Energy Technology Data Exchange (ETDEWEB)

Minami, T.; Adachi, T.; Isyii, Y. [Isuzu Motors Ltd., Tokyo (Japan)

1999-04-01

For the purpose of improving DI diesel engine combustion, it is important to predict air flow of intake and exhaust manifold, intake port flow, combustion chamber swirl and fuel spray combustion. This paper describes the application of numerical simulation to the engines, the analysis of phenomena and a problem of simulation model modification. (author)

An assessment of the dual-mode reactivity controlled compression ignition/conventional diesel combustion capabilities in a EURO VI medium-duty diesel engine fueled with an intermediate ethanol-gasoline blend and biodiesel

International Nuclear Information System (INIS)

Benajes, Jesús; García, Antonio; Monsalve-Serrano, Javier; Balloul, Iyad; Pradel, Gérard

2016-01-01

Highlights: • Reactivity controlled compression ignition regime utilized from 25% to 35% load. • Dual-mode reduces the regeneration periods of the diesel particulate filter. • The use of near-term available biofuels allows good performance and emissions. • Dual-mode leads to 2% greater efficiency than diesel combustion at high engine speeds. - Abstract: This work investigates the capabilities of the dual-mode reactivity controlled compression ignition/conventional diesel combustion engine operation to cover the full operating range of a EURO VI medium-duty diesel engine with compression ratio of 17.5:1. This concept is based on covering all the engine map switching between the reactivity controlled compression ignition and the conventional diesel combustion operating modes. Specifically, the benefits of reactivity controlled compression ignition combustion are exploited whenever possible according to certain restrictions, while the conventional diesel combustion operation is used to cover the zones of the engine map in which the reactivity controlled compression ignition operation is limited. The experiments were conducted using a single-cylinder research diesel engine derived from the multi-cylinder production engine. In addition, considering the mandatory presence of biofuels in the future context of road transport and the ability of ethanol to be blended with gasoline, the low reactivity fuel used in the study is a blend of 20% ethanol by volume with 80% of 95 octane number gasoline. Moreover, a diesel containing 7% of biodiesel has been used as high reactivity fuel. Firstly, a reactivity controlled compression ignition mapping is performed to check the operational limits of the concept in this engine platform. Later, based on the results, the potential of the dual-mode concept is discussed. Results suggest that, under the constraints imposed, reactivity controlled compression ignition combustion can be utilized between 25% and 35% load. In this region

Investigating the compression ignition combustion of multiple biodiesel/ULSD (ultra-low sulfur diesel) blends via common-rail injection

International Nuclear Information System (INIS)

Mangus, Michael; Kiani, Farshid; Mattson, Jonathan; Tabakh, Daniel; Petka, James; Depcik, Christopher; Peltier, Edward; Stagg-Williams, Susan

2015-01-01

Researchers across the globe are searching for energy sources to replace the petroleum-based fuels used by the transportation sector. A fuel of particular interest is biodiesel, produced from a diverse variety of feedstock oils with differing fuel properties that alter the operation and emissions of the engines using them. As biodiesel may be mixed with petroleum-based diesel, the fuel being used by a diesel engine may vary by both biodiesel blend percentage and source. Therefore, the influence of biodiesel properties as a function of blend is important to understand. In this study, four biodiesels, produced from palm, jatropha, soybean, and beef tallow, are tested with blends of petroleum diesel at ratios of 5%, 10%, 20%, and 50% biodiesel content. The results are compared with tests of neat diesel and each biodiesel. Using electronic injection, timing is modulated to normalize combustion phasing for all fuels tested to directly investigate the effects of biodiesel on combustion. Results indicate that fuel viscosity, energy content, and molecular structure have distinct influences on combustion that must be considered for engine calibration. When adjusted for combustion timing, biodiesel blends also showed a general decrease in NO x emissions compared to ultra-low sulfur diesel. - Highlights: • Biodiesel injection timing is adjusted to remove cetane number effect on combustion. • When combustion is normalized, biodiesel NO x emissions are lower than those of ULSD. • Four distinct biodiesels used in blends from 0% to 100% biodiesel/ULSD fraction. • Correlating fuel properties to combustion/emissions is useful for engine calibration

Application of bioethanol/RME/diesel blend in a Euro5 automotive diesel engine: Potentiality of closed loop combustion control technology

International Nuclear Information System (INIS)

Guido, Chiara; Beatrice, Carlo; Napolitano, Pierpaolo

2013-01-01

Highlights: ► Effects of a bioethanol/biodiesel/diesel blend on Euro5 diesel engine. ► Potentiality of combustion control technology with alternative fuels. ► Strong smoke and NOx emissions reduction. ► No power penalties burning bioethanol blend by means of combustion control activation. -- Abstract: The latest European regulations require the use of biofuels by at least 10% as energy source in transport by 2020. This goal could be reached by means of the use of different renewable fuels; bioethanol (BE) is one of the most interesting for its low production cost and availability. BE usually replaces gasoline in petrol engines but it can be also blended in low concentrations to feed diesel engines. In this paper the results of an experimental activity aimed to study the impact of a BE/biodiesel/mineral diesel blend on performance and emissions in a last generation automotive diesel engine are presented. The tests were performed in steady-state in eight partial load engine conditions and at 2500 rpm in full load. Two fuel blends have been compared: the Rapeseed Methyl Ester (RME)/diesel with 10% of biodiesel by volume (B10), and the BE/RME/diesel with 20% of BE and 10% of biodiesel by volume (E20B10). The experimental campaign was carried out on a 2.0 L diesel engine compliant with Euro5 regulation. The engine features the closed loop combustion control (CLCC), which enables individual and real-time control of injection phasing and cylinder inner torque by means of in-cylinder pressure sensors connected with the Electronic Control Unit (ECU). As expected, the results showed a strong smoke emissions reduction for E20B10 in all tested conditions, mainly due to the high oxygen content of BE. Also a reduction of NOx emissions were observed with BE addiction. The results confirm that the CLCC adoption enables a significant improvement in the robustness of the engine performance and emissions when blends with low heat content and very low cetane number (as BE

Combined effect of nanoemulsion and EGR on combustion and emission characteristics of neat lemongrass oil (LGO)-DEE-diesel blend fuelled diesel engine

International Nuclear Information System (INIS)

Sathiyamoorthi, R.; Sankaranarayanan, G.; Pitchandi, K.

2017-01-01

Highlights: • Neat lemongrass oil can be used as an alternate fuel in diesel engine. • The combined effect of nano emulsion and EGR using LGO25-DEE-Diesel is investigated. • The BTE is improved for nano emulsion fuel blend. • The NO_x and smoke emissions decrease significantly. • Cylinder pressure and Heat release rate increase with longer ignition delay. - Abstract: In the present experimental study, the combined effects of nanoemulsion and exhaust gas recirculation (EGR) on the performance, combustion and emission characteristics of a single cylinder, four stroke, variable compression ratio diesel engine fueled with neat lemongrass oil (LGO)-diesel-DEE (diethyl ether) blend are investigated. The Neat Lemongrass oil could be used as a new alternate fuel in compression ignition engines without any engine modifications. The entire investigation was conducted in the diesel engine using the following test fuels: emulsified LGO25, cerium oxide blended emulsified LGO25 and DEE added emulsified LGO25 with EGR respectively and compared with standard diesel and LGO25 (75% by volume of diesel and 25% by volume of lemongrass oil) fuels. The combined effect of DEE added nano-emulsified LGO25 with EGR yielded a significant reduction in NO_x and smoke emission by 30.72% and 11.2% respectively compared to LGO25. Furthermore, the HC and CO emissions were reduced by 18.18% and 33.31% respectively than with LGO25. The brake thermal efficiency and brake specific fuel consumption increased by 2.4% and 10.8% respectively than LGO25. The combustion characteristics such as cylinder pressure and heat release rate increased by 4.46% and 3.29% respectively than with LGO25. The combustion duration and ignition delay increase at nano-emulsified LGO25 with DEE and EGR mode but decrease for nano-emulsified LGO25 fuel.

The Influence of Hydrogen Gas on the Measures of Efficiency of Diesel Internal Combustion Engine

Directory of Open Access Journals (Sweden)

Jurgis Latakas

2014-12-01

Full Text Available In this research paper energy and ecological parameters of diesel engine which works under addition of hydrogen (10, 20, 30 l/ min are presented. A survey of research literature has shown that addition of hydrogen gases improve diesel combustion; increase indicated pressure; decrease concentration of carbon dioxide (CO2, hydrocarbons (HC, particles; decrease fuel consumptions. Results of the experiment revealed that hydrogen gas additive decreased pressure in cylinder in kinetic combustion phase. Concentration of CO2 and nitrous oxides (NOx decreased not significantly, HC – increased. Concentration of particles in engine exhaust gases significantly decreased. In case when hydrogen gas as additive was supplied, the fuel consumptions decreased a little. Using AVL BOOST software combustion process analysis was made. It was determined that in order to optimize engine work process under hydrogen additive usage, it is necessary to adjust diesel injection angle.

Fuel composition impact on heavy duty diesel engine combustion & emissions

NARCIS (Netherlands)

Frijters, P.J.M.

2012-01-01

The Heavy Duty Diesel or compression ignition (CI) engine plays an important economical role in societies all over the world. Although it is a fuel efficient internal combustion engine design, CI engine emissions are an important contributor to global pollution. To further reduce engine emissions

Combustion characteristics of a turbocharged DI compression ignition engine fueled wth petroleum diesel fuels and biodiesel

Energy Technology Data Exchange (ETDEWEB)

Canakci, M. [Kocaeli University, Izmit (Turkey). Department of Mechanical Education

2007-04-15

In this study, the combustion characteristics and emissions of two different petroleum diesel fuels (No. 1 and No. 2) and biodiesel from soybean oil were compared. The tests were performed at steady state conditions in a four-cylinder turbocharged DI diesel engine at full load at 1400-rpm engine speed. The experimental results compared with No. 2 diesel fuel showed that biodiesel provided significant reductions in PM, CO, and unburned HC, the NO{sub x} increased by 11.2%. Biodiesel had a 13.8% increase in brake-specific fuel consumption due to its lower heating value. However, using No. 1 diesel fuel gave better emission results, NO{sub x} and brake-specific fuel consumption reduced by 16.1% and 1.2%, respectively. The values of the principal combustion characteristics of the biodiesel were obtained between two petroleum diesel fuels. The results indicated that biodiesel may be blended with No. 1 diesel fuel to be used without any modification on the engine. (author)

Exhaust gas recirculation for advanced diesel combustion cycles

International Nuclear Information System (INIS)

Asad, Usman; Zheng, Ming

2014-01-01

Highlights: • Analysis of the incremental (cycle-by-cycle) build-up of EGR. • Proposed one-step equations for transient/steady-state gas concentration estimation. • Defined an in-cylinder excess-air ratio to account for the recycled oxygen with EGR. • Demonstrated the use of intake oxygen as a reliable measure of EGR effectiveness. • Demonstrated the impact of engine load and intake pressure on EGR effectiveness. - Abstract: Modern diesel engines tend to utilize significantly large quantities of exhaust gas recirculation (EGR) and high intake pressures across the engine load range to meet NOx targets. At such high EGR rates, the combustion process and exhaust emissions tend to exhibit a marked sensitivity to small changes in the EGR quantity, resulting in unintended deviations from the desired engine performance characteristics (energy efficiency, emissions, stability). An accurate estimation of EGR and its effect on the intake dilution are, therefore, necessary to enable its application during transient engine operation or unstable combustion regimes. In this research, a detailed analysis that includes estimation of the transient (cycle-by-cycle) build-up of EGR and the time (engine cycles) required to reach the steady-state EGR operation has been carried out. One-step global equations to calculate the transient and steady-state gas concentrations in the intake and exhaust are proposed. The effects of engine load and intake pressure on EGR have been examined and explained in terms of intake charge dilution and in-cylinder excess-air ratio. The EGR analysis is validated against a wide range of empirical data that include low temperature combustion cycles, intake pressure and load sweeps. This research intends to not only formulate a clear understanding of EGR application for advanced diesel combustion but also to set forth guidelines for transient analysis of EGR

Co-combustion of biodiesel with oxygenated fuels in direct injection diesel engine

Directory of Open Access Journals (Sweden)

Tutak Wojciech

2017-01-01

Full Text Available The paper presents results of experimental investigation of cocombustion process of biodiesel (B100 blended with oxygenated fuels with 20% in volume. As the alternative fuels ware used hydrated ethanol, methanol, 1-butanol and 2-propanol. It was investigated the influence of used blends on operating parameters of the test engine and exhaust emission (NOx, CO, THC, CO2. It is observed that used blends are characterized by different impact on engine output power and its efficiency. Using biodiesel/alcohol blend it is possible to improve engine efficiency with small drop in indicated mean effective pressure (IMEP. Due to combustion characteristic of biodiesel/alcohol obtained a slightly larger specific NOx emission. It was also observed some differences in combustion phases due to various values of latent heat of evaporation of used alcohols and various oxygen contents. Test results confirmed that the combustion process occurring in the diesel engine powered by blend takes place in a shorter time than in the typical diesel engine.

Analysis of pre-heated fuel combustion and heat-emission dynamics in a diesel engine

Science.gov (United States)

Plotnikov, S. A.; Kartashevich, A. N.; Buzikov, S. V.

2018-01-01

The article explores the feasibility of diesel fuel pre-heating. The research goal was to obtain and analyze the performance diagrams of a diesel engine fed with pre-heated fuel. The engine was tested in two modes: at rated RPMs and at maximum torque. To process the diagrams the authors used technique developed by the Central Diesel Research Institute (CDRI). The diesel engine’s heat emission curves were obtained. The authors concluded that fuel pre-heating shortened the initial phase of the combustion process and moderated the loads, thus making it possible to boost a diesel engine’s mean effective pressure.

The Mutagenic Potential Caused by the Emissions from Combustion of Crude Glycerin and Diesel Fuel

Directory of Open Access Journals (Sweden)

Daniel Terruggi Mazak

2015-04-01

Full Text Available This study evaluated the use of crude glycerin as an alternative of energy generation to replace the traditional fuels. The Tradescantia stamen hair mutation assay (Trad-SH was applied to study the mutagenic effects caused by the emissions generated in the direct combustion of diesel oil and glycerin in a flame tube furnace. Tradescantia inflorescences were exposed to gaseous emissions from the combustion tests in a fumigation chamber for 30-40 min. The analysis of variance and the Tukey test were applied to compare the differences between six test groups (intoxicated with emissions from glycerin and diesel oil combustion and a control group. Only one glycerin group showed statistical differences (0.05, possibly due to the complexity of the burning process and impurities, besides the acrolein present in its emissions. The high heating value (HHV of crude glycerin (25.5 MJ/kg was lower than diesel oil (45.19 MJ/kg, but it was comparable to other fuels. Although the use of glycerin as a biofuel could be an important aspect to be considered, the results showed that the glycerin had a substantial mutagenic potential similar to that of diesel oil.

Heavy-Duty Low-Temperature and Diesel Combustion & Heavy-Duty Combustion Modeling

Energy Technology Data Exchange (ETDEWEB)

Musculus, Mark P. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-11-01

Regulatory drivers and market demands for lower pollutant emissions, lower carbon dioxide emissions, and lower fuel consumption motivate the development of clean and fuel-efficient engine operating strategies. Most current production engines use a combination of both in-cylinder and exhaust emissions-control strategies to achieve these goals. The emissions and efficiency performance of in-cylinder strategies depend strongly on flow and mixing processes associated with fuel injection. Various diesel engine manufacturers have adopted close-coupled post-injection combustion strategies to both reduce pollutant emissions and to increase engine efficiency for heavy-duty applications, as well as for light- and medium-duty applications. Close-coupled post-injections are typically short injections that follow a larger main injection in the same cycle after a short dwell, such that the energy conversion efficiency of the post-injection is typical of diesel combustion. Of the various post-injection schedules that have been reported in the literature, effects on exhaust soot vary by roughly an order of magnitude in either direction of increasing or decreasing emissions relative to single injections (O’Connor et al., 2015). While several hypotheses have been offered in the literature to help explain these observations, no clear consensus has been established. For new engines to take full advantage of the benefits that post-injections can offer, the in-cylinder mechanisms that affect emissions and efficiency must be identified and described to provide guidance for engine design.

Soot temperature and KL factor for biodiesel and diesel spray combustion in a constant volume combustion chamber

KAUST Repository

Zhang, Ji; Jing, Wei; Roberts, William L.; Fang, Tiegang

2013-01-01

This paper presents measurements of the soot temperature and KL factor for biodiesel and diesel combustion in a constant volume chamber using a two-color technique. This technique uses a high-speed camera coupled with two narrowband filters (550. nm

Characterization of size, number, concentration and morphology of particulate matter emitted from a high performance diesel combustion system using biomass derived fuels

Energy Technology Data Exchange (ETDEWEB)

Bhardwaj, Om Parkash; Krishnamurthy, Ketan; Kremer, Florian; Pischinger, Stefan [RWTH Aachen Univ. (Germany). Inst. for Combustion Engines; Berg, Angelika von; Roth, Georg [RWTH Aachen Univ. (Germany). Inst. of Crystallography; Lueers, Bernhard; Kolbeck, Andreas; Koerfer, Thomas [FEV GmbH, Aachen (Germany)

2013-06-01

Motor vehicle emissions have been identified as a major source of particulates. Although the low limits of particulate matter cause a need for a particulate trap in most of the present day diesel engines, the physical and chemical characterization of particles with the measures of size, number, volatility and reactivity etc. is of increasing interest with respect to the regeneration frequency and regeneration efficiency of a particulate trap. Within the Cluster of Excellence ''Tailor-Made Fuels from Biomass (TMFB)'' at RWTH Aachen University, the Institute for Combustion Engines carried out a detailed investigation program to explore the potential of future biofuel candidates for future combustion systems. The experiments for particulate measurements and analysis were conducted on a EURO 6 compliant High Efficiency Diesel Combustion System (HECS) with petroleum based diesel fuel as reference and today's biofuel (i.e. FAME) as well as a potential future biomass derived fuel candidate (i.e. 2-MTHF I DBE), being developed under TMFB approach. Soot samples collected on polycarbonate filters were analyzed using SEM; revealing vital informations regarding particle size distribution. Furthermore, thermophoretic sampling was also performed on copper grids and samples were analyzed using TEM to determine its graphitic micro-structure. In addition, X-Ray diffraction (XRD) measurements were also performed to get further quantitative information regarding crystal lattice parameters and structure of investigated soot. The results indicate more than 90% reduction in the mass and number concentrations of engine out particle emissions using future biomass derived fuel candidate. A good co-relation was observed between TEM micro-structure results and quantitative crystal lattice and structure information obtained from XRD studies, indicating higher reactivity for soot emitted from 2-MTHF/DBE. (orig.)

Combustion performance and pollutant emissions analysis using diesel/gasoline/iso-butanol blends in a diesel engine

International Nuclear Information System (INIS)

Wei, Mingrui; Li, Song; Xiao, Helin; Guo, Guanlun

2017-01-01

Highlights: • The diesel/gasoline/iso-butanol blends were investigated in a CI engine. • Blend with gasoline or iso-butanol produce higher HC emission. • CO increase at low loads and decrease at medium and high loads with blend fuels. • Gasoline or iso-butanol decrease large particles but increase small particles. • Blend fuels reduce total PM number and mass concentrations. - Abstract: In this study, the effects of diesel/gasoline/iso-butanol blends, including pure diesel (D100), diesel (70%)/gasoline (30%) (D70G30, by mass), diesel (70%)/iso-butanol (30%) (D70B30) and diesel (70%)/gasoline (15%)/iso-butanol (15%) (D70G15B15), on combustion and exhaust pollutant emissions characteristics in a four-cylinder diesel engine were experimentally investigated under various engine load conditions with a constant speed of 1800 rpm. The results indicated that D70G30, D70G15B15 and D70B30 delayed the ignition timing and shortened the combustion duration compared to D100. Additionally, CA50 was retarded when engine fuelled with D70G30, D70G15B15 and D70B30 at low engine load conditions, but it was advanced at medium and high engine loads. The maximum pressure rise rates (MPRRs) of D70G30, D70G15B15 and D70B30 were increased compared with D100 except for at engine load of 0.13 MPa BMEP (brake mean effective pressure). Meanwhile, D70G15B15 and D70B30 produced higher brake specific fuel consumption (BSFC) than that of D100. The effects of diesel blend with gasoline or iso-butanol on exhaust pollutant emissions were varied with loads. CO emissions were increased obviously and NOx emissions were decreased under low engine loads. However, CO emissions were decreased and NOx emissions were slightly increased under the medium and high engine load conditions. However, D70G30, D70G15B15 and D70B30 leaded to higher HC emissions than D100 regardless the variation of engine load. Moreover, the particulate matter (PM) (diameter, number and mass concentrations) emissions by using

Study on homogeneous charge diesel combustion engine. 4th Report. Search for low emission combustion method with diesel fuel pre-mixture; Kin`itsu kongo asshuku chakka diesel kikan ni kansuru kenkyu. 4. Keiyu yokongoka deno tei emission no kanosei

Energy Technology Data Exchange (ETDEWEB)

Suzuki, H; Koike, S; Odaka, M [Traffic Safety and Nuisance Research Inst., Tokyo (Japan)

1997-10-01

Single fuel operation with diesel fuel has been tried experimentally for the Homogeneous Charge Diesel Combustion method (HCDC). The higher the pre-mixed fuel ratio, the lower the emissions. But diesel knock due to early self ignition may be occurred under high pre-mixed fuel ratio conditions and consequently the maximum pre-mixed fuel ratio is restricted by these knock limits. Full load operations with higher pre-mixed fuel ratio can be possible with a supercharging which improve the knock limits and emissions. 8 refs., 12 figs.

Experimental study on fuel economies and emissions of direct-injection premixed combustion engine fueled with gasoline/diesel blends

International Nuclear Information System (INIS)

Du, Jiakun; Sun, Wanchen; Guo, Liang; Xiao, Senlin; Tan, Manzhi; Li, Guoliang; Fan, Luyan

2015-01-01

Highlights: • A compound combustion concept was proposed and investigated. • Premixed combustion near the top dead center was investigated using blended fuels. • Increasing gasoline blend ratio was found to enhance the mixture preparation. • Too much addition of gasoline decreases indicated thermal efficiency. • Gasoline/diesel blends may be a promising alternative for premixed combustion. - Abstract: The effects of gasoline/diesel blended fuel composed of diesel fuel with gasoline as additives in volume basis, on combustion, fuel economies and exhaust emissions were experimentally investigated. Tests were carried out based on a turbocharged Common-rail Direct Injection engine at a constant engine speed of 1800 r/min and different loads of 3.2 bar, 5.1 bar Indicated Mean Effective Pressure. Additionally, the effect of combustion phasing and Exhaust Gas Recirculation were evaluated experimentally for various fuels. The results indicated that with the fraction of gasoline increasing in blends, the ignition delay was prolonged and the combustion phasing was retarded with the common injection timing. This led to a significant increase of premixed burning phase, which was in favor of smoke reduction; although, too much gasoline might be adverse to fuel consumption. An optimum combustion phasing was identified, leading to a higher thermal efficiency and better premixed combustion with blended fuels. A combined application of Exhaust Gas Recirculation and blended fuel with a high gasoline fraction was confirmed effective in reducing the oxides of nitrogen and smoke emissions simultaneously at the optimum combustion phasing without giving significant penalty of fuel consumption. A compound combustion mode with its emission lower than the conventional Compression Ignition engines, and efficiency higher than the typical Spark Ignition engines, could be achieved with a cooperative control of Exhaust Gas Recirculation and combustion phasing of the gasoline/diesel

Modeling the effects of auxiliary gas injection and fuel injection rate shape on diesel engine combustion and emissions

Science.gov (United States)

Mather, Daniel Kelly

1998-11-01

The effect of auxiliary gas injection and fuel injection rate-shaping on diesel engine combustion and emissions was studied using KIVA a multidimensional computational fluid dynamics code. Auxiliary gas injection (AGI) is the injection of a gas, in addition to the fuel injection, directly into the combustion chamber of a diesel engine. The objective of AGI is to influence the diesel combustion via mixing to reduce emissions of pollutants (soot and NO x). In this study, the accuracy of modeling high speed gas jets on very coarse computational grids was addressed. KIVA was found to inaccurately resolve the jet flows near walls. The cause of this inaccuracy was traced to the RNG k - ɛ turbulence model with the law-of-the-wall boundary condition used by KIVA. By prescribing the lengthscale near the nozzle exit, excellent agreement between computed and theoretical jet penetration was attained for a transient gas jet into a quiescent chamber at various operating conditions. The effect of AGI on diesel engine combustion and emissions was studied by incorporating the coarse grid gas jet model into a detailed multidimensional simulation of a Caterpillar 3401 heavy-duty diesel engine. The effects of AGI timing, composition, amount, orientation, and location were investigated. The effects of AGI and split fuel injection were also investigated. AGI was found to be effective at reducing soot emissions by increasing mixing within the combustion chamber. AGI of inert gas was found to be effective at reducing emissions of NOx by depressing the peak combustion temperatures. Finally, comparison of AGI simulations with experiments were conducted for a TACOM-LABECO engine. The results showed that AGI improved soot oxidation throughout the engine cycle. Simulation of fuel injection rate-shaping investigated the effects of three injection velocity profiles typical of unit-injector type, high-pressure common-rail type, and accumulator-type fuel injectors in the Caterpillar 3401 heavy

Functional Group Analysis for Diesel-like Mixing-Controlled Compression Ignition Combustion Blendstocks

Energy Technology Data Exchange (ETDEWEB)

Gaspar, Daniel J.; McCormick, Robert L.; Polikarpov, Evgueni; Fioroni, Gina; George, Anthe; Albrecht, Karl O.

2016-12-30

This report addresses the suitability of hydrocarbon and oxygenate functional groups for use as a diesel-like fuel blending component in an advanced, mixing-controlled, compression ignition combustion engine. The functional groups are chosen from those that could be derived from a biomass feedstock, and represent a full range of chemistries. This first systematic analysis of functional groups will be of value to all who are pursuing new bio-blendstocks for diesel-like fuels.

A computational investigation of diesel and biodiesel combustion and NOx formation in a light-duty compression ignition engine

Energy Technology Data Exchange (ETDEWEB)

Wang, Zihan [Mississippi State Univ., Mississippi State, MS (United States). Dept. of Mechanical Engineering; Srinivasan, Kalyan K. [Mississippi State Univ., Mississippi State, MS (United States). Dept. of Mechanical Engineering; Krishnan, Sundar R. [Mississippi State Univ., Mississippi State, MS (United States). Dept. of Mechanical Engineering; Som, Sibendu [Argonne National Lab. (ANL), Argonne, IL (United States). Center for Transportation Research

2012-04-24

Diesel and biodiesel combustion in a multi-cylinder light duty diesel engine were simulated during a closed cycle (from IVC to EVO), using a commercial computational fluid dynamics (CFD) code, CONVERGE, coupled with detailed chemical kinetics. The computational domain was constructed based on engine geometry and compression ratio measurements. A skeletal n-heptane-based diesel mechanism developed by researchers at Chalmers University of Technology and a reduced biodiesel mechanism derived and validated by Luo and co-workers were applied to model the combustion chemistry. The biodiesel mechanism contains 89 species and 364 reactions and uses methyl decanoate, methyl-9- decenoate, and n-heptane as the surrogate fuel mixture. The Kelvin-Helmholtz and Rayleigh-Taylor (KH-RT) spray breakup model for diesel and biodiesel was calibrated to account for the differences in physical properties of the fuels which result in variations in atomization and spray development characteristics. The simulations were able to capture the experimentally observed pressure and apparent heat release rate trends for both the fuels over a range of engine loads (BMEPs from 2.5 to 10 bar) and fuel injection timings (from 0° BTDC to 10° BTDC), thus validating the overall modeling approach as well as the chemical kinetic models of diesel and biodiesel surrogates. Moreover, quantitative NOx predictions for diesel combustion and qualitative NOx predictions for biodiesel combustion were obtained with the CFD simulations and the in-cylinder temperature trends were correlated to the NOx trends.

Combustion characteristics and optimal factors determination with Taguchi method for diesel engines port-injecting hydrogen

International Nuclear Information System (INIS)

Wu, Horng-Wen; Wu, Zhan-Yi

2012-01-01

This study applies the L 9 orthogonal array of the Taguchi method to find out the best hydrogen injection timing, hydrogen-energy-share ratio, and the percentage of exhaust gas circulation (EGR) in a single DI diesel engine. The injection timing is controlled by an electronic control unit (ECU) and the quantity of hydrogen is controlled by hydrogen flow controller. For various engine loads, the authors determine the optimal operating factors for low BSFC (brake specific fuel consumption), NO X , and smoke. Moreover, net heat-release rate involving variable specific heat ratio is computed from the experimental in-cylinder pressure. In-cylinder pressure, net heat-release rate, A/F ratios, COV (coefficient of variations) of IMEP (indicated mean effective pressure), NO X , and smoke using the optimum condition factors are compared with those by original baseline diesel engine. The predictions made using Taguchi's parameter design technique agreed with the confirmation results on 95% confidence interval. At 45% and 60% loads the optimum factor combination compared with the original baseline diesel engine reduces 14.52% for BSFC, 60.5% for NO X and for 42.28% smoke and improves combustion performance such as peak in-cylinder pressure and net heat-release rate. Adding hydrogen and EGR would not generate unstable combustion due to lower COV of IMEP. -- Highlights: ► We use hydrogen injector controlled by ECU and cooled EGR system in a diesel engine. ► Optimal factors by Taguchi method are determined for low BSFC, NO X and smoke. ► The COV of IMEP is lower than 10% so it will not cause the unstable combustion. ► We improve A/F ratio, in-cylinder pressure, and heat-release at optimized engine. ► Decrease is 14.5% for BSFC, 60.5% for NO X , and 42.28% for smoke at optimized engine.

Narrow band flame emission from dieseline and diesel spray combustion in a constant volume combustion chamber

KAUST Repository

Wu, Zengyang

2016-08-18

In this paper, spray combustion of diesel (No. 2) and diesel-gasoline blend (dieseline: 80% diesel and 20% gasoline by volume) were investigated in an optically accessible constant volume combustion chamber. Effects of ambient conditions on flame emissions were studied. Ambient oxygen concentration was varied from 12% to 21% and three ambient temperatures were selected: 800 K, 1000 K and 1200 K. An intensified CCD camera coupled with bandpass filters was employed to capture the quasi-steady state flame emissions at 430 nm and 470 nm bands. Under non-sooting conditions, the narrow-band flame emissions at 430 nm and 470 nm can be used as indicators of CH∗ (methylidyne) and HCHO∗ (formaldehyde), respectively. The lift-off length was measured by imaging the OH∗ chemiluminescence at 310 nm. Flame emission structure and intensity distribution were compared between dieseline and diesel at wavelength bands. Flame emission images show that both narrow band emissions become shorter, thinner and stronger with higher oxygen concentration and higher ambient temperature for both fuels. Areas of weak intensity are observed at the flame periphery and the upstream for both fuels under all ambient conditions. Average flame emission intensity and area were calculated for 430 nm and 470 nm narrow-band emissions. At a lower ambient temperature the average intensity increases with increasing ambient oxygen concentration. However, at the 1200 K ambient temperature condition, the average intensity is not increasing monotonically for both fuels. For most of the conditions, diesel has a stronger average flame emission intensity than dieseline for the 430 nm band, and similar phenomena can be observed for the 470 nm band with 800 K and 1200 K ambient temperatures. However, for the 1000 K ambient temperature cases, dieseline has stronger average flame emission intensities than diesel for all oxygen concentrations at 470 nm band. Flame emissions for the two bands have a

Evaluation of economic and technical efficiency of diesel engines operation on the basis of volume combustion rate

Directory of Open Access Journals (Sweden)

І. О. Берестовой

2016-11-01

Full Text Available The article deals with a new approach to evaluation of complex efficiency of diesel engines. Traditionally, cylinder’s capacity, rotation frequency, average efficient pressure inside cylinder, piston’s stroke, average piston’s velocity, fuel specific consumption and other indices are used as generalizing criteria, characterizing diesel engine’s efficiency, but they do not reflect interrelation between engine’s complex efficiency and a set of economic, mass-dimensional, operational and ecological efficiency. The approach applied in the article makes it possible to reveal the existing and modify the existing methods of solving the problem of improving diesel engine’s efficiency with due regard to interrelation of the parameters, characterizing efficiency of their operation. Statistic analyses were carried out, on the basis of which an assumption regarding the existence of interrelation between specific fuel consumption and the analyzed engine’s parameters was made. Processing of statistical data for various analyzed functions of diesel engines helped offer a function, illustrating the link between volume combustion rate, piston’s area and nominal theoretical specific fuel consumption. Interrelation between volume combustion rate, nominal parameters of diesel operation and efficiency indices, obtained by processing statistical data of more than 500 models of diesels of different series was evaluated, the main feature of it being a mathematical trend. The analysis of the obtained function makes it possible to establish an interrelation between economic efficiency of a diesel, its main index being specific fuel consumption and volume combustion rate and design peculiarities

Experimental investigation on regulated and unregulated emissions of a diesel/methanol compound combustion engine with and without diesel oxidation catalyst.

Science.gov (United States)

Zhang, Z H; Cheung, C S; Chan, T L; Yao, C D

2010-01-15

The use of methanol in combination with diesel fuel is an effective measure to reduce particulate matter (PM) and nitrogen oxides (NOx) emissions from in-use diesel vehicles. In this study, a diesel/methanol compound combustion (DMCC) scheme was proposed and a 4-cylinder naturally-aspirated direct-injection diesel engine modified to operate on the proposed combustion scheme. The effect of DMCC and diesel oxidation catalyst (DOC) on the regulated emissions of total hydrocarbons (THC), carbon monoxide (CO), NOx and PM was investigated based on the Japanese 13 Mode test cycle. Certain unregulated emissions, including methane, ethyne, ethene, 1,3-butadiene, BTX (benzene, toluene, xylene), unburned methanol and formaldehyde were also evaluated based on the same test cycle. In addition, the soluble organic fraction (SOF) in the particulate and the particulate number concentration and size distribution were investigated at certain selected modes of operation. The results show that the DMCC scheme can effectively reduce NOx, particulate mass and number concentrations, ethyne, ethene and 1,3-butadiene emissions but significantly increase the emissions of THC, CO, NO(2), BTX, unburned methanol, formaldehyde, and the proportion of SOF in the particles. After the DOC, the emission of THC, CO, NO(2), as well as the unregulated gaseous emissions, can be significantly reduced when the exhaust gas temperature is sufficiently high while the particulate mass concentration is further reduced due to oxidation of the SOF. Copyright 2009 Elsevier B.V. All rights reserved.

Experimental studies on the combustion characteristics and performance of a direct injection engine fueled with biodiesel/diesel blends

International Nuclear Information System (INIS)

Qi, D.H.; Chen, H.; Geng, L.M.; Bian, Y. ZH.

2010-01-01

Biodiesel is an alternative diesel fuel that can be produced from different kinds of vegetable oils. It is an oxygenated, non-toxic, sulphur-free, biodegradable, and renewable fuel and can be used in diesel engines without significant modification. However, the performance, emissions and combustion characteristics will be different for the same biodiesel used in different types of engine. In this study, the biodiesel produced from soybean crude oil was prepared by a method of alkaline-catalyzed transesterification. The effects of biodiesel addition to diesel fuel on the performance, emissions and combustion characteristics of a naturally aspirated DI compression ignition engine were examined. Biodiesel has different properties from diesel fuel. A minor increase in brake specific fuel consumption (BSFC) and decrease in brake thermal efficiency (BTE) for biodiesel and its blends were observed compared with diesel fuel. The significant improvement in reduction of carbon monoxide (CO) and smoke were found for biodiesel and its blends at high engine loads. Hydrocarbon (HC) had no evident variation for all tested fuels. Nitrogen oxides (NOx) were slightly higher for biodiesel and its blends. Biodiesel and its blends exhibited similar combustion stages to diesel fuel. The use of transesterified soybean crude oil can be partially substituted for the diesel fuel at most operating conditions in terms of the performance parameters and emissions without any engine modification.

The role of the fuel injection system for combustion process optimization of highly turbocharged PC diesel engines; Die Rolle des Einspritzsystems bei der Brennverfahrensoptimierung von hochaufgeladenen Pkw-Dieselmotoren

Energy Technology Data Exchange (ETDEWEB)

Gerhardt, Juergen; Leonhard, Rolf; Krueger, Michael; Naber, Dirk; Pitt, J. [Robert Bosch GmbH, Stuttgart (Germany)

2008-07-01

In order to comply with continuously rising requirements from emission legislation and fuel economy enhancement, modern Diesel engines for passenger cars still offer a variety of measures. Focus of this paper is the importance of a highly flexible fuel-injection system and an optimized injection strategy as direct measures to improve both, tail-pipe emission as well as vehicle fuel economy. An integrated system approach of high pressure pump, injector and nozzle provides the latest injection patterns combined with an increased rail pressure level with a best-in-class hydraulic efficiency. The resulting improvement in the injection system and thus in the combustion also enables the introduction of additional indirect, very effective measures for fuel consumption reduction, such as downsizing and downspeeding. In order to fully utilize the potent of the mentioned approaches, the application of advanced boosting technology is an additional key factor. Bosch Diesel injection technology and optimized combustion systems pave the way to achieve the goal of efficient emission reduction. (orig.)

Experimental study on combustion and emission characteristics of a diesel engine fueled with 2,5-dimethylfuran–diesel, n-butanol–diesel and gasoline–diesel blends

International Nuclear Information System (INIS)

Chen, Guisheng; Shen, Yinggang; Zhang, Quanchang; Yao, Mingfa; Zheng, Zunqing; Liu, Haifeng

2013-01-01

In the paper, combustion and emissions of a multi-cylinder CI (compression-ignition) engine fueled with DMF–diesel, n-butanol–diesel and gasoline–diesel blends were experimentally investigated, and fuel characteristics of DMF, n-butanol and gasoline were compared. Diesel was used as the base fuel. And 30% of DMF, n-butanol and gasoline were blended with the base fuel by volume respectively, referred to as D30, B30 and G30. Results show that compared to B30 and G30, D30 has longer ignition delay because of lower cetane number, which leads to faster burning rate and higher pressure rise rate. With increasing EGR (exhaust gas recirculation) rate, D30 gets the lowest soot emissions, and extended ignition delay and fuel oxygen are two key factors reducing soot emissions, and ignition delay has greater effects than fuel oxygen on soot reduction. In addition, D30 and B30 improve the trade-off of NO x -soot remarkably and extend low-emission region without deteriorating fuel efficiency by utilizing medium EGR rates ( x , THC and CO emissions and BSFC, but reduce soot greatly. • Fuel oxygen is more efficient than air oxygen while ignition delay has greater effects than fuel oxygen to reduce soot. • As diesel additive, DMF is superior to n-butanol and gasoline for reducing soot emissions. • Using DMF–diesel blends combined with medium EGR may be a better way to meet future emission standards

A Mixing Based Model for DME Combustion in Diesel Engines

DEFF Research Database (Denmark)

Bek, Bjarne H.; Sorenson, Spencer C.

