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Current flexi fuel gasoline and ethanol engines have efficiencies generally lower than dedicated gasoline engines. Considering ethanol has a few advantages with reference to gasoline, namely the higher octane number and the larger heat of vaporization, the paper explores the potentials of dedicated pure ethanol engines using the most advanced techniques available for gasoline engines, specifically direct injection, turbo charging and variable valve actuation. Computations are performed with state-of-the-art, well validated, engine and vehicle performance simulations packages, generally accepted to produce accurate results targeting major trends in engine developments. The higher compression ratio and the higher boost permitted by ethanol allows larger top brake efficiencies than gasoline, while variable valve actuation produces small penalties in efficiency changing the load.

Life Cycle Analysis (LCA) of alternative transportation fuels clearly shows the advantages of reducing the use of non renewable fossil fuels vs. renewable synthetic and biologic novel fuels to reduce the emissions of carbon dioxide. Being based on the natural or synthetic recycle of carbon dioxide through the use of renewable energy sources, use of these renewable fuels do not imply depletion of natural resources and is therefore sustainable in the long term. Renewable fuels and advanced internal combustion engines and power-trains are the technologies that in addition to be the most likely to produce benefits in term of carbon balance and fossil fuel saving, are also those that unequivocally have the smallest ecological footprint considering all the environmental implication of transportation technologies. All the other more exotic solutions having much higher environmental costs to produce, use and dispose of alternative transportation technologies.

The paper presents a novel design of a variable compression ratio advanced spark ignition engine that also permits an expansion ratio that may differ from the compression ratio therefore generating an Atkinson cycle effect. The stroke ratio and the ratio of maximum to minimum in-cylinder volumes may change with load and speed to provide the best fuel conversion efficiency. The variable ratio of maximum to minimum in-cylinder volumes also improves the full load power output of the engine. Brake specific fuel consumption maps are computed for a gasoline engine 2 Litres, in-line four, turbocharged and direct injection showings significant fuel savings during light and medium loads operation as well as improvement of full load output and fuel efficiency.

This paper explores through engine simulations the use of LPG and CNG gas fuels in a 1.5 liter Spark Ignition (SI) four cylinder gasoline engine with double over head camshafts, four valves per cylinder equipped with a novel mixture preparation and ignition system comprising centrally located Direct Injection (DI) injector and Jet Ignition (JI) nozzles. With DI technology, the fuel may be introduced within the cylinder after completion of the valve events. DI of fuel reduces the embedded air displacement effects of gaseous fuels and lowers the charge temperature. DI also allows lean stratified bulk combustion with enhanced rate of combustion and reduced heat transfer to the cylinder walls creating a bulk lean stratified mixture.

The paper presents design data and indicated, brake and mean effective pressure results for two successful racing engines developed by FIAT Auto Corse for touring car applications, namely the 690 2.5 liters V6 engine powering the Alfa Romeo 155 car developed for the 1996 International Touring Car (ITC) Championship and the 420 2.0 liters in-line 4 engine powering the Alfa Romeo 156 car developed for the 1998 Campionato Italiano Superturismo. In their first year of life, the sophisticated 690 engine was delivering 500 HP with a revolution limiter of 12000 rpm, while the more conservative 420 engine was delivering 310 HP with a revolution limiter of 8500 rpm. Brake mean effective pressures of these naturally aspirated engines were very close to the maximum achievable values for the racing engine technology of the late nineties, and certainly still a good reference point for development of new racing engines.

Favorable and unfavorable properties of hydrogen as a combustion engine fuel have been accommodated in a design of a fuel efficient and clean engine providing similar to gasoline maximum torque and power. The advanced H2ICE being developed is a turbocharged engine fitted with cryogenic port hydrogen fuel injection and the hydrogen assisted jet ignition (HAJI). The combustion chamber is designed to produce a high compression ratio and therefore high thermal efficiency. A waste gated turbocharger provides pressure boosting for an increased power density running ultra lean for SULEV operation without after treatment. Thanks to the combustion properties of hydrogen further enhanced by the HAJI system, the engine load is mainly controlled throttle-less decreasing the fuel-to-air equivalence ratio from ultra lean ϕ=0.43 to ultra-ultra lean ϕ=0.18. The computational model developed for addressing the major design issues and the predicted engine performance and efficiency maps are included.

