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The objectives of the present work are to investigate the regulated and unregulated (particle) emissions of a classical and modern 2-stroke and a typical 4-stroke scooter with different ethanol blend fuels. There is also comparison of two different ethanol fuels: pure ethanol (E) *) and hydrous ethanol (EH) which contains 3.9% water and is denatured with 1.5% gasoline. Special attention is paid in this research to the hydrous ethanol, since the production costs of hydrous ethanol are much less than those for (dry) ethanol. The vehicles are with carburettor and without catalyst, which represents the most frequent technology in Eastern Asia and offers the information of engine-out emissions. Exhaust emissions measurements have been performed with fuels containing ethanol (E), or hydrous ethanol (EH) in the portion of 5, 10, 15 and 20% by volume. During the test systematical analysis of particle mass (PM) and nano-particles counts (NP) were carried out.

A gasoline Road Octane study was conducted by the Coordinating Research Council (CRC) to evaluate the effects of heavy aromatics (C9 and heavier) and ethanol content on Road Octane performance independent of Research Octane Number (RON) and Motor Octane Number (MON). Maximum-throttle and part-throttle Road ON’s were found to be well predicted by equations containing only RON and MON terms. Heavier aromatics were found to have a small adverse effect on both maximum-throttle and part-throttle Road ON independent of its direct effects on RON and MON. The all-car data did not show a significant ethanol-content effect, but eight of the thirty-seven cars did show significant effects for ethanol content.

Controlled Auto Ignition (CAI), also known as Homogeneous Charge Compression Ignition (HCCI), is one of the most promising combustion technologies to reduce the fuel consumption and NOx emissions. Currently, CAI combustion is constrained at part load operation conditions because of misfire at low load and knocking combustion at high load, and the lack of effective means to control the combustion process. Extending its operating range including high load boundary towards full load and low load boundary towards idle in order to allow the CAI engine to meet the demand of whole vehicle driving cycles, has become one of the key issues facing the industrialisation of CAI/HCCI technology. Furthermore, this combustion mode should be compatible with different fuels, and can switch back to conventional spark ignition operation when necessary. In this paper, the CAI operation is demonstrated on a 2-stroke gasoline direct injection (GDI) engine equipped with a poppet valve train.

The fuel injection in internal combustion engines plays a crucial role in the mixture formation, combustion process and pollutants' emission. Its correct modeling is fundamental to the prediction of an engine performance through a computational fluid dynamics simulation. In the first part of this work a tridimensional numerical simulation of a multi-hole’s injector, using ethanol as fuel, is presented. The numerical simulation results were compared to experimental data from a fuel spray injection bench test in a quiescent vessel. The break up model applied to the simulation was the combined Kelvin-Helmholtz Rayleigh-Taylor, and a sensitivity analysis of the liquid fuel penetration curve, as well on the overall spray shape was performed according to the model constants. Experimental spray images were used to aid the model tuning. The final configuration of the KH-RT model constants that showed best agreement with the measured spray was C3 equal to 0.5, B1, 7 and Cb, 0.

In July 1997, the Pacific Northwest and Alaska Regional Bioenergy Program, in cooperation with several industrial and institutional partners initiated a long-haul 322,000 km (200,000 mile) operational demonstration using a biodiesel and diesel fuel blend in a 324 kW (435 HP), Caterpillar 3406E Engine, and a Kenworth Class 8 heavy duty truck. This project was designed to: develop definitive biodiesel performance information, collect emissions data for both regulated and non-regulated compounds including mutagenic activity, and collect heavy-duty operational engine performance and durability information. To assess long-term engine durability and wear; including injector, valve and port deposit formations; the engine was dismantled for inspection and evaluation at the conclusion of the demonstration. The fuel used was a 50% blend of biodiesel produced from used cooking oil (hydrogenated soy ethyl ester) and 50% 2-D petroleum diesel.

The low auto-ignition temperature, rapid evaporation and high cetane number of dimethyl ether (DME) enables the use of low-pressure direct injection in compression ignition engines, thus potentially bringing the cost of the injection system down. This in turn holds the promise of bringing CI efficiency to even the smallest engines. A 50cc crankcase scavenged two-stroke CI engine was built based on moped parts. The major alterations were a new cylinder head and a 100 bar DI system using a GDI-type injector. Power is limited by carbon monoxide emission but smoke-free operation and NOx < 200ppm is achieved at all points of operation.

Life Cycle Analysis (LCA) considers the key environmental impacts for the entire life cycle of alternative products or processes in order to select the best alternative. An ideal LCA would be an expensive and time consuming process because any product or process typically involves many interacting systems and a considerable amount of data must be analysed for each system. Practical LCA methods approximate the results of an ideal analysis by setting limited analysis boundaries and by accepting some uncertainty in the data values for the systems considered. However, there is no consensus in the LCA field on the correct method of selecting boundaries or on the treatment of data set uncertainty. This paper demonstrates a new method of selecting system boundaries for LCA studies and presents a brief discussion on applying Monte Carlo Analysis to treat the uncertainty questions in LCA.