1998-01-01

A series of studies has been conducted investigating the behavior of di-methyl ether (DME) fuel jets injected into quiescent combus-tion chambers. These studies have shown that it is possible to make a good estimate of the penetration of the jet based on existing correlations for diesel fuel......, by using appropriate fuel properties. The results of the spray studies have been incorporated into a first generation model for DME combustion. The model is entirely based on physical mixing, where chemical processes have been assumed to be very fast in relation to mixing. The assumption was made...

A mixing based model for DME combustion in diesel engines

DEFF Research Database (Denmark)

Bek, Bjarne Hjort; Sorenson, Spencer C

2001-01-01

A series of studies has been conducted investigating the behavior of di-methyl ether (DME) fuel jets injected into quiescent combustion chambers. These studies have shown that it is possible to make a good estimate of the penetration of the jet based on existing correlations for diesel fuel......, by using appropriate fuel properties. The results of the spray studies have been incorporated into a first generation model for DME combustion. The model is entirely based on physical mixing, where chemical processes have been assumed to be very fast in relation to mixing. The assumption was made...

El biodiesel de aceite de higuerilla como combustible alternativo para motores diesel

Directory of Open Access Journals (Sweden)

ALIRIO BENAVIDES

2007-01-01

Full Text Available En este artículo se presenta un estudio experimental sobre la producción y utilización del biodiesel de aceite de higuerilla. El máximo rendimiento de metilésteres en la reacción de transesterificación del aceite de higuerilla usado se obtiene bajo las siguientes condiciones: temperatura ambiente, una relación molar metanol/aceite de 9 y una concentración de catalizador de 0.8%. El biodiesel de aceite de higuerilla puede ser mezclado con el combustible diesel convencional derivado del petróleo en proporciones hasta del 15%, sin que la mezcla resultante se salga de las especificaciones de calidad estipuladas en los estándares nacionales e internacionales para combustibles diesel. La mayor dificultad para el uso del biodiesel de aceite de higuerilla en motores es su alta viscosidad. Sin embargo este biocombustible presenta excelentes propiedades de flujo a baja temperatura (valores bajos para los puntos de nube y fluidez. Las pruebas en motor con mezclas biodiesel de higuerilla/diesel convencional, en el rango de proporciones de biodiesel ensayadas, muestran que ha medida que se incrementa la proporción de biodiesel en la mezcla aumenta el consumo específico de combustible, disminuye el dosado relativo, la opacidad de humos se disminuye levemente, mientras que el rendimiento efectivo y las emisiones de CO y CO2 prácticamente permanecen constantes

Studies on the influence of combustion bowl modification for the operation of Cymbopogon flexuosus biofuel based diesel blends in a DI diesel engine

International Nuclear Information System (INIS)

Dhinesh, B.; Annamalai, M.; Lalvani, Isaac JoshuaRamesh; Annamalai, K.

2017-01-01

Highlights: • A novel biofuel, Cymbopogon flexuosus is used as an alternative energy source. • C20-D80 + 20 ppm profile stayed close to diesel fuel with BB. • Three different combustion bowl CB1, CB2, and CB3 were considered. • Resulting in higher thermal efficiency and lower HC, CO, emission. • Reduction of oxides of nitrogen and smoke emission for C20-D80 + 20 ppm and CB2. - Abstract: The aim of this experimental work is to figure out the optimized the combustion bowl geometry on a constant speed diesel engine for its efficient functioning with a novel biofuel. The novel biofuel considered for this research work was Cymbopogon flexuosus biofuel. To improve the performance level, 20% Cymbopogon flexuosus biofuel was blended with 80% of diesel fuel (C20-D80) and to further reduce the emission magnitude, 20 ppm of cerium oxide was added to the blended fuel (C20-D80 + 20 ppm). For this study four different combustion bowls were designed based on the keen literature survey. They were hemispherical combustion bowl (BB), shallow depth re-entrant combustion bowl (CB1), Toroidal re-entrant combustion bowl (CB2), Toroidal combustion bowl (CB3). Based on the experimental evaluation, the results have been discussed for low load and full load conditions for better understanding. Regarding the fuel modification, C20-D80 + 20 ppm resulted in better engine characteristics owing to combined effect of the oxygen molecule bearing fuel and superior thermal stability and activation energy of the cerium oxide nanoparticle. Of the various bowls considered for the tests, the combustion bowl CB2 showed superior performance and emission reduction compared with its competitors CB1, CB2, and BB. It could have ascribed to the better mixing rate, gain of swirl velocity and the turbulence level of the bowl. CB2 resulted in higher BTE and lower BSEC of 4.1% and 12.02% in low and full load conditions for C20-D80 + 20 ppm. Emission reduction observed was 17% of HC, 43.66% of CO and

Sound quality assessment of Diesel combustion noise using in-cylinder pressure components

Science.gov (United States)

Payri, F.; Broatch, A.; Margot, X.; Monelletta, L.

2009-01-01

The combustion process in direct injection (DI) Diesel engines is an important source of noise, and it is thus the main reason why end-users could be reluctant to drive vehicles powered with this type of engine. This means that the great potential of Diesel engines for environment preservation—due to their lower consumption and the subsequent reduction of CO2 emissions—may be lost. Moreover, the advanced combustion concepts—e.g. the HCCI (homogeneous charge compression ignition)—developed to comply with forthcoming emissions legislation, while maintaining the efficiency of current engines, are expected to be noisier because they are characterized by a higher amount of premixed combustion. For this reason many efforts have been dedicated by car manufacturers in recent years to reduce the overall level and improve the sound quality of engine noise. Evaluation procedures are required, both for noise levels and sound quality, that may be integrated in the global engine development process in a timely and cost-effective manner. In previous published work, the authors proposed a novel method for the assessment of engine noise level. A similar procedure is applied in this paper to demonstrate the suitability of combustion indicators for the evaluation of engine noise quality. These indicators, which are representative of the peak velocity of fuel burning and the resonance in the combustion chamber, are well correlated with the combustion noise mark obtained from jury testing. Quite good accuracy in the prediction of the engine noise quality has been obtained with the definition of a two-component regression, which also permits the identification of the combustion process features related to the resulting noise quality, so that corrective actions may be proposed.

Combustion stratification for naphtha from CI combustion to PPC

NARCIS (Netherlands)

Vallinayagam, R.; Vedharaj, S.; An, Y.; Dawood, A.; Izadi Najafabadi, M.; Somers, L.M.T.; Johansson, B.H.

2017-01-01

This study demonstrated the change in combustion homogeneity from conventional diesel combustion via partially premixed combustion towards HCCI. Experiments are performed in an optical diesel engine at a speed of 1200 rpm with diesel fuel. Single injection strategy is employed and the fuel is

Environmental effects of using Methanol as a biofuel into the combustion chamber of a heavy-duty diesel engine

Directory of Open Access Journals (Sweden)

kianoosh shojae

2016-12-01

Full Text Available Methanol as a biofuel is an environmentally friendly substitute for pure diesel and can be obtained from biomasses. The use of biofuels such as methanol for the combustion process is associated with positive impacts on the environment. Using pure methanol or a blend of diesel/methanol fuel in motorized vehicles has been proposed by researchers. In this paper, pure methanol was injected into the combustion chamber of a ISM 370 HD diesel engine and the exhaust emissions were evaluated by using AVL FIRE CFD code software at four engine speeds (1200, 1400, 1600 and 1800 rpm. Additionally, the influences of EGR mass fraction and various injection timings were investigated. In order to validate the simulation results, in-cylinder mean pressure and rate of heat release (RHR were compared with experimental data, and the results gave an acceptable agreement. The obtained results from the conducted simulation showed that the use of methanol fuel in the combustion chamber dramatically reduced the amount of exhaust emissions such as NO, soot, CO, and CO2 to 90%, 75%, 40%, and 26%, respectively. In addition, a mass fraction of EGR (20% caused a reduction in the amount of exhaust NO to about 12%. It was determined that when a system is equipped with a fueling system at 3 deg before top dead center (BTDC, the exhaust NO and soot are reduced by 5.8% and 3%.

Theoretical modeling of combustion characteristics and performance parameters of biodiesel in DI diesel engine with variable compression ratio

Energy Technology Data Exchange (ETDEWEB)

Al-Dawody, Mohamed F.; Bhatti, S.K. [Department of Mechanical Engineering, Andhra University (India)

2013-07-01

Increasing of costly and depleting fossil fuels are prompting researchers to use edible as well as non-edible vegetable oils as a promising alternative to petro-diesel fuels. A comprehensive computer code using ''Quick basic'' language was developed for the diesel engine cycle to study the combustion and performance characteristics of a single cylinder, four stroke, direct injection diesel engine with variable compression ratio. The engine operates on diesel fuel and 20% (mass basis) of biodiesel (derived from soybean oil) blended with diesel. Combustion characteristics such as cylinder pressure, heat release fraction, heat transfer and performance characteristics such as brake power; and brake specific fuel consumption (BSFC) were analyzed. On the basis of the first law of thermodynamics the properties at each degree crank angle was calculated. Wiebe function is used to calculate the instantaneous heat release rate. The computed results are validated through the results obtained in the simulation Diesel-rk software.

Simulation of biodiesel combustion in a light-duty diesel engine using integrated compact biodiesel–diesel reaction mechanism

DEFF Research Database (Denmark)

Ng, Hoon Kiat; Gan, Suyin; Ng, Jo-Han

2013-01-01

This computational fluid dynamics (CFD) study is performed to investigate the combustion characteristics and emissions formation processes of biodiesel fuels in a light-duty diesel engine. A compact reaction mechanism with 80 species and 303 reactions is used to account for the effects of chemical...... kinetics. Here, the mechanism is capable of emulating biodiesel–diesel mixture of different blending levels and biodiesel produced from different feedstock. The integrated CFD-kinetic model was validated against a test matrix which covers the entire saturated–unsaturated methyl ester range typical...... of biodiesel fuels, as well as the biodiesel–diesel blending levels. The simulated cases were then validated for in-cylinder pressure profiles and peak pressure values/timings. Errors in the peak pressure values did not exceed 1%, while the variations in peak pressure timings were kept within 1.5 crank angle...

Experimental Investigation Of Biogas-Biodiesel Dual Fuel Combustion In A Diesel Engine

Directory of Open Access Journals (Sweden)

Ramesha D. K.

2015-06-01

Full Text Available This study is an attempt at achieving diesel fuel equivalent performance from diesel engines with maximum substitution of diesel with renewable fuels. In this context the study has been designed to analyze the influence of B20 algae biodiesel as a pilot fuel in a biodiesel biogas dual fuel engine, and results are compared to those of biodiesel and diesel operation at identical engine settings. Experiments were performed at various loads from 0 to 100 % of maximum load at a constant speed of 1500 rpm. In general, B20 algae biodiesel is compatible with diesel in terms of performance and combustion characteristics. Dual fuel mode operation displays lower thermal efficiency and higher fuel consumption than for other fuel modes of the test run across the range of engine loads. Dual fuel mode displayed lower emissions of NOx and Smoke opacity while HC and CO concentrations were considerably higher as compared to other fuels. In dual fuel mode peak pressure and heat release rate were slightly higher compared to diesel and biodiesel mode of operation for all engine loads.

Fuel supply system for diesel engines. Kraftstoffzufuhrsystem fuer Dieselmotoren

Energy Technology Data Exchange (ETDEWEB)

Mowbray, D F; Jarrett, B A

1979-10-05

The invention deals with a fuel feeding system, in particular for diesel engines with direct injection, provided with electromagnetic fuel pumps and injection nozzles for every combustion chamber. The pumps are equiped with control systems, which are actuated during the injection process. Switch valves with magnetic control devices serve as controllers.

RESULTS OF THE DIESEL COMBUSTION CHAMBER OPTIMIZED DESIGN IN THE MULTICRITERIAL TASK ENVIRONMENT

Directory of Open Access Journals (Sweden)

A. Wrublewski

2015-12-01

Full Text Available The results of optimized designing of the higi-speed vehicle diesel engine combustion chamber based on application of the method of parameters space investingation are given. The optimal form of the combustion chamber and the direction of fuel jets at adjusted pressure rate and other functional resrictions are determined according to three criteria of quality – fuel consumption, hard particles and nitric oxide emissions.

Effects of Fuel Quantity on Soot Formation Process for Biomass-Based Renewable Diesel Fuel Combustion

KAUST Repository

Jing, Wei

2016-12-01

Soot formation process was investigated for biomass-based renewable diesel fuel, such as biomass to liquid (BTL), and conventional diesel combustion under varied fuel quantities injected into a constant volume combustion chamber. Soot measurement was implemented by two-color pyrometry under quiescent type diesel engine conditions (1000 K and 21% O2 concentration). Different fuel quantities, which correspond to different injection widths from 0.5 ms to 2 ms under constant injection pressure (1000 bar), were used to simulate different loads in engines. For a given fuel, soot temperature and KL factor show a different trend at initial stage for different fuel quantities, where a higher soot temperature can be found in a small fuel quantity case but a higher KL factor is observed in a large fuel quantity case generally. Another difference occurs at the end of combustion due to the termination of fuel injection. Additionally, BTL flame has a lower soot temperature, especially under a larger fuel quantity (2 ms injection width). Meanwhile, average soot level is lower for BTL flame, especially under a lower fuel quantity (0.5 ms injection width). BTL shows an overall low sooting behavior with low soot temperature compared to diesel, however, trade-off between soot level and soot temperature needs to be carefully selected when different loads are used.

The role of nozzle convergence in diesel combustion

Energy Technology Data Exchange (ETDEWEB)

J. Benajes; S. Molina; C. Gonzaalez; R. Donde [CMT-Motores Termicos, Universidad Politecnica de Valencia, Valencia (Spain)

2008-08-15

An experimental study has been performed for identifying the role of injector nozzle hole convergence and cavitation in diesel engine combustion and pollutant emissions. For doing so, five nozzles were tested under different operating and experimental conditions. The critical cavitation number of each nozzle was analyzed. With this value, an estimation of the mixing process at different conditions obtained. This data is used to explain the combustion results which are analyzed in terms of the apparent combustion time, rate of heat release, in-cylinder pressures, adiabatic temperatures and soot and NOx emissions. Special emphasis is put in developing an expression to explicitly link the mixing process and the injection rate with the rate of heat release. The results show that the fuel-air mixing process can be improved by the use of both convergent and cavitating nozzles, thus lowering the soot emissions. The NOx production, being dependent of the injection rate and the mixing process, does not necessarily increase with the use of more convergent nozzles. 40 refs., 8 fig., tabs.

Utilisation of VOC in Diesel Engines. Ignition and combustion of VOC released in crude oil tankers

International Nuclear Information System (INIS)

Melhus, Oeyvin

2002-01-01

The emission of VOC (Volatile Organic Compound) is a significant source of hydrocarbon pollution. In Norway, the offshore oil industry represents a major source. This emission represents both an energy loss and an environmental problem. Gas tankers have used boil-off gas from the cargo tanks as fuel for some time. However, for the current VOC project a new fuel injection concept is designed for tankers to take advantage of the energy present in the VOC evaporated from crude oil. The VOC is mixed with inert gas in these tankers, and thus the utilisation of this gas represents new challenges. The VOC project uses the concept of ''Condensate Diesel Process'' with pilot ignition. An experimental study of ignition and combustion of VOC Fuels reported here was initiated by the time it was decided to start a pilot project converting propulsion engines in shuttle tankers to use VOC Fuel. It is an experimental study carried out at the Marine Technology Centre (MTS). The objective was to study ignition and combustion of the chosen process in comparison with an ordinary diesel process. The experimental results have been discussed and compared with theoretical considerations of injection, ignition and combustion. For experiments on combustion, a rapid compression machine ''DyFo'' was redesigned to use VOC Fuel. The DyFo test rig was initially designed to study ignition and early combustion of spark ignited homogeneous gas/air charges. To study the ignition and early combustion of VOC Fuel injected at high pressure and ignited by pilot diesel fuel, a redesign was necessary. An important feature of the DyFo, is the visualisation of the combustion. The advantage of the DyFo test rig over an engine, is its simplicity and controllability. In an engine the visualisation would suffer from combustion deposits disturbing the view through the quartz glasses, making the images more difficult to interpret. The simplicity is on the other side a drawback. Correct thermal conditions inside

A comparative analysis on combustion and emissions of some next generation higher-alcohol/diesel blends in a direct-injection diesel engine

International Nuclear Information System (INIS)

Rajesh Kumar, B.; Saravanan, S.; Rana, D.; Nagendran, A.

2016-01-01

Highlights: • Four higher-alcohols namely, iso-butanol, n-pentanol, n-hexanol and n-octanol, were used. • Iso-butanol/diesel blend presented longest ignition delay, highest peak pressures and peak heat release rates. • NOx emissions were high for n-pentanol/diesel and n-hexanol/diesel blends at high load conditions. • Smoke opacity is highest for n-octanol/diesel blend and lowest for iso-butanol/diesel blend. • HC emissions are high for iso-butanol/diesel and n-pentanol/diesel blends. - Abstract: Higher alcohols are attractive next generation biofuels that can be extracted from sugary, starchy and ligno-cellulosic biomass feedstocks using sustainable pathways. Their viability for use in diesel engines has greatly improved ever since extended bio-synthetic pathways have achieved substantial yields of these alcohols using engineered micro-organisms. This study sets out to compare and analyze the effects of some higher alcohol/diesel blends on combustion and emission characteristics of a direct-injection diesel engine. Four test fuels containing 30% by vol. of iso-butanol, n-pentanol, n-hexanol and n-octanol (designated as ISB30, PEN30, HEX30 and OCT30 respectively) in ultra-low sulfur diesel (ULSD) were used. Results indicated that ISB30 experienced longest ignition delay and produced highest peaks of pressure and heat release rates (HRR) compared to other higher-alcohol blends. The ignition delay, peak pressure and peak HRR are found to be in the order of (from highest to lowest): ISB30 > PEN30 > HEX30 > OCT30 > ULSD. The combustion duration (CD) for all test fuels is in the sequence (from shortest to longest): ISB30 OCT30 > HEX30 > PEN30 > ISB30. HC emissions are high for ISB30 and PEN30 while it decreased favorably for HEX30 and OCT30. It was of the order (from highest to lowest): ISB30 > PEN30 > ULSD > HEX30 > OCT30. CO emissions of the blends followed the trend of smoke emissions and remained lower than ULSD with the following order (from highest to

Properties of chicken manure pyrolysis bio-oil blended with diesel and its combustion characteristics in RCEM, Rapid Compression and Expansion Machine

Directory of Open Access Journals (Sweden)

Sunbong Lee

2014-06-01

Full Text Available Bio-oil (bio-oil was produced from chicken manure in a pilot-scale pyrolysis facility. The raw bio-oil had a very high viscosity and sediments which made direct application to diesel engines difficult. The bio-oil was blended with diesel fuel with 25% and 75% volumetric ratio at the normal temperature, named as blend 25. A rapid compression and expansion machine was used for a combustion test under the experimental condition corresponding to the medium operation point of a light duty diesel engine using diesel fuel, and blend 25 for comparison. The injection related pressure signal and cylinder pressure signal were instantaneously picked up to analyze the combustion characteristics in addition to the measurement of NOx and smoke emissions. Blend 25 resulted in reduction of the smoke emission by 80% and improvements of the apparent combustion efficiency while the NOx emission increased by 40%. A discussion was done based on the analysis results of combustion.

Effects of Injection Rate Profile on Combustion Process and Emissions in a Diesel Engine

Directory of Open Access Journals (Sweden)

Fuqiang Bai

2017-01-01

Full Text Available When multi-injection is implemented in diesel engine via high pressure common rail injection system, changed interval between injection pulses can induce variation of injection rate profile for sequential injection pulse, though other control parameters are the same. Variations of injection rate shape which influence the air-fuel mixing and combustion process will be important for designing injection strategy. In this research, CFD numerical simulations using KIVA-3V were conducted for examining the effects of injection rate shape on diesel combustion and emissions. After the model was validated by experimental results, five different shapes (including rectangle, slope, triangle, trapezoid, and wedge of injection rate profiles were investigated. Modeling results demonstrate that injection rate shape can have obvious influence on heat release process and heat release traces which cause different combustion process and emissions. It is observed that the baseline, rectangle (flat, shape of injection rate can have better balance between NOx and soot emissions than the other investigated shapes. As wedge shape brings about the lowest NOx emissions due to retarded heat release, it produces the highest soot emissions among the five shapes. Trapezoid shape has the lowest soot emissions, while its NOx is not the highest one. The highest NOx emissions were produced by triangle shape due to higher peak injection rate.

Effects of ethanol added fuel on exhaust emissions and combustion in a premixed charge compression ignition diesel engine

Directory of Open Access Journals (Sweden)

Kim Yungjin

2015-01-01

Full Text Available The use of diesel engines for vehicle has been increasing recently due to its higher thermal efficiency and lower CO2 emission level. However, in the case of diesel engine, NOx increases in a high temperature combustion region and particulate matter is generated in a fuel rich region. Therefore, the technique of PCCI (premixed charge compression ignition is often studied to get the peak combustion temperature down and to make a better air-fuel mixing. However it also has got a limited operating range and lower engine power produced by the wall wetting and the difficulty of the ignition timing control. In this research, the effect of injection strategies on the injected fuel behavior, combustion and emission characteristics in a PCCI engine were investigated to find out the optimal conditions for fuel injection, and then ethanol blended diesel fuel was used to control the ignition timing. As a result, the combustion pressures and ROHR (rate of heat release of the blended fuel became lower, however, IMEP showed fewer differences. Especially in the case of triple injection, smoke could be reduced a little and NOx emission decreased a lot by using the ethanol blended fuel simultaneously without much decreasing of IMEP compared to the result of 100% diesel fuel.

Computational Study of Stratified Combustion in an Optical Diesel Engine

KAUST Repository

Jaasim, Mohammed

2017-03-28

Full cycle simulations of KAUST optical diesel engine were conducted in order to provide insights into the details of fuel spray, mixing, and combustion characteristics at different start of injection (SOI) conditions. Although optical diagnostics provide valuable information, the high fidelity simulations with matched parametric conditions improve fundamental understanding of relevant physical and chemical processes by accessing additional observables such as the local mixture distribution, intermediate species concentrations, and detailed chemical reaction rates. Commercial software, CONVERGE™, was used as the main simulation tool, with the Reynolds averaged Navier-Stokes (RANS) turbulence model and the multi-zone (SAGE) combustion model to compute the chemical reaction terms. SOI is varied from late compression ignition (CI) to early partially premixed combustion (PPC) conditions. The simulation results revealed a stronger correlation between fuel injection timing and combustion phasing for late SOI conditions, whereas the combustion phasing starts to decouple from SOI for early SOI cases. The predictions are consistent with the experimental observations, in terms of the overall trends in combustion and emission characteristics, while the high fidelity simulations provided further insights into the effects of mixture stratifications resulting from different SOI conditions.

Optical diagnostics for the investigation of combustion in a single cylinder of a diesel engine; Dieselmoottorin yksittaeisen sylinterin palamistapahtuman tutkiminen optisilla menetelmillae

Energy Technology Data Exchange (ETDEWEB)

Kytoelae, J.; Leino, I. [Waertsilae Diesel International Ltd, Vaasa (Finland); Hernberg, R.; Vattulainen, J. [Tampere Univ. of Technology (Finland). Lab. of Plasma Technology

1997-10-01

To be able to develop diesel engines with further lower exhaust emission levels, it is necessary to understand the different phases of combustion process taking place in a single cylinder of a diesel engine. In this project optical, both non-imaging and imaging techniques have been developed to study the temporal spatial flame behaviour and flame temperature in Wartsila medium speed diesel engines. Temperature of the diesel flame is a critical parameter for thermal NO{sub x} formation. The colour temperature of the diffusion diesel flame as a function of time (crank angle) has been determined pyrometrically based on the black body incandescence of the flame contained soot. To obtain spatially and temporally resolved information of the combustion process, flame visualization using CCD-techniques have been performed. Diesel combustion has been recorded both using special light-intensified high speed video recording (3000 fps) and with non-intensified, short exposure CCD-imaging. (orig.)

Higher alcohol–biodiesel–diesel blends: An approach for improving the performance, emission, and combustion of a light-duty diesel engine

International Nuclear Information System (INIS)

Imdadul, H.K.; Masjuki, H.H.; Kalam, M.A.; Zulkifli, N.W.M.; Alabdulkarem, Abdullah; Rashed, M.M.; Teoh, Y.H.; How, H.G.

2016-01-01

Highlights: • The fuel properties of higher alcohol blended biodiesel were improved. • Higher alcohol shows remarkable increase in the BP, BTE and decrease the BSFC. • Alcohols mixed with biodiesel diminishes HC, CO and smoke significantly. • CO 2 emissions of pentanol blended fuel decreases at maximum speed. • Higher alcohol blended biodiesel showed improved combustion. - Abstract: Pentanol is a long-chain alcohol with five carbons in its molecular structure and is produced from renewable feedstock, which may help to improve the challenging problems of energy security and environmental issues. In this investigation, the performance, emission, and combustion characteristics of a single-cylinder, four-stroke, water-cooled, direct-injection diesel engine were evaluated by using 10%, 15%, and 20% pentanol and Calophyllum inophyllum (CI) biodiesel blends in diesel under different speed conditions. The fuel properties of the blended fuels were measured and compared. Combustion attributes, such as cylinder pressure and heat-release rate, were also analyzed. Results indicated that increasing the proportion of pentanol in biodiesel blends improved the fuel properties compared with 20% blend of CI biodiesel (CI 20). The modified blends of pentanol showed reduced brake-specific fuel consumption with higher brake thermal efficiency and brake power than CI 20. Although the modified test blends showed a slightly higher nitric oxide emission, the carbon monoxide emission and unburned hydrocarbon emission for 15% and 20% blends of pentanol showed even better reduction than CI 20. Smoke emission was also reduced significantly. The carbon dioxide emission of the test blends were reduced at the maximum speed condition compared to CI 20. In terms of combustion, the modified test fuels exhibited a significant improvement, thus indicating better performance and emission. This study concluded that the 15% and 20% blends of biodiesel, diesel, and pentanol can optimize engine

Comparison of Diesel Spray Combustion in Different High-temperature, High-pressure Facilities

DEFF Research Database (Denmark)

Pickett, Lyle M.; Genzale, Caroline L.; Bruneaux, Gilles

2010-01-01

Diesel spray experimentation at controlled high-temperature and high-pressure conditions is intended to provide a more fundamental understanding of diesel combustion than can be achieved in engine experiments. This level of understanding is needed to develop the high-fidelity multi-scale CFD models...... participants in the ECN. Thus, in addition to the presentation of a comparative study, this paper demonstrates steps that are needed for other interested groups to participate in ECN spray research. We expect that this collaborative effort will generate a high-quality dataset to be used for advanced...

Improvement in the production of cylinder shirt of inner diesel combustion engines; Mejoras en la construccion de camisas de cilindro de motores de combustion interna ciclo diesel

Energy Technology Data Exchange (ETDEWEB)

Martinez-Perez, F.; Barroso-Moreno, A.

2013-06-01

This study deals with the different types of wear as well as other parameters present in the tribological system piston segment- cylinder in a combustion engine. By means of engineering methods were defined the wear rates in the three components of the system. The biggest wear in the analysis resulted in the cylinder shirt. Specialized methods applied were used to analyze the prevailing metallographic characteristics in its original construction, obtaining a gray melted iron with perlitic matrix. A new material with bainitic matrix has been proposed for increasing wear resistance. To demonstrate the efficiency of this new product, the experimental techniques carried out, were based on a dynamometric testing in a internal combustion engine diesel cycle Scania of 150 kW. It was exposed to a full charge during 500 h with 30 % of potency rising. Compared with the perlitic one, it has been proved that the bainitic matrix allows a better result. Besides, a superior dimensional stability was obtained. The piston segments had a similar wear rate in both materials in reference to the original tribological pair of the project. (Author)

Effects of Pilot Injection Timing and EGR on Combustion, Performance and Exhaust Emissions in a Common Rail Diesel Engine Fueled with a Canola Oil Biodiesel-Diesel Blend

Directory of Open Access Journals (Sweden)

Jun Cong Ge

2015-07-01

Full Text Available Biodiesel as a clean energy source could reduce environmental pollution compared to fossil fuel, so it is becoming increasingly important. In this study, we investigated the effects of different pilot injection timings from before top dead center (BTDC and exhaust gas recirculation (EGR on combustion, engine performance, and exhaust emission characteristics in a common rail diesel engine fueled with canola oil biodiesel-diesel (BD blend. The pilot injection timing and EGR rate were changed at an engine speed of 2000 rpm fueled with BD20 (20 vol % canola oil and 80 vol % diesel fuel blend. As the injection timing advanced, the combustion pressure, brake specific fuel consumption (BSFC, and peak combustion pressure (Pmax changed slightly. Carbon monoxide (CO and particulate matter (PM emissions clearly decreased at BTDC 20° compared with BTDC 5°, but nitrogen oxide (NOx emissions increased slightly. With an increasing EGR rate, the combustion pressure and indicated mean effective pressure (IMEP decreased slightly at BTDC 20° compared to other injection timings. However, the Pmax showed a remarkable decrease. The BSFC and PM emissions increased slightly, but the NOx emission decreased considerably.

Experimental and theoretical analysis of the combustion process at low loads of a diesel natural gas dual-fuel engine

International Nuclear Information System (INIS)

Li, Weifeng; Liu, Zhongchang; Wang, Zhongshu

2016-01-01

To construct an effective method to analyze the combustion process of dual fuel engines at low loads, effects of combustion boundaries on the combustion process of an electronically controlled diesel natural gas dual-fuel engine at low loads were investigated. Three typical combustion modes, including h, m and n, appeared under different combustion boundaries. In addition, the time-sequenced characteristic and the heat release rate-imbalanced characteristic were found in the dual fuel engine combustion process. To quantify these characteristics, two quantitative indicators, including the TSC (time-sequenced coefficient) and the HBC (HRR-balanced coefficient) were defined. The results show that increasing TSC and HBC can decrease HC (hydrocarbon) emissions and improve the BTE (brake thermal efficiency) significantly. The engine with the n combustion mode can obtain the highest BTE and the lowest HC emissions, followed by m, and then h. However, the combustion process of the engine will deteriorate sharply if boundary conditions are not strictly controlled in the n combustion mode. Based on the n combustion mode, advancing the start of diesel injection significantly, using large EGR (exhaust gas recirculation) rate and appropriately intake throttling can effectively reduce HC emissions and improve the BTE of dual fuel engines at low loads with relatively high natural gas PES (percentage energy substitution). - Highlights: • We reported three typical combustion modes of a dual-fuel engine at low loads. • Time-sequenced characteristic was put forward and qualified. • HRR-imbalanced characteristic was put forward and qualified. • Three combustion modes appeared as equivalence ratio/diesel injection timing varied. • The engine performance varied significantly with different combustion mode.

Effects of preheating of crude palm oil (CPO) on injection system, performance and emission of a diesel engine

International Nuclear Information System (INIS)

Bari, S.; Lim, T.H.; Yu, C.W.

2002-01-01

Crude palm oil (CPO) is one of the vegetable oils that have potential for use as fuels for diesel engines. CPO is renewable, and is safe and easy to handle. However, at room temperature (30-32 deg C) CPO has a viscosity about 10 times higher than that of diesel. To lower CPO's viscosity to the level of diesel's viscosity, a heating temperature of at least 92 deg C is needed. At this temperature, there is a concern that the close-fitting parts of the injection system might be affected. This study focused on finding out the effects of preheating of fuel on the injection system utilising a modified method of friction test, which involves injecting fuel outside the combustion chamber during motoring. Results show that preheating of CPO lowered CPO's viscosity and provided smooth fuel flow, but did not affect the injection system, even heating up to 100 deg C. Nevertheless, heating up to such a high temperature offered no benefits in terms of engine performance. However, heating is necessary for smooth flow and to avoid fuel filter clogging. Both can be achieved by heating CPO to 60 deg C. Combustion analyses comparisons between CPO and diesel found that CPO produced a higher peak pressure of 6%, a shorter ignition delay of 2.6 deg, a lower maximum heat release rate and a longer combustion period. Over the entire load range, CPO combustion produced average CO and NO emissions that were 9.2 and 29.3% higher, respectively, compared with those from diesel combustion. (Author)

Combustion Performance and Exhaust Emission of DI Diesel Engine Using Various Sources of Waste Cooking Oil

Science.gov (United States)

Afiq, Mohd; Azuhairi, Mohd; Jazair, Wira

2010-06-01

In Malaysia, more than 200-tone of cooking oil are used by domestic users everyday. After frying process, about a quarter of these cooking oil was remained and drained into sewage system. This will pollutes waterways and affects the ecosystem. The use of waste cooking oil (WCO) for producing bio-diesel was considered in economical factor which current production cost of bio-diesel production is higher in Malaysia due to higher price of palm oil. Thus, the aim of this study is to investigate the most suitable source of WCO to become a main source of bio-diesel for bio-diesel production in this country. To perform this research, three type of WCO were obtained from house's kitchen, cafeteria and mamak's restaurant. In this study, prospect of these bio-diesel source was evaluated based on its combustion performance and exhaust emissions operated in diesel engine in the form of waste cooking oil methyl ester (WCOME) and have been compared with pure diesel fuel. A 0.6 liter, single-cylinder, air-cooled direct injection diesel engine was used to perform this experiment. Experiment was done at variable engine loads and constant engine speed. As the result, among three stated WCOMEs, the one collected from house's kitchen gives the best performance in term of brake specific fuel consumption (bsfc) and brake power (BP) with lowest soot emission.

Predictive zero-dimensional combustion model for DI diesel engine feed-forward control

International Nuclear Information System (INIS)

Catania, Andrea Emilio; Finesso, Roberto; Spessa, Ezio

2011-01-01

Highlights: → Zero-dimensional low-throughput combustion model for real-time control in diesel engine applications. → Feed-forward control of MFB50, p max and IMEP in both conventional and PCCI combustion modes. → Capability of resolving the contribution to HRR of each injection pulse in multiple injection schedule. → Ignition delay and model parameters estimated through physically consistent and easy-to-tune correlations. - Abstract: An innovative zero-dimensional predictive combustion model has been developed for the estimation of HRR (heat release rate) and in-cylinder pressure traces. This model has been assessed and applied to conventional and PCCI (premixed charge compression ignition) DI diesel engines for model-based feed-forward control purposes. The injection rate profile is calculated on the basis of the injected fuel quantities and on the injection parameters, such as SOI (start of injection), ET (energizing time), and DT (dwell time), taking the injector NOD (nozzle opening delay) and NCD (nozzle closure delay) into account. The injection rate profile in turn allows the released chemical energy Q ch to be estimated. The approach starts from the assumption that, at each time instant, the HRR is proportional to the energy associated with the accumulated fuel mass in the combustion chamber. The main novelties of the proposed approach consist of the method that is adopted to estimate the fuel ignition delay and of injection rate splitting for HRR estimation. The procedure allows an accurate calculation to be made of the different combustion parameters that are important for engine calibration, such as SOC (start of combustion) and MFB50 (50% of fuel mass fraction burned angle). On the basis of an estimation of the fuel released chemical energy, of the heat globally exchanged from the charge with the walls and of the energy associated with the fuel evaporation, the charge net energy is calculated, for a subsequent evaluation of the in

Experimental studies on the combustion and emission characteristics of a diesel engine fuelled with used cooking oil methyl ester and its diesel blends

Energy Technology Data Exchange (ETDEWEB)

Lakshmi Narayana Rao, G.; Sampath, S. [Sri Venkateswara College of Engineering, Sriperumbudur (India); Rajagopal, K. [Jawaharlal Nehru Technological Univ., Hyderabad (India)

2008-04-01

Transesterified vegetable oils (biodiesel) are promising alternative fuel for diesel engines. Used vegetable oils are disposed from restaurants in large quantities. But higher viscosity restricts their direct use in diesel engines. In this study, used cooking oil was dehydrated and then transesterified using an alkaline catalyst. The combustion, performance and emission characteristics of Used Cooking oil Methyl Ester (UCME) and its blends with diesel oil are analyzed in a direct injection C.I. engine. The fuel properties and the combustion characteristics of UCME are found to be similar to those of diesel. A minor decrease in thermal efficiency with significant improvement in reduction of particulates, carbon monoxide and unburnt hydrocarbons is observed compared to diesel. The use of transesterified used cooking oil and its blends as fuel for diesel engines will reduce dependence on fossil fuels and also decrease considerably the environmental pollution. Of the various alternate fuels under consideration, biodiesel is the most promising due to the following reasons: (1) Biodiesel can be used in the existing engine without any modifications. (2) Biodiesel is made entirely from vegetable sources; it does not contain any sulfur, aromatic hydrocarbons, metals or crude oil residues. (3) Biodiesel is an oxygenated fuel; emissions of carbon monoxide and soot tend to reduce. (4) Unlike fossil fuels, the use of biodiesel does not contribute to global warming as CO{sub 2} emitted is once again absorbed by the plants grown for vegetable oil/biodiesel production. Thus CO{sub 2} balance is maintained. (5) The Occupational Safety and Health Administration classifies biodiesel as a non-flammable liquid. (6) The use of biodiesel can extend the life of diesel engines because it is more lubricating than petroleum diesel fuel. (7) Biodiesel is produced from renewable vegetable oils/animal fats and hence improves the fuel or energy security and economy independence.

Achieving clean and efficient engine operation up to full load by combining optimized RCCI and dual-fuel diesel-gasoline combustion strategies

International Nuclear Information System (INIS)

Benajes, Jesús; García, Antonio; Monsalve-Serrano, Javier; Boronat, Vicente

2017-01-01

Highlights: • Optimized dual-fuel strategy to cover the whole engine load-speed map. • EURO VI NOx levels up to 14 bar IMEP with fully and highly premixed RCCI strategies. • Dual-fuel provides up to 7% higher efficiency than CDC if urea consumption is considered. - Abstract: This experimental work investigates the capabilities of the reactivity controlled compression ignition combustion concept to be operated in the whole engine map and discusses its benefits when compared to conventional diesel combustion. The experiments were conducted using a single-cylinder medium-duty diesel engine fueled with regular gasoline and diesel fuels. The main modification on the stock engine architecture was the addition of a port fuel injector in the intake manifold. In addition, with the aim of extending the reactivity controlled compression ignition operating range towards higher loads, the piston bowl volume was increased to reduce the compression ratio of the engine from 17.5:1 (stock) down to 15.3:1. To allow the dual-fuel operation over the whole engine map without exceeding the mechanical limitations of the engine, an optimized dual-fuel combustion strategy is proposed in this research. The combustion strategy changes as the engine load increases, starting from a fully premixed reactivity controlled compression ignition combustion up to around 8 bar IMEP, then switching to a highly premixed reactivity controlled compression ignition combustion up to 15 bar IMEP, and finally moving to a mainly diffusive dual-fuel combustion to reach the full load operation. The engine mapping results obtained using this combustion strategy show that reactivity controlled compression ignition combustion allows fulfilling the EURO VI NOx limit up to 14 bar IMEP. Ultra-low soot emissions are also achieved when the fully premixed combustion is promoted, however, the soot levels rise notably as the combustion strategy moves to a less premixed pattern. Finally, the direct comparison of

Combustion Characteristics for Turbulent Prevaporized Premixed Flame Using Commercial Light Diesel and Kerosene Fuels

Directory of Open Access Journals (Sweden)

Mohamed S. Shehata

2014-01-01

Full Text Available Experimental study has been carried out for investigating fuel type, fuel blends, equivalence ratio, Reynolds number, inlet mixture temperature, and holes diameter of perforated plate affecting combustion process for turbulent prevaporized premixed air flames for different operating conditions. CO2, CO, H2, N2, C3H8, C2H6, C2H4, flame temperature, and gas flow velocity are measured along flame axis for different operating conditions. Gas chromatographic (GC and CO/CO2 infrared gas analyzer are used for measuring different species. Temperature is measured using thermocouple technique. Gas flow velocity is measured using pitot tube technique. The effect of kerosene percentage on concentration, flame temperature, and gas flow velocity is not linearly dependent. Correlations for adiabatic flame temperature for diesel and kerosene-air flames are obtained as function of mixture strength, fuel type, and inlet mixture temperature. Effect of equivalence ratio on combustion process for light diesel-air flame is greater than for kerosene-air flame. Flame temperature increases with increased Reynolds number for different operating conditions. Effect of Reynolds number on combustion process for light diesel flame is greater than for kerosene flame and also for rich flame is greater than for lean flame. The present work contributes to design and development of lean prevaporized premixed (LPP gas turbine combustors.

