Search Results

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 direct injection system in which fuel was injected through the cylinder wall was developed and detailed investigation was made for the purpose of reducing short-circuit of fuel in 2-stroke engines. As a result of dynamo tests using 430cc single cylinder engine, it was found that the injector was best attached at a location as close to TDC as possible on the rear transfer port side, and that the entire amount of fuel should be injected towards the piston top surface. Emissions were worsened if fuel was injected towards the exhaust port or spark plug. Although the higher injection pressure resulted in large emissions reduction effects, it did not have a significant effect on fuel consumption. When a butterfly exhaust valve, known to be effective against irregular combustion in the light load range, was applied, it was found to lead to further reductions in HC emission and fuel consumption while also improving combustion stability.

The road transportation sector is undergoing significant changes, and new green scenarios for sustainable mobility are being proposed. In this context, a diversification of the vehicles’ propulsion, based on electric powertrains and/or alternative fuels and technological improvements of the electric vehicles charging stations, are necessary to reduce greenhouse gas emissions. The adoption of internal combustion engines operating with alternative fuels, like methanol, may represent a viable solution for overcoming the limitations of actual grid connected charging infrastructure, giving the possibility to realize off-grid charging stations. This work aims, therefore, at investigating this last aspect, by evaluating the performance of an internal combustion engine fueled with methanol for stationary applications, in order to fulfill the potential demand of an on off-grid charging station.

Advanced Vehicle Technologies (AVT), a Ballarat Australia based company, has developed the World's first diesel to 100% LPG conversion for heavy haul trucks. There is no diesel required or utilized on the trucks. The engine is converted with minimal changes into a spark ignition engine with equivalent power and torque of the diesel. The patented technology is now deployed in 2 Mercedes Actros trucks. The power output in engine dynamometer testing exceeds that of the diesel (in excess of 370 kW power and 2700 Nm torque). In on-road application the power curve is matched to the diesel specifications to avoid potential downstream power-train stress. Testing at the Department of Transport Energy & Infrastructure, Regency Park, SA have shown the Euro 3 truck converted to LPG is between Euro 4 and Euro 5 NOx levels, CO2 levels 10% better than diesel on DT80 test and about even with diesel on CUEDC tests.

Two Cummins B5.9L engines were fueled with 100% biodiesel in excess of 48 months by the Agricultural Engineering Department at the University of Missouri-Columbia. The engines used to power Dodge pickups. The engine lubricating oil was sampled at 1000 mile intervals for analysis. Statistical analysis of the engine lubricating oil indicated that the wear metal levels in the lubricating oil were normal. A reduction in power was noted when the engines were tested using a chassis dynamometer. The 1991 pickup has been driven 110,451 km and the 1992 pickup has been driven approximately 177,022 km. The pickups averaged 6.9 km/L. Engine fuel efficiency and material compatibility issues are addressed in the paper.

Nine identical 40-ft. transit buses were operated on B20 and diesel for a period of two years - five of the buses operated exclusively on B20 (20% biodiesel blend) and the other four on petroleum diesel. The buses were model year 2000 Orion V equipped with Cummins ISM engines, and all operated on the same bus route. Each bus accumulated about 100,000 miles over the course of the study. B20 buses were compared to the petroleum diesel buses in terms of fuel economy, vehicle maintenance cost, road calls, and emissions. There was no difference between the on-road average fuel economy of the two groups (4.41 mpg) based on the in-use data, however laboratory testing revealed a nearly 2% reduction in fuel economy for the B20 vehicles. Engine and fuel system related maintenance costs were nearly identical for the two groups until the final month of the study.

A prototype 2007 ISL Cummins diesel engine equipped with a diesel oxidation catalyst (DOC), diesel particle filter (DPF), variable geometry turbocharger (VGT), and cooled exhaust gas recirculation (EGR) was tested at Southwest Research Institute (SwRI) under a high-load accelerated durability cycle for 1000 hours with B20 soy-based biodiesel blends and ultra-low sulfur diesel (ULSD) fuel to determine the impact of B20 on engine durability, performance, emissions, and fuel consumption. At the completion of the 1000-hour test, a thorough engine teardown evaluation of the overhead, power transfer, cylinder, cooling, lube, air handling, gaskets, aftertreatment, and fuel system parts was performed. The engine operated successfully with no biodiesel-related failures. Results indicate that engine performance was essentially the same when tested at 125 and 1000 hours of accumulated durability operation.

Engines and fuels for transport as well as off-road applications are facing a double challenge: bring local pollution to the level requested by the most stringent city air quality standard reduce CO2 emission in order to minimize the global warming risk. These goals stimulate new developments both of conventional and alternative engines and fuels technologies. New combustion processes known as Controlled Auto-Ignition (CAI™) for gasoline engine and Homogeneous Charge Compression Ignition (HCCI) for Diesel engine are the subject of extensive research world wide and particularly at IFP for various applications such as passenger cars, heavy-duty trucks and buses as well as small engines. Because of the thermo-chemistry of the charge, the thermal NOx formation and the soot production are in principle much lower than in flames typical of conventional engines.

