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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.

The paper discusses the benefits of a four stroke engine having one intake and one exhaust rotary valve. The rotary valve has a speed of rotation half the crankshaft and defines an open passage that may permit up to extremely sharp opening or closing and very large gas exchange areas. The dual rotary valve design is applied to a racing engine naturally aspirated V-four engine of 1000cc displacement, gasoline fuelled with central direct injection and spark ignition. The engine is then modeled by using a 1D engine & gas dynamics simulation software package to assess the potentials of the solution. The improved design produces much larger power densities than the version of the engines with traditional poppet valves revving at higher speeds, with reduced frictional losses, and with larger gas exchange areas while also improving the fuel conversion efficiency thanks to the sharpness of opening or closing events.

The paper presents a novel design for a two stroke thermal engine that delivers excellent fuel economy and low emissions within the constraints of today's cost, weight and size. The engine features asymmetrical port timing through a novel translating and rotating piston mechanism. The engine is externally scavenged and supercharged, has wet sump and oil pressure lubrication, direct injection, it is lightweight, easy to build, with minimal number of parts, low production cost, ability to be balanced and compact design. The two stroke mechanism produces a linear motion of the pistons as well as an elliptical path on the surface of the cylinder. This allows the piston to sweep as well as travel past the ports. Suitable slots around the raised lip of the piston generate the asymmetry that makes the exhaust port to open first and to close first. The inlet port remains open to complete the cylinder charging and allow supercharging. Direct fuel injection is adopted for best results.

Racing continues to provide the preeminent directive for advancing powertrain development for automakers worldwide. Formula 1, World Rally, and World Endurance Championship all provide engineering teams the most demanding and rigorous testing opportunities for the latest engine and technology designs. Turbocharging has seen significant growth in the passenger car market after years of development on racing circuits. Advances in Turbocharged Racing Engines combines ten essential SAE technical papers with introductory content from the editor on turbocharged engine use in F1, WRC, and WEC-recognizing how forced induction in racing has impacted production vehicle powertrains.

The introduction of advanced internal combustion engine mechanisms and powertrains may improve the fuel conversion efficiency of an engine and thus reduce the amount of energy needed to power the vehicle. 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 induction stroke 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. Results of vehicle driving cycle simulations of a light-duty gasoline vehicle with the advanced engine show dramatic improvements of fuel economy.

Kinetic energy recovery systems (KERS) placed on one axle coupled to a traditional thermal engine on the other axle is possibly the best solution presently available to dramatically improve the fuel economy while providing better performances within strict budget constraints. Different KERS may be built purely electric, purely mechanic, or hybrid mechanic/electric differing for round trip efficiency, packaging, weights, costs and requirement of further research and development. The paper presents an experimental analysis of the energy flow to and from the battery of a latest Nissan Leaf covering the Urban Dynamometer Driving Schedule (UDDS). This analysis provides a state-of-the-art benchmark of the propulsion and regenerative braking efficiencies of electric vehicles with off-the-shelve technologies.

The Wankel engine for Unmanned Aerial Vehicle (UAV) applications delivers advantages vs. piston engines of simplicity, smoothness, compactness and high power-to-weight ratio. The use of computational fluid dynamic (CFD) and computer aided engineering (CAE) tools may permit to address the major downfalls of these engines, namely the slow and incomplete combustion due to the low temperatures and the rotating combustion chambers. The paper proposes the results of CAD/CFD/CAE modelling of a Wankel engine featuring tangential jet ignition to produce faster and more complete combustion.

The paper aims to provide an assessment of the Homogeneous Charge Compression Ignition (HCCI) combustion, compared to a well-established alternative such as Direct Injection Compression Ignition (DICI) combustion, under the criteria of CO2 emission reduction potential. The assessment is performed by reviewing the relevant literature and analyzing the commercial products available on the market that are featuring these two technologies. DICI engines have demonstrated in the real world the ability to deliver top fuel conversion efficiencies of about 50%, and fuel conversion efficiencies largely above 40% over most of the load and speed range. Research-only HCCI engines have delivered fuel efficiencies well below 40% in the very few carefully selected map points where they working during carefully performed laboratory experiments.

