COMBUSTION AND EMISSIONS CHARACTERISTICS OF A COMPRESSION IGNITION ENGINE FUELLED WITH N-BUTANOL BLENDS

2015 ◽  
Vol 77 (8) ◽  
Author(s):  
I. M. Yusri ◽  
M. K. Akasyah ◽  
R. Mamat ◽  
O. M. Ali

The use of biomass based renewable fuel, n-butanol blends for compression ignition (CI) engine has attracted wide attention due to its superior properties such as better miscibility, higher energy content, and cetane number as compared to other alternatives fuel. In this present study the use of n-butanol 10% blends (Bu10) with diesel fuel has been tested using multi-cylinder, 4-stroke engine with common rail direct injection system to investigate the combustion and emissions of the blended fuels. Based on the tested engine at BMEP=3.5Bar. Based on the results Bu10 fuel indicates lower first and second peak pressure by 5.4% and 2.4% for engine speed 1000rpm and 4.4% and 2.1% for engine speed 2500rpm compared to diesel fuel respectively. Percentage reduction relative to diesel fuel at engine speeds 1000rpm and 2500rpm for Bu10: Exhaust temperature was 7.5% and 5.2% respectively; Nitrogen oxides (NOx) 73.4% and 11.3% respectively.

2014 ◽  
Vol 663 ◽  
pp. 26-33
Author(s):  
Y.H. Teoh ◽  
H.H. Masjuki ◽  
M.A. Kalam ◽  
Muhammad Afifi Amalina ◽  
H.G. How

This study investigated the effects of premixed diesel fuel on the auto-ignition characteristics in a light duty compression ignition engine. A partial homogeneous chargecompression ignition (HCCI) engine was modified from a single cylinder, four-stroke, direct injection compression ignition engine. The partial HCCI is achieved by injecting diesel fuel into the intake port of the engine, while maintaining diesel fuel injected in cylinder for combustion triggering. The auto-ignition of diesel fuel has been studied at various premixed ratios from 0 to 0.60, under engine speed of 1600 rpm and 20Nm load. The results for performance, emissions and combustion were compared with those achieved without premixed fuel. From the heat release rate (HRR) profile which was calculated from in-cylinder pressure, it is clearly observed that two-stage and three-stage ignition were occurred in some of the cases. Besides, the increases of premixed ratio to some extent have significantly reduced in NO emission.


2005 ◽  
Vol 6 (3) ◽  
pp. 215-230 ◽  
Author(s):  
Y Ra ◽  
E J Hruby ◽  
R D Reitz

Homogeneous charge compression ignition (HCCI) combustion is an alternative to current engine combustion systems and is used as a method to reduce emissions. It has the potential nearly to eliminate engine-out NOx emissions while producing diesel-like engine efficiencies, when a premixture of gas-phase fuel and air is burned spontaneously and entirely by an autoignition process. However, when direct injection is used for diesel fuel mixture preparation in engines, the complex in-cylinder flow field and limited mixing times may result in inhomogeneity of the charge. Thus, in order to minimize non-uniformity of the charge, early injection of the fuel is desirable. However, when fuel is injected during the intake or early compression stroke, the use of high-pressure injection is limited by the relatively low in-cylinder gas pressure because of spray impingement on the cylinder walls. Thus, it is also of interest to consider low-pressure injectors as an alternative. In the present paper, the parametric behaviour of the combustion characteristics in an HCCI engine operated with a low-pressure fuel injector were investigated through numerical simulations and engine experiments. Parameters including the start-of-injection (SOI) timing and exhaust gas recirculation were considered, and diesel and n-heptane fuels were used. The results show good agreement of behaviour trends between the experiments and the numerical simulations. With its lower vaporization rates, significant effects of the SOI timing and intake gas temperature were seen for diesel fuel due to the formation of wall films. The modelling results also explained the origin of high-temperature NO x-producing regions due to the effect of the gas density on the spray.


Author(s):  
Jakub Čedík ◽  
Martin Pexa ◽  
Bohuslav Peterka ◽  
Miroslav Müller ◽  
Michal Holubek ◽  
...  

Liquid biofuels for compression ignition engines are often based on vegetable oils. In order to be used in compression ignition engine the vegetable oils have to be processed because of their high viscosity or it is also possible to use vegetable oils in fuel blends. In order to decrease the viscosity of the fuel blends containing crude vegetable oil the alcohol-based fuel admixtures can be used. The paper describes the effect of rapeseed oil–diesel fuel–n-butanol blends on combustion characteristics and solid particles production of turbocharged compression ignition engine. The 10% and 20% concentrations of n-butanol in the fuel blend were measured and analysed. The engine Zetor 1204, located in tractor Zetor Forterra 8641 with the power of 60kW and direct injection was used for the measurement. The engine was loaded through power take off shaft of the tractor using mobile dynamometer MAHA ZW500. The measurement was carried out in stabilized conditions at 20%, 60% and 100% engine load. The engine speed was kept at 1950 rpm. Tested fuel blends showed lower production of solid particles than diesel fuel and lower peak cylinder pressure and with increasing concentration of n-butanol in the fuel blend the ignition delay was prolonged and premixed phase of combustion was increased.