A mobile and dispersed power system is necessary for an advanced technological-industrial society. Today's petroleum-based system discharges waste products and heat and is growing exponentially. Energy resource commitment has already intersected “ultimate” low-cost petroleum supplies in the United States and will do so for the world before 2000; this portends major changes and cost increases. The twenty-first century system for mobile-dispersed power will reflect the energy source selected to replace petroleum-for example, coal, solar insolation, or uranium. It will incorporate a fuel intermediate such as methanol, ammonia, or hydrogen, and a suitably matched “engine.” The complete change will require more than 25 years because of the magnitude, fragmentation, structural gaps, complexity, and variety of the mobile-dispersed power system.

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.

The Injection Rate Shaping consists in a novel injection strategy to control air-fuel mixing quality via a suitable variation of injection timing that affects the injection rate profile. This strategy has already provided to be useful to increase combustion efficiency and reduce pollutant emissions in the modern compression ignition engines fed with fossil Diesel fuel. But nowadays, the ever more rigorous emission targets are enhancing a search for alternative fuels and/or new blends to replace conventional ones, leading, in turn, a change in the air-fuel mixture formation. In this work, a 1D model of spray injection aims to investigate the combined effects of both Injection Rate Shaping and alternative fuels on the air-fuel mixture formation in a compression ignition engine. In a first step, a ready-made model for conventional injection strategies has been set up for the Injection Rate Shaping.

Methanol fuel was tested in a prototype 2-cycle ceramic heat insulated engine with a swirl chamber. It was found that the 2-cycle ceramic heat insulated engine with a compression ratio of 18:1 could ignite methanol without an auxiliary ignition system and emissions were substantially reduced in the whole load range.

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.

Due to the general requirements in the automotive industry to reduce the power consumption, fuel consumption rate and CO2 emission a new HID (High Intensity Discharge) bulb with only 25W is under development for front lighting systems. A first headlamp integrated in a hybrid vehicle is now launched as a first application in the market. The current regulation in ECE allows to get rid of the mandatory headlamp cleaning system and the automatic leveling requirement once the 25W HID bulb is applied. The reason for this is the objective luminous flux of the 25W HID bulb, which emits less than 2000 lm, a boundary defined in the regulation, where a headlamp cleaning and an automatic leveling is requested. That simplifies especially the integration in smaller vehicles and electric and hybrid vehicles. The paper describes the special design of the headlamp, the projector unit, the light performance, packaging advantages and future outlook of further applications in the near future.

An investigation of the possibility to extend the 3-dimensional modeling capabilities from conventional diesel to the HCCI combustion mode simulation was carried out. Experimental data was taken from a single cylinder engine operating with early injections for the HCCI and a split-injection (early pilot+main) for the high speed Diesel engine operation. To properly phase the HCCI mode in the experiments, high amounts of cooled EGR and a decreased compression ratio were used. In numerical simulation performed using KIVA3-V code, modified to incorporate the Detailed Chemistry Approach the same conditions were reproduced. Special attention is paid on the analysis of the events leading up to the auto-ignition, which was reasonably well predicted.

In the research of DME compression ignition engine, there are a lot of reports on the high fuel pressure systems which are used in the common-rail fuel injector and others for the DME mixture formation promotion. However, the initial development-cost of these fuel supply systems will be increased for small compression ignition engines. On the other hand, it has been understood that excellent thermal efficiency of DME compression ignition engine was obtained at the appropriate fuel injection timing by using the electronic controlled injector with low pressure injection. In this paper, the stabilization of combustion on DME compression ignition engine with low pressure injection was investigated for the influence of the fuel pressure and the combustion assistance with homogeneous charge.

A compound-laser welding method has been developed for the rapid three-dimensional welding of motorcycle aluminum-alloy structural parts. The term “compound-laser welding” means a high-speed welding method in which a number of lasers with different characteristics are arranged on the same axis. This paper reports the results of welding by a compound laser consisting of a YAG laser and a CO2 laser. It was found that compound-laser welding with two or more types of gases mixed as shielding gas gives a better welding performance than single-laser welding due to the advantages of the different lasers used in compound-laser welding.

A detailed reaction mechanism for the combustion of biodiesel fuels has recently been developed by Westbrook and co-workers. This detailed mechanism involves 5037 species and 19990 reactions, which prohibits its direct use in computational fluid dynamic (CFD) applications. In the present work, various mechanism reduction methods included in the Reaction Workbench software were used to derive a semi-detailed biodiesel combustion mechanism, while maintaining the accuracy of the master mechanism for a desired set of engine conditions. The reduced combustion mechanism for a five-component biodiesel fuel was employed in the FORTÉ CFD simulation package to take advantage of advanced chemistry solver methodologies and advanced spray models. Simulations were performed for a Volvo D12C heavy diesel engine fueled by RME fuel using a 72° sector mesh. Predictions were validated against measured in-cylinder parameters and exhaust emission concentrations.

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.

Recently the analysis of air-fuel mixing and combustion has become important under the stringent emissions regulations of diesel engines. In the case of gasoline engines, the KIVA computer program has been developed and used for the analysis of combustion. In this paper, the calculations of combustion phenomena in DI diesel engines are performed by modifying the KIVA program so as to be applicable to multi-hole nozzles and arbitrary patterns of injection rate. The thermophysical and ther-mochemical properties of gasoline are altered to those diesel fuel. In order to investigate the ability of this modified program, the calculations are compared with the experiments on single cylinder engines concerning the pressure, flame temperature and mass change of chemical species in cylinders. Furthermore, the calculation for the heavy duty DI diesel engine is performed with this diesel combustion program.