Numerical and Experimental Investigation of Combustion and Knock in a Dual Fuel Gas/Diesel Compression Ignition Engine

Directory of Open Access Journals (Sweden)

A. Gharehghani

2012-01-01

Full Text Available Conventional compression ignition engines can easily be converted to a dual fuel mode of operation using natural gas as main fuel and diesel oil injection as pilot to initiate the combustion. At the same time, it is possible to increase the output power by increasing the diesel oil percentage. A detailed performance and combustion characteristic analysis of a heavy duty diesel engine has been studied in dual fuel mode of operation where natural gas is used as the main fuel and diesel oil as pilot. The influence of intake pressure and temperature on knock occurrence and the effects of initial swirl ratio on heat release rate, temperature-pressure and emission levels have been investigated in this study. It is shown that an increase in the initial swirl ratio lengthens the delay period for auto-ignition and extends the combustion period while it reduces NOx. There is an optimum value of the initial swirl ratio for a certain mixture intake temperature and pressure conditions that can achieve high thermal efficiency and low NOx emissions while decreases the tendency to knock. Simultaneous increase of intake pressure and initial swirl ratio could be the solution to power loss and knock in dual fuel engine.

Numerical modeling on homogeneous charge compression ignition combustion engine fueled by diesel-ethanol blends

OpenAIRE

Hanafi H.; Hasan M.M; Rahman M.M; Noor M.M; Kadirgama K.; Ramasamy D.

2016-01-01

This paper investigates the performance and emission characteristics of HCCI engines fueled with oxygenated fuels (ethanol blend). A modeling study was conducted to investigate the impact of ethanol addition on the performance, combustion and emission characteristics of a Homogeneous Charge Compression Ignition (HCCI) engine fueled by diesel. One dimensional simulation was conducted using the renowned commercial software for diesel and its blend fuels with 5% (E5) and 10% ethanol (E10) (in vo...

Combustion Noise and Pollutants Prediction for Injection Pattern and Exhaust Gas Recirculation Tuning in an Automotive Common-Rail Diesel Engine

OpenAIRE

Arsie Ivan; Di Leo Rocco; Pianese Cesare; De Cesare Matteo

2015-01-01

In the last years, emissions standards for internal combustion engines are becoming more and more restrictive, particularly for NOx and soot emissions from Diesel engines. In order to comply with these requirements, OEMs have to face with innovative combustion concepts and/or sophisticate after-treatment devices. In both cases, the role of the Engine Management System (EMS) is increasingly essential, following the large number of actuators and sensors introduced and the need to meet customer ...

3-DIMENSIONAL Numerical Modeling on the Combustion and Emission Characteristics of Biodiesel in Diesel Engines

Science.gov (United States)

Yang, Wenming; An, Hui; Amin, Maghbouli; Li, Jing

2014-11-01

A 3-dimensional computational fluid dynamics modeling is conducted on a direct injection diesel engine fueled by biodiesel using multi-dimensional software KIVA4 coupled with CHEMKIN. To accurately predict the oxidation of saturated and unsaturated agents of the biodiesel fuel, a multicomponent advanced combustion model consisting of 69 species and 204 reactions combined with detailed oxidation pathways of methyl decenoate (C11H22O2), methyl-9-decenoate (C11H20O2) and n-heptane (C7H16) is employed in this work. In order to better represent the real fuel properties, the detailed chemical and thermo-physical properties of biodiesel such as vapor pressure, latent heat of vaporization, liquid viscosity and surface tension were calculated and compiled into the KIVA4 fuel library. The nitrogen monoxide (NO) and carbon monoxide (CO) formation mechanisms were also embedded. After validating the numerical simulation model by comparing the in-cylinder pressure and heat release rate curves with experimental results, further studies have been carried out to investigate the effect of combustion chamber design on flow field, subsequently on the combustion process and performance of diesel engine fueled by biodiesel. Research has also been done to investigate the impact of fuel injector location on the performance and emissions formation of diesel engine.

Modelling of fuel spray and combustion in diesel engines

Energy Technology Data Exchange (ETDEWEB)

Huttunen, M T; Kaario, O T [VTT Energy, Espoo (Finland)

1998-12-31

Fuel spray and air motion characteristics and combustion in direct injection (DI) diesel engines was studied using computational models of the commercial CFD-code FIRE. Physical subprocesses modelled included Lagrangian spray droplet movement and behaviour (atomisation, evaporation and interaction of spray droplets) and combustion of evaporated liquid spray in the gas phase. Fuel vapour combustion rate was described by the model of Magnussen and Hjertager. The standard k,{epsilon}-model was used for turbulence. In order to be able to predict combustion accurately, the fuel spray penetration should be predicted with reasonable accuracy. In this study, the standard drag coefficient had to be reduced in order to match the computed penetration to the measured one. In addition, the constants in the submodel describing droplet breakup also needed to be adjusted for closer agreement with the measurements. The characteristic time scale of fuel consumption rate k/C{sub R} {epsilon} strongly influenced the heat release and in-cylinder pressure. With a value around 2.0 to 5.0 for C{sub R}, the computed in-cylinder pressure during the compression stroke agreed quite well with the measurements. On the other hand, the in-cylinder pressure was underpredicted during the expansion stroke. This is partly due to the fact that hydrocarbon fuel combustion was modelled as a one-step reaction reading to CO{sub 2} and H{sub 2}O and inadequate description of the mixing of reactants and combustion products. (author) 16 refs.

Modelling of fuel spray and combustion in diesel engines

Energy Technology Data Exchange (ETDEWEB)

Huttunen, M.T.; Kaario, O.T. [VTT Energy, Espoo (Finland)

1997-12-31

Fuel spray and air motion characteristics and combustion in direct injection (DI) diesel engines was studied using computational models of the commercial CFD-code FIRE. Physical subprocesses modelled included Lagrangian spray droplet movement and behaviour (atomisation, evaporation and interaction of spray droplets) and combustion of evaporated liquid spray in the gas phase. Fuel vapour combustion rate was described by the model of Magnussen and Hjertager. The standard k,{epsilon}-model was used for turbulence. In order to be able to predict combustion accurately, the fuel spray penetration should be predicted with reasonable accuracy. In this study, the standard drag coefficient had to be reduced in order to match the computed penetration to the measured one. In addition, the constants in the submodel describing droplet breakup also needed to be adjusted for closer agreement with the measurements. The characteristic time scale of fuel consumption rate k/C{sub R} {epsilon} strongly influenced the heat release and in-cylinder pressure. With a value around 2.0 to 5.0 for C{sub R}, the computed in-cylinder pressure during the compression stroke agreed quite well with the measurements. On the other hand, the in-cylinder pressure was underpredicted during the expansion stroke. This is partly due to the fact that hydrocarbon fuel combustion was modelled as a one-step reaction reading to CO{sub 2} and H{sub 2}O and inadequate description of the mixing of reactants and combustion products. (author) 16 refs.

Combustion engine diagnosis model-based condition monitoring of gasoline and diesel engines and their components

CERN Document Server

Isermann, Rolf

2017-01-01

This book offers first a short introduction to advanced supervision, fault detection and diagnosis methods. It then describes model-based methods of fault detection and diagnosis for the main components of gasoline and diesel engines, such as the intake system, fuel supply, fuel injection, combustion process, turbocharger, exhaust system and exhaust gas aftertreatment. Additionally, model-based fault diagnosis of electrical motors, electric, pneumatic and hydraulic actuators and fault-tolerant systems is treated. In general series production sensors are used. It includes abundant experimental results showing the detection and diagnosis quality of implemented faults. Written for automotive engineers in practice, it is also of interest to graduate students of mechanical and electrical engineering and computer science. The Content Introduction.- I SUPERVISION, FAULT DETECTION AND DIAGNOSIS METHODS.- Supervision, Fault-Detection and Fault-Diagnosis Methods - a short Introduction.- II DIAGNOSIS OF INTERNAL COMBUST...

Analysis of the performance, emission and combustion characteristics of a turbocharged diesel engine fuelled with Jatropha curcas biodiesel-diesel blends using kernel-based extreme learning machine.

Science.gov (United States)

Silitonga, Arridina Susan; Hassan, Masjuki Haji; Ong, Hwai Chyuan; Kusumo, Fitranto

2017-11-01

The purpose of this study is to investigate the performance, emission and combustion characteristics of a four-cylinder common-rail turbocharged diesel engine fuelled with Jatropha curcas biodiesel-diesel blends. A kernel-based extreme learning machine (KELM) model is developed in this study using MATLAB software in order to predict the performance, combustion and emission characteristics of the engine. To acquire the data for training and testing the KELM model, the engine speed was selected as the input parameter, whereas the performance, exhaust emissions and combustion characteristics were chosen as the output parameters of the KELM model. The performance, emissions and combustion characteristics predicted by the KELM model were validated by comparing the predicted data with the experimental data. The results show that the coefficient of determination of the parameters is within a range of 0.9805-0.9991 for both the KELM model and the experimental data. The mean absolute percentage error is within a range of 0.1259-2.3838. This study shows that KELM modelling is a useful technique in biodiesel production since it facilitates scientists and researchers to predict the performance, exhaust emissions and combustion characteristics of internal combustion engines with high accuracy.

Selection of Fuel System for Modern Heavy Duty Diesel Engines

Directory of Open Access Journals (Sweden)

G. M. Kukharonok

2004-01-01

Full Text Available Fuel systems of diesel engines have been analyzed. The paper shows components of the systems, peculiarities of their manufacturing process. Difference in efficiency of the systems, their application and market prospects are considered in the paper. While solving problems to design a power installation the essence of fuel system selection is given on the basis of an internal combustion engine.

The effect of rapeseed oil biodiesel fuel on combustion, performance, and the emission formation process within a heavy-duty DI diesel engine

International Nuclear Information System (INIS)

Lešnik, Luka; Biluš, Ignacijo

2016-01-01

Highlights: • Sub-models for parameter determination can be derived using experimental results. • Proposed sub-models can be used for calculation of model parameters. • Biodiesel fuel reduces emissions compared to diesel fuel on full engine load. • Usage of biodiesel fuel slow down the emission formation rate. • Oxygen content in biodiesel fuel decreases the amount of formatted CO emissions. - Abstract: This study presents the influence of biodiesel fuel and blends with mineral diesel fuel on diesel engine performance, the combustion process, and the formation of emissions. The study was conducted numerically and experimentally. The aim of the study was to test the possibility of replacing mineral diesel fuel with biodiesel fuel made from rapeseed oil. Pure biodiesel fuel and three blends of biodiesel fuel with mineral diesel fuel were tested experimentally for that purpose on a heavy-duty bus diesel engine. The engine’s performance, in-cylinder pressure, fuel consumption, and the amount of produced NO_x and CO emissions were monitored during experimental measurements, which were repeated numerically using the AVL BOOST simulation program. New empirical sub-models are proposed for determining a combustion model and emission models parameters. The proposed sub-models allow the determination of necessary combustion and emission model parameters regarding the properties of the tested fuel and the engine speed. When increasing the percentage of biodiesel fuel within the fuel blends, the reduction in engine torque and brake mean effective pressures are obtained for most of the test regimes. The reduction is caused due to the lower calorific value of the biodiesel fuel. Higher oxygen content in biodiesel fuel contributes to a better oxidation process within the combustion chamber when running on pure biodiesel or its blends. Better oxidation further results in a reduction of the formatted carbon and nitrogen oxides. The reduction of carbon emission is also

New concept for low emission diesel combustion. 2nd Report. Combustion improvement by applying EGR and oxygenated fuel; Teikogai diesel engine no nensho concept. EGR, gansanso nenryo ni yoru nensho kaizen

Energy Technology Data Exchange (ETDEWEB)

Yokota, H.; Nakajima, H.; Kakegawa, T. [Hino Motors, Ltd., Tokyo (Japan)

1998-05-01

Described herein are performance of a new concept of premixed, multiple injection combustion, in which part of the fuel is injected into the combustion chamber at the early stage and the remainder is injected in the ordinary manner, and characteristics of the exhaust gases. Also described are the effects of EGR and oxygenated fuel on reduced HC emissions and fuel consumption. The ordinary premixed, multiple injection combustion system has problems related to fuel efficiency, and HC and particulate missions. When combined with an EGR system, this system reduces HC emissions to one-third. MTBE shows an effect of improving fuel efficiency, when mixed with diesel fuel. No particulate matter is exhausted and fuel efficiency is improved by 6%, when MTBE is present in the fuel at 30% by weight. The pre-mixture is less homogeneous in the absence of EGR and oxygenated fuel, producing a luminous flame observed in the fuel-rich region. No such a flame is observed, when MTBE is added to the fuel and suction air temperature is increased to the level corresponding to that associated with EGR, conceivably resulting from increased suction air temperature and lower boiling point of MTBE, which together make the pre-mixture leaner and more homogeneous. 7 refs., 9 figs., 2 tabs.

Improvement in the production of cylinder shirt of inner diesel combustion engines

International Nuclear Information System (INIS)

Martinez-Perez, F.; Barroso-Moreno, A.

2013-01-01

This study deals with the different types of wear as well as other parameters present in the tribological system piston segment- cylinder in a combustion engine. By means of engineering methods were defined the wear rates in the three components of the system. The biggest wear in the analysis resulted in the cylinder shirt. Specialized methods applied were used to analyze the prevailing metallographic characteristics in its original construction, obtaining a gray melted iron with perlitic matrix. A new material with bainitic matrix has been proposed for increasing wear resistance. To demonstrate the efficiency of this new product, the experimental techniques carried out, were based on a dynamometric testing in a internal combustion engine diesel cycle Scania of 150 kW. It was exposed to a full charge during 500 h with 30 % of potency rising. Compared with the perlitic one, it has been proved that the bainitic matrix allows a better result. Besides, a superior dimensional stability was obtained. The piston segments had a similar wear rate in both materials in reference to the original tribological pair of the project. (Author)

Predictive zero-dimensional combustion model for DI diesel engine feed-forward control

Energy Technology Data Exchange (ETDEWEB)

Catania, Andrea Emilio; Finesso, Roberto [IC Engines Advanced Laboratory, Politecnico di Torino, c.so Duca degli Abruzzi 24, 10129 Torino (Italy); Spessa, Ezio, E-mail: ezio.spessa@polito.it [IC Engines Advanced Laboratory, Politecnico di Torino, c.so Duca degli Abruzzi 24, 10129 Torino (Italy)

2011-09-15

Highlights: {yields} Zero-dimensional low-throughput combustion model for real-time control in diesel engine applications. {yields} Feed-forward control of MFB50, p{sub max} and IMEP in both conventional and PCCI combustion modes. {yields} Capability of resolving the contribution to HRR of each injection pulse in multiple injection schedule. {yields} Ignition delay and model parameters estimated through physically consistent and easy-to-tune correlations. - Abstract: An innovative zero-dimensional predictive combustion model has been developed for the estimation of HRR (heat release rate) and in-cylinder pressure traces. This model has been assessed and applied to conventional and PCCI (premixed charge compression ignition) DI diesel engines for model-based feed-forward control purposes. The injection rate profile is calculated on the basis of the injected fuel quantities and on the injection parameters, such as SOI (start of injection), ET (energizing time), and DT (dwell time), taking the injector NOD (nozzle opening delay) and NCD (nozzle closure delay) into account. The injection rate profile in turn allows the released chemical energy Q{sub ch} to be estimated. The approach starts from the assumption that, at each time instant, the HRR is proportional to the energy associated with the accumulated fuel mass in the combustion chamber. The main novelties of the proposed approach consist of the method that is adopted to estimate the fuel ignition delay and of injection rate splitting for HRR estimation. The procedure allows an accurate calculation to be made of the different combustion parameters that are important for engine calibration, such as SOC (start of combustion) and MFB50 (50% of fuel mass fraction burned angle). On the basis of an estimation of the fuel released chemical energy, of the heat globally exchanged from the charge with the walls and of the energy associated with the fuel evaporation, the charge net energy is calculated, for a subsequent

Effect of oxygenated fuel on premixed lean diesel combustion; Kihaku yokongo diesel nensho ni oyobosu gansanso nenryo kongo keiyu no eikyo

Energy Technology Data Exchange (ETDEWEB)

Sasaki, S.; Miyamoto, T.; Harada, A.; Akagawa, H.; Tsujimura, K. [New ACE Institute Co. Ltd., Tokyo (Japan)

1998-05-01

Because injection timing in diesel engines is early in a premixed lean diesel combustion system using early fuel injection, ignition timing is determined by ignitability of the fuel used. The conventional diesel fuel, which has good ignitability, causes excessively early ignition, thus aggravating fuel consumption. In order to reduce cylinder temperature with an aim of delaying ignition timing to improve the fuel consumption, attempts are being made on using low cetane fuels to reduce CO2 gas supply or compression ratio, and to vary ignitability of the fuels. The present study investigated ignition timing control and properties of exhausts by mixing different types of oxygenated fuels into light oil. Mixing the oxygenated fuels into light oil proved that the ignition timing can be controlled, and mixing such low cetane fuels as ethanol and MTBE achieved improvement in fuel consumption. Trial use of the oxygenated fuels aggravated CO concentration, which is caused because the cylinder temperature was reduced. Numerical calculations suggest that use of fuels with faster evaporation speed and lower cetane number is effective in improving the fuel consumption and the exhausts. 12 refs., 9 figs., 2 tabs.

Numerical simulation of fuel sprays and combustion in a premixed lean diesel engine; Kihaku yokongo diesel kikan ni okeru nenryo funmu to nensho no suchi simulation

Energy Technology Data Exchange (ETDEWEB)

Miyamoto, T; Harada, A; Sasaki, S; Shimazaki, N; Hashizume, T; Akagawa, H; Tsujimura, K

1997-10-01

Fuel sprays and combustion in a direct injection Premixed lean Diesel Combustion (PREDIC) engine, which can make smokeless combustion with little NOx emission, is studied numerically. Numerical simulation was carried out by means of KIVA II based computer code with a combustion submodel. The combustion submodel describes the formation of combustible fuel vapor by turbulent mixing and four-step chemical reaction which includes low temperature oxidation. Comparison between computation and experiment shows qualitatively good agreement in terms of heat release rate and NO emission. Computational results indicate that the combustion is significantly influenced by fuel spray characteristics and injection timing to vary NO emission. 10 refs., 8 figs., 1 tab.

Design and approval of EPS diesel systems in German NPP

Energy Technology Data Exchange (ETDEWEB)

Kollmer, A.A., E-mail: anton.kollmer@tuev-sued.de [TUV SUD Industrie Service GmbH, Munich (Germany)

2014-07-01

Not at least because of 'Fukushima accident', Emergency power supply (EPS) systems with diesel engines are regarded as higher safety-important as 20 years ago. This presentation shows the design and approval of the emergency power facilities of the German nuclear power plants. It deals with the essential details e. g.: EPS Diesel integration to main power grid of the German BWR and PWR; Procedure for 'Loss of off-site power (LOOP)-Design'; Design robustness of AC Power Supply (Design requirements: independent redundancies, airplane crash, explosion pressure wave, earth-quake); Cooling systems (chilled by river water, air, well water, stored water volume); Layout of the stationary emergency Diesel generator (fuel supply, starting system); Layout of the bunkered EDG with directly driven emergency feed water pump; Robustness of AC power supply beyond design; Layout of mobile chilling equipment for diesel engines; Layout of mobile Diesel gen-sets (200 kVA and 1250 kVA); German Requirements of KTA 3702 versus US-IEE 323; Construction, Materials and Testing of EDG; Maintenance (in-service inspections, operation, Repair); Lessons learned (e. g. crank house cracks, start failure due to too much oil in the combustion chamber) (author)

Improving of diesel combustion-pollution-fuel economy and performance by gasoline fumigation

International Nuclear Information System (INIS)

Şahin, Zehra; Durgun, Orhan

2013-01-01

Highlights: • The effects of gasoline fumigation on the engine performance and NO x emission were investigated in Ford XLD 418 T automotive diesel engine. • Gasoline at approximately (2, 4, 6, 8 10, and 12)% (by vol.) ratios was injected into intake air by a carburetor. • GF enhances effective power and reduces brake specific fuel consumption, cost, and NO x emission. - Abstract: One of the most important objectives of the studies worldwide is to improve combustion of diesel engine to meet growing energy needs and to reduce increasing environmental pollution. To accomplish this goal, especially to reduce pollutant emissions, researchers have focused their interest on the field of alternative fuels and alternative solutions. Gasoline fumigation (GF) is one of these alternative solutions, by which diesel combustion, fuel economy, and engine performance are improved, and environmental pollution is decreased. In the fumigation method, gasoline is injected into intake air, either by a carburetor, which main nozzle section is adjustable or by a simple injection system. In the present experimental study, a simple carburetor was used, and the effects of gasoline fumigation at (2, 4, 6, 8, 10, 12)% (by vol.) gasoline ratios on the combustion, NO x emission, fuel economy, and engine performance sophisticatedly investigated for a fully instrumented, four-cylinder, water-cooled indirect injection (IDI), Ford XLD 418 T automotive diesel engine. Tests were conducted for each of the above gasoline fumigation ratios at three different speeds and for (1/1, 3/4, and 1/2) fuel delivery ratios (FDRs). GF test results showed that NO x emission is lower than that of neat diesel fuel (NDF). NO x emission decreases approximately 4.20%, 2.50%, and 9.65% for (1/1, 3/4, and 1/2) FDRs, respectively. Effective power increases approximately 2.38% for 1/1 FDR. At (2500 and 3000) rpms, effective power decreases at low gasoline ratios, but it increases at high gasoline ratios for 3/4 and 1

Shale oil combustion

International Nuclear Information System (INIS)

Al-dabbas, M.A.

1992-05-01

A 'coutant' carbon steel combustion chamber cooled by water jacket was conslructed to burn diesel fuel and mixlure of shale oil and diesel fuels. During experimental work nir fuel ratio was determined, temperaturces were measured using Chromel/ Almel thermocouple, finally the gasous combustion product analysis was carricd out using gas chromatograph technique. The constructed combustion chamber was operating salisfactory for several hours of continous work. According to the measurements it was found that: the flame temperature of a mixture of diesel and shale oil fuels was greater than the flame temperature of diesel fuel. and the sulfer emissious of a mixture of diesel and shale oil fuels was higher than that of diesel fuel. Calculation indicated that the dry gas energy loss was very high and the incomplete combustion energy loss very small. (author). 23 refs., 35 figs

Shale oil combustion

Energy Technology Data Exchange (ETDEWEB)

Al-dabbas, M A

1992-05-01

A `coutant` carbon steel combustion chamber cooled by water jacket was conslructed to burn diesel fuel and mixlure of shale oil and diesel fuels. During experimental work nir fuel ratio was determined, temperaturces were measured using Chromel/ Almel thermocouple, finally the gasous combustion product analysis was carricd out using gas chromatograph technique. The constructed combustion chamber was operating salisfactory for several hours of continous work. According to the measurements it was found that: the flame temperature of a mixture of diesel and shale oil fuels was greater than the flame temperature of diesel fuel. and the sulfer emissious of a mixture of diesel and shale oil fuels was higher than that of diesel fuel. Calculation indicated that the dry gas energy loss was very high and the incomplete combustion energy loss very small. (author). 23 refs., 35 figs.

Investigation on the effects of pilot injection on low temperature combustion in high-speed diesel engine fueled with n-butanol–diesel blends

International Nuclear Information System (INIS)

Huang, Haozhong; Liu, Qingsheng; Yang, Ruzhi; Zhu, Tianru; Zhao, Ruiqing; Wang, Yaodong

2015-01-01

Highlights: • The effects of pre-injected timing and pre-injected mass were studied in CI engine. • The addition of n-butanol consumed OH free radicals, which delayed the ignition time. • With the increase of n-butanol, the BSFC and MPRR increased, NO_x and soot decreased. • With the advance of pilot injection timing, the BSFC increased, NO_x and soot decreased. • With the increase of pilot injection mass, NO_x increased, soot decreased then increased. - Abstract: The effect of pilot injection timing and pilot injection mass on combustion and emission characteristics under medium exhaust gas recirculation (EGR (25%)) condition were experimentally investigated in high-speed diesel engine. Diesel fuel (B0), two blends of butanol and diesel fuel denoted as B20 (20% butanol and 80% diesel in volume), and B30 (30% butanol and 70% diesel in volume) were tested. The results show that, for all fuels, when advancing the pilot injection timing, the peak value of heat release rate decreases for pre-injection fuel, but increases slightly for the main-injection fuel. Moreover, the in-cylinder pressure peak value reduces with the rise of maximum pressure rise rate (MPRR), while NO_x and soot emissions reduce. Increasing the pilot injection fuel mass, the peak value of heat release rate for pre-injected fuel increases, but for the main-injection, the peak descends, and the in-cylinder pressure peak value and NO_x emissions increase, while soot emission decreases at first and then increases. Blending n-butanol in diesel improves soot emissions. When pilot injection is adopted, the increase of n-butanol ratio causes the MPRR increasing and the crank angle location for 50% cumulative heat release (CA50) advancing, as well as NO_x and soot emissions decreasing. The simulation of the combustion of n-butanol–diesel fuel blends, which was based on the n-heptane–n-butanol–PAH–toluene mixing mechanism, demonstrated that the addition of n-butanol consumed OH free radicals

Etudes théoriques et expérimentales de la combustion dans les moteurs Diesel d'automobiles à injection directe et à préchambre Theoretical and Experimental Research on Combustion in Diesel Automotive Engines with Direct Injection and a Prechamber

Directory of Open Access Journals (Sweden)

Douaud A.

2006-11-01

Full Text Available Certaines techniques récemment développées pour la modélisation mathématique et les investigations expérimentales sur moteur Diesel sont présentées. On insiste sur l'importance de la validation croisée entre calcul et mesure. Taux d'injection, aérodynamique interne, développement du spray sont analysés en relation avec la géométrie des chambres de combustion. Des exemples, portant principalement sur des considérations de rendement énergétiques et d'émissions polluantes sont présentés à la fois sur le moteur Diesel à préchambre et le moteur Diesel à injection directe. Various techniques developed recently for the mathematical modeling and experimental investigating of diesel engines are described. Emphasis is placed on the importance of crosschecking between computing and measuring. The injection rate, internal aerodynamics and spray development are analyzed in relation to the geometry of combustion chambers. Examples mainly concerning matters of energy efficiency and pollutant emissions are given for diesel engines both with a prechamber and with direct injection.

Development and validation of double and single Wiebe function for multi-injection mode Diesel engine combustion modelling for hardware-in-the-loop applications

International Nuclear Information System (INIS)

Maroteaux, Fadila; Saad, Charbel; Aubertin, Fabrice

2015-01-01

Highlights: • Modelling of Diesel engine combustion with multi-injection mode was conducted. • Double and single Wiebe correlations for pilot, main and post combustion processes were calibrated. • Ignition delay time correlations have been developed and calibrated using experimental data for each injection. • The complete in-cylinder model has been applied successfully to real time simulations on HiL test bed. - Abstract: The improvement of Diesel engine performances in terms of fuel consumption and pollutant emissions has a huge impact on management system and diagnostic procedure. Validation and testing of engine performances can benefit from the use of theoretical models, for the reduction of development time and costs. Hardware in the Loop (HiL) test bench is a suitable way to achieve these objectives. However, the increasing complexity of management systems rises challenges for the development of very reduced physical models able to run in real time applications. This paper presents an extension of a previously developed phenomenological Diesel combustion model suitable for real time applications on a HiL test bench. In the earlier study, the modelling efforts have been targeted at high engine speeds with a very short computational time window, and where the engine operates with single injection. In the present work, a modelling of in-cylinder processes at low and medium engine speeds with multi-injection is performed. In order to reach an adequate computational time, the combustion progress during the pilot and main injection periods has been treated through a double Wiebe function, while the post combustion period has required a single Wiebe function. This paper describes the basic system models and their calibration and validation against experimental data. The use of the developed correlations of Wiebe coefficients and ignition delay times for each combustion phase, included in the in-cylinder crank angle global model, is applied for the prediction

HERCULES Advanced Combustion Concepts Test Facility: Spray/Combustion Chamber

Energy Technology Data Exchange (ETDEWEB)

Herrmann, K. [Eidgenoessische Technische Hochschule (ETH), Labor fuer Aerothermochemie und Verbrennungssysteme, Zuerich (Switzerland)

2004-07-01

This yearly report for 2004 on behalf of the Swiss Federal Office of Energy (SFOE) at the Laboratory for Aero-thermochemistry and Combustion Systems at the Federal Institute of Technology ETH in Zurich, Switzerland, presents a review of work being done within the framework of HERCULES (High Efficiency R and D on Combustion with Ultra Low Emissions for Ships) - the international R and D project concerning new technologies for ships' diesels. The work involves the use and augmentation of simulation models. These are to be validated using experimental data. The report deals with the development of an experimental set-up that will simulate combustion in large two-stroke diesel engines and allow the generation of reference data. The main element of the test apparatus is a spray / combustion chamber with extensive possibilities for optical observation under variable flow conditions. The results of first simulations confirm concepts and shall help in further work on the project. The potential offered by high-speed camera systems was tested using the institute's existing HTDZ combustion chamber. Further work to be done is reviewed.

Investigation of the effects of renewable diesel fuels on engine performance, combustion, and emissions

KAUST Repository

Ogunkoya, Dolanimi

2015-01-01

A study was undertaken to investigate renewable fuels in a compression-ignition internal combustion engine. The focus of this study was the effect of newly developed renewable fuels on engine performance, combustion, and emissions. Eight fuels were investigated, and they include diesel, jet fuel, a traditional biodiesel (fatty acid methyl ester: FAME), and five next generation biofuels. These five fuels were derived using a two-step process: hydrolysis of the oil into fatty acids (if necessary) and then a thermo-catalytic process to remove the oxygen via a decarboxylation reaction. The fuels included a fed batch deoxygenation of canola derived fatty acids (DCFA), a fed batch deoxygenation of canola derived fatty acids with varying amounts of H2 used during the deoxygenation process (DCFAH), a continuous deoxygenation of canola derived fatty acids (CDCFA), fed batch deoxygenation of lauric acid (DLA), and a third reaction to isomerize the products of the deoxygenated canola derived fatty acid alkanes (IPCF). Diesel, jet fuel, and biodiesel (FAME) have been used as benchmarks for comparing with the newer renewable fuels. The results of the experiments show slightly lower mechanical efficiency but better brake specific fuel consumption for the new renewable fuels. Results from combustion show shorter ignition delays for most of the renewable (deoxygenated) fuels with the exception of fed batch deoxygenation of lauric acid. Combustion results also show lower peak in-cylinder pressures, reduced rate of increase in cylinder pressure, and lower heat release rates for the renewable fuels. Emission results show an increase in hydrocarbon emissions for renewable deoxygenated fuels, but a general decrease in all other emissions including NOx, greenhouse gases, and soot. Results also demonstrate that isomers of the alkanes resulting from the deoxygenation of the canola derived fatty acids could be a potential replacement to conventional fossil diesel and biodiesel based on the

A numerical study of the effects of injection rate shape on combustion and emission of diesel engines

Directory of Open Access Journals (Sweden)

He Zhixia

2014-01-01

Full Text Available The spray characteristics including spray droplet sizes, droplet distribution, spray tip penetration length and spray diffusion angle directly affects the mixture process of fuel and oxygen and then plays an important role for the improvement of combustion and emission performance of diesel engines. Different injection rate shapes may induce different spray characteristics and then further affect the subsequent combustion and emission performance of diesel engines. In this paper, the spray and combustion processes based on four different injection rate shapes with constant injection duration and injected fuel mass were simulated in the software of AVL FIRE. The numerical models were validated through comparing the results from the simulation with those from experiment. It was found that the dynamic of diesel engines with the new proposed hump shape of injection rate and the original saddle shape is better than that with the injection rate of rectangle and triangle shape, but the emission of NOX is higher. And the soot emission is lowest during the late injection period for the new hump-shape injection rate because of a higher oxidation rate with a better mixture between fuel and air under the high injection pressure.

An investigation of late-combustion soot burnout in a DI diesel engine using simultaneous planar imaging of soot and OH radical

Energy Technology Data Exchange (ETDEWEB)

John E. Dec; Peter L. Kelly-Zion

1999-10-01

Diesel engine design continues to be driven by the need to improve performance while at the same time achieving further reductions in emissions. The development of new designs to accomplish these goals requires an understanding of how the emissions are produced in the engine. Laser-imaging diagnostics are uniquely capable of providing this information, and the understanding of diesel combustion and emissions formation has been advanced considerably in recent years by their application. However, previous studies have generally focused on the early and middle stages of diesel combustion. These previous laser-imaging studies do provide important insight into the soot formation and oxidation processes during the main combustion event. They indicate that prior to the end of injection, soot formation is initiated by fuel-rich premixed combustion (equivalence ratio > 4) near the upstream limit of the luminous portion of the reacting fuel jet. The soot is then oxidized at the diffusion flame around the periphery of the luminous plume. Under typical diesel engine conditions, the diffusion flame does not burn the remaining fuel and soot as rapidly as it is supplied, resulting in an expanding region of rich combustion products and soot. This is evident in natural emission images by the increasing size of the luminous soot cloud prior to the end of injection. Hence, the amount of soot in the combustion chamber typically increases until shortly after the end of fuel injection, at which time the main soot formation period ends and the burnout phase begins. Sampling valve and two-color pyrometry data indicate that the vast majority (more than 90%) of the soot formed is oxidized before combustion ends; however, it is generally thought that a small fraction of this soot from the main combustion zones is not consumed and is the source of tail pipe soot emissions.

Analysis of BJ493 diesel engine lubrication system properties

Science.gov (United States)

Liu, F.

2017-12-01

The BJ493ZLQ4A diesel engine design is based on the primary model of BJ493ZLQ3, of which exhaust level is upgraded to the National GB5 standard due to the improved design of combustion and injection systems. Given the above changes in the diesel lubrication system, its improved properties are analyzed in this paper. According to the structures, technical parameters and indices of the lubrication system, the lubrication system model of BJ493ZLQ4A diesel engine was constructed using the Flowmaster flow simulation software. The properties of the diesel engine lubrication system, such as the oil flow rate and pressure at different rotational speeds were analyzed for the schemes involving large- and small-scale oil filters. The calculated values of the main oil channel pressure are in good agreement with the experimental results, which verifies the proposed model feasibility. The calculation results show that the main oil channel pressure and maximum oil flow rate values for the large-scale oil filter scheme satisfy the design requirements, while the small-scale scheme yields too low main oil channel’s pressure and too high. Therefore, application of small-scale oil filters is hazardous, and the large-scale scheme is recommended.

Optimizing diesel combustion behaviour with tailor-made fuels from biomass

Energy Technology Data Exchange (ETDEWEB)

Kremer, Florian; Heuser, Benedikt [RWTH Aachen Univ. (Germany). Lehrstuhl fuer Verbrennungskraftmaschinen; Klankermayer, Juergen [RWTH Aachen Univ. (Germany). Inst. fuer Technische und Makromolekulare Chemie; Pischinger, Stefan

2013-06-01

Modem biofuels offer a vast potential to decrease engine out emissions while at the same time allowing a reduction of greenhouse gases produced from individual mobility. In order to deeply investigate and improve the complete path from biofuel production to combustion, in 2007 the cluster of excellence ''Tailor-Made Fuels from Biomass'' was installed at RWTH Aachen University. Since the start of the work in the cluster a whole variety of possible fuel candidates were identified and investigated, eventually leading to the definition of 2-methyltetrahydrofurane (2-MTHF) as a tailor-made biofuel for passenger car diesel engines. With 2-MTHF, a nearly soot-free combustion can be realized. This soot-free combustion behavior can partially be explained by the low self-ignition tendency and the therefore observed long ignition delays. Hereby, a good mixture preparation can be realized. This long ignition delay also results in high HC- and CO emissions, though, which are partially accompanied by increased noise emissions. In this work, the addition of di-n-butylether (DNBE) to 2-MTHF to reduce the described disadvantages will be analyzed. DNBE, a fuel that can be obtained via a reaction pathway defined in TMFB, is characterized by an extremely high Cetane number (CN- 100) and therefore very high self-ignitability. The effects of different mixtures of DNBE and 2-MTHF from 0% to 100% especially on the HC- and CO- and noise emissions will be carefully analyzed. In addition, the overall emission performance will be compared to standard EN590 Diesel as reference fuel. The results show that an adapted addition of DNBE to 2-MTHF can lead to a significant reduction of HC-, CO- and noise emissions while not sacrificing the benefits gained from the 2-MTHF's long ignition delays with regard to the particulate emissions. It can be proven that the use of two tailored biofuels with different self-ignitability such as 2-MTHF and DNBE allows to tailor the

Combustion and exhaust emission characteristics of a dual fuel compression ignition engine operated with pilot Diesel fuel and natural gas

International Nuclear Information System (INIS)

Papagiannakis, R.G.; Hountalas, D.T.

2004-01-01

Towards the effort of reducing pollutant emissions, especially soot and nitrogen oxides, from direct injection Diesel engines, engineers have proposed various solutions, one of which is the use of a gaseous fuel as a partial supplement for liquid Diesel fuel. These engines are known as dual fuel combustion engines, i.e. they use conventional Diesel fuel and a gaseous fuel as well. This technology is currently reintroduced, associated with efforts to overcome various difficulties of HCCI engines, using various fuels. The use of natural gas as an alternative fuel is a promising solution. The potential benefits of using natural gas in Diesel engines are both economical and environmental. The high autoignition temperature of natural gas is a serious advantage since the compression ratio of conventional Diesel engines can be maintained. The present contribution describes an experimental investigation conducted on a single cylinder DI Diesel engine, which has been properly modified to operate under dual fuel conditions. The primary amount of fuel is the gaseous one, which is ignited by a pilot Diesel liquid injection. Comparative results are given for various engine speeds and loads for conventional Diesel and dual fuel operation, revealing the effect of dual fuel combustion on engine performance and exhaust emissions

Developments of DPF systems with mesh laminated structures. Performances of DPF systems which consist of the metal-mesh laminated filter combustion with the alumina-fiber mesh, and the combustion device of trapped diesel particles; Mesh taso kozo no DPF no kaihatsu. Kinzokusen to arumina sen`i mesh ni yoru fukugo filter to filter heiyo heater ni yoru DPF no seino

Energy Technology Data Exchange (ETDEWEB)

Kojima, T; Tange, A; Matsuda, K [NHK Spring Co. Ltd., Yokohama (Japan)

1997-10-01

For the purpose of continuous run without any maintenance, new DPF (diesel particulate filter)systems laminated by both metal-wire mesh and alumina-fiber mesh alternately, are under the developments. The perfect combustion of trapped diesel particulate can be achieved by a couple of the resistance heating devices inserted into the filter. 5 refs., 7 figs., 3 tabs.