The Bishop Rotary Valve (BRV) has the opportunity for greater breathing capacity than conventional poppet valve engines. However the combustion chamber shape is different from conventional engine with no opportunity for a central spark plug. This paper reports the development of a combustion analysis and design model using KIVA-3V code to locate the ignition centers and to perform sensitivity analysis to several design variables. Central to the use of the model was the tuning of the laminar Arrhenius model constants to match the experimental pressure data over the speed range 13000-20000 rpm. Piston ring crevices lands and valve crevices is shown to be an important development area and connecting rod piston stretch has also been accommodated in the modeling. For the proposed comparison, a conventional 4 valve per cylinder poppet valve engine of nearly equal IMEP has been simulated with GT-POWER.

The specific power densities and therefore the level of sophistication and costs of FIM-MOTOGP engines 800 cm3 in capacity have reached levels similar to those of the traditionally much more expensive FIA-Formula One engines and some racing developments have no application at all in the development of production bikes. The aim of the paper is therefore to review FIM-MOTOGP engine rules and make recommendations that could reduce costs and make racing more directly relevant to the development of production bikes while enhancing the significant interest in technical innovation by the sports' fans.

Gasoline Direct Injection (DI) is a technique that was successful in motor sports several decades ago and is now relatively popular in passenger car applications only. DI gasoline fuel injectors have been recently improved considerably, with much higher fuel flow rates and much finer atomization enabled by the advances in fuel pressure and needle actuation. These improved injector performance and the general interest in reducing fuel consumption also in motor sports have made this option interesting again. This paper compares Port Fuel Injection (PFI) and DI of gasoline fuel in a high performance, four cylinder spark ignition engine for super bike racing. Computations are performed with a code for gas exchange, heat transfer and combustion, simulating turbulent combustion and knock.

The paper compares V10 F1 engine solutions developed in compliance with the 2001 FIA Technical Regulations. Similarity rules and non dimensional parameters from previous projects are used to define geometric and operating parameters for partly similar engine solutions basically differing in the bore/stroke ratio. Five different bore values are considered, B=94, 96, 98, 100 and 102 mm, thus producing bore/stroke ratios B/S=2.176, 2.319, 2.465, 2.621 and 2.779 respectively. Results are presented as computed classical engine outputs versus engine speed, including brake, indicated and friction values. By increasing the bore size, both power output and engine speed for maximum power operation increase. Conversely, only engine speed increases while torque output reduces for maximum torque operation. By using the sharpest car acceleration criteria, the engine with bore B=98 mm reaches the highest score.

The paper compares Road Racing World Championship Grand Prix (WGP) engine solutions developed in compliance with the 2002 Federation Internationale de Motocyclisme (FIM) Technical Regulations. Ad-hoc assumptions, similarity rules and nondimensional parameters from previous projects are used to define geometric and operating parameters for partly similar engine solutions basically differing in the number of cylinders, three, four, five or six, and the cylinder layout, in-line or V-angle. Results are shown as computed classical engine outputs versus engine speed, including brake, indicated and friction values. By increasing the number of cylinders, charging efficiency reduces, while thermal efficiency increases. Higher values of brake torque and power and lower values of brake specific fuel consumption are provided by the V-angle six cylinder engine.

The paper compares 3.0 liter F1 engine solutions developed in compliance with the 1999 FIA Technical Regulations. A previous paper [28] presented a comparison of similar engines having 10 and 12 cylinders. Benefits of the 12 cylinders were clearly shown terms of pure engine performances. W12 engines made up of three banks of four cylinders are further investigated here. Similarity rules are presented first. These rules and non dimensional parameters from previous projects are then used to define geometric and operating parameters for “fully similar” engine solutions differing only in the bore/stroke ratio. Three different bore values are considered, B=89, 90 and 91 mm, thus producing bore/stroke ratios B/S=2.215, 2.290 and 2.367 respectively. These engine solutions are further refined by introducing variation of intake and exhaust pipe diameters and lengths and valve maximum lift and duration, thus producing “partly similar” engine solutions.

The paper compares 3.0 liter F1 engines having different architectures and developed in compliance with the 1998 FIA Technical Regulations. Similarity rules and non dimensional parameters from previous projects define key geometric and operating parameters for V10 and V12 engines having equal degree of sophistication. The paper presents computed classical engine outputs versus engine speed, including brake, indicated and friction values. The V12 solution shows clear advantages in terms of pure engine performances.

The paper describes the fluid dynamic design of the 2.5 liter V6 engine developed by Fiat Auto Corse for the 1996 International Touring Car Series (690 engine). The paper enters into details concerning the definition of valve lift profiles and timings, and provides highlights on the configuration able to optimize the engine in its overall complexity.

The paper describes the fluid dynamic design of the 2.5 liter V6 engine (690) developed by Fiat Auto Corse for the 1996 International Touring Car Series. The paper enters into details concerning the definition of pipe lengths and diameters and provides highlights on the configuration able to optimize the engine in its overall complexity.