Energies ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2398 ◽  
Author(s):  
Alfredas Rimkus ◽  
Jonas Matijošius ◽  
Sai Manoj Rayapureddy

This article presents the results of a study of energy and ecological indicators at different engine loads (BMEP) adjusting the Start of Injection (SOI) of a Compression Ignition Engine fuelled with blends of diesel (D), rapeseed methyl ester (RME)-based biodiesel and isopropanol (P). Fuel blends mixed at D50RME45P5, D50RME40P10 and D50RME30P20 proportions were used. Alcohol-based fuels, such as isopropanol, were chosen because they can be made from different biomass-based feedstocks and used as additives with diesel fuel in diesel engines. Diesel fuel and its blend with 10% alcohol have almost the same thermal efficiency (BTE). In further examination of energy and ecological indicators, combustion parameters were analysed at SOI 6 CAD BTDC using AVL BOOST software (BURN subprogram). Increasing alcohol content in fuel blends led to a reduced cetane number, which prolonged the ignition delay phase and intensified heat release in the premixed combustion phase. Higher combustion temperatures and oxygen content in the fuel blends increased NOx emissions. Lower C/H ratios and higher O2 levels affected by RME and isopropanol reduced smoke emissions.


Author(s):  
Myung Yoon Kim ◽  
Seung Hyun Yoon ◽  
Jin Woo Hwang ◽  
Chang Sik Lee

An experimental investigation was performed on the effect of engine speed, exhaust gas recirculation (EGR), and boosting intake pressure on the particulate size distribution and exhaust gas emissions in a compression ignition engine fueled with biodiesel derived from soybean. The results obtained by biodiesel fuel were compared to those obtained by petroleum diesel fuel with a sulfur content of 16.3ppm. A scanning mobility particulate sizer was used for size distribution analysis, and it measured mobility equivalent particulate diameter in the range of 10.4–392.4nm. In addition to the size distribution of the particulates, exhaust emissions, such as oxides of nitrogen (NOx), hydrocarbon, and carbon monoxide emissions, and combustion characteristics under different engine operating parameters were investigated. The engine operating parameters in terms of engine speed, EGR, and intake pressure were varied to investigate their individual impacts on the combustion and exhaust emission characteristics. As the engine speed was increased for both fuels, the larger size particulates, which dominantly contribute particulate mass, were increased; however, total numbers of particulate were reduced. Compared to diesel fuel, the combustion of biodiesel fuel reduced particulate concentration of relatively larger size where most of the particulate mass is found. Moreover, dramatically lower hydrocarbon and carbon monoxide emissions were found in the biodiesel-fueled engine. However, the NOx emission of the biodiesel-fueled diesel engine shows slightly higher concentration compared to diesel fuel at the same injection timing. EGR significantly increased the larger size particulates, which have diameter near the maximum measurable range of the instrument; however, the total number of particulates was found not to significantly increase with increasing EGR rate for both fuels. Boosting intake pressure shifted the particulate size distribution to smaller particulate diameter and effective reduction of larger size particulate was found for richer operating conditions.


Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 310
Author(s):  
Qiwei Wang ◽  
Rong Huang ◽  
Jimin Ni ◽  
Qinqing Chen

n-Octanol, as an oxygenated fuel, is considered as one of the most promising alternative fuels, owing to advantages such as its low hygroscopic nature, high cetane number, and high energy content. However, the introduction of n-octanol leads to a higher viscosity and latent heat of evaporation (LHOE), affecting the combustion and emission performances of compression ignition (CI) engines. This study sheds light on the effect of injection pressures (IPs, ranging from 60 to 160 MPa) on the combustion and emission performances of a turbocharged CI engine, in conjunction with n-octanol/diesel blends. According to the proportion of oxygen content, the test fuels contain pure diesel (N0), N2.5 (2.5% oxygen content in the blending fuels), and N5 (5% oxygen content in the blending fuels). The results indicate that the blending fuels have little influence on the in-cylinder pressure, ignition delay (ID), and CA50, but they improve the brake thermal efficiency (BTE). In terms of emissions, with the use of blending fuels, the levels of carbon monoxide (CO), soot, and nitrogen oxides (NOX) decrease, whereas emissions of hydrocarbons (HC) slightly increase. With increasing IP, the ID, brake specific fuel consumption (BSFC), HC, CO, and soot decrease significantly, and the BTE and NOX increase. In addition, the combination of n-octanol and IP improves the trade-off between NOX and soot and reduces the CO emissions.