Turbulence-combustion interaction in direct injection diesel engine

Directory of Open Access Journals (Sweden)

Bencherif Mohamed

2014-01-01

Full Text Available The experimental measures of chemical species and turbulence intensity during the closed part of the engine combustion cycle are today unattainable exactly. This paper deals with numerical investigations of an experimental direct injection Diesel engine and a commercial turbocharged heavy duty direct injection one. Simulations are carried out with the kiva3v2 code using the RNG (k-ε model. A reduced mechanism for n-heptane was adopted for predicting auto-ignition and combustion processes. From the calibrated code based on experimental in-cylinder pressures, the study focuses on the turbulence parameters and combustion species evolution in the attempt to improve understanding of turbulence-chemistry interaction during the engine cycle. The turbulent kinetic energy and its dissipation rate are taken as representative parameters of turbulence. The results indicate that chemistry reactions of fuel oxidation during the auto-ignition delay improve the turbulence levels. The peak position of turbulent kinetic energy coincides systematically with the auto-ignition timing. This position seems to be governed by the viscous effects generated by the high pressure level reached at the auto-ignition timing. The hot regime flame decreases rapidly the turbulence intensity successively by the viscous effects during the fast premixed combustion and heat transfer during other periods. It is showed that instable species such as CO are due to deficiency of local mixture preparation during the strong decrease of turbulence energy. Also, an attempt to build an innovative relationship between self-ignition and maximum turbulence level is proposed. This work justifies the suggestion to determine otherwise the self-ignition timing.

Influences of HVO and FAME on the combustion and emissions of modern passenger car diesel engines

International Nuclear Information System (INIS)

Stengel, Benjamin; Sadlowski, Thomas; Wichmann, Volker; Harndorf, Horst

2014-01-01

In the framework of this study engine tests were performed with FAME (fatty acid methyl ester) and HVO (hydrotreated vegetable oil) as straight fuels using a EURO-VI passenger car diesel engine. Standard diesel fuel (EN 590) was used as reference. To analyze the impacts of the biofuels on the combustion process the heat release rates were calculated from in-cylinder pressure measurements using a single-zone model. Furthermore emissions were measured and ECU data was recorded. Results from engine tests showed that both HVO and FAME positively affect the combustion by a decreased ignition delay due to its higher cetane number. Raw exhaust emissions of soot were clearly reduced with HVO while CO and THC emissions showed minor reductions. During FAME operation ECU control settings were shifted due to its lower heating value. FAME showed reductions of soot by 60 % which is caused by the fuel's oxygen content while NO x emissions where slightly increased. However, a fuel adapted ECU calibration could optimize, e.g., the injection timing and EGR to further reduce emissions. Tailpipe emissions were not affected by HVO and FAME as the exhaust aftertreatment systems worked similarly efficient for all three fuels.

Combustion Stratification for Naphtha from CI Combustion to PPC

KAUST Repository

Vallinayagam, R.

2017-03-28

This study demonstrates the combustion stratification from conventional compression ignition (CI) combustion to partially premixed combustion (PPC). Experiments are performed in an optical CI engine at a speed of 1200 rpm for diesel and naphtha (RON = 46). The motored pressure at TDC is maintained at 35 bar and fuelMEP is kept constant at 5.1 bar to account for the difference in fuel properties between naphtha and diesel. Single injection strategy is employed and the fuel is injected at a pressure of 800 bar. Photron FASTCAM SA4 that captures in-cylinder combustion at the rate of 10000 frames per second is employed. The captured high speed video is processed to study the combustion homogeneity based on an algorithm reported in previous studies. Starting from late fuel injection timings, combustion stratification is investigated by advancing the fuel injection timings. For late start of injection (SOI), a direct link between SOI and combustion phasing is noticed. At early SOI, combustion phasing depends on both intake air temperature and SOI. In order to match the combustion phasing (CA50) of diesel, the intake air temperature is increased to 90°C for naphtha. The combustion stratification from CI to PPC is also investigated for various level of dilution by displacing oxygen with nitrogen in the intake. The start of combustion (SOC) was delayed with the increase in dilution and to compensate for this, the intake air temperature is increased. The mixture homogeneity is enhanced for higher dilution due to longer ignition delay. The results show that high speed image is initially blue and then turned yellow, indicating soot formation and oxidation. The luminosity of combustion images decreases with early SOI and increased dilution. The images are processed to generate the level of stratification based on the image intensity. The level of stratification is same for diesel and naphtha at various SOI. When O concentration in the intake is decreased to 17.7% and 14

Combustion and emission characteristics of a diesel engine with DME as port premixing fuel under different injection timing

International Nuclear Information System (INIS)

Wang, Ying; Zhao, Yuwei; Xiao, Fan; Li, Dongchang

2014-01-01

Highlights: • Combustion and emission of diesel engine with DME as premixing fuel were examined. • Injection timing has profound effect on HRR of diffusive combustion in PCCI engine. • DME introduction drastically influenced HRR of PCCI combustion, especially for HTR. • Effect of injection timing on emission of PCCI engine is similar to that of DICI engine. - Abstract: This work dealt with the combustion and exhaust performance of a DME premixed charge compression ignition diesel engine. With the port premixing DME, the heat-release process was made up of the premixed charge homogeneous charge compression ignition combustion and diffusion combustion. The in-cylinder fuel injection timing and port premixing DME quantity played the important roles in combustion and emission control. They had little impact on the peak position of heat-release rate (HRR) during LTR phase. However, they had great effects on the peak values and the crank-angle positions corresponding to the HRR peaks during HTR and diffusion combustion phase. The peak value of HRR increased and the crank-angle corresponding to the HRR peak advanced with an incremental DME quantity or an early injection during HTR phase. However, the peak value of HRR dropped with an incremental DME quantity or a late injection during the diffusion combustion phase. p max and T max increased with an incremental DME quantity or an early injection. At the fixed direct-injection timing, BSFC decreased slightly with a rise of DME quantity due to CA50 closer to TDC. At a fixed DME quantity, BSFC was lowest when diesel was injected into cylinder at 7°CA BTDC. Moreover, as more DME was aspirated from port, NO x emissions decreased firstly but this decreasing trend ceased later. Smoke reduced, but CO and HC increased with a rise of DME quantity. Meanwhile, like the conventional DICI operation, NO x increased, but smoke, CO and HC declined with an early direct-injection

Combustion and exhaust emission characteristics of a compression ignition engine using liquefied petroleum gas-Diesel blended fuel

International Nuclear Information System (INIS)

Qi, D.H.; Bian, Y.ZH.; Ma, ZH.Y.; Zhang, CH.H.; Liu, SH.Q.

2007-01-01

Towards the effort of reducing pollutant emissions, especially smoke and nitrogen oxides, from direct injection (DI) Diesel engines, engineers have proposed various solutions, one of which is the use of a gaseous fuel as a partial supplement for liquid Diesel fuel. The use of liquefied petroleum gas (LPG) as an alternative fuel is a promising solution. The potential benefits of using LPG in Diesel engines are both economical and environmental. The high auto-ignition temperature of LPG is a serious advantage since the compression ratio of conventional Diesel engines can be maintained. The present contribution describes an experimental investigation conducted on a single cylinder DI Diesel engine, which has been properly modified to operate under LPG-Diesel blended fuel conditions, using LPG-Diesel blended fuels with various blended rates (0%, 10%, 20%, 30%, 40%). Comparative results are given for various engine speeds and loads for conventional Diesel and blended fuels, revealing the effect of blended fuel combustion on engine performance and exhaust emissions

Effect of oxygen enriched combustion and water–diesel emulsion on the performance and emissions of turbocharged diesel engine

International Nuclear Information System (INIS)

Liang, Youcai; Shu, Gequn; Wei, Haiqiao; Zhang, Wei

2013-01-01

Highlights: • Emulsion is effective to mitigate increased NOx caused by OEC. • OEC and WDE have significant influence on particle mode formation. • OEC and WDE have significant influence on combustion characteristics. • The application potential of combination of OEC and WDE has been proved. - Abstract: Oxygen enriched combustion (OEC) is potential to improve emissions, thermal efficiency and brake power output of diesel engine. The purpose of this investigation is to study whether it is feasible to apply water diesel emulsion to mitigate the increasing NOx caused by OEC with comparable BSFC and power output. Effect of OEC on particle size and number concentration was also analyzed in this paper. Oxygen concentration of intake air varied from 21% to 24% by volume. Water content in tested fuels was 0%, 10%, 20%, and 30% by volume respectively. The result indicated that lower BSFC, higher cylinder pressure and shorter ignition delay were observed when OEC was applied, while opposite trends were found when using WDE. Reduction of PM and NOx can be realized simultaneously by applying OE combined with WDE. Particle number concentration of nucleation mode increases with increasing oxygen concentration, while that of accumulation mode decreases. Optimal operating condition was realized when water content in emulsion was below 20% along with low oxygen enrichment

TECHNICAL AND ENERGY PARAMETERS IMPROVEMENT OF DIESEL LOCOMOTIVES THROUGH THE INTRODUCTION OF AUTOMATED CONTROL SYSTEMS OF A DIESEL

Directory of Open Access Journals (Sweden)

M. I. Kapitsa

2015-04-01

Full Text Available Purpose. Today the issue, connected with diesel traction remains relevant for the majority of industrial enterprises and Ukrainian railways and diesel engine continues to be the subject of extensive research and improvements. Despite the intensive process of electrification, which accompanies Railway Transport of Ukraine the last few years, diesel traction continues to play an important role both in the main and in the industrial railway traction rolling stock. Anyway, all kinds of maneuvering and chores are for locomotives, they are improved and upgraded relentlessly and hourly. This paper is focused on finding the opportunities to improve technical and energy parameters of diesels due to the development of modern control method of the fuel equipment in the diesel engine. Methodology. The proposed method increases the power of locomotives diesel engines in the range of crankshaft rotation (from idle running to maximum one. It was based on approach of mixture ignition timing up to the top «dead» center of piston position. Findings. The paper provides a brief historical background of research in the area of operating cycle in the internal combustion engine (ICE. The factors affecting the process of mixing and its quality were analyzed. The requirements for fuel feed system in to the cylinder and the «weak points» of the process were presented. A variant of the modification the fuel pump drive, which allows approaching to the regulation of fuel feed system from the other hand and to improve it was proposed. Represents a variant of embodiment of the complex system with specification of mechanical features and control circuits. The algorithm of the system operation was presented and its impact on the performance of diesel was made. Originality. The angle regulating system of fuel supply allows automating the process of fuel injection advance angle into the cylinder. Practical value. At implementation the angle regulating system of fuel supply

Soot measurements for diesel and biodiesel spray combustion under high temperature highly diluted ambient conditions

KAUST Repository

Zhang, Ji; Jing, Wei; Roberts, William L.; Fang, Tiegang

2014-01-01

This paper presents the soot temperature and KL factor for biodiesel, namely fatty acid methyl ester (FAME) and diesel fuel combustion in a constant volume chamber using a two-color technique. The KL factor is a parameter for soot concentration

The effects of ethanol addition with waste pork lard methyl ester on performance, emission and combustion characteristics of a diesel engine

Directory of Open Access Journals (Sweden)

John Panneer Selvam Dharmaraj

2014-01-01

Full Text Available In the recent research, as a result of depletion of world petroleum reserves, considerable attention has been focused on the use of different alternative fuels in diesel engines. The present work aims to ensure the possibility of adding ethanol as an additive with animal fat biodiesel that is tested as an alternative fuel for diesel in a CI engine. In this study, biodiesel is obtained from waste pork lard by base-catalyzed transesterification with methanol when potassium hydroxide as catalyst. 2.5%, 5% and 7.5% by volume of ethanol is blended with neat biodiesel in order to improve performance and combustion characteristics of a diesel engine. The experimental work is carried out in a 3.7 kW, single cylinder, naturally aspirated, water cooled, direct injection diesel engine for different loads and at a constant speed of 1500 rpm. The performance, emission and combustion characteristics of biodiesel-ethanol blends are investigated by comparing them with neat biodiesel and standard diesel. The experimental test results showed that the combustion and performance characteristics improved with the increase in percentage of ethanol addition with biodiesel. When compared to neat biodiesel and standard diesel, an increase in brake thermal efficiency of 5.8% and 4.1% is obtained for BEB7.5 blend at full load of the engine. With the increase in percentage of ethanol fraction in the blends, peak cylinder pressure and the corresponding heat release rate are increased. Biodiesel-ethanol blends exhibit longer ignition delay and shorter combustion duration when compared to neat biodiesel. Optimum reduction in carbon monoxide, unburned hydrocarbon and smoke emission are attained while using BEB5 blend at full load of the engine. However, there is an adverse effect in case of nitrogen oxide emission.

Presumptions of effective operation of diesel engines running on rme biodiesel. Research on kinetics of combustion of RME biodiesel

Directory of Open Access Journals (Sweden)

A. Vaicekauskas

2007-06-01

Full Text Available The results of experimental research on kinetics of fuel combustion of diesel engine A41are presented in the publication. The change of characteristics of indicated work (in-cylinder pressure and temperature, period of induction, heat release and heat release rate and fuel injection (fuel injection pressure, fuel injection phases was determined in diesel engine running on RME biodiesel being compared to diesel fuel. The results of researches were used to explain experimentally determined changes of operational and ecological characteristics of diesel engine running on RME biodiesel. In addition, the reliability of diesel engine A41 running on RME biodiesel was evaluated. The presumptions of effective operation of diesel engines running on RME biodiesel were formulated.

Combustion and emissions characteristics of diesel engine fueled by biodiesel at partial load conditions

International Nuclear Information System (INIS)

An, H.; Yang, W.M.; Chou, S.K.; Chua, K.J.

2012-01-01

Highlights: ► Impact of engine load on engine’s performance, combustion and emission characteristics. ► The brake specific fuel consumption (BSFC) increases significantly at partial load conditions. ► The brake thermal efficiency (BTE) drops at lower engine loads, and increases at higher loads. ► The partial load also influences the trend of CO emissions. -- Abstract: This paper investigated the performance, combustion and emission characteristics of diesel engine fueled by biodiesel at partial load conditions. Experiments were conducted on a common-rail fuel injection diesel engine using ultra low sulfur diesel, biodiesel (B100) and their blend fuels of 10%, 20%, 50% (denoted as B10, B20 and B50 respectively) under various loads. The results show that biodiesel/blend fuels have significant impacts on the engine’s brake specific fuel consumption (BSFC) and brake thermal efficiency (BTE) at partial load conditions. The increase in BSFC for B100 is faster than that of pure diesel with the decrease of engine load. A largest increase of 28.1% in BSFC is found at 10% load. Whereas for BTE, the results show that the use of biodiesel results in a reduced thermal efficiency at lower engine loads and improved thermal efficiency at higher engine loads. Furthermore, the characteristics of carbon monoxide (CO) emissions are also changed at partial load conditions. When running at lower engine loads, the CO emission increases with the increase of biodiesel blend ratio and the decrease of engine speed. However, at higher engine loads, an opposite trend is obtained.

Desempeño y emisiones de un motor de combustión interna con combustible dual Diesel – Gas natural ;Performance and emissions study of an internal combustion engine with dual fuel diesel - natural gas

Directory of Open Access Journals (Sweden)

Juan Miguel Mantilla González

2015-04-01

Full Text Available Muchos de los problemas reportados para los sistemas duales diesel- gas natural ocurren por mala dosificación del gas. Por esta razón se adaptó un sistema de alimentación dual con inyección electrónica de gas natural a un motor de combustión interna encendido por compresión. Se plantea un diseño experimental controlando el dosado de gas natural.Como resultado se obtiene un análisis comparativo entre los valoresde desempeño y emisiones desde la operación Diesel y Diesel-Gas natural. A partir de este análisis es posible observar que el desempeño del motor no se ve afectado por la operación del motor bajo el esquema Dual Diesel-GN, es decir que el motor funcionando bajo modo dual puede sostener las cargas solicitadas al motor. También se observa que la eficiencia volumétrica mejora bajo todas las condiciones de operación dual y las emisiones son mejores sólo cuando el motor trabaja a altas cargas. Many of the problems reported for dual diesel-natural gas systems occur due to poor gas dosage. For this reason a natural gas electronic injection feeding system was adapted to a compression ignitios internal combustion engine. An experimental design controlling the natural gas dosage is considered. As a result a comparative analysis between performance and emissions from the Diesel-and diesel-Natural Gas operation is obtained. From this analysis it is possible to see that engine performance is not affected by operation of the engine under the dual mode, i.e. the motor running under dual mode can support the loads applied to the engine. It is also observed that the volumetric efficiency improves under all conditions of operation and emissions from the dual mode of operation are better only when working at high engine loads.

Influencia del porcentaje de mezcla del aceite de higuerilla en la obtención de combustible alternativo para motores diesel

OpenAIRE

Arnoldo Emilio Delgado; Willian Aperador Chaparro; Jorge Réne Silva Gonzalez

2011-01-01

En el presente artículo se describe el uso del aceite de higuerilla como combustible alternativo en motores diesel. Para este fi n, se obtiene biodiesel a partir de aceite de higuerilla mediante el proceso de transesterifi cación. Se prueban tres mezclas de biodiesel (B5%, B10% y B20%) en un motor diesel, para el cual se midieron los siguientes parámetros: la potencia, el consumo de combustible, la temperatura del motor, y los gases de combustión;las mezclas fueron caracterizadas mediante la ...

Performance and combustion analysis of Mahua biodiesel on a single cylinder compression ignition engine using electronic fuel injection system

Directory of Open Access Journals (Sweden)

Gunasekaran Anandkumar

2016-01-01

Full Text Available In this investigation, experiment is carried out on a 1500 rpm constant speed single cylinder Diesel engine. The test is carried out with Neat diesel, neat biodiesel, and blend B20. The engine considered was run with electronic fuel injection system supported by common rail direct injection to obtain high atomization and effective air utilization inside the combustion chamber. The performance of the engine in terms of break thermal efficiency and brake specific energy consumption was found and compared. The B20 blend shows 1.11% decrease in break thermal efficiency and 3.35% increase in brake specific energy consumption than diesel. The combustion characteristics found are in-cylinder pressure, rate of pressure rise, and heat release rate and compared for peak pressure load to understand the nature of combustion process. For each fuel test run, the maximum peak pressure is observed at part load condition. The rate of change of pressure and heat release rate of diesel is high compared to pure biodiesel and B20 blend. The diffusion combustion is observed to be predominant in case of B100 than B20 and Neat diesel.

Evaluation of Emissions Bio diesel

International Nuclear Information System (INIS)

Rodriguez Maroto, J. J.; Dorronsoro Arenal, J. L.; Rojas Garcia, E.; Perez Pastor, R.; Garcia Alonso, S.

2007-01-01

The generation of energy from vegetal products is one of the possibilities to our reach in order to reduce the atmospheric pollution. Particularly, the use of bio diesel in internal combustion engines can be one of the best options. The finest particles emitted by the combustion engines are easily breathable and on them different substances can be absorbed presumably toxic, between which it is possible to emphasize the polycyclic aromatic hydrocarbons (PAHs), by its demonstrated carcinogen character. In this work, it is studied on the one hand, the characteristics that can present the aerosol of emission in a diesel engine with a maximum power of 97 kW, working without load to 600 rpm, using as combustible mixtures of bio diesel and diesel in different proportions. On the other hand, the evolution that takes place in the concentration of PAHs in emission particles, according to the percentage of bio diesel used in the combustible mixture. (Author) 9 refs

Evaluation of Emissions Bio diesel

Energy Technology Data Exchange (ETDEWEB)

Rodriguez Maroto, J J; Dorronsoro Arenal, J L; Rojas Garcia, E; Perez Pastor, R; Garcia Alonso, S

2007-09-27

The generation of energy from vegetal products is one of the possibilities to our reach in order to reduce the atmospheric pollution. Particularly, the use of bio diesel in internal combustion engines can be one of the best options. The finest particles emitted by the combustion engines are easily breathable and on them different substances can be absorbed presumably toxic, between which it is possible to emphasize the polycyclic aromatic hydrocarbons (PAHs), by its demonstrated carcinogen character. In this work, it is studied on the one hand, the characteristics that can present the aerosol of emission in a diesel engine with a maximum power of 97 kW, working without load to 600 rpm, using as combustible mixtures of bio diesel and diesel in different proportions. On the other hand, the evolution that takes place in the concentration of PAHs in emission particles, according to the percentage of bio diesel used in the combustible mixture. (Author) 9 refs.

Optical diagnostics of diesel spray injections and combustion in a high-pressure high-temperature cell

NARCIS (Netherlands)

Bougie, H.J.T.; Tulej, M.; Dreier, T.; Dam, N.J.; Meulen, J.J. ter; Gerber, T.

2005-01-01

We report on spatially and temporally resolved optical diagnostic measurements of propagation and combustion of diesel sprays introduced through a single-hole fuel injector into a constant volume, high-temperature, high-pressure cell. From shadowgraphy images in non-reacting environments of pure

46 CFR 58.10-10 - Diesel engine installations.

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Diesel engine installations. 58.10-10 Section 58.10-10... MACHINERY AND RELATED SYSTEMS Internal Combustion Engine Installations § 58.10-10 Diesel engine installations. (a) The requirements of § 58.10-5 (a), (c), and (d) shall apply to diesel engine installations...

Effect of diesel pre-injection timing on combustion and emission characteristics of compression ignited natural gas engine

International Nuclear Information System (INIS)

Xu, Min; Cheng, Wei; Zhang, Hongfei; An, Tao; Zhang, Shaohua

2016-01-01

Highlights: • Pre-injection timing on combustion and emission of CING engine are studied. • Closely pre-injection operations leads to increase of combustion intensity. • Early pre-injection operations leads to lower combustion intensity. • Early pre-injection modes provide better NO x emission. - Abstract: Pre-injection strategy is considered to be one of the most important ways to improve diesel engine performance, emission and combustion. It is the same important factor in pilot diesel compression ignition natural gas (CING) engine. In this study, effects of pre-injection timing on combustion and emission performances were experimentally studied in a CING engine which was modified from a turbocharged six-cylinder diesel engine. The experiments were conducted at constant speed of 1400 rpm and different engine loads with a constant fuel injection pressure of 1100 bar. Main injection timing was fixed at 10 °CA BTDC in the advance process of pre-injection timing. The cylinder pressure, heart release rate (HRR), pressure rise rate (PRR), start of combustion (SOC) and coefficient of variation (COV IMEP ), as well as NO x , HC and CO emissions were analyzed. The results indicated that closely pre-injection operations lead to the advance of SOC which intensified combustion of in-cylinder mixture, thereby resulting in higher cylinder pressure, HRR and PRR, as well higher NO x emissions and lower HC and CO emissions. However, early pre-injection operations lead to lower cylinder pressure, HRR and PRR due to decreasing in combustion intensity. Pre-injection timing of 70 °CA BTDC is a conversion point in which influence of pre-injection fuel on ignition and combustion of natural gas nearly disappeared and lowest NO x emission could be obtained. Compared with single injection ignition mode, NO x emissions at the conversion point were reduced by 33%, 38% and 7% at engine load of 38%, 60% and 80% respectively. This is important for the conditions that ignition fuel

Auto-Ignition and Combustion of Diesel Fuel in a Constant-Volume Bomb

Science.gov (United States)

Selden, Robert F

1938-01-01

Report presents the results of a study of variations in ignition lag and combustion associated with changes in air temperature and density for a diesel fuel in a constant-volume bomb. The test results have been discussed in terms of engine performance wherever comparisons could be drawn. The most important conclusions drawn from this investigation are: the ignition lag was essentially independent of the injected fuel quantity. Extrapolation of the curves for the fuel used shows that the lag could not be greatly decreased by exceeding the compression-ignition engines. In order to obtain the best combustion and thermal efficiency, it was desirable to use the longest ignition lag consistent with a permissible rate of pressure rise.

Performance, combustion and emission analysis of mustard oil biodiesel and octanol blends in diesel engine

Science.gov (United States)

Devarajan, Yuvarajan; Munuswamy, Dinesh Babu; Nagappan, Beemkumar; Pandian, Amith Kishore

2018-01-01

Biodiesels from the mustard oil promise to be an alternative to the conventional diesel fuel due to their similarity in properties. Higher alcohols are added to neat Mustard oil biodiesel (M100) to vary the properties of biodiesel for improving its combustion, emission and performance characteristics. N-Octanol has the ability to act as an oxygen buffer during combustion which contributes to the catalytic effect and accelerates the combustion process. N-Octanol is dispersed to neat Mustard oil biodiesel in the form of emulsions at different dosage levels of 10, 20 and 30% by volume. Three emulsion fuels prepared for engine testing constitutes of 90% of biodiesel and 10% of n-Octanol (M90O10), 80% of biodiesel and 20% of n-Octanol (M80O20) and 70% of biodiesel and 30% of n-Octanol (M70O30) by volume respectively. AVL 5402 diesel engine is made to run on these fuels to study the effect of n-Octanol on combustion, emission and performance characteristics of the mustard oil biodiesel. Experimental results show that addition of n-octanol has a positive effect on performance, combustion and emission characteristics owing to its inbuilt oxygen content. N-octanol was found to be the better oxidizing catalyst as it was more effective in reducing HC and CO emissions. A significant reduction in NOx emission was found when fuelled with emulsion techniques. The blending of n-octanol to neat Mustard oil biodiesel reduces the energy and fuel consumption and a marginal increase in brake thermal efficiency. Further, n-octanol also reduces the ignition delay and aids the combustion.

Performance, combustion and emission analysis of mustard oil biodiesel and octanol blends in diesel engine

Science.gov (United States)

Devarajan, Yuvarajan; Munuswamy, Dinesh Babu; Nagappan, Beemkumar; Pandian, Amith Kishore

2018-06-01

Biodiesels from the mustard oil promise to be an alternative to the conventional diesel fuel due to their similarity in properties. Higher alcohols are added to neat Mustard oil biodiesel (M100) to vary the properties of biodiesel for improving its combustion, emission and performance characteristics. N-Octanol has the ability to act as an oxygen buffer during combustion which contributes to the catalytic effect and accelerates the combustion process. N-Octanol is dispersed to neat Mustard oil biodiesel in the form of emulsions at different dosage levels of 10, 20 and 30% by volume. Three emulsion fuels prepared for engine testing constitutes of 90% of biodiesel and 10% of n-Octanol (M90O10), 80% of biodiesel and 20% of n-Octanol (M80O20) and 70% of biodiesel and 30% of n-Octanol (M70O30) by volume respectively. AVL 5402 diesel engine is made to run on these fuels to study the effect of n-Octanol on combustion, emission and performance characteristics of the mustard oil biodiesel. Experimental results show that addition of n-octanol has a positive effect on performance, combustion and emission characteristics owing to its inbuilt oxygen content. N-octanol was found to be the better oxidizing catalyst as it was more effective in reducing HC and CO emissions. A significant reduction in NOx emission was found when fuelled with emulsion techniques. The blending of n-octanol to neat Mustard oil biodiesel reduces the energy and fuel consumption and a marginal increase in brake thermal efficiency. Further, n-octanol also reduces the ignition delay and aids the combustion.

Combustion, gaseous and particulate emission of a diesel engine fueled with n-pentanol (C5 alcohol) blended with waste cooking oil biodiesel

International Nuclear Information System (INIS)

Zhu, Lei; Xiao, Yao; Cheung, C.S.; Guan, Chun; Huang, Zhen

2016-01-01

Highlights: • BP blends have fast combustion process at high temperature. • BP blends improve brake thermal efficiency of biodiesel. • Particle mass and number concentration could be reduced by pentanol addition. • Diameter of the primary particle is minimized by pentanol addition. • The addition of 10% pentanol is recommended as a suitable replacement ratio. - Abstract: The combustion, gaseous and particulate emissions of a diesel engine fueled with biodiesel–pentanol (BP) blends were investigated under different engine loads. The results indicate that with the increased pentanol fraction, the start of combustion is delayed. All of the BP blends provide faster combustion than biodiesel and diesel fuel from CA10 to CA90. The faster combustion of BP blends leads to a higher BTE than that of biodiesel and diesel fuel in most cases. The particle mass and number concentrations are reduced by the addition of pentanol in biodiesel in most test conditions, due to the higher oxygen concentration for the fuel/air stoichiometry, longer ignition delay for fuel/air mixing, and lower viscosity for the improvement of atomization. The R−(C=O)O−R′ group in biodiesel is less efficient in suppressing the soot precursor’s formation than the R−OH group in pentanol. The diameter of the primary particles is reduced with the increased addition of pentanol. The particulate emission of BP10 have higher oxidation reactivity that that of BP20 and BP30. Base on this study, pentanol–biodiesel can be considered as an acceptable alternative fuel for diesel engines due to its improved combustion performance and reduced particulate emissions.

Modelling of Combustion and Pollutant Formation in a Large, Two-Stroke Marine Diesel Engine using Integrated CFD-Skeletal Chemical Mechanism

DEFF Research Database (Denmark)

Pang, Kar Mun; Karvounis, Nikolas; Schramm, Jesper

In this reported work, simulation studies of in-cylinder diesel combustion and pollutant formation processesin a two-stroke, low-speed uniflow-scavenged marine diesel engine are presented. Numerical computation is performed by integrating chemical kinetics into CFD computations. In order...... to minimize the computational runtime, an in-house skeletal n-heptane chemical mechanism is coupled with the CFD model. This surrogate fuel model comprises 89 reactions with 32 species essential to diesel ignition/combustion processes as well as the formation of soot precursors and nitrogen monoxide (NO......). Prior to the marine engine simulation,coupling of the newly developed surrogate fuel model and a revised multi-step soot model [1] is validated on the basis of optical diagnostics measurement obtained at varying ambient pressure levels [2]. It is demonstrated that the variation of ignition delay times...

Effects of ambient temperature and oxygen concentration on diesel spray combustion using a single-nozzle injector in a constant volume combustion chamber

KAUST Repository

Jing, Wei

2013-09-02

This work investigates the effects of ambient conditions on diesel spray combustion in an optically accessible, constant volume chamber using a single-nozzle fuel injector. The ambient O2 concentration was varied between five discrete values from 10% to 21% and three different ambient temperatures (800 K, 1000 K, and 1200 K). These conditions simulate different exhaust gas recirculation (EGR) levels and ambient temperatures in diesel engines. Both conventional diesel combustion and low temperature combustion (LTC) modes were observed under these conditions. A transient analysis and a quasi-steady state analysis are employed in this article. The transient analysis focuses on the flame development from beginning to the end, illustrating how the flame structure changes during this process; the quasi-steady state analysis focuses on the stable flame structure. The transient analysis was conducted using high-speed imaging of both OH* chemiluminescence and natural luminosity (NL). In addition, three different images were acquired using an ICCD camera, corresponding to OH* chemiluminescence, narrow-band flame emission at 430 nm (Band A) and at 470 nm (Band B), and were used to investigate the quasi-steady state combustion process. From the transient analysis, it was found that the NL signal becomes stronger and confined to narrow regions when the temperature and O2 concentration increase during the development of flame. The OH* intensity is much lower for the 10% ambient O2 and 800 K conditions compared to the higher temperatures and O2 levels. This implies the occurrence of LTC under these conditions. Results from the quasi-steady combustion stage indicate that high-temperature reactions effectively oxidize the soot in the downstream locations where only OH* signal is observed. In addition, an area was calculated for each spectral region, and results show that the area of Band A and Band B emissions in these images is larger than the area of OH* emissions at the lower O2

Effects of ambient temperature and oxygen concentration on diesel spray combustion using a single-nozzle injector in a constant volume combustion chamber

KAUST Repository

Jing, Wei; Roberts, William L.; Fang, Tiegang

2013-01-01

This work investigates the effects of ambient conditions on diesel spray combustion in an optically accessible, constant volume chamber using a single-nozzle fuel injector. The ambient O2 concentration was varied between five discrete values from 10% to 21% and three different ambient temperatures (800 K, 1000 K, and 1200 K). These conditions simulate different exhaust gas recirculation (EGR) levels and ambient temperatures in diesel engines. Both conventional diesel combustion and low temperature combustion (LTC) modes were observed under these conditions. A transient analysis and a quasi-steady state analysis are employed in this article. The transient analysis focuses on the flame development from beginning to the end, illustrating how the flame structure changes during this process; the quasi-steady state analysis focuses on the stable flame structure. The transient analysis was conducted using high-speed imaging of both OH* chemiluminescence and natural luminosity (NL). In addition, three different images were acquired using an ICCD camera, corresponding to OH* chemiluminescence, narrow-band flame emission at 430 nm (Band A) and at 470 nm (Band B), and were used to investigate the quasi-steady state combustion process. From the transient analysis, it was found that the NL signal becomes stronger and confined to narrow regions when the temperature and O2 concentration increase during the development of flame. The OH* intensity is much lower for the 10% ambient O2 and 800 K conditions compared to the higher temperatures and O2 levels. This implies the occurrence of LTC under these conditions. Results from the quasi-steady combustion stage indicate that high-temperature reactions effectively oxidize the soot in the downstream locations where only OH* signal is observed. In addition, an area was calculated for each spectral region, and results show that the area of Band A and Band B emissions in these images is larger than the area of OH* emissions at the lower O2

Numerical modeling on homogeneous charge compression ignition combustion engine fueled by diesel-ethanol blends

Directory of Open Access Journals (Sweden)

Hanafi H.

2016-01-01

Full Text Available This paper investigates the performance and emission characteristics of HCCI engines fueled with oxygenated fuels (ethanol blend. A modeling study was conducted to investigate the impact of ethanol addition on the performance, combustion and emission characteristics of a Homogeneous Charge Compression Ignition (HCCI engine fueled by diesel. One dimensional simulation was conducted using the renowned commercial software for diesel and its blend fuels with 5% (E5 and 10% ethanol (E10 (in vol. under full load condition at variable engine speed ranging from 1000 to 2750 rpm with 250 rpm increment. The model was then validated with other researcher’s experimental result. Model consists of intake and exhaust systems, cylinder, head, valves and port geometries. Performance tests were conducted for volumetric efficiency, brake engine torque, brake power, brake mean effective pressure, brake specific fuel consumption, and brake thermal efficiency, while exhaust emissions were analyzed for carbon monoxide (CO and unburned hydrocarbons (HC. The results showed that blending diesel with ethanol increases the volumetric efficiency, brake specific fuel consumption and brake thermal efficiency, while it decreases brake engine torque, brake power and brake mean effective pressure. In term of emission characteristics, the CO emissions concentrations in the engine exhaust decrease significantly with ethanol as additive. But for HC emission, its concentration increase when apply in high engine speed. In conclusion, using Ethanol as fuel additive blend with Diesel operating in HCCI shows a good result in term of performance and emission in low speed but not recommended to use in high speed engine. Ethanol-diesel blends need to researched more to make it commercially useable.

Combustion and emission characteristics of a natural gas-fueled diesel engine with EGR

International Nuclear Information System (INIS)

Abdelaal, M.M.; Hegab, A.H.

2012-01-01

Highlights: ► An existed DI diesel engine has been modified to suit dual fuel operation with EGR. ► Comparative study has been conducted between different operating modes. ► Dual fuel mode exhibits better performance at high loads than diesel. ► Dual fuel mode exhibits lower NOx and higher HC emissions than diesel. ► EGR improves performance at part loads and emissions of dual fuel mode. - Abstract: The use of natural gas as a partial supplement for liquid diesel fuel is a very promising solution for reducing pollutant emissions, particularly nitrogen oxides (NOx) and particulate matters (PM), from conventional diesel engines. In most applications of this technique, natural gas is inducted or injected in the intake manifold to mix uniformly with air, and the homogenous natural gas–air mixture is then introduced to the cylinder as a result of the engine suction. This type of engines, referred to as dual-fuel engines, suffers from lower thermal efficiency and higher carbon monoxide (CO) and unburned hydrocarbon (HC) emissions; particularly at part load. The use of exhaust gas recirculation (EGR) is expected to partially resolve these problems and to provide further reduction in NOx emission as well. In the present experimental study, a single-cylinder direct injection (DI) diesel engine has been properly modified to run on dual-fuel mode with natural gas as a main fuel and diesel fuel as a pilot, with the ability to employ variable amounts of EGR. Comparative results are given for various operating modes; conventional diesel mode, dual-fuel mode without EGR, and dual-fuel mode with variable amounts of EGR, at different operating conditions; revealing the effect of utilization of EGR on combustion process and exhaust emission characteristics of a pilot ignited natural gas diesel engine.

Combustion and emission response of a heavy duty diesel engine fuelled with biodiesel: an experimental study

International Nuclear Information System (INIS)

Shah, A.N.; Shan, G.Y.

2010-01-01

In order to meet the growing energy needs, alternative energy sources particularly bio fuels are receiving increasing attention during the last few years. Biodiesel, consisting of alkyl monoesters of fatty acids from vegetable oils or animal fats, has already been commercialized in the transport sector. In the present work, a turbo charged, inter cooled, DI (Direct Injection) diesel engine was fuelled with biodiesel from waste cooking oil and its 20% blend with commercial diesel to study the regulated exhaust pollutants in the light of combustion parameters in the cylinder. The experimental results show that BTE (Brake Thermal Efficiently), MCP (Maximum Combustion Pressure) and SOI (Start of injection) angle were increased, ID (Ignition Delay) was decreased; however, RHR (Rate of Heat Release) remained almost unaffected in case of biodiesel. The BTE and RHR were not much affected with B20; however Sol angle and MCP were improved, and ID was decreased with B20. Smoke opacity, CO (Carbon Monoxide), and HC (HydroCarbons) emissions were decreased, but NO. (Oxides of Nitrogen) pollutants were increased in case of both B100 and B20 compared to fossil diesel. However, the increase in NO emissions was lower with B20. (author)

Development of Advanced In-Cylinder Components and Tribological Systems for Low Heat Rejection Diesel Engines

Science.gov (United States)

Yonushonis, T. M.; Wiczynski, P. D.; Myers, M. R.; Anderson, D. D.; McDonald, A. C.; Weber, H. G.; Richardson, D. E.; Stafford, R. J.; Naylor, M. G.

1999-01-01

In-cylinder components and tribological system concepts were designed, fabricated and tested at conditions anticipated for a 55% thermal efficiency heavy duty diesel engine for the year 2000 and beyond. A Cummins L10 single cylinder research engine was used to evaluate a spherical joint piston and connecting rod with 19.3 MPa (2800 psi) peak cylinder pressure capability, a thermal fatigue resistant insulated cylinder head, radial combustion seal cylinder liners, a highly compliant steel top compression ring, a variable geometry turbocharger, and a microwave heated particulate trap. Components successfully demonstrated in the final test included spherical joint connecting rod with a fiber reinforced piston, high conformability steel top rings with wear resistant coatings, ceramic exhaust ports with strategic oil cooling and radial combustion seal cylinder liner with cooling jacket transfer fins. A Cummins 6B diesel was used to develop the analytical methods, materials, manufacturing technology and engine components for lighter weight diesel engines without sacrificing performance or durability. A 6B diesel engine was built and tested to calibrate analytical models for the aluminum cylinder head and aluminum block.