The paper discusses the benefits of a four stroke engine having one intake and one exhaust rotary valve. The rotary valve has a speed of rotation half the crankshaft and defines an open passage that may permit up to extremely sharp opening or closing and very large gas exchange areas. This design also permits central direct injection and ignition by spark or jets. The dual rotary valve design is applied to a naturally aspirated V-four engine of 1000cc displacement, gasoline, methane or hydrogen fuelled with central direct injection and spark ignition. The engine is modeled by using a 1D engine & gas dynamics simulation software package to assess the potentials of the solution. The novelty in the proposed dual rotary valve system is the combustion chamber of good shape and high compression ratio with central direct injector and spark plug or jet ignition, coupled to the large gas exchange areas of the rotary system.

Moto GP engines have since the year 2012 4 cylinders in V or inline layout for a total capacity of up to 1,000cc. With pneumatic valve spring but wet sump, and with the maximum bore limited to 81mm, the maximum speed these engines may have is about 18,000 rpm, with power outputs 250-260 HP. The paper presents the design of a 65 degree V4 Moto GP engine further optimizing the pneumatic poppet valve design, as well as a novel rotary valve design. The rotary valve permits up to extremely sharp opening or closing and very large gas exchange areas. The two engines are then modeled by using a 1D engine & gas dynamics simulation software package to assess the potentials of the solution. The improved design produces much larger power densities than the version of the engines with traditional poppet valves revving at higher speeds.

Jet ignition and direct fuel injection are potential enablers of higher efficiency, cleaner Internal Combustion Engines (ICE). Very lean mixtures of gaseous fuels could be burned with pollutants formation below Euro 6 levels (in the ultra-lean mode), efficiencies approaching 50% full load and small efficiency penalties when operating part load. The lean burn Direct Injection Jet Ignition (DI-JI) ICE uses a fuel injection and mixture ignition system comprising one main chamber direct fuel injector and one small-size jet ignition pre-chamber per engine cylinder. The jet ignition pre-chamber is connected to the main chamber through calibrated orifices and accommodates a second direct fuel injector. In the spark plug version, the jet ignition pre-chamber includes a spark plug that ignites the slightly rich pre-chamber mixture that then bulk ignites the ultra lean, stratified main chamber mixture through multiple jets of hot reacting gases entering the in-cylinder.

The World Championship Grand Prix (WCGP) is the premier championship event of motorcycle road racing. The WCGP was established in 1949 by the sport's governing body, the Fédération Internationale de Motocyclisme (FIM), and is the oldest world championship event in the motorsports arena. This book, developed especially for racing enthusiasts by motorsports engineering expert Dr. Alberto Boretti, provides a broad view of WCGP motorcycle racing and vehicles, but is primarily focused on the design of four-stroke engines for the MotoGP class. The book opens with general background on MotoGP governing bodies and a history of the event’s classes since the competition began in 1949. It then presents some of the key engines that have been developed and used for the competition through the years. Technologies that are used in today’s MotoGP engines are discussed.

The Atkinson cycle engine is basically an engine permitting the strokes to be different lengths for improved light loads fuel economies. Variable compression ratio is the technology to adjust internal combustion engine cylinder compression ratio to increase fuel efficiency while under varying loads. The paper presents a new design of a variable compression ratio 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.

Variable compression ratio is the technology to adjust internal combustion engine cylinder compression ratio to increase fuel efficiency while under varying loads. The paper presents a new design of a variable compression ratio engine that allows for the volume above the piston at Top Dead Centre (TDC) to be changed. A modeling study is then performed using the WAVE engine performance simulation code for a naturally aspirated gasoline V8 engine. The modeling study shows significant improvements of fuel economy over the full range of loads and especially during light loads operation as well as an improvement of top power and torque outputs.