2010 ◽  
Vol 7 (1) ◽  
pp. 229-234 ◽  
Author(s):  
M. P. Sudeshkumar ◽  
G. Devaradjane

Rapid depletion of petroleum reserves and the environmental pollution caused by the growing use of conventional fuels created a challenge before the world that new type of fuels should replace the conventional fuels to achieve the future emission regulations. Hence great deal of research effort has been focused to find alternative fuel. The consideration of oxygenates with diesel fuel is a recent approach receives great attention in reducing the exhaust emissions of an engine The combustion, performance and emission characteristics of diesel fuel and oxygenated blends with diesel are analyzed in a four stroke naturally aspirated single cylinder direct injection compression ignition engine. The additives include 2-Ethoxyethanol (2EE), DiethyleneGlycol Dimethyl ether (DGM) and 2-Methoxyethanol (2ME) and the oxygenated compounds were selected based on the availability, price and oxygen content. These oxygenated compounds are blended with diesel fuel in proportion of 6% by volume. Combustion parameters such as in-cylinder pressure and Heat release rate were studied. The engine emission characteristics of the Compression ignition (CI) engine fuelling with oxygenated blends are studied experimentally. The performance of oxygenates on thermal efficiency and specific fuel consumption were studied. Comparing the combustion, performance and emission, the addition of 2-methoxy ethanol blend shows better performance than other two oxygenated blends with diesel and diesel fuel.


2005 ◽  
Vol 128 (3) ◽  
pp. 497-505 ◽  
Author(s):  
Dae Sik Kim ◽  
Myung Yoon Kim ◽  
Chang Sik Lee

In order to obtain the reduction effect of NOx and soot emission in a partial homogeneous charge compression ignition engine, premixed fuel was supplied with direct injection diesel fuel. Several additional systems such as a premixed fuel injection system, exhaust gas recirculation (EGR) system, supercharger, and air heating system were equipped in the intake manifold of conventional diesel engine. Premixed fuel with air was compressed and ignited by the directly injected diesel fuel in the combustion chamber at the end of compression stroke. The effect of premixed fuel on combustion and emission characteristics of HCCI diesel engine was investigated experimentally under various conditions of intake air temperature, pressure, and EGR rate. The results showed that in case of the use of gasoline as a premixed fuel, single stage ignition is found, but premixing the diesel fuel accompanies the cool flame prior to the combustion of the directly injected diesel fuel. For the gasoline premixed fuel, both NOx and soot can be reduced by the increase of premixed ratio simultaneously. However, for the diesel premixed fuel, the increase of premixed ratio does not have a significant effect in reducing the soot emission.


2020 ◽  
Vol 14 (3) ◽  
pp. 151
Author(s):  
Mohammed Kadhim Allawi ◽  
Mohanad Kadhim Mejbel ◽  
Younis Muhsin Younis ◽  
Sabah Jameel Mezher

Author(s):  
Anita I. Ramírez ◽  
Sibendu Som ◽  
Lisa A. LaRocco ◽  
Timothy P. Rutter ◽  
Douglas E. Longman

There has been an extensive worldwide search for alternate fuels that fit with the existing infrastructure and would thus displace fossil-based resources. In metabolic engineering work at Argonne National Laboratory, strains of fuel have been designed that can be produced in large quantities by photosynthetic bacteria, eventually producing a heavy alcohol called phytol (C20H40O). Phytol’s physical and chemical properties (cetane number, heat of combustion, heat of vaporization, density, surface tension, vapor pressure, etc.) correspond in magnitude to those of diesel fuel, suggesting that phytol might be a good blending agent in compression ignition (CI) engine applications. The main reason for this study was to investigate the feasibility of using phytol as a blending agent with diesel; this was done by comparing the performance and emission characteristics of different blends of phytol (5%, 10%, 20% by volume) with diesel. The experimental research was performed on a single-cylinder engine under conventional operating conditions. Since phytol’s viscosity is much higher than that of diesel, higher-injection-pressure cases were investigated to ensure the delivery of fuel into the combustion chamber was sufficient. The influence of the fuel’s chemical composition on performance and emission characteristics was captured by doing an injection timing sweep. Combustion characteristics as shown in the cylinder pressure trace were comparable for the diesel and all the blends of phytol at each of the injection timings. The 5% and 10% blends show lower CO and similar NOx values. However, the 20% blend shows higher NOx and CO emissions, indicating that the chemical and physical properties have been altered substantially at this higher percentage. The combustion event was depicted by performing high-speed natural luminosity imaging using endoscopy. This revealed that the higher in-cylinder temperatures for the 20% blend are the cause for its higher NOx emissions. In addition, three-dimensional simulations of transient, turbulent nozzle flow were performed to compare the injection and cavitation characteristics of phytol and its blends. Specifically, area and discharge coefficients and mass flow rates of diesel and phytol blends were compared under corresponding engine operating conditions. The conclusion is that phytol may be a suitable blending agent with diesel fuel for CI applications.


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