Effects of Oxygen Content of Fuels on Combustion and Emissions of Diesel Engines

Directory of Open Access Journals (Sweden)

Haiwen Song

2016-01-01

Full Text Available Effects of oxygen content of fuels on combustion characteristics and emissions were investigated on both an optical single cylinder direct injection (DI diesel engine and a multi-cylinder engine. Three fuels were derived from conventional diesel fuel (Finnish City diesel summer grade by blending Rapeseed Methyl Ester (RME or Diglyme and Butyl-Diglyme of different quantities to make their oxygen content 3%, 3% and 9%, respectively. The experimental results with three tested fuels show that the fuel spray development was not affected apparently by the oxygenating. Compared with the base fuel, the ignition delay to pilot injection was shortened by 0%, 11% and 19% for three oxygenated fuels, respectively. The ignition delay to main injection was shortened by 10%, 19% and 38%, respectively. With regard to emissions, the smoke level was reduced by 24% to 90%, depending on fuel properties and engine running conditions. The penalties of increased NOx emissions and fuel consumption were up to 19% and 24%, respectively.

Experimental investigation of the impact of using alcohol- biodiesel-diesel blending fuel on combustion of single cylinder CI engine

Science.gov (United States)

Mahmudul, H. M.; Hagos, Ftwi Y.; Mamat, Rizalman; Abdullah, Abdul A.; Awad, Omar. I.

2016-11-01

The effect of alcohol addition has been experimentally in vestgated in the current study by blending it with diesel and palm based biodiesel on the combustion of a compression ignition engine. The experiment was run by single-cylinder, naturally aspirated, direct injection, four-stroke diesel engine. Based on the pressure-crank angle data collected from the pressure transducer and crank angle encoder, the combustion analysis such as incylinder pressure, incylinder temperature, energy release rate, cumulative energy release and ignition delay are analysed. In this comparative study, the effects of alcohols namely butanol BU20 (20% butanol addition on the commercially available diesel biodiesel emulsion) is compared and evaluated with pure diesel (D100). The results revealed that the the ignition delay for BU20 is longer as compared to that of D100 in all engine speeds and loads compared. Besides, the incylinder temperatures were rudecued with the butanol addition. The energy release rate for BU20 was higher than that for diesel, whereas the peak positions concerning the energy release rate for BU20 was discovered at 2400 rpm. Therefore addition of butanol will have positive role on the NOx emissions and stability of the engine due to its higher latent heat of vaporization.

IN-SITU Optical Diagnostics Of Diesel Spray Injection And Combustion For Engine-Like Conditions

Energy Technology Data Exchange (ETDEWEB)

Bougie, B.; Tulej, M.; Dreier, T.; Gerber, T.

2004-03-01

A combination of shadowgraphy, laser elastic scattering, laser-induced incandescence and chemiluminescence imaging was conducted to characterize the propagation, vaporization and soot formation due to combustion of Diesel fuel injection into a hot (550-850 K), high pressure (4-6 MPa) gaseous environment as provided by the PSI high temperature pressure vessel (HTDZ). (author)

Emission potentials of future diesel fuel injection systems; Emissionspotentiale zukuenftiger Diesel-Einspritzsysteme

Energy Technology Data Exchange (ETDEWEB)

Schommers, J.; Breitbach, H.; Stotz, M.; Schnabel, M. [DaimlerChrysler AG (Germany)

2007-07-01

the direct driven injector in all criteria. The analysis of the concepts on engine confirmed the superior results with regard to emissions, engine power and noise. A detailed analysis of the combustion process and an analysis of the in nozzle flow reveals the physics behind these positive results. With its excellent rate of injection shape, its robustness and stability, the direct driven injector is an attractive fuel injection system, creating excellent conditions to meet the ambitions development targets of future Mercedes-Benz diesel engines. (orig.)

Numerical Studies on Controlling Gaseous Fuel Combustion by Managing the Combustion Process of Diesel Pilot Dose in a Dual-Fuel Engine

Directory of Open Access Journals (Sweden)

Mikulski Maciej

2015-06-01

Full Text Available Protection of the environment and counteracting global warming require finding alternative sources of energy. One of the methods of generating energy from environmentally friendly sources is increasing the share of gaseous fuels in the total energy balance. The use of these fuels in compression-ignition (CI engines is difficult due to their relatively high autoignition temperature. One solution for using these fuels in CI engines is operating in a dualfuel mode, where the air and gas mixture is ignited with a liquid fuel dose. In this method, a series of relatively complex chemical processes occur in the engine's combustion chamber, related to the combustion of individual fuel fractions that interact with one another. Analysis of combustion of specific fuels in this type of fuel injection to the engine is difficult due to the fact that combustion of both fuel fractions takes place simultaneously. Simulation experiments can be used to analyse the impact of diesel fuel combustion on gaseous fuel combustion. In this paper, we discuss the results of simulation tests of combustion, based on the proprietary multiphase model of a dual-fuel engine. The results obtained from the simulation allow for analysis of the combustion process of individual fuels separately, which expands the knowledge obtained from experimental tests on the engine.

A study on the 0D phenomenological model for diesel engine simulation: Application to combustion of Neem methyl esther biodiesel

International Nuclear Information System (INIS)

Ngayihi Abbe, Claude Valery; Nzengwa, Robert; Danwe, Raidandi; Ayissi, Zacharie Merlin; Obonou, Marcel

2015-01-01

Highlights: • We elaborate a 0D model for prediction of diesel engine operating parameters. • We implement the model for Neem methyl ester biodiesel combustion. • We show methyl butanoate and butyrate can be used as surrogates for biodiesel. • The model predicts fuel spray, in cylinder gaseous state and NOx emissions. • We show the model can be effective both in accuracy and computational speed. - Abstract: The design and monitoring of modern diesel engines running on alternative fuels require reliable models that can validly substitute experimental tests and predict their operating characteristics under different load conditions. Although there exists a multitude of models for diesel engines, 0D phenomenological models present the advantages of giving fast and accurate computed results. These models are useful for predicting fuel spray characteristics and instantaneous gas state. However, there are few reported studies on the application of 0D phenomenological models on biodiesel fuel combustion in diesel engines. This work reports the elaboration, validation and application on Neem methyl ester biodiesel (NMEB) combustion of a 0D phenomenological model for diesel engine simulation. The model addresses some specific aspects of diesel engine modeling found in previous studies such as the compromise between computers cost, accurateness and model simplicity, the reduction of the number of empirical fitting constant, the prediction of combustion kinetics with reduction of the need of experimental curve fitting, the ability to simultaneously predict under various loads engine thermodynamic and spray parameters as well as emission characteristics and finally the ability to simulate diesel engine parameters when fueled by alternative fuels. The proposed model predicts fuel spray behavior, in cylinder combustion and nitric oxides (NOx) emissions. The model is implemented through a Matlab code. The model is mainly based on Razlejtsev’s spray evaporation model

Evaluation of carcinogenic hazard of diesel engine exhaust needs to consider revolutionary changes in diesel technology.

Science.gov (United States)

McClellan, Roger O; Hesterberg, Thomas W; Wall, John C

2012-07-01

Diesel engines, a special type of internal combustion engine, use heat of compression, rather than electric spark, to ignite hydrocarbon fuels injected into the combustion chamber. Diesel engines have high thermal efficiency and thus, high fuel efficiency. They are widely used in commerce prompting continuous improvement in diesel engines and fuels. Concern for health effects from exposure to diesel exhaust arose in the mid-1900s and stimulated development of emissions regulations and research to improve the technology and characterize potential health hazards. This included epidemiological, controlled human exposure, laboratory animal and mechanistic studies to evaluate potential hazards of whole diesel exhaust. The International Agency for Research on Cancer (1989) classified whole diesel exhaust as - "probably carcinogenic to humans". This classification stimulated even more stringent regulations for particulate matter that required further technological developments. These included improved engine control, improved fuel injection system, enhanced exhaust cooling, use of ultra low sulfur fuel, wall-flow high-efficiency exhaust particulate filters, exhaust catalysts, and crankcase ventilation filtration. The composition of New Technology Diesel Exhaust (NTDE) is qualitatively different and the concentrations of particulate constituents are more than 90% lower than for Traditional Diesel Exhaust (TDE). We recommend that future reviews of carcinogenic hazards of diesel exhaust evaluate NTDE separately from TDE. Copyright © 2012 Elsevier Inc. All rights reserved.

Acoustic measurements for the combustion diagnosis of diesel engines fuelled with biodiesels

Science.gov (United States)

Zhen, Dong; Wang, Tie; Gu, Fengshou; Tesfa, Belachew; Ball, Andrew

2013-05-01

In this paper, an experimental investigation was carried out on the combustion process of a compression ignition (CI) engine running with biodiesel blends under steady state operating conditions. The effects of biodiesel on the combustion process and engine dynamics were analysed for non-intrusive combustion diagnosis based on a four-cylinder, four-stroke, direct injection and turbocharged diesel engine. The signals of vibration, acoustic and in-cylinder pressure were measured simultaneously to find their inter-connection for diagnostic feature extraction. It was found that the sound energy level increases with the increase of engine load and speed, and the sound characteristics are closely correlated with the variation of in-cylinder pressure and combustion process. The continuous wavelet transform (CWT) was employed to analyse the non-stationary nature of engine noise in a higher frequency range. Before the wavelet analysis, time synchronous average (TSA) was used to enhance the signal-to-noise ratio (SNR) of the acoustic signal by suppressing the components which are asynchronous. Based on the root mean square (RMS) values of CWT coefficients, the effects of biodiesel fractions and operating conditions (speed and load) on combustion process and engine dynamics were investigated. The result leads to the potential of airborne acoustic measurements and analysis for engine condition monitoring and fuel quality evaluation.

Acoustic measurements for the combustion diagnosis of diesel engines fuelled with biodiesels

International Nuclear Information System (INIS)

Zhen, Dong; Gu, Fengshou; Tesfa, Belachew; Ball, Andrew; Wang, Tie

2013-01-01

In this paper, an experimental investigation was carried out on the combustion process of a compression ignition (CI) engine running with biodiesel blends under steady state operating conditions. The effects of biodiesel on the combustion process and engine dynamics were analysed for non-intrusive combustion diagnosis based on a four-cylinder, four-stroke, direct injection and turbocharged diesel engine. The signals of vibration, acoustic and in-cylinder pressure were measured simultaneously to find their inter-connection for diagnostic feature extraction. It was found that the sound energy level increases with the increase of engine load and speed, and the sound characteristics are closely correlated with the variation of in-cylinder pressure and combustion process. The continuous wavelet transform (CWT) was employed to analyse the non-stationary nature of engine noise in a higher frequency range. Before the wavelet analysis, time synchronous average (TSA) was used to enhance the signal-to-noise ratio (SNR) of the acoustic signal by suppressing the components which are asynchronous. Based on the root mean square (RMS) values of CWT coefficients, the effects of biodiesel fractions and operating conditions (speed and load) on combustion process and engine dynamics were investigated. The result leads to the potential of airborne acoustic measurements and analysis for engine condition monitoring and fuel quality evaluation. (paper)

An investigation of the engine performance, emissions and combustion characteristics of coconut biodiesel in a high-pressure common-rail diesel engine

International Nuclear Information System (INIS)

How, H.G.; Masjuki, H.H.; Kalam, M.A.; Teoh, Y.H.

2014-01-01

An experimental investigation on engine performance, emissions, combustion and vibration characteristics with coconut biodiesel fuels was conducted in a high-pressure common-rail diesel engine under five different load operations (0.17, 0.34, 0.52, 0.69 and 0.86 MPa). The test fuels included a conventional diesel fuel and four different fuel blends of coconut biodiesel (B10, B20, B30 and B50). The results showed that biodiesel blended fuels have significant influences on the BSFC (brake specific fuel consumption) and BSEC (brake specific energy consumption) at all engine loads. In general, the use of coconut biodiesel blends resulted in a reduction of BSCO (brake specific carbon monoxide) and smoke emissions regardless of the load conditions. A large reduction of 52.4% in smoke opacity was found at engine load of 0.86 MPa engine load with B50. For combustion characteristics, a slightly shorter ignition delay and longer combustion duration were found with the use of biodiesel blends under all loading operations. It was found that generally the biodiesel blends produced lower peak heat release rate than baseline diesel. The vibration results showed that the largest reduction of 13.7% in RMS (root mean square) of acceleration was obtained with B50 at engine load of 0.86 MPa with respect to the baseline diesel. - Highlights: • The performance, emissions and combustion characteristics of biodiesel were studied. • A tangible increase in BSFC was observed at all engine loads with coconut biodiesel. • A slightly shorter ignition delay was found with the use of biodiesel blends. • The vibrations for coconut biodiesel blends in diesel engine were investigated. • B50 achieved the largest reduction in RMS of acceleration at 0.86 MPa engine load

In-cylinder diesel spray combustion simulations using parallel computation: A performance benchmarking study

International Nuclear Information System (INIS)

Pang, Kar Mun; Ng, Hoon Kiat; Gan, Suyin

2012-01-01

Highlights: ► A performance benchmarking exercise is conducted for diesel combustion simulations. ► The reduced chemical mechanism shows its advantages over base and skeletal models. ► High efficiency and great reduction of CPU runtime are achieved through 4-node solver. ► Increasing ISAT memory from 0.1 to 2 GB reduces the CPU runtime by almost 35%. ► Combustion and soot processes are predicted well with minimal computational cost. - Abstract: In the present study, in-cylinder diesel combustion simulation was performed with parallel processing on an Intel Xeon Quad-Core platform to allow both fluid dynamics and chemical kinetics of the surrogate diesel fuel model to be solved simultaneously on multiple processors. Here, Cartesian Z-Coordinate was selected as the most appropriate partitioning algorithm since it computationally bisects the domain such that the dynamic load associated with fuel particle tracking was evenly distributed during parallel computations. Other variables examined included number of compute nodes, chemistry sizes and in situ adaptive tabulation (ISAT) parameters. Based on the performance benchmarking test conducted, parallel configuration of 4-compute node was found to reduce the computational runtime most efficiently whereby a parallel efficiency of up to 75.4% was achieved. The simulation results also indicated that accuracy level was insensitive to the number of partitions or the partitioning algorithms. The effect of reducing the number of species on computational runtime was observed to be more significant than reducing the number of reactions. Besides, the study showed that an increase in the ISAT maximum storage of up to 2 GB reduced the computational runtime by 50%. Also, the ISAT error tolerance of 10 −3 was chosen to strike a balance between results accuracy and computational runtime. The optimised parameters in parallel processing and ISAT, as well as the use of the in-house reduced chemistry model allowed accurate

Effects of ambient oxygen concentration on soot temperature and concentration for biodiesel and diesel spray combustion

KAUST Repository

Zhang, Ji

2015-06-01

Ambient oxygen concentration, a key variable directly related to exhaust gas recirculation (EGR) levels in diesel engines, plays a significant role in particulate matter (PM) and nitrogen oxides (NOx) emissions. The utilization of biodiesel in diesel engines has been investigated over the last decades for its renewable characteristics and lower emissions compared to diesel. In an earlier work, we demonstrated that the soot temperature and concentration of biodiesel were lower than diesel under regular diesel engine conditions without EGR. Soot concentration was quantified by a parameter called KL factor. As a continuous effort, this paper presents an experimental investigation of the ambient oxygen concentration on soot temperature and KL factor during biodiesel and diesel spray combustion. The experiment was implemented in a constant volume chamber system, where the ambient oxygen concentration varied from 21 to 10% and the ambient temperature was kept to 1,000 K. A high speed two-color pyrometry technique was used to measure transient soot temperature and the KL factor of the spray flame. The soot temperature of biodiesel is found to be lower than that of diesel under the same conditions, which follows the same trend from our previous results found when the ambient temperature changes to 21% oxygen conditions. A reduction in ambient oxygen concentration generally reduces the soot temperature for both fuels. However, this is a complicated effect on soot processes as the change of oxygen concentration greatly affects the balance between soot formation and oxidation. The KL factor is observed to be the highest at 12% O2 for diesel and 18% O2 for biodiesel, respectively. On the other hand, the 10% O2 condition shows the lowest KL factor for both fuels. These results can provide quantitative experimental evidences to optimize the ambient oxygen concentration for diesel engines using different fuels for better emissions characteristics. © 2014 American Society of

Stationary engine test of diesel cycle using diesel oil and biodiesel (B100); Ensaio de motores estacionarios do ciclo diesel utilizando oleo diesel e biodiesel (B100)

Energy Technology Data Exchange (ETDEWEB)

Torres, Ednildo Andrade [Universidade Federal da Bahia (DEQ/DEM/EP/UFBA), Salvador, BA (Brazil). Escola Politecnica. Dept. de Engenharia Quimica], Email: ednildo@ufba.br; Santos, Danilo Cardoso [Universidade Federal da Bahia (PPEQ/UFBA), Salvador, BA (Brazil). Programa de Pos-Graduacao em Engenharia Quimica; Souza, Daniel Vidigal D.; Peixoto, Leonardo Barbosa; Franca, Tiago [Universidade Federal da Bahia (DEM/UFBA), Salvador, BA (Brazil). Dept. de Engenharia Mecanica

2006-07-01

This work objectified to test an engine stationary of the cycle diesel, having as combustible diesel fossil and bio diesel. The characteristic curves of power, torque and emissions versus rotation of the engine was elaborated. The survey of these curves was carried through in the Laboratorio de Energia e Gas da Escola Politecnica da UFBA, which makes use of two stationary dynamometers and the one of chassis and necessary instrumentation for you analyze of the exhaustion gases. The tested engine was of the mark AGRALE, M-85 model stationary type, mono cylinder, with power NF (NBRISO 1585) Cv/kw/rpm 10/7,4/2500. The assays had been carried through in a hydraulically dynamometer mark Schenck, D-210 model. The fuel consumption was measured in a scale marks Filizola model BP-6, and too much ground handling equipment such as: water reservoir, tubings, valves controllers of volumetric outflow, sensors and measurers of rotation, torque, mass, connected to a system of acquisition of data on line. The emissions of the gases (CO, CO{sub 2}, and NOx), were measured by the analytical Tempest mark, model 100. The engine operated with oil diesel and bio diesel of oils and residual fats (OGR). In the tests, the use of the fuel derived from oil and the gotten ones from OGR was not detected significant differences how much. In this phase already it can show to the immediate possibility of the substitution of the oil diesel for bio diesel as combustible in the stationary engines of low power (author)

Investigation into the effect of different fuels on ignition delay of M-type diesel combustion process

Directory of Open Access Journals (Sweden)

Bibić Dževad

2008-01-01

Full Text Available 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.

Diesel/CNG Mixture Autoignition Control Using Fuel Composition and Injection Gap

Directory of Open Access Journals (Sweden)

Firmansyah

2017-10-01

Full Text Available Combustion phasing is the main obstacle to the development of controlled auto-ignition based (CAI engines to achieve low emissions and low fuel consumption operation. Fuel combinations with substantial differences in reactivity, such as diesel/compressed natural gas (CNG, show desirable combustion outputs and demonstrate great possibility in controlling the combustion. This paper discusses a control method for diesel/CNG mixture combustion with a variation of fuel composition and fuel stratification levels. The experiments were carried out in a constant volume combustion chamber with both fuels directly injected into the chamber. The mixture composition was varied from 0 to 100% CNG/diesel at lambda 1 while the fuel stratification level was controlled by the injection phasing between the two fuels, with gaps between injections ranging from 0 to 20 ms. The results demonstrated the suppressing effect of CNG on the diesel combustion, especially at the early combustion stages. However, CNG significantly enhanced the combustion performance of the diesel in the later stages. Injection gaps, on the other hand, showed particular behavior depending on mixture composition. Injection gaps show less effect on combustion phasing but a significant effect on the combustion output for higher diesel percentage (≥70%, while it is contradictive for lower diesel percentage (<70%.

Optimization of combustion chamber geometry for natural gas engines with diesel micro-pilot-induced ignition

International Nuclear Information System (INIS)

Wang, Bin; Li, Tie; Ge, Linlin; Ogawa, Hideyuki

2016-01-01

Highlights: • Combustion chamber geometry is optimized to reduce the HC/CO emissions. • CFD model is calibrated against the spray visualization and engine bench test data. • Design space is explored by the multi-objective NSGA-II with Kriging meta-model. • HC and CO emissions are respectively reduced by 56.47% and 33.55%. - Abstract: Smokeless, low nitrogen oxides (NOx), and high thermal efficiency have been achieved through the lean-burn concept for natural gas engine with diesel micro-pilot-induced ignition (MPII). However, the combustion chamber is usually not specialized for natural gas combustion, and increases in the unburned hydrocarbon (HC) and carbon monoxide (CO) emissions are still a challenge for this type of engines. This paper describes optimization of the combustion chamber geometry to reduce the HC and CO emissions and improve the combustion efficiency in the MPII natural gas engine. The 3-D computational fluid dynamics (CFD) simulation model coupled with a chemical reaction mechanism is described. The temporal development of the short-pulsed diesel spray in a high pressure constant-volume vessel is measured and used to calibrate the spray model in the CFD simulation. The simulation models are validated by the experimental data of the in-cylinder pressure trace, apparent heat release rate (AHRR) and exhaust gas emissions from a single-cylinder MPII natural gas engine. To generate the various combustion chamber geometries, the bowl outline is parameterized by the two cubic Bezier curves while keeping the compression ratio constant. The available design space is explored by the multi-objective non-dominated sorting genetic algorithm II (NSGA-II) with Kriging-based meta-model. With the optimization, the HC and CO emissions are reduced by 56.47% and 33.55%, respectively, while the NOx emissions, the maximum rate of pressure rise and the gross indicated thermal efficiency that are employed as the constraints are slightly improved. Finally, the

Desempenho de motor ciclo Diesel em bancada dinamométrica utilizando misturas diesel/biodiesel Performance of cycle Diesel engine in dynamometer using diesel/biodiesel mixtures

Directory of Open Access Journals (Sweden)

Marcio Castellanelli

2008-03-01

Full Text Available Diante da previsão de escassez do petróleo, o éster etílico (biodiesel tem-se apresentado como excelente opção de combustível alternativo para motores ciclo Diesel. As características do biodiesel são semelhantes às do diesel em termos de viscosidade e poder calorífico, podendo ser utilizado sem adaptações nos motores. Para a realização deste trabalho, utilizou-se de motor ciclo Diesel, de injeção direta, com quatro cilindros, sem adaptações. O motor foi acoplado a um dinamômetro e sistemas de aquisição de dados auxiliares. Avaliaram-se os desempenhos de torque, de potência e de consumo específico de combustível para as seguintes misturas diesel/éster etílico de soja: B2, B5, B10, B20, B50, B75 e B100. O melhor desempenho registrado deu-se com a mistura B20.Given the prediction of the scarcity of oil, the ethyl ester (biodiesel has presented as an excellent alternative fuel option for cycle diesel engine. The characteristics of biodiesel are similar of diesel in terms of viscosity and the calorific power, being able to be used without adaptations in the engines. For the accomplishment of this work it was used a cycle diesel engine, of direct injection with four cylinders, without adaptations. The engine was connected to a dynamometer and acquisition systems of auxiliary data. The performances of torque, power and specific fuel consumption for the following mixtures diesel/soy ethyl ester had been evaluated: B2, B5, B10, B20, B50, B75 and B100. The best registered performance was given with the B20 mixture.

Pressure-time characteristics in diesel engine fueled with natural gas

Energy Technology Data Exchange (ETDEWEB)

Selim, Mohamed Y.E. [Helwan Univ., Mechanical Power Engineering Dept., Cairo (Egypt)

2001-04-01

Combustion pressure data are measured and presented for a dual fuel engine running on dual fuel of diesel and compressed natural gas, and compared to the diesel engine case. The maximum pressure rise rate during combustion is presented as a measure of combustion noise. Experimental investigation on diesel and dual fuel engines revealed the noise generated from combustion in both cases. A Ricardo E6 diesel version engine is converted to run on dual fuel of diesel and compressed natural gas and is used throughout the work. The engine is fully computerized and the cylinder pressure data, crank angle data are stored in a PC for off-line analysis. The effect of engine speeds, loads, pilot injection angle, and pilot fuel quantity on combustion noise is examined for both diesel and dual engine. Maximum pressure rise rate and some samples of ensemble averaged pressure-crank angle data are presented in the present work. The combustion noise, generally, is found to increase for the dual fuel engine case as compared to the diesel engine case. (Author)

Development of a robust and compact kerosene–diesel reaction mechanism for diesel engines

International Nuclear Information System (INIS)

Tay, Kun Lin; Yang, Wenming; Mohan, Balaji; An, Hui; Zhou, Dezhi; Yu, Wenbin

2016-01-01

Highlights: • An approach is used to develop a robust kerosene–diesel reaction mechanism. • Ignition delay of the kerosene sub-mechanism is well validated with experiments. • The kerosene sub-mechanism reproduces the flame lift-off lengths of Jet-A reasonably well. • The kerosene sub-mechanism performs reasonably well under engine conditions. - Abstract: The use of kerosene fuels in internal combustion engines is getting more widespread. The North Atlantic Treaty Organization military is pushing for the use of a single fuel on the battlefield in order to reduce logistical issues. Moreover, in some countries, fuel adulteration is a serious matter where kerosene is blended with diesel and used in diesel engines. So far, most investigations done regarding the use of kerosene fuels in diesel engines are experimental and there is negligible simulation work done in this area possibly because of the lack of a robust and compact kerosene reaction mechanism. This work focuses on the development of a small but reliable kerosene–diesel reaction mechanism, suitable to be used for diesel engine simulations. The new kerosene–diesel reaction mechanism consists only of 48 species and 152 reactions. Furthermore, the kerosene sub-mechanism in this new mechanism is well validated for its ignition delay times and has proven to replicate kerosene combustion well in a constant volume combustion chamber and an optical engine. Overall, this new kerosene–diesel reaction mechanism is proven to be robust and practical for diesel engine simulations.

The effect of ethanol–diesel–biodiesel blends on combustion, performance and emissions of a direct injection diesel engine

International Nuclear Information System (INIS)

Labeckas, Gvidonas; Slavinskas, Stasys; Mažeika, Marius

2014-01-01

Highlights: • Ethanol–diesel–biodiesel blends were tested at the same air–fuel ratios and three ranges of speed. • The fuel oxygen mass content reflects changes in the autoignition delay more predictably than the cetane number does. • Using of composite blend E15B suggests the brake thermal efficiency the same as the normal diesel fuel. • Adding of ethanol to diesel fuel reduces the NO x emission for richer air–fuel mixtures at all engine speeds. • The ethanol effect on CO, HC emissions and smoke opacity depends on the air–fuel ratio and engine speed. - Abstract: The article presents the test results of a four-stroke, four-cylinder, naturally aspirated, DI 60 kW diesel engine operating on diesel fuel (DF) and its 5 vol% (E5), 10 vol% (E10), and 15 vol% (E15) blends with anhydrous (99.8%) ethanol (E). An additional ethanol–diesel–biodiesel blend E15B was prepared by adding the 15 vol% of ethanol and 5 vol% of biodiesel (B) to diesel fuel (80 vol%). The purpose of the research was to examine the influence of the ethanol and RME addition to diesel fuel on start of injection, autoignition delay, combustion and maximum heat release rate, engine performance efficiency and emissions of the exhaust when operating over a wide range of loads and speeds. The test results were analysed and compared with a base diesel engine running at the same air–fuel ratios of λ = 5.5, 3.0 and 1.5 corresponding to light, medium and high loads. The same air–fuel ratios predict that the energy content delivered per each engine cycle will be almost the same for various ethanol–diesel–biodiesel blends that eliminate some side effects and improve analyses of the test results. A new approach revealed an important role of the fuel bound oxygen, which reflects changes of the autoignition delay more predictably than the cetane number does. The influence of the fuel oxygen on maximum heat release rate, maximum combustion pressure, NO x , CO emissions and smoke opacity

Electrical diesel particulate filter (DPF) regeneration

Science.gov (United States)

Gonze, Eugene V; Ament, Frank

2013-12-31

An exhaust system that processes exhaust generated by an engine includes a diesel particulate filter (DPF) that is disposed downstream of the engine and that filters particulates from the exhaust. An electrical heater is disposed upstream of the DPF and selectively heats the exhaust to initiate combustion of the particulates within the exhaust as it passes therethrough. Heat generated by combustion of the particulates induces combustion of particulates within the DPF.

Cobalt and KNO3 supported on alumina catalysts for diesel soot combustion

International Nuclear Information System (INIS)

Grzona, Claudia B.; Lick, Ileana D.; Castellon, Enrique Rodriguez; Ponzi, Marta I.; Ponzi, Esther N.

2010-01-01

The catalytic combustion of diesel soot was studied in the presence of fresh and aged catalysts: Co/Al 2 O 3 , KNO 3 /Al 2 O 3 and Co/KNO 3 /Al 2 O 3 . The catalysts were prepared by impregnation using nitrate solutions. The catalysts were characterized by X-ray diffraction, thermal programmed reduction, vibrational spectroscopy and X-ray photoelectron spectroscopy. Fresh and aged catalysts present high activity in presence of O 2 and O 2 /NO. The values of the combustion temperature decrease more than 200 deg. C with respect to that observed in the process without catalysis. The activity is associated with the presence of KNO 3 and the role of this salt can be attributed to the contribution of NO 3 - /NO 2 - redox cycle.

Study on the Combustion Process and Emissions of a Turbocharged Diesel Engine with EGR

Directory of Open Access Journals (Sweden)

Mei Deqing

2012-01-01

Full Text Available A high pressure EGR system was adopted to a turbocharged inter-cooled diesel engine, to analyze its combustion and emission characteristics under the condition of different loads and constant speed. Under the same steady operating mode, with the increase of EGR rate, the temperature of compressed gas ascended, the ignition delay was shortened, the pressure and temperature of the burned gas descended, and the combustion process was prolonged. According to the experimental data, it was found that, at the same EGR rate, lower the load of engine was, lower the temperature in cylinder, and higher the increase rate of CO was. However, the increase rate of HC present a falling trend. The decrease rate of the specific emission of NOx linearly varied with EGR rate with a slope of 1.651. The increase rate of smoke opacity behaved a second-order polynomial uprising trend, and the higher the load was, the sharpener the smoke opacity deteriorated, with the increase of EGR rate. From the point of emission view, the engine with EGR system can achieve the lesser exhaust emissions in some operations by adjusting the engine parameters.

Impact of physical properties of mixture of diesel and biodiesel fuels on hydrodynamic characteristics of fuel injection system

Directory of Open Access Journals (Sweden)

Filipović Ivan M.

2014-01-01

Full Text Available One of the alternative fuels, originating from renewable sources, is biodiesel fuel, which is introduced in diesel engines without major construction modifications on the engine. Biodiesel fuel, by its physical and chemical properties, is different from diesel fuel. Therefore, it is expected that by the application of a biodiesel fuel, the characteristic parameters of the injection system will change. These parameters have a direct impact on the process of fuel dispersion into the engine cylinder, and mixing with the air, which results in an impact on the quality of the combustion process. Method of preparation of the air-fuel mixture and the quality of the combustion process directly affect the efficiency of the engine and the level of pollutant emissions in the exhaust gas, which today is the most important criterion for assessing the quality of the engine. The paper presents a detailed analysis of the influence of physical properties of a mixture of diesel and biodiesel fuels on the output characteristics of the fuel injection system. The following parameters are shown: injection pressure, injection rate, the beginning and duration of injection, transformation of potential into kinetic energy of fuel and increase of energy losses in fuel injection system of various mixtures of diesel and biodiesel fuels. For the analysis of the results a self-developed computer program was used to simulate the injection process in the system. Computational results are verified using the experiment, for a few mixtures of diesel and biodiesel fuels. This paper presents the verification results for diesel fuel and biodiesel fuel in particular.

Emission characteristics of multiple stage diesel combustion. Effect of exhaust gas recirculation; Nidan nensho diesel kikan no haishutsubutsu tokusei. EGR no eikyo

Energy Technology Data Exchange (ETDEWEB)

Hashizume, T.; Miyamoto, T.; Akagawa, H.; Tsujimura, K. [New A.C.E. Institute Co. Ltd., Tokyo (Japan)

1998-05-01

For an aim to reduce NOx emission from diesel engines, it has become possible to realize it with smoke emission maintained at low levels by taking the following steps: initial combustion is carried out as lean pre-mixed combustion by adopting early fuel injection; the fuel is injected again after completion of this combustion; and EGR is combined with two-stage combustion which performs diffusion combustion under high temperature atmosphere. When a large quantity of EGR is used, cylinder temperature drops to have ignition timing delayed in the first stage, serving for improving fuel consumption. The problem of increase in smoke generation is solved by optimizing the injection timing at the second stage to suppress smoke generation increase, resulting in realization of lower NOx emission. By completing the second-stage fuel injection before ignition of the first-stage injection, it was possible to realize further lower NOx emission. Smoke increase due to higher EGR ratio was suppressed by pre-mixing both fuels injected in the first and second stages, although this is a high load operation. In addition, oxygen concentration and cylinder temperature were reduced, the gas pre-mixture was homogenized, and combustion velocity was suppressed by delaying the angle of ignition timing. This made low smoke combustion at {lambda} = 1 possible even in compressed ignition combustion. 8 refs., 12 figs., 1 tab.

Diesel engine exhaust particulate filter with intake throttling incineration control

Energy Technology Data Exchange (ETDEWEB)

Ludecke, O.; Rosebrock, T.

1980-07-08

A description is given of a diesel engine exhaust filter and particulate incineration system in combination with a diesel engine having a normally unthrottled air induction system for admitting combustion air to the engine and an exhaust system for carrying off spent combustion products exhausted from the engine, said filter and incineration system comprising: a combustion resistant filter disposed in the exhaust system and operative to collect and retain portions of the largely carbonaceous particulate matter contained in the engine exhaust products, said fiber being capable of withstanding without substantial damage internal temperatures sufficient to burn the collected particulate matter, a throttle in the indication system and operable to restrict air flow into the engine to reduce the admittance of excess combustion air and thereby increase engine exhaust gas temperature, and means to actuate said throttle periodically during engine operation to an air flow restricting burn mode capable of raising the particulates in said filter to their combustion temperature under certain engine operating conditions and to maintain said throttle mode for an interval adequate to burn retained particulates in the filter.

Experimental validation of a combustion kinetics based multi-zone model for natural gas-diesel RCCI engines

NARCIS (Netherlands)

Mikulski, M.; Bekdemir, C.; Willems, F.P.T.

2016-01-01

This paper presents the validation results of TNO's combustion model designed to support RCCI control development. In-depth validation was performed on a multi-cylinder heavy-duty engine operating in RCCI mode on natural gas and diesel fuel. It was shown that the adopted approach is able to

Real-time modelling of the diesel engine combustion process; Echtzeitfaehige Modellierung des dieselmotorischen Verbrennungsprozesses

Energy Technology Data Exchange (ETDEWEB)

Merz, B.

2008-07-01

The publication investigates single-zone models of diesel engine combustion which are capable, in addition to pre-injection and main injection, to represent post-injection processes on a physical basis. These must function in real time as they are used in ''hardware-in-the-loop'' test stands. Methods to adapt the models to other engine types are explained. Validation is made across the whole characteristic field on the basis of measured data provided by two serial engines. For assessing pollutant production, models are integrated that are capable of calculating NOx and soot formation. These, too, are calculated in real time using appropriate hardware systems. A runtime analysis compares the computing times of the models. (orig.)

Chemical characterization and toxicity assessment of fine particulate matters emitted from the combustion of petrol and diesel fuels.

Science.gov (United States)

Wu, Di; Zhang, Fei; Lou, Wenhao; Li, Dan; Chen, Jianmin

2017-12-15

Fuel consumption is one of the major contributors to air pollution worldwide. Plenty of studies have demonstrated that the diesel and petrol exhaust fine particulate matters (FPMs) are associated with increases of various diseases. However, the influences of different fuel types and their chemical components on toxicity have been less investigated. In this study, four kinds of fuels that widely used in China were burned in a laboratory simulation, and the FPMs were collected and analyzed. Transmission electron microscopy showed that black carbon was mainly soot with a dendritic morphology. For light diesel oil, marine heavy diesel oil, 93 octane petrol and 97 octane petrol diesel oil, the emission factors of FPMs were 3.05±0.29, 3.21±0.54, 2.36±0.33, and 2.28±0.25g/kg fuel, respectively. And the emission factors for the "16 US EPA" PAHs of FPM were 0.45±0.20, 0.80±0.22, 1.00±0.20, and 1.05±0.19mg/g FPMs, respectively. Fe is the most abundant metal in these FPMs, and the emission factors of FPMs were 2.58±1.70, 4.45±0.11, 8.18±0.58, and 9.24±0.17mg/g FPMs, respectively. We ranked the cytotoxicity of the FPMs emission from fuels combustion: marine heavy diesel oil>97 octane petrol>93 octane petrol>light diesel oil, and the genotoxicity of FPMs emission from fuels combustion: marine heavy diesel oil>light diesel oil>93 octane petrol>97 octane petrol. Significant correlations were found between PAH concentrations and reactive oxygen species (ROS) generation. Our results demonstrated that fuels exhaust FPMs have strong association with ROS activity, cytotoxicity and genotoxicity. These results indicated that fuels exhaust FPMs pose a potentially serious health, and emphasized the importance of assessing the health risks posed by the particulate pollutants in vehicle exhausts. Copyright © 2017. Published by Elsevier B.V.

New perspectives for advanced automobile diesel engines

Science.gov (United States)

Tozzi, L.; Sekar, R.; Kamo, R.; Wood, J. C.

1983-01-01

Computer simulation results are presented for advanced automobile diesel engine performance. Four critical factors for performance enhancement were identified: (1) part load preheating and exhaust gas energy recovery, (2) fast heat release combustion process, (3) reduction in friction, and (4) air handling system efficiency. Four different technology levels were considered in the analysis. Simulation results are compared in terms of brake specific fuel consumption and vehicle fuel economy in km/liter (miles per gallon). Major critical performance sensitivity areas are: (1) combustion process, (2) expander and compressor efficiency, and (3) part load preheating and compound system. When compared to the state of the art direct injection, cooled, automobile diesel engine, the advanced adiabatic compound engine concept showed the unique potential of doubling the fuel economy. Other important performance criteria such as acceleration, emissions, reliability, durability and multifuel capability are comparable to or better than current passenger car diesel engines.

Study on a small diesel engine with direct injection impinging distribution spray combustion system. Optimum of injection system and combustion chamber; Shototsu kakusan hoshiki kogata diesel kikan ni kansuru kenkyu. Funshakei to nenshoshitsu no saitekika

Energy Technology Data Exchange (ETDEWEB)

Fujita, K; Kato, S; Saito, T [Kanazawa Institute of Technology, Ishikawa (Japan); Tanabe, H [Gunma University, Gunma (Japan)

1997-10-01

This study is concerned with a small bore (93mm) diesel engine using impinged fuel spray, named OSKA system. The higher rate of injection show lower smoke emission with higher NOx Emission. The exhaust emission and performance were investigated under different compression ratio with higher rate of injection. The experimental results show that this OSKA system is capable for reducing the smoke emission without the deterioration of NOx emission and fuel consumption compared with the conventional DI diesel engine. 5 refs., 8 figs., 3 tabs.