THE object of this paper is to emphasize some of the problems entering into the manufacture, control, and utilization of diesel fuel for mobile and high-speed diesel engines. The importance of ignition quality, as expressed by cetane number, is illustrated for rating the performance characteristics of a fuel. The relationship of cetane number to such engine characteristics as smoke, roughness, carbon deposits, starting, and exhaust odor, is given. The influence of the crude from which the diesel fuel is derived, and the influence of the method and degree of refining on the properties of the finished fuel, are brought out in an attempt to explain the cause for the variation in diesel fuels. The properties of straight-run and cracked fractions of gas oils from several crude sources are given, as well as the properties of several fuels obtained by blending these stocks.

The paper discusses the concept, specification and overall performance of a 10 kW electric power range extender suitable for electric plug-in and series hybrid vehicles, based on a single cylinder, high speed, four stroke internal combustion engine, tested and developed at Istituto Motori CNR of Italy. This unit has been conceived from the beginning as a compact on board recharging system for the mentioned kind of means, and especially for city cars and small commercial vehicles. The paper starts by defining some characteristics, advantages and drawbacks of an electric city car, followed by the criteria adopted to characterize the nominal power of the range extender. Then, the ratio which leaded to the adoption of a single cylinder internal combustion engine is discussed, followed by an explanation of the main design characteristics of the whole unit.

A multi-hole direct injection injector was studied by means of image analysis. Methodologies based on an automatic process of cone angle measurement and edge detection were applied for the spray images generated by a 100 bar injection pressure discharged into a pressurized rigid chamber. A criterion based on pixel values was taken to localize the spray edges as angular coordinates and also with x and y position data. The high pixel values were associated with liquid phase while the low pixel values were associated to its absence. Computational codes written in MATLAB environment were used to analyze the numerical matrices associated to the images. Using the written MATLAB codes, a comparison of the effect of atmospheric back pressure, inside the chamber, on the spray pattern, cone angle and spray penetration were evaluated. The chamber was pressurized with 2.5, 5.0, 7.5 and 10 bar of back pressure. The tested fluid injected was EXXSOL D60 for simulating ethanol fuel behavior.

This paper presents the findings of a study that compared the fuel efficiency, power, emissions, engine wear and material compatability characteristics of automotive four-stroke cycle engines fueled by E95 (95 % ethyl alcohol and 5% lead free regular gasoline) and 87 pump octane number lead-free gasoline. A group of six senior Automotive Engineering Technology students, conducted the research over a one-year period. Two Mankato State University faculty served as directors for the project. The laboratory facilities at Mankato State University were used for vehicle modification and testing. Two identically equipped 1994 Geo Metros with 1.0 liter, three cylinder, throttle body fuel injected engines were used for this study. After a 6440 km (4000 mile) break-in period, to assure the cars performance characteristics were equal, one of the vehicles was converted to run on E95.

This study aims to clarify the spray development of ethanol, gasoline and iso-octane fuel, delivered by a multi-hole injector and spark-ignition direct-injection (SIDI) fuelling system. The focus is on how fuel properties impact temporal and spatial evolution of sprays at realistic ambient conditions. Two optical facilities were used: (1) a constant-flow spray chamber simulating cold-start conditions and (2) a single-cylinder SIDI engine running at normal, warmed-up operating conditions. In these optical facilities, high-speed Mie-scattering imaging is performed to measure penetrations of spray plumes at various injection pressures of 4, 7, 11 and 15 MPa. The results show that the effect of fuel type on the tip penetration length of the sprays depends on the injection conditions and the level of fuel jet atomisation and droplet breakup.

The use of ethyl alcohol as a motor fuel blending agent has been promoted as method for reducing the consumption of petroleum. A mixture of 90 volume percent unleaded regular gasoline and 10 volume percent anhydrous ethyl alcohol, popularly known as “Gasohol,” has probably received the most current interest. This report is a summary and analysis of all currently available comparative Gasohol fuel consumption data. Usable data were eventually obtained from sixteen (16) different Gasohol test programs conducted by various public and private organizations. Ten (10) of these programs were conducted with chassis dynamometers, and the remaining six (6) were road tests of varying duration. Data from each or the test programs were subjected to a statistical analysis to determine whether the results were significant. Finally, all of the data were combined in order to determine an overall mean Gasohol fuel economy effect.