The consumption of fossil fuels is one of the largest problems facing humankind. One of the heaviest users of non-renewable energy sources is the transport industry. Tightening worldwide legislation aims to place restrictions on the transport industry to reduce its use of fossil fuels and reduce the levels of pollution being released to the atmosphere. Although several different alternatives to the vehicles only powered by internal combustion engine (ICEs) have been investigated, none have as yet become equally widespread. Alternative research into development of hybrid vehicles was specifically concerned with electric hybrids especially for passenger vehicles. Currently there is a resurgence of interest in the Hybrid Hydraulic Vehicle (HHV) in application to commercial and to a lesser degree to passenger vehicles. This paper gives an overview of hydraulic hybrid technology.

Improvements of truck fuel economy are being considered using a flywheel energy storage system concept. This system reduces the amount of mechanical energy needed by the thermal engine by recovering the vehicle kinetic energy during braking and then assisting torque requirements. The mechanical system has an overall efficiency over a full regenerative cycle of about 70%, about twice the efficiency of battery-based hybrids rated at about 36%. The technology may improve the vehicle fuel economy and hence reduced CO₂ emissions by more than 30% over driving cycles characterized by: frequent engine start/stop, vehicle acceleration, brief cruising, deceleration and stop. The paper uses engine and vehicle simulations to compute: first the fuel benefits of the technology applied to passenger cars, then the extension of the technology to deal with heavy-duty vehicles.

The turbocharged direct injection stoichiometric spark ignition gasoline engine has less than Diesel full load brake engine thermal efficiencies and much larger than Diesel penalties in brake engine thermal efficiencies reducing the load by throttling. This engine has however a much better power density, and therefore may operate at much higher BMEP values over driving cycles reducing the fuel economy penalty of the vehicle. This engine also has the advantage of the very well developed three way catalytic converter after treatment to meet future emission regulations. In these engines the efficiency may be improved recovering the waste heat, but this recovery may have ultimately impacts on both the in cylinder fuel conversion efficiency and the efficiency of the after treatment.

Direct injection (DI) and jet ignition (JI), plus assisted turbocharging, have been demonstrated to deliver high efficiency, high power density positive ignition (PI) internal combustion engines (ICEs) with gasoline. Peak efficiency above 50% and power density of 340 kW/liter at the 15,000 rpm revolution limiter working overall λ=1.45 have been report-ed. Here we explore the further improvement in power density that may be obtained by replacing gasoline with ethanol or methanol, thanks to the higher octane number and the larger latent heat of vaporization, which translates in an increased resistance to knock, and permits to have larger compression ratios. Results of simulations are proposed for a numerical engine that uses rotary valves rather than poppet valves, while also using mechanical, rather than electric, assisted turbocharging. While with gasoline, the power density is 410-420 kW/liter, the use of oxygenates permits to achieve up to 475 kW/liter working with methanol.

Recovery of kinetic energy during driving cycles is the most effective option to improve fuel economy and reduce green house gas (GHG) emissions. Flywheel kinetic energy recovery systems (KERS) may boost this efficiency up to values of about 70%. An engine and vehicle model is developed to simulate the fuel economy of a compact car equipped with a TDI diesel engine and a KERS. Introduction of KERS reduces the fuel used by the 1.6L TDI engine to 3.16 liters per 100 km, corresponding to 82.4 g of CO₂ per km. Downsizing the engine to 1.2 liters as permitted by the torque assistance by KERS, further reduces the fuel consumption to 3.04 liters per 100 km, corresponding to 79.2 g of CO₂ per km. These CO₂ values are 11% better than those of today's most fuel efficient hybrid electric vehicle.

Improvements of vehicle fuel economy may be achieved by the introduction of advanced internal combustion engines (ICE) improving the fuel conversion efficiency of the engine and of advanced power trains (PWT) reducing the amount of fuel energy needed to power the vehicle. 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 hence 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 torque output of the engine.