Complete modeling for systems of a marine diesel engine

Science.gov (United States)

Nahim, Hassan Moussa; Younes, Rafic; Nohra, Chadi; Ouladsine, Mustapha

2015-03-01

This paper presents a simulator model of a marine diesel engine based on physical, semi-physical, mathematical and thermodynamic equations, which allows fast predictive simulations. The whole engine system is divided into several functional blocks: cooling, lubrication, air, injection, combustion and emissions. The sub-models and dynamic characteristics of individual blocks are established according to engine working principles equations and experimental data collected from a marine diesel engine test bench for SIMB Company under the reference 6M26SRP1. The overall engine system dynamics is expressed as a set of simultaneous algebraic and differential equations using sub-blocks and S-Functions of Matlab/Simulink. The simulation of this model, implemented on Matlab/Simulink has been validated and can be used to obtain engine performance, pressure, temperature, efficiency, heat release, crank angle, fuel rate, emissions at different sub-blocks. The simulator will be used, in future work, to study the engine performance in faulty conditions, and can be used to assist marine engineers in fault diagnosis and estimation (FDI) as well as designers to predict the behavior of the cooling system, lubrication system, injection system, combustion, emissions, in order to optimize the dimensions of different components. This program is a platform for fault simulator, to investigate the impact on sub-blocks engine's output of changing values for faults parameters such as: faulty fuel injector, leaky cylinder, worn fuel pump, broken piston rings, a dirty turbocharger, dirty air filter, dirty air cooler, air leakage, water leakage, oil leakage and contamination, fouling of heat exchanger, pumps wear, failure of injectors (and many others).

Diesel engine management systems and components

CERN Document Server

2014-01-01

This reference book provides a comprehensive insight into todays diesel injection systems and electronic control. It focusses on minimizing emissions and exhaust-gas treatment. Innovations by Bosch in the field of diesel-injection technology have made a significant contribution to the diesel boom. Calls for lower fuel consumption, reduced exhaust-gas emissions and quiet engines are making greater demands on the engine and fuel-injection systems. Contents History of the diesel engine.- Areas of use for diesel engines.- Basic principles of the diesel engine.- Fuels: Diesel fuel.- Fuels: Alternative fuels.- Cylinder-charge control systems.- Basic principles of diesel fuel-injection.- Overview of diesel fuel-injection systems.- Fuel supply to the low pressure stage.- Overview of discrete cylinder systems.- Unit injector system.- Unit pump system.- Overview of common-rail systems.- High pressure components of the common-rail system.- Injection nozzles.- Nozzle holders.- High pressure lines.- Start assist systems.-...

Influencia del porcentaje de mezcla del aceite de higuerilla en la obtención de combustible alternativo para motores diesel

Directory of Open Access Journals (Sweden)

Arnoldo Emilio Delgado

2011-01-01

Full Text Available En el presente artículo se describe el uso del aceite de higuerilla como combustible alternativo en motores diesel. Para este fi n, se obtiene biodiesel a partir de aceite de higuerilla mediante el proceso de transesterifi cación. Se prueban tres mezclas de biodiesel (B5%, B10% y B20% en un motor diesel, para el cual se midieron los siguientes parámetros: la potencia, el consumo de combustible, la temperatura del motor, y los gases de combustión;las mezclas fueron caracterizadas mediante la densidad, viscosidad, índice de refracción y calor de combustión. Se determinó que el uso del aceite de higuerilla en la mezcla genera un aumento en la viscosidad y el consumo de combustible, además también infl uye en la reducción del poder calorífico, potencia del motor, los gases de combustión como el CO y CO2, los óxidos de azufre, los hidrocarburos, la opacidad en los humos del escape del motor y ocasiona un equilibrio en el rendimiento observado en el motor diesel, manifi esto en las temperaturas del motor.

Development of High Efficiency and Low Emission Low Temperature Combustion Diesel Engine with Direct EGR Injection

Science.gov (United States)

Ho, R. J.; Kumaran, P.; Yusoff, M. Z.

2016-03-01

Focus on energy and environmental sustainability policy has put automotive research & development directed to developing high efficiency and low pollutant power train. Diffused flame controlled diesel combustion has reach its limitation and has driven R&D to explore other modes of combustions. Known effective mode of combustion to reduce emission are Low temperature combustion (LTC) and homogeneous charge combustion ignition by suppressing Nitrogen Oxide(NOx) and Particulate Matter (PM) formation. The key control to meet this requirement are chemical composition and distribution of fuel and gas during a combustion process. Most research to accomplish this goal is done by manipulating injected mass flow rate and varying indirect EGR through intake manifold. This research paper shows viable alternative direct combustion control via co-axial direct EGR injection with fuel injection process. A simulation study with OpenFOAM is conducted by varying EGR injection velocity and direct EGR injector diameter performed with under two conditions with non-combustion and combustion. n-heptane (C7H16) is used as surrogate fuel together with 57 species 290 semi-detailed chemical kinetic model developed by Chalmers University is used for combustion simulation. Simulation result indicates viability of co-axial EGR injection as a method for low temperature combustion control.

Combustion characteristics of the mustard methyl esters

International Nuclear Information System (INIS)

Bannikov, M.G.; Vasilev, I.P.

2011-01-01

Mustard Methyl Esters (further bio diesel) 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 bio diesel 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 bio diesel and partially to decreased fuel conversion efficiency. Analysis of combustion characteristics revealed earlier start of injection and shorter ignition delay period of bio diesel. 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 bio diesel. Conclusion was made on applicability of mustard oil as a source for commercial production of bio diesel in Pakistan. Potentialities of on improving combustion and emissions characteristics of diesel engine by reformulating bio diesel were discussed. (author)

Desempenho de misturas pré-aquecidas de óleo de soja cru e diesel como combustível para motores agrícolas Performance of preheated crude soybean oil-diesel blends as fuel in agricultural engines

Directory of Open Access Journals (Sweden)

José Fernando Schlosser

2007-10-01

Full Text Available O óleo de soja é um dos óleos vegetais que têm potencial de uso como combustível para motores diesel, pois é renovável, seguro e de fácil utilização. Em temperatura ambiente, o óleo cru apresenta uma viscosidade cerca de dez vezes maior que a do óleo diesel. Para reduzir a viscosidade do óleo de soja a níveis aceitáveis, é necessária uma temperatura de aquecimento em torno de aproximadamente 60°C ou misturá-lo com óleo diesel. O objetivo deste estudo foi avaliar o desempenho do óleo de soja cru e suas misturas com óleo diesel, pré-aquecidas antes da bomba injetora entre 57°C e 68°C, como combustível para motores diesel. O desempenho das misturas combustíveis foi avaliado num motor monocilíndrico de injeção indireta e comparado com o obtido pelo óleo diesel. Os ensaios de curta duração foram conduzidos entre 1.800 e 2.800rpm, sob condição de plena carga em dinamômetro hidráulico. Ensaios realizados a 68°C apresentaram sempre os melhores valores para torque, potência e consumo específico de combustível do que a 57°C. Uma mistura composta por 70% de óleo de soja e 30% de óleo diesel, aquecida a 68°C, apresentou os melhores resultados.Crude soybean oil is one of the vegetable oils that have potential for use as fuel for diesel engines. Soybean oil is renewable, and is safe and easy to handle. At room temperature crude oil has a viscosity about ten times higher than that of diesel oil. To lower soybean oil's viscosity to the acceptable levels a heating temperature at least 60°C is needed or blending with diesel fuel. The objective of this study was evaluating the soybean oil and blends performance as a fuel for diesel engines. On both crude soybean oil and soybean oil blends were used pre-heating temperature levels on the range between 57°C and 68°C, before fuel pump. The performance of the fuel blends were evaluated in a single cylinder indirect injection diesel engine and compared with the performance

Combustion Stratification for Naphtha from CI Combustion to PPC

KAUST Repository

Vallinayagam, R.; Vedharaj, S.; An, Yanzhao; Dawood, Alaaeldin; Izadi Najafabadi, Mohammad; Somers, Bart; Johansson, Bengt

2017-01-01

This study demonstrates the combustion stratification from conventional compression ignition (CI) combustion to partially premixed combustion (PPC). Experiments are performed in an optical CI engine at a speed of 1200 rpm for diesel and naphtha (RON

Improvement studies on emission and combustion characteristics of DICI engine fuelled with colloidal emulsion of diesel distillate of plastic oil, TiO2 nanoparticles and water.

Science.gov (United States)

Karisathan Sundararajan, Narayanan; Ammal, Anand Ramachandran Bhagavathi

2018-04-01

Experimentation was conducted on a single cylinder CI engine using processed colloidal emulsions of TiO 2 nanoparticle-water-diesel distillate of crude plastic diesel oil as test fuel. The test fuel was prepared with plastic diesel oil as the principal constituent by a novel blending technique with an aim to improve the working characteristics. The results obtained by the test fuel from the experiments were compared with that of commercial petro-diesel (CPD) fuel for same engine operating parameters. Plastic oil produced from high density polyethylene plastic waste by pyrolysis was subjected to fractional distillation for separating plastic diesel oil (PDO) that contains diesel range hydrocarbons. The blending process showed a little improvement in the field of fuel oil-water-nanometal oxide colloidal emulsion preparation due to the influence of surfactant in electrostatic stabilization, dielectric potential, and pH of the colloidal medium on the absolute value of zeta potential, a measure of colloidal stability. The engine tests with nano-emulsions of PDO showed an increase in ignition delay (23.43%), and decrease in EGT (6.05%), BSNO x (7.13%), and BSCO (28.96%) relative to PDO at rated load. Combustion curve profiles, percentage distribution of compounds, and physical and chemical properties of test fuels ascertains these results. The combustion acceleration at diffused combustion phase was evidenced in TiO 2 emulsion fuels under study.

Atomic layer deposition of cerium oxide for potential use in diesel soot combustion

Energy Technology Data Exchange (ETDEWEB)

Ivanova, Tatiana V., E-mail: tatiana.ivanova@lut.fi, E-mail: ivanova.tatyana.v@gmail.com; Toivonen, Jenni; Maydannik, Philipp S.; Kääriäinen, Tommi; Sillanpää, Mika [ASTRaL Team, Laboratory of Green Chemistry, School of Engineering Science, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli (Finland); Homola, Tomáš; Cameron, David C. [R& D Centre for Low-Cost Plasma and Nanotechnology Surface Modification, Masaryk University, Kotlářská 267/2, 611 37 Brno (Czech Republic)

2016-05-15

The particulate soot emission from diesel motors has a severe impact on the environment and people's health. The use of catalytic convertors is one of the ways to minimize the emission and decrease the hazard level. In this paper, the activity of cerium oxide for catalytic combustion of diesel soot was studied. Thin films of cerium dioxide were synthesized by atomic layer deposition using tetrakis(2,2,6,6-tetramethyl-3,5-heptanedionato)cerium [Ce(thd){sub 4}] and ozone as precursors. The characteristics of the films were studied as a function of deposition conditions within the reaction temperature range of 180–350 °C. Thickness, crystallinity, elemental composition, and morphology of the CeO{sub 2} films deposited on Si (100) were characterized by ellipsometry, x-ray diffraction, x-ray photoelectron spectroscopy, atomic force microscopy, and field emission scanning electron microscopy, respectively. The growth rate of CeO{sub 2} was observed to be 0.30 Å/cycle at temperatures up to 250 °C with a slight increase to 0.37 Å/cycle at 300 °C. The effect of CeO{sub 2} films grown on stainless steel foil supports on soot combustion was measured with annealing tests. Based on the analysis of these, in catalytic applications, CeO{sub 2} has been shown to be effective in lowering the soot combustion temperature from 600 °C for the uncoated substrates to 370 °C for the CeO{sub 2} coated ones. It was found that the higher deposition temperatures had a positive effect on the catalyst performance.

Experimental Investigation of the Effect of Biodiesel Blends on a DI Diesel Engine’s Injection and Combustion

Directory of Open Access Journals (Sweden)

Dimitrios N Tziourtzioumis

2017-07-01

Full Text Available Differences in the evolution of combustion in a single cylinder, DI (direct injection diesel engine fuelled by B20 were observed upon processing of the respective indicator diagrams. Aiming to further investigate the effects of biodiesel on the engine injection and combustion process, the injection characteristics of B0, B20, B40, B60, B80 and B100 were measured at low injection pressure and visualized at low and standard injection pressures. The fuel atomization characteristics were investigated in terms of mean droplet velocity, Sauter mean diameter, droplet velocity and diameter distributions by using a spray visualization system and Laser Doppler Velocimetry. The jet break-up characteristics are mainly influenced by the Weber number, which is lower for biodiesel, mainly due to its higher surface tension. Thus, Sauter mean diameter (SMD of sprays with biodiesel blended-fuel is higher. Volume mean diameter (VMD and arithmetic mean diameter (AMD values also increase with blending ratio. Kinematic viscosity and surface tension become higher as the biodiesel blending ratio increases. The SMD, VMD and AMD of diesel and biodiesel blended fuels decreased with an increase in the axial distance from spray tip. Comparison of estimated fuel burning rates for 60,000 droplets’ samples points to a decrease in mean fuel burning rate for B20 and higher blends.

Combustion characteristics, performance and exhaust emissions of a diesel engine fueled with a waste cooking oil biodiesel mixture

International Nuclear Information System (INIS)

Can, Özer

2014-01-01

Highlights: • High quality biodiesel fuels can be produced by using different waste cooking oils. • Biodiesel fuel blends (in 5 and 10% vol) can be used without any negative effects. • Effects of biodiesel addition on the combustion and exhaust emissions were investigated. - Abstract: In this study, a mixture of biodiesel fuels produced from two different kinds of waste cooking oils was blended in 5% and 10% with No. 2 diesel fuel. The biodiesel/No. 2 diesel fuel blends were tested in a single-cylinder, direct injection, four-stroke, natural aspirated diesel engine under four different engine loads (BMEP 0.48–0.36–0.24–0.12 MPa) and 2200 rpm engine speed. Despite of the earlier start of injection, the detailed combustion and engine performance results showed that the ignition delay with the biodiesel addition was decreased for the all engine loads with the earlier combustion timings due to higher cetane number of biodiesel fuel. Meanwhile the maximum heat release rate and the in-cylinder pressure rise rate were slightly decreased and the combustion duration was generally increased with the biodiesel addition. However, significant changings were not observed on the maximum in-cylinder pressures. In addition, it was observed that the indicated mean effective pressure values were slightly varied depending on the start of combustion timing and the center of heat release location. It was found that 5% and 10% biodiesel fuel addition resulted in slightly increment on break specific fuel consumption (up to 4%) and reduction on break thermal efficiency (up to 2.8%). The biodiesel additions also increased NO x emissions up to 8.7% and decreased smoke and total hydrocarbon emissions for the all engine loads. Although there were no significant changes on CO emissions at the low and medium engine loads, some reductions were observed at the full engine load. Also, CO 2 emissions were slightly increased for the all engine loads

Numerical studies of spray combustion processes of palm oil biodiesel and diesel fuels using reduced chemical kinetic mechanisms

KAUST Repository

Kuti, Olawole; Sarathy, Mani; Nishida, Keiya; Roberts, William L.

2014-01-01

Spray combustion processes of palm oil biodiesel (PO) and conventional diesel fuels were simulated using the CONVERGE CFD code. Thermochemical and reaction kinetic data (115 species and 460 reactions) by Luo et al. (2012) and Lu et al. (2009) (68

Diesel and gas engines: evolution facing new regulations; Moteurs diesel et gaz: evolution face aux nouvelles reglementations

Energy Technology Data Exchange (ETDEWEB)

Daverat, Ph. [Bergetat Monnoyeur (France)

1997-12-31

This paper analyzes the influence of new pollution regulations on the new design of diesel and gas engines with the example of Caterpillar`s experience, one of the leaders of diesel and gas engines manufacturers worldwide. The technical problems to solve are introduced first (reduction of NO{sub x}, SO{sub 2}, CO, unburned compounds and dusts), and then the evolution of engines and of exhaust gas treatment systems are described (fuel injection systems, combustion and ignition control, sensors, catalytic conversion and filtering systems). (J.S.)

Reducing Diesel Engine Emission Using Reactivity Controlled Approach

Directory of Open Access Journals (Sweden)

Osama Hasib Ghazal

2018-01-01

Full Text Available Several automobile manufacturers are interested in investigating of dual fuel internal combustion engines, due to high efficiencand low emissions. Many alternative fuels have been used in dual fuel mode for IC engine, such as methane, hydrogen, and natural gas. In the present study, a reactivity controlled compression ignition (RCCI engine using gasoline/diesel (G/D dual fuel has been investigated. The effectof mixing gasoline with diesel fuel on combustion characteristic, engine performance and emissions has been studied. The gasoline was injected in the engine intake port, to produce a homogeneous mixture with air. The diesel fuel was injected directly to the combustion chamber during compression stroke to initiate the combustion process. A direct injection compression ignition engine has been built and simulated using ANSYS Forte professional code. The gasoline amount in the simulation varied from (50%-80% by volume. The diesel fuel was injected to the cylinder in two stages. The model has been validated and calibrated for neat diesel fuel using available data from the literature. The results show that the heat release rate and the cylinder pressure increased when the amount of added gasoline is between 50%-60% volume of the total injected fuels, compared to the neat diesel fuel. Further addition of gasoline will have a contrary effect. In addition, the combustion duration is extended drastically when the gasoline ratio is higher than 60% which results in an incomplete combustion. The NO emission decreased drastically as the gasoline ratio increased. Moreover, addition of gasoline to the mixture increased the engine power, thermal efficienc and combustion efficienc compared to neat diesel fuel.

Investigation of the effects of steam injection on performance and NO emissions of a diesel engine running with ethanol–diesel blend

International Nuclear Information System (INIS)

Gonca, Guven

2014-01-01

Highlights: • A combustion simulation is conducted by using two-zone combustion model. • Effect of steam injection into engine fueled ethanol–diesel blend are investigated. • It is shown that this method improves performance and diminish NO emissions. - Abstract: The use of ethanol–diesel blends in diesel engines without any modifications negatively affects the engine performance and NOx emissions. However, steam injection method decreases NOx emissions and improves the engine performance. In this study, steam injection method is applied into a single cylinder, four-stroke, direct injection, naturally aspirated diesel engine fueled with ethanol–diesel blend in order improve the performance and NOx emissions by using two-zone combustion model for 15% ethanol addition and 20% steam ratios at full load condition. The results obtained are compared with conventional diesel engine (D), steam injected diesel engine (D + S20), diesel engine fueled with ethanol–diesel blend (E15) and steam injected diesel engine fueled with ethanol–diesel blend (E15 + S20) in terms of performance and NO emissions. The results showed that as NO emissions considerably decrease the performance significantly increases with steam injection method

Effects of port fuel injection (PFI) of n-butanol and EGR on combustion and emissions of a direct injection diesel engine

International Nuclear Information System (INIS)

Chen, Zheng; Liu, Jingping; Wu, Zhenkuo; Lee, Chiafon

2013-01-01

Highlights: • A DI diesel engine with PFI of n-butanol in combination with EGR is investigated. • Butanol concentration and EGR have a coupled impact on combustion process. • A combination of butanol PFI and EGR can break through tradeoff between NOx and soot. • DI diesel with butanol PFI has lower ITE than DI of diesel–butanol blends. - Abstract: An experimental investigation was conducted on a direct injection (DI) diesel engine with exhaust gas recirculation (EGR), coupled with port fuel injection (PFI) of n-butanol. Effects of butanol concentration and EGR rate on combustion, efficiency, and emissions of the tested engine were evaluated, and also compared to a DI mode of diesel–butanol blended fuel. The results show butanol concentration and EGR rate have a coupled impact on combustion process. Under low EGR rate condition, both the peak cylinder pressure and the peak heat release rate increase with increased butanol concentration, but no visible influence was found on the ignition delay. Under high EGR rate condition, however, the peak cylinder pressure and the peak heat release rate both decrease with increased butanol concentration, accompanied by longer ignition delay and longer combustion duration. As regard to the regulated emissions, HC and CO emissions increase with increased butanol concentration, causing higher indicated specific fuel consumption (ISFC) and lower indicated thermal efficiency (ITE). It is also noted that butanol PFI in combination with EGR can change the trade-off relationship between NOx and soot, and simultaneously reduce both into a very low level. Compared with the DI mode of diesel–butanol blended fuel, however, the DI diesel engine with butanol PFI has higher HC and CO emissions and lower ITE. Therefore, future research should be focused on overcoming the identified shortcomings by an improved injection strategy of butanol PFI

El biodiesel de aceite de higuerilla como combustible alternativo para motores diesel

OpenAIRE

ALIRIO BENAVIDES; PEDRO BENJUMEA; VESELINA PASHOVA

2007-01-01

En este artículo se presenta un estudio experimental sobre la producción y utilización del biodiesel de aceite de higuerilla. El máximo rendimiento de metilésteres en la reacción de transesterificación del aceite de higuerilla usado se obtiene bajo las siguientes condiciones: temperatura ambiente, una relación molar metanol/aceite de 9 y una concentración de catalizador de 0.8%. El biodiesel de aceite de higuerilla puede ser mezclado con el combustible diesel convencional derivado del petróle...

EL BIODIESEL DE ACEITE DE HIGUERILLA COMO COMBUSTIBLE ALTERNATIVO PARA MOTORES DIESEL

OpenAIRE

BENAVIDES, ALIRIO; BENJUMEA, PEDRO; PASHOVA, VESELINA

2007-01-01

En este artículo se presenta un estudio experimental sobre la producción y utilización del biodiesel de aceite de higuerilla. El máximo rendimiento de metilésteres en la reacción de transesterificación del aceite de higuerilla usado se obtiene bajo las siguientes condiciones: temperatura ambiente, una relación molar metanol/aceite de 9 y una concentración de catalizador de 0.8%. El biodiesel de aceite de higuerilla puede ser mezclado con el combustible diesel convencional derivado del petróle...

Enhancing instruction in Fuels and Combustion Laboratory via a developed computer-assisted program for establishing efficient coal-diesel oil mixture (CDOM) fuel proportions

Energy Technology Data Exchange (ETDEWEB)

Maglaya, A.B. [La Salle University, Manila (Philippines). Dept. of Mechanical Engineering

2004-07-01

This paper discusses the relevance of digital computation in Fuels and Combustion Laboratory experiments used by the senior students of the Department of Mechanical Engineering, De La Salle University-Manila, Philippines. One of the students' experiments involved the determination of the most efficient CDOM fuel proportion as alternative fuel to diesel oil for steam generators and other industrial applications. Theoretical calculations show that it requires tedious and repetitive computations. A computer-assisted program was developed to lessen the time-consuming activities. The formulation of algorithms were based on the system of equations of the heat interaction between the CDOM fuel, combustion air and products of combustion and by applying the principles of mass and energy equations (or the First Law of Thermodynamics) for reacting systems were utilized. The developed computer-assisted program output verified alternative fuel selected through actual experimentation.

Image processing analysis of combustion for D. I. diesel engine with high pressure fuel injection. ; Effects of air swirl and injection pressure. Nensho shashin no gazo shori ni yoru koatsu funsha diesel kikan no nensho kaiseki. ; Swirl oyobi funsha atsuryoku no eikyo

Energy Technology Data Exchange (ETDEWEB)

Yamaguchi, I. (Japan Automobile Research Institute, Inc., Tsukuba (Japan)); Tsujimura, K.

1994-02-25

This paper reports an image processing analysis of combustion for a high-pressure direct injection diesel engine on the effects of air swirl and injection pressure upon combustion in the diesel engine. The paper summarizes a method to derive gas flow and turbulence strengths, and turbulent flow mixing velocity. The method derives these parameters by detecting movement of brightness unevenness on two flame photographs through utilizing the mutual correlative coefficients of image concentrations. Five types of combustion systems having different injection pressures, injection devices, and swirl ratios were used for the experiment. The result may be summarized as follows: variation in the average value of the turbulent flow mixing velocities due to difference in the swirl ratio is small in the initial phase of diffusion combustion; the difference is smaller in the case of high swirl ratio than in the case of low swirl ratio after the latter stage of the injection; the average value is larger with the higher the injection pressure during the initial stage of the combustion; after termination of the injection, the value is larger in the low pressure injection; and these trends agree with the trend in the time-based change in heat generation rates measured simultaneously. 6 refs., 14 figs., 2 tabs.

Feasibility study of utilizing jatropha curcas oil as bio-diesel in an oil firing burner system

Science.gov (United States)

Shaiful, A. I. M.; Jaafar, M. N. Mohd; Sahar, A. M.

2017-09-01

Jatropha oil derived from the Jatropha Curcas Linnaeus is one of the high potential plants to be use as bio-diesel. The purpose of this research is to carry out a feasibility study of using jatropha oil as bio-diesel on oil firing burner system. Like other bio-diesels, jatropha oil can also be used in any combustion engine and the performance and emissions such as NOx, SO2, CO and CO2 as well as unburned hydocarbon (UHC) from the engine will vary depending on the bio-diesel blends. The properties of Conventional Diesel Fuel (CDF) obtained will be used as baseline and the jatropha oil properties will be compared as well as other bio-diesels. From several researches, the properties of jatropha oil was found to be quite similar with other bio-diesel such as palm oil, neem, keranja and pongamia bio-diesel and complying with the ASTM standard for bio-diesel. Still, there are factors and issues concerning the use of jatropha oil such as technology, economy, legislation and resource. Plus, there several challenges to the growth of bio-diesel industry development since the world right now do not totally depend on the bio-diesel.

Bio diesel- the Clean, Green Fuel for Diesel Engines

International Nuclear Information System (INIS)

Elkareish, S.M.M.

2004-01-01

Natural, renewable resources such as vegetable oils, animal fats and recycled restaurant greases can be chemically transformed into clean burning bio diesel fuels (1). Just like petroleum diesel, bio diesel operates in combustion-ignition engines. Blends of up to 20% bio diesel (mixed with petroleum diesel fuels) can be used in nearly all diesel equipment and are compatible with most storage and distribution equipment. Using bio diesel in a conventional diesel engine substantially reduces emissions of unburned hydrocarbons, carbon monoxide, sulphates, polycyclic aromatic hydrocarbons, nitrated polycyclic aromatic hydrocarbons, and particulate matter. The use of bio diesel has grown dramatically during the last few years. Egypt has a promising experiment in promoting forestation by cultivation of Jatropha plant especially in luxor and many other sites of the country. The first production of the Egyptian Jatropha seeds oil is now under evaluation to produce a cost-competitive bio diesel fuel

Radium in diesel oil

International Nuclear Information System (INIS)

Kulich, J.

1977-05-01

In order to determine the addition of radon and radium to the air in mines, originatiny from the combustion of petroleum, measurements of the content of radium in diesel oil have been performed. Knowing the radium content theradon content can easily be calculated. The procedures used for the chemical analysis of radium is desribed. The ash remaining after combustion of the diesel oil is soluted in water and radium is precipiated as sulphate. The radium is detected by a ZnS (Ag) detector. The diesel oils from different petroleum companies contained between o.019-0.5pCi radium - 226. The conclution is that the consumption of diesel oils in motors used in mines does not contribute to the radium - 226 content at the air move than permissible according to norms.(K.K.)

Combustion performance and emission analysis of diesel engine fuelled with water-in-diesel emulsion fuel made from low-grade diesel fuel

International Nuclear Information System (INIS)

Ithnin, Ahmad Muhsin; Ahmad, Mohamad Azrin; Bakar, Muhammad Aiman Abu; Rajoo, Srithar; Yahya, Wira Jazair

2015-01-01

Highlights: • Effect of using emulsified fuel made from low-grade fuel in engine are investigated. • Specific fuel consumption of the engine is reduced overall for all types of W/D. • Comparable maximum in-cylinder pressure and pressure rise rate compared to D2. • NOx and PM are found to be reduced for all types of W/D. • CO and CO 2 emissions increase compared to D2 at low load and high load. - Abstract: In the present research, an experiment is designed and conducted to investigate the effect of W/D originating from low-grade diesel fuel (D2) on the combustion performance and emission characteristics of a direct injection diesel engine under varying engine loads (25–100%) and constant engine speed (3000 rpm). Four types of W/D are tested, which consist of different water percentages (5%, 10%, 15% and 20%), with constant 2% of surfactant and labelled as E5, E10, E15 and E20, respectively. The specific fuel consumption (SFC) of the engine when using each type of W/D is found to be reduced overall. This is observed when the total amount of diesel fuel in the emulsion is compared with that of neat D2. E20 shows a comparable maximum in-cylinder pressure and pressure rise rate (PRR) compared to D2 in all load conditions. In addition, it produces the highest maximum rate of heat release (MHRR) in almost every load compared to D2 and other W/Ds. NOx and PM are found to be reduced for all types of W/D. The carbon monoxide (CO) and carbon dioxide (CO 2 ) emissions increase compared to D2 at low load and high load, respectively. Overall, it is observed that the formation of W/D from low-grade diesel is an appropriate alternative fuel method that can bring about greener exhaust emissions and fuel savings without deteriorating engine performance

Application of an EGR system in a direct injection diesel engine to reduce NOx emissions

Science.gov (United States)

De Serio, D.; De Oliveira, A.; Sodré, J. R.

2016-09-01

This work presents the application of an exhaust gas recirculation (EGR) system in a direct injection diesel engine operating with diesel oil containing 7% biodiesel (B7). EGR rates of up to 10% were applied with the primary aim to reduce oxides of nitrogen (NOx) emissions. The experiments were conducted in a 44 kW diesel power generator to evaluate engine performance and emissions for different load settings. The use of EGR caused a peak pressure reduction during the combustion process and a decrease in thermal efficiency, mainly at high engine loads. A reduction of NOx emissions of up to 26% was achieved, though penalizing carbon monoxide (CO) and total hydrocarbons (THC) emissions.

From fuel to wheel: how modern fuels behave in combustion engines

Energy Technology Data Exchange (ETDEWEB)

Pischinger, S.; Muether, M.; Fricke, F. [RWTH Aachen (Germany). Inst. for Combustion Engines; Kolbeck, A. [FEV Motorentechnik GmbH und Co KG, Aachen (Germany)

2007-07-01

Fuel consumption/CO{sub 2}-emission reduction for spark-ignited (SI) gasoline engines and pollutant emission reduction for compression-ignited (CI) Diesel engines remain the major challenges for future combustion engine research and development. Currently a variety of technological developments is followed. The fuel has significant influence on the fuel injection and mixing, the self-ignition behaviour and the subsequent combustion process, and hence has considerable impact on the engine conversion efficiency and the emission characteristics. Therefore, a very promising approach to improve the engine efficiency and to lower the pollutant emission is to optimize the fuel composition. Several diesel-like fuels with varying aromatic concentrations (mono-, di-, tri- and total aromatics) and oxygenating components have already shown potential for soot reduction in diesel engines, which is of interest when looking at future biofuel components, which will most likely have particular higher oxygen content. 2nd generation biofuels, e.g. ethanol for SI engines and Fischer-Tropsch diesel for CI engines, have already demonstrated their positive influence on the engine performance, when the combustion system is specifically adapted. The full potential for future high efficient and low emission combustion systems can only be exploited by a simultaneous optimisation of the fuel and the internal combustion engine. (orig.)

An experimental study of the combusition and emission performances of 2,5-dimethylfuran diesel blends on a diesel engine

Directory of Open Access Journals (Sweden)

Xiao Helin

2017-01-01

Full Text Available Experiments were carried out in a direct injection compression ignition engine fueled with diesel-dimethylfuran blends. The combustion and emission performances of diesel-dimethylfuran blends were investigated under various loads ranging from 0.13 to 1.13 MPa brake mean effective pressure, and a constant speed of 1800 rpm. Results indicate that diesel-dimethylfuran blends have different combustion performance and produce longer ignition delay and shorter combustion duration compared with pure diesel. Moreover, a slight increase of brake specific fuel consumption and brake thermal efficiency occurs when a Diesel engine operates with blended fuels, rather than diesel fuel. Diesel-dimethylfuran blends could lead to higher NOx emissions at medium and high engine loads. However, there is a significant reduction in soot emission when engines are fueled with diesel-dimethylfuran blends. Soot emissions under each operating conditions are similar and close to zero except for D40 at 0.13 MPa brake mean effective pressure. The total number and mean geometric diameter of emitted particles from diesel-dimethylfuran blends are lower than pure diesel. The tested fuels exhibit no significant difference in either CO or HC emissions at medium and high engine loads. Nevertheless, diesel fuel produces the lowest CO emission and higher HC emission at low loads of 0.13 to 0.38 MPa brake mean effective pressure.

Combustion of simulated biogas in a dual-fuel diesel engine

Energy Technology Data Exchange (ETDEWEB)

Henham, A.; Makkar, M.K. [University of Surrey, Guildford (United Kingdom). School of Mechanical and Materials Engineering

1998-12-31

Technology related to biogas has been steadily developed over the last 50 years from small individually designed units to larger production plants. The development, however, has largely taken place on the side of biogas production and anaerobic waste treatment. Utilization of the gas produced by these methods has only recently been the subject of more scientific evaluation. The transformation of energy through biogas into the thermodynamically higher valued mechanical energy successfully and economically is now the most important research area in this field. Of the engine work already published, most concerns spark-ignited engines. The authors` research work concerns the use of biogas in dual-fuel diesel engines. It examines engine performance using simulated biogas of varying quality representing the range of methane:carbon dioxide composition which may be encountered in gas from different sources. The total programme includes the effects of biogas quality and of the proportion of energy from pilot fuel injection over a range of speeds and loads, investigations into the performance parameters over a range of compositions of gaseous mixture. A two-cylinder, indirect-injection diesel engine of stationary type is being used as the first experimental test bed in this work and the variation of quality is provided by mixing natural gas and carbon dioxide. A data acquisition system for an in-cylinder pressure and crank angle is being used successfully and some emissions measurements are also available, particularly for CO and O{sub 2}. The nature of combustion process in the dual-fuel engine is examined through pressure-crank angle data and studies of characteristics affecting engine efficiency. (author)

Influence of the kind of fuel oil on the deposit composition in the diesel engine combustion chamber

Energy Technology Data Exchange (ETDEWEB)

Tarkowski, P.; Sarzynski, J.; Budzynski, P.; Paluch, R.; Wiertel, M. [Technical University of Lublin, Lublin (Poland)

2001-08-10

The authors studied deposits from combustion chambers of high-pressure engines supplied with standard fuel (SO) and ecological fuel of City-Diesel type. Chemical analysis, X-ray diffractograms, Moessbauer absorption and additionally Raman wavenumber measurements were made. The wearing of some engine elements was examined by the profilometric method. By using ecological fuel, the deposits were shown to contain four to give times less iron compounds than standard fuel supply. This accounts for a smaller attrition of the combustion chamber elements, and thus longer durability of the engine. 7 refs., 4 figs., 5 tabs.

Diesel fuel filtration system

International Nuclear Information System (INIS)

Schneider, D.

1996-01-01

The American nuclear utility industry is subject to tight regulations on the quality of diesel fuel that is stored at nuclear generating stations. This fuel is required to supply safety-related emergency diesel generators--the backup power systems associated with the safe shutdown of reactors. One important parameter being regulated is the level of particulate contamination in the diesel fuel. Carbon particulate is a natural byproduct of aging diesel fuel. Carbon particulate precipitates from the fuel's hydrocarbons, then remains suspended or settles to the bottom of fuel oil storage tanks. If the carbon particulate is not removed, unacceptable levels of particulate contamination will eventually occur. The oil must be discarded or filtered. Having an outside contractor come to the plant to filter the diesel fuel can be costly and time consuming. Time is an even more critical factor if a nuclear plant is in a Limiting Condition of Operation (LCO) situation. A most effective way to reduce both cost and risk is for a utility to build and install its own diesel fuel filtration system. The cost savings associated with designing, fabricating and operating the system inhouse can be significant, and the value of reducing the risk of reactor shutdown because of uncertified diesel fuel may be even higher. This article describes such a fuel filtering system

Multi-zone modeling of Diesel engine fuel spray development with vegetable oil, bio-diesel or Diesel fuels

International Nuclear Information System (INIS)

Rakopoulos, C.D.; Antonopoulos, K.A.; Rakopoulos, D.C.

2006-01-01

This work presents a model of fuel sprays development in the cylinders of Diesel engines that is two-dimensional, multi-zone, with the issuing jet (from the nozzle) divided into several discrete volumes, called 'zones', formed along the direction of the fuel injection as well as across it. The model follows each zone, with its own time history, as the spray penetrates into the swirling air environment of the combustion chamber before and after wall impingement. After the jet break up time, a group of droplets is generated in each zone, with the model following their motion during heating, evaporation and mixing with the in-cylinder air. The model is applied for the interesting case of using vegetable oils or their derived bio-diesels as fuels, which recently are considered as promising alternatives to petroleum distillates since they are derived from biological sources. Although there are numerous experimental studies that show curtailment of the emitted smoke with possible increase of the emitted NO x against the use of Diesel fuel, there is an apparent scarcity of theoretical models scrutinizing the formation mechanisms of combustion generated emissions when using these biologically derived fuels. Thus, in the present work, a theoretical detailed model of spray formation is developed that is limited to the related investigation of the physical processes by decoupling it from the chemical effects after combustion initiation. The analysis results show how the widely differing physical properties of these fuels, against the normal Diesel fuel, affect greatly the spray formation and consequently the combustion mechanism and the related emissions

Prediction of major pollutants emission in direct injection dual-fuel diesel and natural-gas engines

International Nuclear Information System (INIS)

Pirouzpanah, V.; Kashani, B.O.