A single cylinder indirect injection diesel engine was used to evaluate the emissions, fuel consumption, and ignition delay of non-petroleum liquid fuels derived from coal, shale, and tar sands. Correlations were made relating fuel properties with exhaust emissions, fuel consumption, and ignition delay. The results of the correlation study showed that the indicated fuel consumption, ignition delay, and CO emissions significantly correlated with the H/C ratio, specific gravity, heat of combustion, aromatics and saturates content, and cetane number, Multiple fuel properties were necessary to correlate the hydrocarbon emissions. The NOx emissions did not correlate well with any fuel property. Because these fuels from various resources were able to correlate succesfully with many of the fuel properties suggests that the degree of refinement or the chemical composition of the fuel is a better predictor of its performance than its resource.

An experimental study has been conducted to investigate the effects of indolene-ethanol blends on engine performance during homogeneous charge compression ignition (HCCI) operation of single-cylinder engine. The engine performance and HCCI stability were investigated and the high enthalpy of vaporization of ethanol resulted in significant intake charge cooling and limited the stable HCCI operation to higher intake temperatures. In the second part of the study, intake air preheat temperature was used to compensate for some of the thermal effects introduced by the fuel blends. The effects of equivalence ratio at a same end of compression temperature for different fuel blends showed that increasing the ethanol content of the fuel blend can extend the stable HCCI lean operating limit. Engine performance was characterized by in-cylinder pressure data, heat release rate, indicated mean effective pressure and exhaust gas emissions (NO and HC).

Different methods to improve the performance of a WCO (waste cooking oil of sunflower) based mono cylinder compression ignition (CI) engine were investigated. Initially WCO was converted into its emulsion by emulsification process and tested as fuel. In the second phase, the engine intake system was modified to admit excess oxygen along with air to test the engine with WCO and WCO emulsion as fuels under oxygen enriched environment. In the third phase, the engine was modified to work in the dual fuel mode with hydrogen being used as the inducted fuel and either WCO or WCO emulsion used as the pilot fuel. All the tests were carried out at 100% and 40% of the maximum load (3.7 kW power output) at the rated speed of 1500 rpm. Engine data with neat diesel and neat WCO were used for comparison. WCO emulsion indicated considerable improvement in performance. The smoke and NOx values were noted to be less than neat WCO.

Ethanol fuel has received renewed attention in recent years because of its oxygenate content and its potential to reduce greenhouse gas emissions from spark ignition engines. The economic impact on farm industry has been one of the drivers for its use in engines in the U.S. Although ethanol, in various blends, has been used in automotive engines for almost a decade the fuel has seldom been utilized in off-highway engines where the fuel systems are not well controlled. This investigation was conducted to evaluate exhaust emissions and combustion characteristics of E85 fuel in an off-highway engine used in farm equipment. A single-cylinder, four-stroke, spark ignition engine equipped with a carburetor was used to investigate combustion and exhaust emissions produced by gasoline and blends of gasoline and ethanol fuels. The engine fuel system was modified to handle flow rates required by the engine. A variable size-metering orifice was used to control air-to-fuel ratios.

Two oxygenated fuels were evaluated on a single-cylinder diesel engine and compared to three hydrocarbon diesel fuels. The oxygenated fuels included canola biodiesel (canola methyl esters, CME) and CME blended with dibutyl succinate (DBS), both of which are or have the potential to be bio-derived. DBS was added to improve the cold flow properties, but also reduced the cetane number and net heating value of the resulting blend. A 60-40 blend of the two (60% vol CME and 40% vol DBS) provided desirable cold flow benefits while staying above the U.S. minimum cetane number requirement. Contrary to prior vehicle test results and numerous literature reports, single-cylinder engine testing of both CME and the 60-40 blend showed no statistically discernable change in NOx emissions relative to diesel fuel, but only when constant intake oxygen was maintained.

Water injection is an effective method for knock control in spark-ignition engines. However, the requirement of a separate water source and the cost and complexity associated with a fully integrated system creates a limitation of this method to be used in volume production engines. The engine exhaust typically contains 10-15% water vapor by volume which could be condensed and potentially stored for future use. In this study, the exhaust condensate composition was assessed for its use as an effective replacement for distilled water. Specifically, condensate samples were collected pre and post-three-way catalyst (TWC) and analyzed for acidity and composition. The composition of the pre and post-TWC condensates was found to be similar however, the pre-TWC condensate was mildly acidic. The mild acidity has the potential to corrode certain components in the intake air circuit.

In many developing countries around the world, the plan of producing sufficient biodiesel (EN 14214) to meet the mandate of 20% blending with the diesel fuel (EN 590) was unachievable particularly due to two main reasons - the unavailability of sufficient feedstock and lack of high yielding drought tolerant plant based feed-stocks. Also, the production of biodiesel from these plant based bio-degradable source such as vegetable oil competes with the farm land utilization meant for growing food crops. Hence, the development of algae based technologies for a sustainable yield of biodiesel is gaining widespread importance. Industrial waste water effluent and sewage sludge water provides the best source of nutrients for the cultivation of microalgae. It is an indisputable fact that the recoverable oil yield from this unicellular organism is higher than that of any other food crop.