2000-01-01

The dual-fuel diesel engine is a conventional diesel engine in which much of the energy released, hence power, comes from the combustion of gaseous fuel such as natural gas. The exhaust emission characteristics of the dual-fuel diesel engine needs further refinements, particularly in terms of reduction of Unburnt Hydrocarbons and Carbon Monoxide (CO) emission, because the concentration of these pollutants are higher than that of the baseline diesel engine. Furthermore, the combustion process in a typical dual-fuel diesel engine tends to be complex, showing combination of the problems encountered both in diesel and spark ignition engines. In this work, a computer code has been modified for simulation of dual-fuel diesel engine combustion process. This model simulates dual-fuel diesel engine combustion by using a Multi-Zone Combustion Model for diesel pilot jet combustion and a conventional spark ignition combustion model for modelling of combustion of premixed gas/air charge. Also, in this model, there are four submodels for prediction of major emission pollutants such as: Unburnt Hydrocarbons, No, Co and soot which are emitted from dual-fuel diesel engine. For prediction of formation and oxidation rates of pollutants, relevant s conventional kinetically-controlled mechanisms and mass balances are used. the model has been verified by experimental data obtained from a heavy-duty truck and bus diesel engines. The comparison shows that, there exist good agreements between the experimental and predicted results from the dual-fuel diesel engine

High-throughput approach to the catalytic combustion of diesel soot

Energy Technology Data Exchange (ETDEWEB)

Iojoiu, Eduard Emil; Bassou, Badr; Guilhaume, Nolven; Farrusseng, David; Desmartin-Chomel, Arnold; Bianchi, Daniel; Mirodatos, Claude [Institut de recherches sur la catalyse et l' environnement de Lyon IRCELYON, UMR5256 CNRS Universite Lyon 1, 2 avenue Albert Einstein, F-69626 Villeurbanne Cedex (France); Lombaert, Karine [Renault, Diesel Innovative Catalytic Materials, Direction de l' Ingenierie Materiaux, 1 Allee Cornuel, 91510 Lardy (France)

2008-08-30

A methodology for the evaluation of diesel soot oxidation catalysts by high-throughput (HT) screening was developed. The optimal experimental conditions (soot amount, catalyst/soot ratio, type of contact, composition and flow rate of gas reactants) ensuring a reliable and reproducible detection of light-off temperatures in a 16 parallel channels reactor were set up. The temperature profile measured in the catalyst/soot bed under TPO conditions when the exothermic combustion of soot takes place was shown to provide an accurate measurement of the ignition. Its reproducibility and relevance were checked. The results obtained with a reference noble metal free catalyst (La{sub 0.8}Cr{sub 0.8}Li{sub 0.2}O{sub 3} perovskite) agree very well with literature data. Qualitative mechanistic features could be derived from these experiments, stressing the likely limiting step of oxygen transfer from catalyst surface to soot particulates to ignite the soot combustion. Ceria material was shown to be more appropriate than perovskite one. From an HT screening of a large diverse library (over 100 mixed oxides catalysts) under optimized conditions, about 10 new formulations were found to perform better than selected noble metal free reference materials. (author)

The individual effects of cetane number, oxygen content or fuel properties on the ignition delay, combustion characteristics, and cyclic variation of a turbocharged CRDI diesel engine – Part 1

International Nuclear Information System (INIS)

Labeckas, Gvidonas; Slavinskas, Stasys; Kanapkienė, Irena

2017-01-01

Highlights: • Diesel-HRD fuel blends involving ethanol (E) or biodiesel (B) were investigated in a turbocharged CRDI engine. • Improved cetane number of fuel blends ambiguously affected the ignition delay and maximum heat release rate. • Increased fuel-bound oxygen content enhanced combustion, heat release and in-cylinder pressure at 2500 rpm. • Fuel properties almost did not change premixed phase, but affected burn angle MBF 50 and the end of combustion. • Burn angles MBF 50 and MBF 90 were 1.0° and 5.7° CADs shorter when using oxygenated blend OE4 (3.6 wt%) at 2000 rpm. - Abstract: The study deals with the effects made by individual variation of cetane number, fuel-oxygen content, or widely differing properties of diesel-HRD fuel blends involving ethanol (E) or biodiesel (B) on the ignition delay, combustion phenomenon, maximum heat release rate, and the cyclic variation of a turbocharged CRDI diesel engine. The most important control factors one after another operated separately in this study to make a difference. Load characteristics were taken when running with a straight diesel and various (18) diesel-HRD fuel blends at maximum torque mode of 2000 rpm and speeds of 1500 and 2500 rpm to provide correct interpretation of the test results. Then, load (bmep) characteristics were plotted as a function of the relative air-fuel ratio (λ) and the analysis of combustion parameters was conducted for the ‘lambda’ values of λ = 1.30, 1.25 and 1.20, at the respective speeds of 1500, 2000 and 2500 rpm. Analysis of changes in the ignition delay, combustion characteristics, and the cyclic variation of parameters when using fuel blends of both origins was performed on comparative bases with the corresponding values measured with ‘base-line’ blends with CN = 51.2 or zero oxygen content and a straight diesel to reveal the potential developing trends. The enhanced cetane number of oxygenated fuels improved combustion and reduced cyclic variation when

Combustion of biodiesel in a large-scale laboratory furnace

International Nuclear Information System (INIS)

Pereira, Caio; Wang, Gongliang; Costa, Mário

2014-01-01

Combustion tests in a large-scale laboratory furnace were carried out to assess the feasibility of using biodiesel as a fuel in industrial furnaces. For comparison purposes, petroleum-based diesel was also used as a fuel. Initially, the performance of the commercial air-assisted atomizer used in the combustion tests was scrutinized under non-reacting conditions. Subsequently, flue gas data, including PM (particulate matter), were obtained for various flame conditions to quantify the effects of the atomization quality and excess air on combustion performance. The combustion data was complemented with in-flame temperature measurements for two representative furnace operating conditions. The results reveal that (i) CO emissions from biodiesel and diesel combustion are rather similar and not affected by the atomization quality; (ii) NO x emissions increase slightly as spray quality improves for both liquid fuels, but NO x emissions from biodiesel combustion are always lower than those from diesel combustion; (iii) CO emissions decrease rapidly for both liquid fuels as the excess air level increases up to an O 2 concentration in the flue gas of 2%, beyond which they remain unchanged; (iv) NO x emissions increase with an increase in the excess air level for both liquid fuels; (v) the quality of the atomization has a significant impact on PM emissions, with the diesel combustion yielding significantly higher PM emissions than biodiesel combustion; and (vi) diesel combustion originates PM with elements such as Cr, Na, Ni and Pb, while biodiesel combustion produces PM with elements such as Ca, Mg and Fe. - Highlights: • CO emissions from biodiesel and diesel tested are similar. • NO x emissions from biodiesel tested are lower than those from diesel tested. • Diesel tested yields significantly higher PM (particulate matter) emissions than biodiesel tested. • Diesel tested originates PM with Cr, Na, Ni and Pb, while biodiesel tested produces PM with Ca, Mg and Fe

Numerical investigation on the combined effects of varying piston bowl geometries and ramp injection rate-shapes on the combustion characteristics of a kerosene-diesel fueled direct injection compression ignition engine

International Nuclear Information System (INIS)

Tay, Kun Lin; Yang, Wenming; Zhao, Feiyang; Yu, Wenbin; Mohan, Balaji

2017-01-01

Highlights: • Effect of injection rate-shaping on heat-release is significant with less turbulence. • Two peak heat-releases are seen for the shallow-depth re-entrant piston. • Significant combustion phasing occurs with kerosene usage and high turbulence. - Abstract: In this work, the combustion characteristics of a direct injection compression ignition (DICI) engine fueled with kerosene-diesel blends, using different piston bowl geometries together with varying injection rate-shapes were investigated. A total of three combustion bowl geometries, namely the omega combustion chamber (OCC), the shallow-depth combustion chamber (SCC) and the shallow-depth re-entrant combustion chamber (SRCC), were used together with six different ramp injection rate-shapes and pure diesel, kerosene-diesel and pure kerosene fuels. It is seen that the SRCC geometry, which has the shortest throat length, gives the highest turbulence kinetic energy (TKE) and this resulted in two peak heat-releases, with a primary peak heat-release during the premixed combustion phase and a secondary peak heat-release during the mixing-controlled combustion phase. In addition, the SCC geometry gives rather distinct premixed combustion and mixing-controlled combustion phases due to the fact that combustion is predominantly controlled by the injected fuel spray itself because of less turbulence. Also, when kerosene is used in place of diesel, the heat-release during the premixed combustion phase increases and diminishes during the mixing-controlled and late combustion phases. It is interesting to note that the effect of injection rate-shaping on the heat-release rate is more obvious for bowl geometries that generate less TKE. Moreover, bowl geometries that generate higher TKEs as well as fuels with lower viscosities generally give lower carbon monoxide (CO) emissions and higher nitrogen oxide (NO) emissions. More importantly, it is possible to achieve low NO and CO emissions simultaneously by using the

Field test of two high-pressure, direct-contact downhole steam generators. Volume I. Air/diesel system

Energy Technology Data Exchange (ETDEWEB)

Marshall, B.W.

1983-05-01

As a part of the Project DEEP STEAM to develop technology to more efficiently utilize steam for the recovery of heavy oil from deep reservoirs, a field test of a downhole steam generator (DSG) was performed. The DSG burned No. 2 diesel fuel in air and was a direct-contact, high pressure device which mixed the steam with the combustion products and injected the resulting mixture directly into the oil reservoir. The objectives of the test program included demonstration of long-term operation of a DSG, development of operational methods, assessment of the effects of the steam/combustion gases on the reservoir and comparison of this air/diesel DSG with an adjacent oxygen/diesel direct contact generator. Downhole operation of the air/diesel DSG was started in June 1981 and was terminated in late February 1982. During this period two units were placed downhole with the first operating for about 20 days. It was removed, the support systems were slightly modified, and the second one was operated for 106 days. During this latter interval the generator operated for 70% of the time with surface air compressor problems the primary source of the down time. Thermal contact, as evidenced by a temperature increase in the production well casing gases, and an oil production increase were measured in one of the four wells in the air/diesel pattern. Reservoir scrubbing of carbon monoxide was observed, but no conclusive data on scrubbing of SO/sub x/ and NO/sub x/ were obtained. Corrosion of the DSG combustor walls and some other parts of the downhole package were noted. Metallurgical studies have been completed and recommendations made for other materials that are expected to better withstand the downhole combustion environment. 39 figures, 8 tables.

Effects of Canola Oil Biodiesel Fuel Blends on Combustion, Performance, and Emissions Reduction in a Common Rail Diesel Engine

Directory of Open Access Journals (Sweden)

Sam Ki Yoon

2014-12-01

Full Text Available In this study, we investigated the effects of canola oil biodiesel (BD to improve combustion and exhaust emissions in a common rail direct injection (DI diesel engine using BD fuel blended with diesel. Experiments were conducted with BD blend amounts of 10%, 20%, and 30% on a volume basis under various engine speeds. As the BD blend ratio increased, the combustion pressure and indicated mean effective pressure (IMEP decreased slightly at the low engine speed of 1500 rpm, while they increased at the middle engine speed of 2500 rpm. The brake specific fuel consumption (BSFC increased at all engine speeds while the carbon monoxide (CO and particulate matter (PM emissions were considerably reduced. On the other hand, the nitrogen oxide (NOx emissions only increased slightly. When increasing the BD blend ratio at an engine speed of 2000 rpm with exhaust gas recirculation (EGR rates of 0%, 10%, 20%, and 30%, the combustion pressure and IMEP tended to decrease. The CO and PM emissions decreased in proportion to the BD blend ratio. Also, the NOx emissions decreased considerably as the EGR rate increased whereas the BD blend ratio only slightly influenced the NOx emissions.

Dual-fuelling of a direct-injection automotive diesel engine by diesel and compressed natural gas

International Nuclear Information System (INIS)

Pirouzpanah, V.; Mohammadi Kosha, A.; Mosseibi, A.; Moshirabadi, J.; Gangi, A.; Moghadaspour, M.

2000-01-01

Application of Compressed Natural Gas in diesel engines has always been important, especially in the field of automotive engineering. This is due to easy accessibility, better mixing quality and good combustion characteristics of the Compressed Natural Gas fuel. In this study the application of Compressed Natural Gas fuel along with diesel oil in a heavy duty direct-injection automotive diesel engine is experimentally investigated. In order to convert a diesel engine into a diesel-gas one, the so called m ixed diesel-gas a pproach has been used and for this purpose a carbureted Compressed Natural Gas fuel system has been designed and manufactured. For controlling quantity of Compressed Natural Gas, the gas valve is linked to the diesel fuel injection system by means of a set of rods. Then, the dual-fuel system is adjusted so that, at full load conditions, the quantity of diesel fuel is reduced to 20% and 80% of its equivalent energy is substituted by Compressed Natural Gas fuel. Also injection pressure of pilot jet is increased by 11.4%. Performance and emission tests are conducted under variation of load and speed on both diesel and diesel-gas engines. Results show that, with equal power and torque, the diesel-gas engine has the potential to improve overall engine performance and emission. For example, at rated power and speed, fuel economy increases by 5.48%, the amount of smoke decreases by 78%, amount of CO decreases by 64.3% and mean exhaust gas temperature decreases by 6.4%

Hydrogen combustion and exhaust emissions in a supercharged gas engine ignited with micro pilot diesel fuel

Energy Technology Data Exchange (ETDEWEB)

Tomita, E.; Kawahara, N. [Okayama Univ., Okayama (Japan); Roy, M.M. [Rajshahi Univ. of Engineering and Technology, Rajshahi (Bangladesh)

2009-07-01

A hydrogen combustion and exhaust emissions in a supercharged gas engine ignited with micro pilot diesel fuel was discussed in this presentation. A schematic diagram of the experimental study was first presented. The single cylinder, water-cooled, supercharged test engine was illustrated. Results were presented for the following: fuel energy and energy share (hydrogen and diesel fuel); pressure history and rate of heat release; engine performance and exhaust emissions; effect of nitrogen dilution on heat value per cycle; effect of N{sub 2} dilution on pressure history and rate of heat release; and engine performance and exhaust emissions. This presentation demonstrated that smooth and knock-free engine operation results from the use of hydrogen in a supercharged dual-fuel engine for leaner fuel-air equivalence ratios maintaining high thermal efficiency. It was possible to attain mor3 than 90 per cent hydrogen-energy substitution to the diesel fuel with zero smoke emissions. figs.

Hydrogen combustion and exhaust emissions in a supercharged gas engine ignited with micro pilot diesel fuel

International Nuclear Information System (INIS)

Tomita, E.; Kawahara, N.; Roy, M.M.

2009-01-01

A hydrogen combustion and exhaust emissions in a supercharged gas engine ignited with micro pilot diesel fuel was discussed in this presentation. A schematic diagram of the experimental study was first presented. The single cylinder, water-cooled, supercharged test engine was illustrated. Results were presented for the following: fuel energy and energy share (hydrogen and diesel fuel); pressure history and rate of heat release; engine performance and exhaust emissions; effect of nitrogen dilution on heat value per cycle; effect of N 2 dilution on pressure history and rate of heat release; and engine performance and exhaust emissions. This presentation demonstrated that smooth and knock-free engine operation results from the use of hydrogen in a supercharged dual-fuel engine for leaner fuel-air equivalence ratios maintaining high thermal efficiency. It was possible to attain mor3 than 90 per cent hydrogen-energy substitution to the diesel fuel with zero smoke emissions. figs.

Scrutinizing the combustion, performance and emissions of safflower biodiesel–kerosene fueled diesel engine used as power source for a generator

International Nuclear Information System (INIS)

Aydın, Hüseyin

2016-01-01

Highlights: • Effects of kerosene addition to biodiesel in a diesel engine were investigated. • S90&K10, S75&K25 and S50&K50 were tested and comparisons have been made with D2. • Patterns of combustion parameters have found be quite similar for blend fuels and D2. • The highest efficiency value is obtained for S50&K50 blend. • HC emissions a bit increased and NOx emissions were decreased. - Abstract: When neat biodiesel or its blends with diesel fuel that contain high amounts of biodiesel are used in diesel engines some operational problems such as poor injection, bad atomization and incomplete combustion occur mainly due to higher viscosity and surface tension. Engine problems with the use of biodiesel–fuel blends that contain higher percentages of biodiesel need to be solved in order to utilize the advantages of biodiesel in environmental and economical ways. The mentioned problems can also be solved by blending biodiesel with another low density or viscosity fuel such as kerosene. In present study biodiesel was produced from safflower oil. S90&K10, S75&K25 and S50&K50 were prepared by blending biodiesel with kerosene. A 4 cylinder diesel engine that was used to drive an electric generator was used to deeply investigate the similarity of combustion, performance and emission characteristics of the blend fuels to D2. All experiments were carried out at constant loads of 3.6, 7.2 and 10.8 kW generated powers. Patterns of combustion parameters found to be quite similar for blends and D2 fuel. NO_x emissions were considerably decreased with percentages of 68.2%, 56.9% and 55.1% for S50&K50, S75&K25 and S90&K10, respectively while unburned HC emissions were a bit increased. Mass fuel consumption and BSFC were slightly increased for S75&K25 and S90&K10, but they were decreased with an average increase in BTE by 3.84% for S50&K50 fuel when compared to D2. Eventually, it was concluded that high percentages of safflower oil biodiesel can be a potential

Improvement of combustion in a direct injection diesel engine by the use of a combustion-hole injection nozzle; Kumiawase funko nozzle ni yoru chokusetsu funshashiki diesel engine no nensho kaizen

Energy Technology Data Exchange (ETDEWEB)

Shoji, T. [Mitsubishi Motors Corp., Tokyo (Japan); Kamimoto, T. [Tokyo Institute of Technology, Tokyo (Japan)

1998-04-25

Suppression of pre-mixed combustion and activation of diffusion combustion in DI diesel engines are known to be effective in reducing both NOx and fuel consumption. To achieve this concept, the authors have proposed a new type of fuel injection nozzle named combination-hole nozzle. This nozzle has very small holes with a diameter of 0.13 mm below (sub holes) for reducing ignition delay and normal holes (main holes) for keeping reasonable injection duration. The experiments conducted with a single cylinder research engine revealed that the combination-hole nozzle reduced the ignition delay and the peak value of the rate of heat release during the premixed combustion by 10% and 40% respectively compared with the experimental results of conventional nozzles and that the trade-off curve between NOx and fuel consumption sifted to the low level corner at half and full load conditions at a low engine speed. The reason for this improvement was investigated by the measurement of flame temperature distribution in the combustion chamber by means of the two colors method. The result revealed that the flame temperature in regions between sub and main hole`s flames of the nozzle was lower than that of the flames of a conventional nozzle at a full load and a low speed condition. 13 refs., 10 figs., 3 tabs.

Performance, combustion timing and emissions from a light duty vehicle at different altitudes fueled with animal fat biodiesel, GTL and diesel fuels

International Nuclear Information System (INIS)

Ramos, Ángel; García-Contreras, Reyes; Armas, Octavio

2016-01-01

Highlights: • Effects of altitude, alternative fuels and driving conditions on emissions have been studied. • Combustion timing was studied by means of on-line thermodynamic diagnosis. • Altitude particularly increases the combustion duration of paraffinic fuels. • Altitude increases NOx emissions more than ten times compared to the sea level. • Effect of fuels on particulate matter is masked when diesel particle filters work efficiently. - Abstract: The altitude effect on performance, emissions and thermodynamic diagnosis under real world driving conditions has been evaluated using two alternative fuels and a diesel fuel. Three places, at different altitudes, were selected for the tests, from 0 to 2500 m above the sea level. Besides, two type of circuits (Urban and Extra-urban) have been selected in order to evaluate these two driving pattern conditions. A light duty diesel vehicle equipped with the same after-treatment system as Euro 5 engines was used as test vehicle. Thermodynamic diagnosis shows that, when the engine works with two pre-injection events (mainly at high altitude and without EGR) the ignition delay agrees of the cetane number of fuels. At urban conditions, altitude increases the combustion duration of all fuels and particularly with paraffinic fuels. The effect of altitude on THC and CO emissions is not noticeable, but at high altitude, NOx emissions during extra-urban tests were around three times higher than those from testing along the urban circuit. Besides, compared to circuits next to the sea level, these emissions at both circuits (urban and extra-urban) were around ten times higher, respectively, than the limits established by the Euro standards. The effect of fuels on pollutant emissions was masked by the variability associated to real driving conditions.

Study on Combustion Performance of Diesel Engine Fueled by Synthesized Waste Cooking Oil Biodiesel Blends

Directory of Open Access Journals (Sweden)

Duraid F. Maki

2018-02-01

Full Text Available The waste cooking oil or used cooking oil is the best source of biodiesel synthesizing because it enters into the so-called W2E field whereas not only get rid of the used cooking oils but produce energy from waste fuel. In this study, biodiesel was synthesized from the used cooking oil and specifications are tested. From 1 liter of used cooking oil, 940 ml is gained. The remaining of liter is glycerin and water. Blend of 20% of biodiesel with 80% of net diesel by volume is formed. Blends of 100% diesel and 100% biodiesel are prepared too. The diesel engine combustion performance is studied. Brake thermal efficiency, brake specific fuel consumption, volumetric efficiency, mean effective pressure, and engine outlet temperature. Cylinder pressure variation with crank angle is analyzed. At last not least, the concentrations of hydro carbon and nitrogen pollutants are measured. The results showed significant enhancement in engine power and pollutant gases emitted. There is positive compatible with other critical researches.

Experimental investigation and combustion analysis of a direct injection dual-fuel diesel-natural gas engine

Energy Technology Data Exchange (ETDEWEB)

Carlucci, A.P.; De Risi, A.; Laforgia, D.; Naccarato, F. [Department of Engineering for Innovation, University of Salento, CREA, via per Arnesano, 73100 Lecce (Italy)

2008-02-15

A single-cylinder diesel engine has been converted into a dual-fuel engine to operate with natural gas together with a pilot injection of diesel fuel used to ignite the CNG-air charge. The CNG was injected into the intake manifold via a gas injector on purpose designed for this application. The main performance of the gas injector, such as flow coefficient, instantaneous mass flow rate, delay time between electrical signal and opening of the injector, have been characterized by testing the injector in a constant-volume optical vessel. The CNG jet structure has also been characterized by means of shadowgraphy technique. The engine, operating in dual-fuel mode, has been tested on a wide range of operating conditions spanning different values of engine load and speed. For all the tested operating conditions, the effect of CNG and diesel fuel injection pressure, together with the amount of fuel injected during the pilot injection, were analyzed on the combustion development and, as a consequence, on the engine performance, in terms of specific emission levels and fuel consumption. (author)

Development and Validation of 3D-CFD Injection and Combustion Models for Dual Fuel Combustion in Diesel Ignited Large Gas Engines

Directory of Open Access Journals (Sweden)

Lucas Eder

2018-03-01

Full Text Available This paper focuses on improving the 3D-Computational Fluid Dynamics (CFD modeling of diesel ignited gas engines, with an emphasis on injection and combustion modeling. The challenges of modeling are stated and possible solutions are provided. A specific approach for modeling injection is proposed that improves the modeling of the ballistic region of the needle lift. Experimental results from an inert spray chamber are used for model validation. Two-stage ignition methods are described along with improvements in ignition delay modeling of the diesel ignited gas engine. The improved models are used in the Extended Coherent Flame Model with the 3 Zones approach (ECFM-3Z. The predictive capability of the models is investigated using data from single cylinder engine (SCE tests conducted at the Large Engines Competence Center (LEC. The results are discussed and further steps for development are identified.

Effects of premixed diethyl ether (DEE) on combustion and exhaust emissions in a HCCI-DI diesel engine

International Nuclear Information System (INIS)

Cinar, Can; Can, Ozer; Sahin, Fatih; Yucesu, H. Serdar

2010-01-01

In this study, the effects of premixed ratio of diethyl ether (DEE) on the combustion and exhaust emissions of a single-cylinder, HCCI-DI engine were investigated. The experiments were performed at the engine speed of 2200 rpm and 19 N m operating conditions. The amount of the premixed DEE was controlled by a programmable electronic control unit (ECU) and the DEE injection was conducted into the intake air charge using low pressure injector. The premixed fuel ratio (PFR) of DEE was changed from 0% to 40% and results were compared to neat diesel operation. The percentages of premixed fuel were calculated from the energy ratio of premixed DEE fuel to total energy rate of the fuels. The experimental results show that single stage ignition was found with the addition of premixed DEE fuel. Increasing and phasing in-cylinder pressure and heat release were observed in the premixed stage of the combustion. Lower diffusion combustion was also occurred. Cycle-to cycle variations were very small with diesel fuel and 10% DEE premixed fuel ratio. Audible knocking occurred with 40% DEE premixed fuel ratio. NO x -soot trade-off characteristics were changed and improvements were found simultaneously. NO x and soot emissions decreased up to 19.4% and 76.1%, respectively, while exhaust gas temperature decreased by 23.8%. On the other hand, CO and HC emissions increased.

Investigating the reactivity controlled compression ignition (RCCI) combustion strategy in a natural gas/diesel fueled engine with a pre-chamber

International Nuclear Information System (INIS)

Salahi, Mohammad Mahdi; Esfahanian, Vahid; Gharehghani, Ayatallah; Mirsalim, Mostafa

2017-01-01

Highlights: • A novel combustion strategy, RCCI with a pre-chamber, is proposed and investigated. • The proposed strategy extends the RCCI operating range to use less intake air temperatures. • The new concept extends the RCCI operating range to use lower portions of the active fuel. • The proposed strategy is sensitive to engine load and is more efficient for high loads. - Abstract: Reactivity controlled compression ignition (RCCI) concept has been proven to be a promising combustion mode for the next generations of internal combustion engines. This strategy is still subject of extensive studies to overcome its operational limitations. In the present work, the effect of using a pre-chamber to extend some operating ranges in a RCCI engine is investigated using coupled multidimensional computational fluid dynamics (CFD) with detailed chemical kinetic mechanisms. To accomplish this, the combustion and flow field in a single cylinder engine with a pre-chamber, working in RCCI mode and fueled with natural gas/diesel are numerically modeled. Experimental data is used to validate the simulation results and then, combustion characteristics and engine emissions in some various operating regions, in terms of initial temperature, fuel equivalence ratio and portions of the two fuels are discussed. The results reveal that the proposed strategy provides the ability to extend the engine operating ranges to use lower intake temperatures, even to 50 K lower for some cases, and also using a larger portion of natural gas instead of diesel fuel. On the other hand, the new strategy could result in incomplete combustion and formation of related emissions in low loads, but for higher engine loads it shows better combustion characteristics.

A numerical study on the effect of various combustion bowl parameters on the performance, combustion, and emission behavior on a single cylinder diesel engine.

Science.gov (United States)

Balasubramanian, Dhinesh; Sokkalingam Arumugam, Sabari Rajan; Subramani, Lingesan; Joshua Stephen Chellakumar, Isaac JoshuaRamesh Lalvani; Mani, Annamalai

2018-01-01

A numerical study was carried out to study the effect of various combustion bowl parameters on the performance behavior, combustion characteristics, and emission magnitude on a single cylinder diesel engine. A base combustion bowl and 11 different combustion bowls were created by varying the aspect ratio, reentrancy ratio, and bore to bowl ratio. The study was carried out at engine rated speed and a full throttle performance condition, without altering the compression ratio. The results revealed that the combustion bowl parameters could have a huge impact on the performance behavior, combustion characteristics, and emission magnitude of the engine. The bowl parameters, namely throat diameter and toroidal radius, played a crucial role in determining the performance behavior of the combustion bowls. It was observed that the combustion bowl parameters, namely central pip distance, throat diameter, and bowl depth, also could have an impact on the combustion characteristics. And throat diameter and toroidal radius, central pip distance, and toroidal corner radius could have a consequent effect on the emission magnitude of the engine. Of the different combustion bowls tested, combustion bowl 4 was preferable to others owing to the superior performance of 3% of higher indicated mean effective pressure and lower fuel consumption. Interestingly, trade-off for NO x emission was higher only by 2.85% compared with the base bowl. The sensitivity analysis proved that bowl depth, bowl diameter, toroidal radius, and throat diameter played a vital role in the fuel consumption parameter and emission characteristics even at the manufacturing tolerance variations.

Performance evaluation of small scale internal combustion engine with mixtures for diesel oil-palm oil; Avaliacao do desempenho do motor de combustao interna de pequeno porte com misturas oleo diesel - oleo de dende

Energy Technology Data Exchange (ETDEWEB)

Seye, Omar; Souza, Rubem Cesar Rodrigues [Universidade Federal do Amazonas (CDEAM/UFAM), Manaus, AM (Brazil). Centro de Desenvolvimento Energetico Amazonico], Emails: Seye62omar@yahoo.com, rcsouza@internext.com.br

2006-07-01

This work aims at the performance evaluation of the Cummins 4B -3.9, an internal combustion engine of maximum power 75 hp (56.6 kW) for small scale power generation, burning different mixtures of diesel fuel and palm oil. The palm oil in nature is mixed manually, what unfortunately will influence the engine performance as it hinders the combustion. The test protocol will include the biodiesel, later on. The emissions were assessed for several proportions of mixture diesel/palm oil covering the strip from 0 to 20% and the results were compared to the engine performance when it operates with diesel only. The motor is coupled to a dynamometer, whose operation consists of the acceleration and deceleration of water in order to simulate the effect of a load being applied to the motor. The system is controlled by the software LT commander that allows the start up and the shutdown of the engine from the screen of the computer that also monitors the following parameters as speed of rotation of the motor (RPM), applied torque (N-m), potency (hp), temperature of the lubricating oil, temperature of the water in the entrance and exit of the motor, and temperature of the environment (deg C), pressures of the lubricating oil and of opening of the injector (mBar). While a flow meter coupled to the piping measures the consumption of fuel, the gas analyzer ECHO Line 6000 it monitors the concentration and temperature of carbon monoxide (CO) (ppm), nitric oxide (NO) (ppm), nitrogen dioxide (NO{sub 2}), (ppm), sulfur dioxide (SO{sub 2}) (ppm) and Oxygen (O{sub 2}) (%) in the exhaust gases. This equipment also determines the combustion parameters as excess of air and the efficiency. The technical results present the efficiency variation, the pressure of the fuel, monoxide carbon, NOx emissions, Oxygen content in the exhaust gases, for the different mixture proportions. Furthermore, the results of economic viability show generation cost values of US$ 135,66/MWh for the motor operating

Comparison of soot formation for diesel and jet-a in a constant volume combustion chamber using two-color pyrometry

KAUST Repository

Jing, Wei; Roberts, William L.; Fang, Tiegang

2014-01-01

The measurement of the two-color line of sight soot and KL factor for NO.2 diesel and jet-A fuels was conducted in an optical constant volume combustion chamber by using a high speed camera under 1000 K ambient temperature and varied oxygen

Update on Engine Combustion Research at Sandia National Laboratories

International Nuclear Information System (INIS)

Jay Keller; Gurpreet Singh

2001-01-01

The objectives of this paper are to describe the research efforts in diesel engine combustion at Sandia National Laboratories' Combustion Research Facility and to provide recent experimental results. We have four diesel engine experiments supported by the Department of Energy, Office of Heavy Vehicle Technologies: a one-cylinder version of a Cummins heavy-duty engine, a diesel simulation facility, a one-cylinder Caterpillar engine to evaluate combustion of alternative fuels, and a homogeneous-charge, compression ignition (HCCI) engine. Recent experimental results of diesel combustion research will be discussed and a description will be given of our HCCI experimental program and of our HCCI modeling work

Performance, combustion, and emission characteristics of a diesel engine fueled by biodiesel-diesel mixtures with multi-walled carbon nanotubes additives

International Nuclear Information System (INIS)

El-Seesy, Ahmed I.; Abdel-Rahman, Ali K.; Bady, Mahmoud; Ookawara, S.

2017-01-01

Highlights: • Considerable improvements in the combustion of JB20D50MWCNTs compared to pure JB20D. • p_m_a_x, dp/dθ_m_a_x and dQg/dθ_m_a_x increased by 7%, 4% and 4%, respectively. • Brake specific fuel consumption decreased by 15%. • NO_x, CO, and UHC reduced by 35%, 50%, and 60%, respectively. • Significant enhancement in all engine performance was achieved at a concentration of 40 mg/l. - Abstract: In this work, the effects of adding Multi-Walled Carbon nanotubes (MWCNTs) to Jojoba methyl ester-diesel blended fuel (JB20D) on performance, combustion and emissions characteristics of a compression-ignition engine were experimentally investigated. The JB20D with 10, 20, 30, 40 and 50 mg/l of MWCNTs were examined at different engine loads and speeds. Compared to pure diesel, the use of JB20D without MWCNTs caused a slight decrease in the engine performance and an increase in the engine emissions at most examined conditions. The MWCNTs–B20D blended fuel attained a maximum increase of 16% in the brake thermal efficiency and a decrease of 15% in the brake specific fuel consumption at the dose level of 50 mg/l compared to JB20D. The MWCNTs-JB20D blended fuel also brought about an enhancement in combustion characteristics where the peak cylinder pressure, the maximum rate of pressure rise and the peak heat release rate were increased by 7%, 4%, and 4%, respectively, at the same dose level. According to the measured emissions, a significant reduction of engine emissions was achieved at the dose level of 20 mg/l, where NO_x, CO, and UHC were reduced by 35%, 50%, and 60%, respectively. According to the obtained results, the recommended concentration of MWCNTs in JB20D was concluded to be 40 mg/l, which could give significant improvements in overall the parameters of engine performance and emissions with a good balance between them.

PERFORMANCE ANALYSIS OF 1,4 DIOXANE-ETHANOL-DIESEL BLENDS ON DIESEL ENGINES WITH AND WITHOUT THERMAL BARRIER COATING

Directory of Open Access Journals (Sweden)

Chockalingam Sundar Raj

2010-01-01

Full Text Available 1,4 dioxane, a new additive allows the splash blending of ethanol in diesel in a clear solution. The objective of this investigation is to first create a stable ethanol-diesel blended fuel with 10% 1,4 dioxane additive, and then to generate performance, combustion and emissions data for evaluation of different ethanol content on a single cylinder diesel engine with and without thermal barrier coating. Results show improved performance with blends compared to neat fuel for all conditions of the engine. Drastic reduction in smoke density is found with the blends as compared to neat diesel and the reduction is still better for coated engine. NOx emissions were found to be high for coated engines than the normal engine for the blends. The oxygen enriched fuel increases the peak pressure and rate of pressure rise with increase in ethanol ratio and is still superior for coated engine. Heat release pattern shows higher premixed combustion rate with the blends. Longer ignition delay and shorter combustion duration are found with all blends than neat diesel fuel.

Cobalt and KNO{sub 3} supported on alumina catalysts for diesel soot combustion

Energy Technology Data Exchange (ETDEWEB)

Grzona, Claudia B. [25 de mayo 284, INTEQUI-CONICET-UNSL, Facultad de Ingenieria y Ciencias Economico-Sociales, Villa Mercedes, 5730 (Argentina); Lick, Ileana D. [Calle 47 No 257, CINDECA (CCT-LaPlata-CONICET-UNLP), Departamento de Quimica, Facultad de Ciencias Exactas, La Plata, 1900 (Argentina); Castellon, Enrique Rodriguez [Departamento de Quimica Inorganica, Cristalografia y Mineralogia, Facultad de Ciencias, Universidad de Malaga, Campus de Teatinos, Malaga, 29071 (Spain); Ponzi, Marta I. [25 de mayo 284, INTEQUI-CONICET-UNSL, Facultad de Ingenieria y Ciencias Economico-Sociales, Villa Mercedes, 5730 (Argentina); Ponzi, Esther N., E-mail: eponzi@quimica.unlp.edu.ar [Calle 47 No 257, CINDECA (CCT-LaPlata-CONICET-UNLP), Departamento de Quimica, Facultad de Ciencias Exactas, La Plata, 1900 (Argentina)

2010-10-01

The catalytic combustion of diesel soot was studied in the presence of fresh and aged catalysts: Co/Al{sub 2}O{sub 3}, KNO{sub 3}/Al{sub 2}O{sub 3} and Co/KNO{sub 3}/Al{sub 2}O{sub 3}. The catalysts were prepared by impregnation using nitrate solutions. The catalysts were characterized by X-ray diffraction, thermal programmed reduction, vibrational spectroscopy and X-ray photoelectron spectroscopy. Fresh and aged catalysts present high activity in presence of O{sub 2} and O{sub 2}/NO. The values of the combustion temperature decrease more than 200 deg. C with respect to that observed in the process without catalysis. The activity is associated with the presence of KNO{sub 3} and the role of this salt can be attributed to the contribution of NO{sub 3}{sup -}/NO{sub 2}{sup -} redox cycle.

Modeling the effects of late cycle oxygen enrichment on diesel engine combustion and emissions

International Nuclear Information System (INIS)

Mather, D. K.; Foster, D. E.; Poola, R. B.; Longman, D. E.; Chanda, A.; Vachon, T. J.

2002-01-01

A multidimensional simulation of Auxiliary Gas Injection (AGI) for late cycle oxygen enrichment was exercised to assess the merits of AGI for reducing the emissions of soot from heavy duty diesel engines while not adversely affecting the NO(sub x) emissions of the engine. Here, AGI is the controlled enhancement of mixing within the diesel engine combustion chamber by high speed jets of air or another gas. The engine simulated was a Caterpillar 3401 engine. For a particular operating condition of this engine, the simulated soot emissions of the engine were reduced by 80% while not significantly affecting the engine-out NO(sub x) emissions compared to the engine operating without AGI. The effects of AGI duration, timing, and orientation are studied to confirm the window of opportunity for realizing lower engine-out soot while not increasing engine out NO(sub x) through controlled enhancement of in-cylinder mixing. These studies have shown that this window occurs during the late combustion cycle, from 20 to 60 crank angle degrees after top-dead-center. During this time, the combustion chamber temperatures are sufficiently high that soot oxidation increases in response in increased mixing, but the temperature is low enough that NO(sub x) reactions are quenched. The effect of the oxygen composition of the injected air is studied for the range of compositions between 21% and 30% oxygen by volume. This is the range of oxygen enrichment that is practical to produce from an air separation membrane. Simulations showed that this level of oxygen enrichment is insufficient to provide an additional benefit by either increasing the level of soot oxidation or prolonging the window of opportunity for increasing soot oxidation through enhanced mixing

Determination of performance and combustion characteristics of a diesel engine fueled with canola and waste palm oil methyl esters

Energy Technology Data Exchange (ETDEWEB)

Ozsezen, Ahmet Necati [Department of Automotive Engineering Technology, Kocaeli University, 41380 Izmit (Turkey); Alternative Fuels R and D Center, Kocaeli University, 41040 Izmit (Turkey); Canakci, Mustafa, E-mail: canakci@kocaeli.edu.t [Department of Automotive Engineering Technology, Kocaeli University, 41380 Izmit (Turkey); Alternative Fuels R and D Center, Kocaeli University, 41040 Izmit (Turkey)

2011-01-15

In this study, the performance, combustion and injection characteristics of a direct injection diesel engine have been investigated experimentally when it was fueled with canola oil methyl ester (COME) and waste (frying) palm oil methyl ester (WPOME). In order to determine the performance and combustion characteristics, the experiments were conducted at constant engine speeds under the full load condition of the engine. The results indicated that when the test engine was fueled with WPOME or COME instead of petroleum based diesel fuel (PBDF), the brake power reduced by 4-5%, while the brake specific fuel consumption increased by 9-10%. On the other hand, methyl esters caused reductions in carbon monoxide (CO) by 59-67%, in unburned hydrocarbon (HC) by 17-26%, in carbon dioxide (CO{sub 2}) by 5-8%, and smoke opacity by 56-63%. However, both methyl esters produced more nitrogen oxides (NO{sub x}) emissions by 11-22% compared with those of the PBDF over the speed range.

Determination of performance and combustion characteristics of a diesel engine fueled with canola and waste palm oil methyl esters

International Nuclear Information System (INIS)

Ozsezen, Ahmet Necati; Canakci, Mustafa

2011-01-01

In this study, the performance, combustion and injection characteristics of a direct injection diesel engine have been investigated experimentally when it was fueled with canola oil methyl ester (COME) and waste (frying) palm oil methyl ester (WPOME). In order to determine the performance and combustion characteristics, the experiments were conducted at constant engine speeds under the full load condition of the engine. The results indicated that when the test engine was fueled with WPOME or COME instead of petroleum based diesel fuel (PBDF), the brake power reduced by 4-5%, while the brake specific fuel consumption increased by 9-10%. On the other hand, methyl esters caused reductions in carbon monoxide (CO) by 59-67%, in unburned hydrocarbon (HC) by 17-26%, in carbon dioxide (CO 2 ) by 5-8%, and smoke opacity by 56-63%. However, both methyl esters produced more nitrogen oxides (NO x ) emissions by 11-22% compared with those of the PBDF over the speed range.

Genotoxicity of diesel engine emissions during combustion of vegetable oils, mineral oil, and their blends; Gentoxizitaet von Dieselmotoremissionen bei Verbrennung von Pflanzenoelen, Mineraloeldiesel und deren Mischkraftstoffen

Energy Technology Data Exchange (ETDEWEB)

Buenger, Joern

2013-07-09

High particle emissions and strong mutagenic effects were observed after combustion of vegetable oil in diesel engines. This study tested the hypothesis that these results are affected by the amount of unsaturated or polyunsaturated fatty acids of vegetable oils and that blends of diesel fuel and vegetable oil are mutagenic. Three different vegetable oils (linseed oil, LO; palm tree oil, PO; rapeseed oil, RO), blends of 20% vegetable oil and 80% diesel fuel (B20) and 50% vegetable oil and 50% diesel fuel (B50) as well as common diesel fuel (DF) were combusted in a heavy duty diesel engine. The exhaust was investigated for particle emissions and its mutagenic effect in comparison to emissions of DF. The engine was operated using European Stationary Cycle. Particle mass was determined gravimetrically while mutagenicity was determined using the bacterial reverse mutation assay with tester strains TA98 and TA100. Combustion of LO caused the largest amount of total particulate matter (TPM). In comparison to DF it particularly raised the soluble organic fraction (SOF). RO presented second highest TPM and SOF, followed by PO which was scarcely above DF. B50 revealed the lowest amount of TPM while B20 reached as high as DF. RO revealed the highest number of mutations of the vegetable oils closely followed by LO. PO was less mutagenic, but still induced stronger effects than DF. B50 showed higher mutagenic potential than B20. While TPM and SOF were strongly correlated with the content of polyunsaturated fatty acids in the vegetable oils, mutagenicity had a significant correlation with the amount of total unsaturated fatty acids. Vegetable oil blends seem to be less mutagenic than the pure oils with a shifted maximum compared to blends with biodiesel and DF. This study supports the hypothesis that numbers of double bounds in unsaturated fatty acids of vegetable oils combusted in diesel engines influence the amount of emitted particles and the mutagenicity of the exhaust. And

Combustion and emissions control in diesel-methane dual fuel engines: The effects of methane supply method combined with variable in-cylinder charge bulk motion

International Nuclear Information System (INIS)

Carlucci, Antonio P.; Laforgia, Domenico; Saracino, Roberto; Toto, Giuseppe

2011-01-01

presence and to calculate an average luminance value over the whole frame. These luminance values, chosen as indicators of the combustion intensity, were represented over crank angle position and, then, an analysis of the resulting curves was performed. Results showed that the charge bulk motion associated to the swirl port, improving the charge mixing of the diesel spray and the propagation of the turbulent flame fronts, is capable to enhance the oxidation of air-methane mixture, both at low and high engine loads. Furthermore, at low loads, the analysis of combustion images and luminance curves showed that methane port injection can significantly affect the intensity and the spreading of the flame during dual fuel combustion, especially when a suitable in-cylinder bulk motion is obtained. Concerning the engine emissions, some correlations with what observed during the analysis of the combustion development were found. Furthermore, it was revealed that, for several combinations of the engine operating parameters, methane port injection was always associated to the lowest emission levels, demonstrating that this methane supply method is a very effective strategy to reduce unburned hydrocarbons and nitric oxides concentrations, especially when implemented with variable intake geometry systems.

Differences in rheological profile of regular diesel and bio-diesel fuel

Directory of Open Access Journals (Sweden)

Jiří Čupera

2010-01-01

Full Text Available Biodiesel represents a promising alternative to regular fossil diesel. Fuel viscosity markedly influences injection, spraying and combustion, viscosity is thus critical factor to be evaluated and monitored. This work is focused on quantifying the differences in temperature dependent kinematic viscosity regular diesel fuel and B30 biodiesel fuel. The samples were assumed to be Newtonian fluids. Vis­co­si­ty was measured on a digital rotary viscometer in a range of 0 to 80 °C. More significant difference between minimum and maximum values was found in case of diesel fuel in comparison with biodiesel fuel. Temperature dependence of both fuels was modeled using several mathematical models – polynomial, power and Gaussian equation. The Gaussian fit offers the best match between experimental and computed data. Description of viscosity behavior of fuels is critically important, e.g. when considering or calculating running efficiency and performance of combustion engines. The models proposed in this work may be used as a tool for precise prediction of rheological behavior of diesel-type fuels.

Influences of diesel pilot injection on ethanol autoignition - a numerical analysis

Science.gov (United States)

Burnete, N. V.; Burnete, N.; Jurchis, B.; Iclodean, C.

2017-10-01

The aim of this study is to highlight the influences of the diesel pilot quantity as well as the timing on the autoignition of ethanol and the pollutant emissions resulting from the combustion process. The combustion concept presented in this paper requires the injection of a small quantity of diesel fuel in order to create the required autoignition conditions for ethanol. The combustion of the diesel droplets injected in the combustion chamber lead to the creation of high temperature locations that favour the autoignition of ethanol. However, due to the high vaporization enthalpy and the better distribution inside the combustion chamber of ethanol, the peak temperature values are reduced. Due to the lower temperature values and the high burning velocity of ethanol (combined with the fact that there are multiple ignition sources) the conditions required for the formation of nitric oxides are not achieved anymore, thus leading to significantly lower NOx emissions. This way the benefits of the Diesel engine and of the constant volume combustion are combined to enable a more efficient and environmentally friendly combustion process.

Effect of small proportion of butanol additive on the performance, emission, and combustion of Australian native first- and second-generation biodiesel in a diesel engine.

Science.gov (United States)

Rahman, Md Mofijur; Rasul, Mohammad Golam; Hassan, Nur Md Sayeed; Azad, Abul Kalam; Uddin, Md Nasir

2017-10-01

This paper aims to investigate the effect of the addition of 5% alcohol (butanol) with biodiesel-diesel blends on the performance, emissions, and combustion of a naturally aspirated four stroke multi-cylinder diesel engine at different engine speeds (1200 to 2400 rpm) under full load conditions. Three types of local Australian biodiesel, namely macadamia biodiesel (MB), rice bran biodiesel (RB), and waste cooking oil biodiesel (WCB), were used for this study, and the data was compared with results for conventional diesel fuel (B0). Performance results showed that the addition of butanol with diesel-biodiesel blends slightly lowers the engine efficiency. The emission study revealed that the addition of butanol additive with diesel-biodiesel blends lowers the exhaust gas temperature (EGT), carbon monoxide (CO), nitrogen oxide (NOx), and particulate matter (PM) emissions whereas it increases hydrocarbon (HC) emissions compared to B0. The combustion results indicated that in-cylinder pressure (CP) for additive added fuel is higher (0.45-1.49%), while heat release rate (HRR) was lower (2.60-9.10%) than for B0. Also, additive added fuel lowers the ignition delay (ID) by 23-30% than for B0. Finally, it can be recommended that the addition of 5% butanol with Australian biodiesel-diesel blends can significantly lower the NOx and PM emissions.

Exhaust gas recirculation – Zero dimensional modelling and characterization for transient diesel combustion control

International Nuclear Information System (INIS)

Asad, Usman; Tjong, Jimi; Zheng, Ming

2014-01-01

Highlights: • Zero-dimensional EGR model for transient diesel combustion control. • Detailed analysis of EGR effects on intake, cylinder charge and exhaust properties. • Intake oxygen validated as an operating condition-independent measure of EGR. • Quantified EGR effectiveness in terms of NOx emission reduction. • Twin lambda sensor technique for estimation of EGR/in-cylinder parameters. - Abstract: The application of exhaust gas recirculation (EGR) during transient engine operation is a challenging task since small fluctuations in EGR may cause larger than acceptable spikes in NOx/soot emissions or deterioration in the combustion efficiency. Moreover, the intake charge dilution at any EGR ratio is a function of engine load and intake pressure, and typically changes during transient events. Therefore, the management of EGR during transient engine operation or advanced combustion cycles (that are inherently less stable) requires a fundamental understanding of the transient EGR behaviour and its impact on the intake charge development. In this work, a zero-dimensional EGR model is described to estimate the transient (cycle-by-cycle) progression of EGR and the time (engine cycles) required for its stabilization. The model response is tuned to a multi-cylinder engine by using an overall engine system time-constant and shown to effectively track the transient EGR changes. The impact of EGR on the actual air–fuel ratio of the cylinder charge is quantified by defining an in-cylinder excess-air ratio that accounts for the oxygen in the recycled exhaust gas. Furthermore, a twin lambda sensor (TLS) technique is implemented for tracking the intake dilution and in-cylinder excess-air ratio in real-time. The modelling and analysis results are validated against a wide range of engine operations, including transient and steady-state low temperature combustion tests

Evaluation of the health impact of nanoparticles emitted from combustion sources: Comprehensive characterization of the physicochemical properties of nanoparticle emissions from wood combustion compliances, car- and ship diesel-engines as well as investigation of their toxicological effects on human lung cells and macrophages.

Science.gov (United States)

Zimmermann, R.; Dittmar, G.; Kanashova, T.; Buters, J.; Öder, S.; Paur, H. R.; Mülhopt, S.; Dilger, M.; Weiss, C.; Harndorf, H.; Stengel, B.; Hirvonen, M. R.; Jokiniemi, J.; Hiller, K.; Sapcariu, S.; Sippula, O.; Streibel, T.; Karg, E.; Weggler, B.; Schnelle-Kreis, J.; Lintelmann, J.; Sklorz, M.; Orasche, J.; Müller, L.; Passig, J.; Gröger, T.; BéruBé, K.; Krebs, T.

2016-12-01

Combustion emissions cause health effects. The HICE-Aerosol and Health project team studies the physicochemical properties as well as biological and toxicological effects on lung cells of combustion particle emissions. The chemical composition and physical parameters thoroughly characterized. Human lung cells are exposed to the diluted combustion exhaust fumes at the air-liquid interface (ALI), allowing a realistic lung-cell exposure by simulation of the lung situation. After exposure, cellular responses of the exposed lung cells are studied by multi-omics molecular biological analyses on transcriptomic, proteomic and metabolomic level. Emissions of wood combustion (log wood, pellet heater), ship diesel engines and car gasoline engines are addressed. Special field deployable ALI-exposition systems in a mobile S2-biological laboratory were set up and applied. Human alveolar epithelial cells (A549, BEAS2B and primary cells) as well as murine macrophages were ALI-exposed to diluted emissions. The cellular effects were then comprehensively characterized (viability, cyto-toxicology, multi-omics effects monitoring) and put in context with the chemical and physical aerosol data. The following order of overall cellular response-strength was observed: A relatively mild cellular effect is observed for the diluted wood combustion emissions. Interestingly the effects-strength for log-wood and pellet burner emissions are similar, although PM-concentrations are much higher for the log-wood heater. Similar mild biological effects are observed for the gasoline car emissions. The ship diesel engine emissions induced the most intense biological responses. A surprising result in this context is, that heavy fuel oil (HFO)-emissions showed lower biological effect strengths than the supposedly cleaner diesel fuel emissions (DF). The HFO-emission contain high concentrations of known toxicants (transition metals, polycyclic aromatics). This result was recently confirmed by experiments

Experimental investigation of gasoline compression ignition combustion in a light-duty diesel engine

Science.gov (United States)

Loeper, C. Paul

Due to increased ignition delay and volatility, low temperature combustion (LTC) research utilizing gasoline fuel has experienced recent interest [1-3]. These characteristics improve air-fuel mixing prior to ignition allowing for reduced emissions of nitrogen oxides (NOx) and soot (or particulate matter, PM). Computational fluid dynamics (CFD) results at the University of Wisconsin-Madison's Engine Research Center (Ra et al. [4, 5]) have validated these attributes and established baseline operating parameters for a gasoline compression ignition (GCI) concept in a light-duty diesel engine over a large load range (3-16 bar net IMEP). In addition to validating these computational results, subsequent experiments at the Engine Research Center utilizing a single cylinder research engine based on a GM 1.9-liter diesel engine have progressed fundamental understanding of gasoline autoignition processes, and established the capability of critical controlling input parameters to better control GCI operation. The focus of this thesis can be divided into three segments: 1) establishment of operating requirements in the low-load operating limit, including operation sensitivities with respect to inlet temperature, and the capabilities of injection strategy to minimize NOx emissions while maintaining good cycle-to-cycle combustion stability; 2) development of novel three-injection strategies to extend the high load limit; and 3) having developed fundamental understanding of gasoline autoignition kinetics, and how changes in physical processes (e.g. engine speed effects, inlet pressure variation, and air-fuel mixture processes) affects operation, develop operating strategies to maintain robust engine operation. Collectively, experimental results have demonstrated the ability of GCI strategies to operate over a large load-speed range (3 bar to 17.8 bar net IMEP and 1300-2500 RPM, respectively) with low emissions (NOx and PM less than 1 g/kg-FI and 0.2 g/kg-FI, respectively), and low

A fully variable, piezo-actuated research injection system as a tool in diesel engine combustion process development; Ein vollvariables, piezoaktuiertes Foschungs-Einspritzsystem als Werkzeug in der dieselmotorischen Brennverfahrensentwicklung

Energy Technology Data Exchange (ETDEWEB)

Meyer, S.; Stegemann, J.; Seebode, J.; Merker, G.P. [Hannover Univ. (Germany). Inst. fuer Technische Verbrennung

2004-07-01

The injection process is a central optimisation approach for low-cost, low-emission diesel engines. An injection system is presented which comprises a pressure modulator and a research injector with piezo-actuated direct actuation of the nozzle. The high flexibility of the system enables systematic investigations of different combustion processes. (orig.) [German] Die Einspritzverlaufsformung als Mittel zur Minimierung von Rohemissionen bleibt auch im heutigen, von Diskussionen und Partikelfilter und Entstickungstechnologien gepraegten Umfeld ein zentraler Optimierungsansatz fuer kostenguenstige und emissionsarme Dieselmotoren. Das hier vorgestellte Einspritzsystem, bestehend aus einer Druckmodulationseinheit und einem Forschungsinjektor mit piezogesteuerter Direktansteuerung der Duesennadel, dient zur Potenzialanalyse einer freien Einspritzverlaufsformung als Mittel zur innermotorischen Brennverfahrensoptimierung. Dank der hohen Flexibilitaet des Systems sind systematische Untersuchungen in Bezug auf unterschiedliche Brennverfahren moeglich. (orig.)

Energy Analysis of a Diesel Engine Using Diesel and Biodiesel from Waste Cooking Oil

Directory of Open Access Journals (Sweden)

S Abbasi

2018-03-01

University. The engine is connected to a dynamometer and after reaching steady state conditions data were obtained (Fig. 1. In thermal balance study, combustion process merely as a process intended to free up energy fuel and the first law of thermodynamics is used (Koochak et al., 2000. The energy contained in fuel converted to useful and losses energies by combustion. Useful energy measured by dynamometer as brake power and losses energy including exhaust emission, cooling system losses and uncontrollable energy losses. Variance analysis of all engine energy balance done by split plot design based on a completely randomized design and the means were compared with each other using Duncan test at 5% probability. Results and Discussion Results showed that, in general, biodiesel use has a significant impact on all components of energy balance. Of total energy from fuel combustion, the share of energy losses to form of exhaust emissions the maximum value in all percentages allocated to biodiesel (Average 51.715 percent with the maximum and minimum amount of B42 (55.982 percent and B0 (46.481 percent, respectively (Fig. 2. Also, fuel blend with 12% biodiesel was diagnosed the best blend because of having the most useful power, having the lowest energy losses through the exhaust and cooling system. Conclusions Using biodiesel produced from waste cooking oil by transesterification process, lead to increase the useful power. The addition of biodiesel to pure diesel cause to significant reduction in the waste energy due to friction. In higher amounts of biodiesel increase energy losses especially through the exhaust and cooling system due to higher viscosity.

Caracterización experimental mediante técnicas ópticas de sprays en combustión con mezclas de combustibles gasolina y diesel

OpenAIRE

ESCOBEDO CARBONELL, PABLO

2017-01-01

Sprays injected into an atmosphere with thermodynamic conditions similar to those occuring inside the cylinder of an internal combustion engine have been characterized motor of ignition for the compression for the automotive is carried out. As fuel, commercial gasoline and diesel blends are used in different proportions, given the potential mixtures have for producing efficient fuels in compression ignition engines, with pollutant emissions lower than those achieved in current diesel engines....

PERFORMANCE AND EMISSIONS OF A HEAVY DUTY DIESEL ENGINE FUELLED WITH PALM OIL BIODIESEL AND PREMIUM DIESEL

Directory of Open Access Journals (Sweden)

HELMER ACEVEDO

2011-01-01

Full Text Available Biodiesel es promocionado como combustible alternativo para sustituir combustibles de origen fósil y reducir emisiones de carbono. Algunos estudios han sido llevados a cabo para estudiar las emisiones de vehículos diesel de baja potencia. Sin embargo, las emisiones sólidas y gaseosas emitidas por vehículos de trabajo operados con biodiesel de palma africana y diesel de bajo contenido de azufre (~ 15 ppm han sido poco estudiadas. El objetivo de este estudio fue determinar el desempeño y emisiones de un motor Diesel Cummins, 4 tiempos, 9.5 litros, 6 cilindros con sistema de inyección "common rail", y sistema de recirculación de gases. El motor desarrolló una menor potencia (10 % cuando fue operado con biodiesel de palma africana. El motor cumplió con la norma ambiental 2004 cuando fue operado con combustible diesel, sin embargo, con biodiesel de palma africana las emisiones de material particulado y los óxidos de nitrógeno estuvieron fuera de norma.

Analysis of fuel spray characteristics for premixed lean diesel combustion; Kihaku yokongo diesel kikan ni okeru nenryo funmu kaiseki

Energy Technology Data Exchange (ETDEWEB)

Sasaki, S; Harada, a; Miyamoto, T; Akagawa, H; Tsujimura, K

1997-10-01

Premixed lean diesel combustion (PREDIC) makes it possible to achieve low NOx emission. It is an important factor to make the homogeneous spray formation for PREDIC. In this paper presents I the effect of the spray dispersion on emission characteristic were analyzed with the spray observation and engine test. Pintle type nozzle, which has different feature from orifice type nozzle, are used to form the hollow cone spray. As a result, the pintle type nozzle having grooves to generate the swirl flow, makes the reduced penetration in comparison with the hole nozzle under low ambient gas pressure. And it could improve THC, CO emissions at low NOx emission condition. 7 refs., 12 figs., 1 tab.

Investigation of diesel engine for low exhaust emissions with different combustion chambers

Directory of Open Access Journals (Sweden)

Ghodke Pundlik R.

2015-01-01

Full Text Available Upcoming stringent Euro-6 emission regulations for passenger vehicle better fuel economy, low cost are the key challenges for engine development. In this paper, 2.2L, multi cylinder diesel engine have been tested for four different piston bowls designed for compression ratio of CR 15.5 to improve in cylinder performance and reduce emissions. These combustion chambers were verified in CFD at two full load points. 14 mode points have been derived using vehicle model run in AVL CRUISE software as per NEDC cycle based on time weightage factor. Base engine with compression ratio CR16.5 for full load performance and 14-mode points on Engine test bench was taken as reference for comparison. The bowl with flat face on bottom corner has shown reduction 25% and 12 % NOx emissions at 1500 and 3750 rpm full load points at same level of Soot emissions. Three piston bowls were tested for full load performance and 14 mode points on engine test bench and combustion chamber ‘C’ has shown improvement in thermal efficiency by 0.8%. Combinations of cooled EGR and combustion chamber ‘C’ with geometrical changes in engine have reduced exhaust NOx, soot and CO emissions by 22%, 9 % and 64 % as compared to base engine at 14 mode points on engine test bench.

Effect of injection pressure on performance, emission, and combustion characteristics of diesel-acetylene-fuelled single cylinder stationary CI engine.

Science.gov (United States)

Srivastava, Anmesh Kumar; Soni, Shyam Lal; Sharma, Dilip; Jain, Narayan Lal

2018-03-01

In this paper, the effect of injection pressure on the performance, emission, and combustion characteristics of a diesel-acetylene fuelled single cylinder, four-stroke, direct injection (DI) diesel engine with a rated power of 3.5 kW at a rated speed of 1500 rpm was studied. Experiments were performed in dual-fuel mode at four different injection pressures of 180, 190, 200, and 210 bar with a flow rate of 120 LPH of acetylene and results were compared with that of baseline diesel operation. Experimental results showed that highest brake thermal efficiency of 27.57% was achieved at injection pressure of 200 bar for diesel-acetylene dual-fuel mode which was much higher than 23.32% obtained for baseline diesel. Carbon monoxide, hydrocarbon, and smoke emissions were also measured and found to be lower, while the NO x emissions were higher at 200 bar in dual fuel mode as compared to those in other injection pressures in dual fuel mode and also for baseline diesel mode. Peak cylinder pressure, net heat release rate, and rate of pressure rise were also calculated and were higher at 200 bar injection pressure in dual fuel mode.

Effect of Variant End of Injection Period on Combustion Process of Biodiesel Combustion

Directory of Open Access Journals (Sweden)

Khalid Amir

2016-01-01

Full Text Available Biodiesel is an alternative fuel as a replacement to the standard diesel fuel in combustion diesel engine. The biodiesel fuel has a significantly influences throughout the combustion process and exhaust emission. The purpose of this research is to investigate the combustion process behavior during the End of Injection (EOI period and operates under variant conditions using Rapid Compression Machine (RCM. Experimental of RCM is used to simulate a combustion process and combustion characteristics of diesel engine combustion. Three types of biodiesel blend which are B5, B10 and B15 were tested at several injection pressures of 80 MPa, 90 MPa and 130 MPa under different ambient temperatures, 750 K to 1100 K. The results of this study showed that the ignition delay slightly reduced with increasing the content of biodiesel blends from B5, B10 and B15 and became more shorten as the injection pressure been enhanced. As the injection pressure increased, the behavior of combustion pressure at end of injection is reduced, radically increased the NOX emission. It is noted that the process of combustion at the end of injection increased as the ambient temperature is rising. In fact, higher initial ambient temperature improved the fuel atomization and mixing process. Under the biodiesel combustion with higher ambient temperature condition, the exhaust emission of CO, O2, and HC became less but increased in NOX emission. Besides, increased in blends of biodiesel ratio are found to enhance the combustion process, resulted a decreased in HC emissions.

Impact of spray spreading and mixture formation on the combustion of biodiesel-diesel blends; Einfluss der Sprayausbreitung und Gemischbildung auf die Verbrennung von Biodiesel-Diesel-Gemischen

Energy Technology Data Exchange (ETDEWEB)

Huettl, Christian

2011-07-01

In many countries, one tries to replace fossil fuels in internal combustion engines at least in part by biofuels. Beyond the environmental discussions on this issue, some technical challenges have to be overcome. It should be remembered that today's automotive engines have become so fuel efficient and low emissions only by a very sophisticated and subtle control of the mixture formation and combustion. For each other, even non-conventional fuel and for each fuel mixture technical adjustments and developments are necessary in order not to give up those achievements again. This especially is true for the total or partial replacement of conventional diesel fuel by biodiesel. Under this aspect, the author of the book under consideration reports on such investigations for various motor conditions under a systematic variation of the amount of biodiesel. It focuses on the observation of the spray spreading, mixing and combustion.

Bioethanol E85 as a fuel for dual fuel diesel engine

International Nuclear Information System (INIS)

Tutak, Wojciech

2014-01-01

Highlights: • An increase in the E85 fraction is changing the nature of the HRR course. • Change of combustion phasing with E85 fraction. • The ignition delay of dual fuel engine decreases with increasing E85 fuel. • Premixed combustion of E85 fuel reduces smoke emissions. - Abstract: This study investigates the potential of E85 fuelling in a diesel engine. Researches were performed using a three-cylinder a direct injection diesel engine. A dual-fuelling technology is implemented such that E85 is introduced into the intake manifold using a port-fuel injector while diesel is injected directly into the cylinder. The primary aim of the study was to determine the operating parameters of the engine powered on E85 bioethanol fuel in dual fuel system. The parameters that were taken into account are: engine efficiency, indicated mean effective pressure, heat release rate, combustion duration and ignition delay, combustion phasing and exhaust toxicity. With E85 fuel participation, NO x and soot emissions were reduced, whereas CO and HC emissions increased considerably. It was found that E85 participation in a combustible mixture reduced the excess air factor for the engine and this led to increased emissions of CO and HC, but decreased emissions of nitrogen oxides and soot

Experimental investigation of CI engine combustion, performance and emissions in DEE–kerosene–diesel blends of high DEE concentration

International Nuclear Information System (INIS)

Patil, K.R.; Thipse, S.S.

2015-01-01

Highlights: • First ever study on DEE–kerosene–diesel blends used in CI engine. • DEE–diesel blends have reduced the trade-off between PM and NOx of diesel engine. • Optimum performance blend has been found as DE15D. • Adulteration effects of kerosene with diesel have also been investigated. • Additions of kerosene with DE15D blend have deteriorated the overall engine performance. - Abstract: An experimental investigation had been carried out to evaluate the effects of oxygenated cetane improver diethyl ether (DEE) blends with kerosene and diesel on the combustion, performance and emission characteristics of a direct injection diesel engine. Initially, 2%, 5%, 8%, 10%, 15%, 20% and 25% DEE (by volume) were blended into diesel. The DEE–diesel blends have reduced the trade-off between PM and NOx of diesel engine and the optimum performance blend has been found as DE15D. Similarly, 5%, 10% and 15% kerosene (by volume) were blended into diesel to investigate the adulteration effect. In addition, a study was carried out to evaluate the effects of kerosene adulteration on DE15D by blending with 5%, 10% and 15% kerosene (by volume). The engine tests were carried out at 10%, 25%, 50%, 75% and 100% of full load for all test fuels. Laboratory fuel tests showed that the DEE is completely miscible with diesel and kerosene in any proportion. It was observed that the density, kinematic viscosity and calorific value of the blends decreases, while the oxygen content and cetane number of the blends increases with the concentration of DEE addition. The experimental test results showed that the DEE–kerosene–diesel blends have low brake thermal efficiency, high brake specific fuel consumption, high smoke at full load, low smoke at part load, overall low NO, almost similar CO, high HC at full load and low HC at part load as compared to DE15D blend

Review of Heavy-Duty Engine Combustion Research at Sandia National Laboratories

International Nuclear Information System (INIS)

Robert W. Carling; Gurpreet Singh

2000-01-01

The objectives of this paper are to describe the research efforts in diesel engine combustion at Sandia National Laboratories' Combustion Research Facility and to provide recent experimental results. We have four diesel engine experiments supported by the Department of Energy, Office of Heavy Vehicle Technologies: a one-cylinder version of a Cummins heavy-duty engine, a diesel simulation facility, a one-cylinder Caterpillar engine to evaluate combustion of alternative fuels, and a homogeneous-charge, compression-ignition (HCCI) engine facility is under development. Recent experimental results to be discussed are: the effects of injection timing and diluent addition on late-combustion soot burnout, diesel-spray ignition and premixed-burn behavior, a comparison of the combustion characteristics of M85 (a mixture of 85% methanol and 15% gasoline) and DF2 (No.2 diesel reference fuel), and a description of our HCCI experimental program and modeling work

IEA combustion agreement : a collaborative task on alternative fuels in combustion

International Nuclear Information System (INIS)

Larmi, M.

2009-01-01

The focus of the alternative fuels in combustion task of the International Energy Agency is on high efficiency engine combustion, furnace combustion, and combustion chemistry. The objectives of the task are to develop optimum combustion for dedicated fuels by fully utilizing the physical and chemical properties of synthetic and renewable fuels; a significant reduction in carbon dioxide, NOx and particulate matter emissions; determine the minimum emission levels for dedicated fuels; and meet future emission standards of engines without or with minimum after-treatment. This presentation discussed the alternative fuels task and addressed issues such as synthetic fuel properties and benefits. The anticipated future roadmap was presented along with a list of the synthetic and renewable engine fuels to be studied, such as neat oxygenates like alcohols and ethers, biogas/methane and gas combustion, fuel blends, dual fuel combustion, high cetane number diesel fuels like synthetic Fischer-Tropsch diesel fuel and hydrogenated vegetable oil, and low CN number fuels. Implementation examples were also discussed, such as fuel spray studies in optical spray bombs; combustion research in optical engines and combustion chambers; studies on reaction kinetics of combustion and emission formation; studies on fuel properties and ignition behaviour; combustion studies on research engines; combustion optimization; implementing the optimum combustion in research engines; and emission measurements. Overall milestone examples and the overall schedule of participating countries were also presented. figs.

Effects of exhaust gas recirculation in diesel engines featuring late PCCI type combustion strategies

International Nuclear Information System (INIS)

D’Ambrosio, S.; Ferrari, A.

2015-01-01

Highlights: • The effects that a high EGR rate can have on PCCI type combustion strategies have been analyzed. • The dependence of engine emissions and combustion noise on EGR has been addressed. • The time histories of the main in-cylinder variables have been plotted for different EGR rates. - Abstract: The influence of exhaust gas recirculation (EGR) has been analyzed considering experimental results obtained from a Euro 5 diesel engine calibrated with an optimized pilot-main double injection strategy. The engine features a late premixed charge compression ignition (PCCI) type combustion mode. Different steady-state key-points that are representative of the engine application in a passenger car over the New European Driving Cycle (NEDC) have been studied. The engine was fully instrumented to obtain a complete overview of the most important variables. The pressure time history in the combustion chamber has been measured to perform calculations with single and three-zone combustion diagnostic models. These models allow the in-cylinder emissions and the temperature of the burned and unburned zones to be evaluated as functions of the crankshaft angle. The EGR mass fraction was experimentally varied within the 0–50% range. The results of the investigation have shown the influence that high EGR rates can have on intake and exhaust temperatures, in-cylinder pressure and heat release rate time histories, engine-out emissions (CO, HC, NO_x, soot), brake specific fuel consumption and combustion noise for a PCCI type combustion strategy. The outputs of the diagnostic models have been used to conduct a detailed analysis of the cause-and-effect relationships between the EGR rate variations and the engine performance. Finally, the effect of the EGR on the cycle-to-cycle variability of the engine torque has been experimentally investigated.

Fast-regenerable sulfur dioxide adsorbents for diesel engine emission control

Science.gov (United States)

Li, Liyu [Richland, WA; King, David L [Richland, WA

2011-03-15

Disclosed herein are sorbents and devices for controlling sulfur oxides emissions as well as systems including such sorbents and devices. Also disclosed are methods for making and using the disclosed sorbents, devices and systems. In one embodiment the disclosed sorbents can be conveniently regenerated, such as under normal exhaust stream from a combustion engine, particularly a diesel engine. Accordingly, also disclosed are combustion vehicles equipped with sulfur dioxide emission control devices.

Investigation of Diesel combustion using multiple injection strategies for idling after cold start of passenger-car engines

Energy Technology Data Exchange (ETDEWEB)

Payri, F.; Broatch, A.; Salavert, J.M.; Martin, J. [CMT-Motores Termicos, Universidad Politecnica de Valencia, Aptdo. 22012, E-46071 Valencia (Spain)

2010-10-15

A comprehensive investigation was carried out in order to better understand the combustion behaviour in a low compression ratio DI Diesel engine when multiple injection strategies are applied just after the engine cold starts in low temperature conditions (idling). More specifically, the aim of this study was twofold: on one hand, to understand the effect of the multiple injection strategies on the indicated mean effective pressure; on the other hand, to contribute to the understanding of combustion stability characterized by the coefficient of variation of indicated mean effective pressure. The first objective was fulfilled by analyzing the rate of heat release obtained by in-cylinder pressure diagnosis. The results showed that the timing of the pilot injection closest to the main injection was the most influential parameter based on the behaviour of the rate of heat release (regardless of the multiple injection strategy applied). For the second objective, the combustion stability was found to be correlated with the combustion centroid angle. The results showed a trend between them and the existence of a range of centroid angles where the combustion stability is strong enough. In addition, it was also evident that convenient split injection allows shifting the centroid to such a zone and improves combustion stability after start. (author)

An assessment on performance, emission and combustion characteristics of single cylinder diesel engine powered by Cymbopogon flexuosus biofuel

International Nuclear Information System (INIS)

Dhinesh, B.; Isaac JoshuaRamesh Lalvani, J.; Parthasarathy, M.; Annamalai, K.

2016-01-01

Highlights: • Cymbopogon Flexuosus biofuel is used as an alternative energy source. • Cymbopogon flexuosus biofuel 20% + Diesel 80% blend profile stayed close to diesel. • Resulting in higher thermal efficiency and reduced fuel consumption. • Reduced hydrocarbon, carbon monoxide and smoke emission. • Oxides of nitrogen and carbon di-oxide emission was marginally higher. - Abstract: The novelty of this manuscript is that it discusses about the experimental analysis of a new biofuel feedstock as an alternative fuel that has not drawn much attention among the researchers. An exploration for a new biofuel feedstock resulted in Cymbopogon flexuosus as an alternative energy source. Raw oil of Cymbopogon flexuosus was obtained through steam distillation process. Cymbopogon flexuosus biofuel was blended with diesel fuel in various proportions on volume basis, namely 10, 20, 30, 40, and 100 percent and its properties were assessed according to American Society for Testing and Materials standards. The considered test fuel was experimentally analysed in a single cylinder diesel engine at 1500 rpm for its performance, emission and combustion characteristics. Among various blends, Fuel blend of Cymbopogon flexuosus biofuel 20% + diesel 80% fuel profile stayed close to diesel fuel resulting in higher thermal efficiency and lower hydrocarbon, carbon monoxide, and smoke emission. However, oxides of nitrogen and carbon dioxide emission was marginally higher for the test fuel considered. Cylinder pressure and heat release rate curves were lower at full load condition as compared with diesel fuel. Against the grim background of fossil fuel depletion, Fuel blend of Cymbopogon flexuosus biofuel 20% + diesel 80% fuel acts as a promising alternative fuel and brings hope to the nation as well as the research world.

Thermal barrier coatings application in diesel engines

Science.gov (United States)

Fairbanks, J. W.

1995-01-01

Commercial use of thermal barrier coatings in diesel engines began in the mid 70's by Dr. Ingard Kvernes at the Central Institute for Industrial Research in Oslo, Norway. Dr. Kvernes attributed attack on diesel engine valves and piston crowns encountered in marine diesel engines in Norwegian ships as hot-corrosion attributed to a reduced quality of residual fuel. His solution was to coat these components to reduce metal temperature below the threshold of aggressive hot-corrosion and also provide protection. Roy Kamo introduced thermal barrier coatings in his 'Adiabatic Diesel Engine' in the late 70's. Kamo's concept was to eliminate the engine block water cooling system and reduce heat losses. Roy reported significant performance improvements in his thermally insulated engine at the SAE Congress in 1982. Kamo's work stimulates major programs with insulated engines, particularly in Europe. Most of the major diesel engine manufacturers conducted some level of test with insulated combustion chamber components. They initially ran into increased fuel consumption. The German engine consortium had Prof. Woschni of the Technical Institute in Munich. Woschni conducted testing with pistons with air gaps to provide the insulation effects. Woschni indicated the hot walls of the insulated engine created a major increase in heat transfer he refers to as 'convection vive.' Woschni's work was a major factor in the abrupt curtailment of insulated diesel engine work in continental Europe. Ricardo in the UK suggested that combustion should be reoptimized for the hot-wall effects of the insulated combustion chamber and showed under a narrow range of conditions fuel economy could be improved. The Department of Energy has supported thermal barrier coating development for diesel engine applications. In the Clean Diesel - 50 Percent Efficient (CD-50) engine for the year 2000, thermal barrier coatings will be used on piston crowns and possibly other components. The primary purpose of the

Utilization of Variable Consumption Biofuel in Diesel Engine

Science.gov (United States)

Markov, V. A.; Kamaltdinov, V. G.; Savastenko, A. A.

2018-01-01

The depletion of oil fields and the deteriorating environmental situation leads to the need for the search of new alternative sources of energy. Actuality of the article due to the need for greater use of the alternative fuels in internal combustion engines is necessary. The advantages of vegetables origin fuels using as engine fuels are shown. Diesel engine operation on mixtures of petroleum diesel and rapeseed oil is researched. A fuel delivery system of mixture biofuel with a control system of the fuel compound is considered. The results of the system experimental researches of fuel delivery of mixture biofuel are led.

Biodiesel de mamona no diesel interior e metropolitano em trator agrícola Mamona biodiesel in interior and metropolitan diesel in agricultural tractor

Directory of Open Access Journals (Sweden)

Rubens A. Tabile

2009-09-01

Full Text Available A demanda de recursos energéticos pelos sistemas de produção, aliada à escassez dos combustíveis fósseis, tem motivado a produção do Biodiesel, que é um combustível obtido de fontes renováveis. O objetivo deste trabalho foi realizar dois ensaios: o primeiro dinâmico, para avaliar o desempenho operacional utilizando como parâmetro o consumo de combustível, e o segundo, estático, para mensurar a opacidade da fumaça (material particulado do motor de um trator agrícola, operando com diesel metropolitano e interior misturados ao Biodiesel de mamona, em sete proporções. O trabalho foi conduzido no Departamento de Engenharia Rural da UNESP/Jaboticabal - SP. Os resultados mostraram que o tipo de diesel influenciou no consumo de combustível e na opacidade da fumaça, sendo o diesel metropolitano de melhor qualidade; observou-se, também, que à medida que a proporção de Biodiesel aumentou, o mesmo ocorreu para o consumo de combustível; entretanto, a opacidade da fumaça reduziu com o acréscimo de Biodiesel até B75.The demand for energy resources by production systems allied to scarcity of fossil fuels has driven the production of Biodiesel, a fuel produced from renewable sources. The purpose of this study was realize two tests, the first dynamics to assess the operational performance as a parameter of consumption of fuel, the second static to measure the smoke opacity (particulate material from an engine of a farm tractor, operating with interior and metropolitan diesel mixed with castor beans Biodiesel in seven proportions. The tests were conducted in the Rural Engineering Department of UNESP/Jaboticabal - SP. The results showed that the kind of diesel influenced the consumption of fuel and smoke opacity, and the metropolitan diesel showed better quality, it was observed as well that as biodiesel proportion increased, consumption of fuel increased too, however, the opacity of smoke decreased with an increase of Biodiesel by B75.

Influence of diesel engine combustion on the rupture strength of partially stabilized zirconia

International Nuclear Information System (INIS)

Brinkman, C.R.; Begun, G.M.; Cavin, O.B.; Foster, B.E.; Graves, R.L.; Kahl, W.K.; Liu, K.C.; Simpson, W.A.

1989-01-01

Results are reported for tests on partially stabilized zirconia (PSZ-TS and MS grade) bars exposed in the combustion chambers of two operating single-cylinder 0.825-L diesel engines. Specifics of test conditions and procedures are presented. Subsequent to exposure, the bars were subjected to four-point bending and the rupture strengths determined. The TS grade showed a decrease in average strength of 32%, while the strength of the MS grade decreased by about 9% in comparison to average behavior of unaged material. Results of X-ray diffraction analysis, Raman spectroscopy, isothermal aging studies, and ceramographic characterization are given to define reasons for material degradation

Simulation of diesel engine energy conversion processes

Directory of Open Access Journals (Sweden)

А. С. Афанасьев