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The paper discusses the concept, design and final results from the ‘Ultra Boost for Economy’ collaborative project, which was part-funded by the Technology Strategy Board, the UK's innovation agency. The project comprised industry- and academia-wide expertise to demonstrate that it is possible to reduce engine capacity by 60% and still achieve the torque curve of a modern, large-capacity naturally-aspirated engine, while encompassing the attributes necessary to employ such a concept in premium vehicles. In addition to achieving the torque curve of the Jaguar Land Rover naturally-aspirated 5.0 litre V8 engine (which included generating 25 bar BMEP at 1000 rpm), the main project target was to show that such a downsized engine could, in itself, provide a major proportion of a route towards a 35% reduction in vehicle tailpipe CO2 on the New European Drive Cycle, together with some vehicle-based modifications and the assumption of stop-start technology being used instead of hybridization.

Extensive literature exists on spray development, mixing and combustion regarding engine modeling and diagnostics using single-component and model fuels. However, often the variation in data between different fuels, particularly relating to spray development and its effect on combustion, is neglected or overlooked. By injecting into a quiescent chamber, this work quantifies the differences in spray development from a multi-hole direct-injection spark-ignition engine injector for two single-component fuels (iso-octane and n-pentane), a non-fluorescing multi-component model fuel which may be used for in-cylinder Laser Induced Fluorescence experiments, and several grades of pump gasoline (with and without additives). High-speed recordings of the sprays were made for a range of fuel temperatures and gas pressures. It is shown that a fuel temperature above that of the lowest boiling point fraction of the tested fuel at the given gas pressure causes a convergence of the spray plumes.

In this paper different air management system concepts including mechanical superchargers and turbochargers are analysed with regard to their suitability for fuel cell applications. Therefore a simulation model which takes the main mass, energy and heat flows in the fuel cell system including fuel evaporation, reformer, gas cleaning, humidification, burner and compressor/expander unit into account was setup. For a PEM system with methanol steam reformer the best system efficiencies at rated power can be achieved with a turbocharger in combination with a tailgas burner for operating pressures between 2.5 and 2.8 bar. For pure hydrogen systems the best system efficiency is obtained with an electric driven supercharger for a maximum pressure of 2 bar and an appropriate pressure strategy during part load operation in the complete operating range. The increase of system efficiency for pressurized stack operation is mainly attributed to advantages with regard to water management.

From current point of view future emission legislations for heavy-duty engines as well as industrial engines will require complex engine internal measures in combination with sophisticated aftertreatment systems as well as according control strategies to reach the emission targets. With EU VI, JP 09/NLT and US10 for heavy-duty engines as well as future Tier4 final or stage IV emission legislation for industrial applications, EGR + DPF + SCR probably will be combined for most applications and therefore quite similar technological approaches will be followed up in Europe as well as in the US and in Japan. Most “emerging markets” all over the world follow up the European, US or Japanese emission legislation with a certain time delay. Therefore similar technologies need to be introduced in these markets in the future. On the other hand specific market boundary conditions and requirements have to be considered for the development of tailored system concepts in these markets.

Future vehicles will increasingly be required to improve their efficiency, reduce both regulated and CO₂ emissions, and maintain acceptable levels of driving, safety, and noise performance. To achieve this high level of performance, they will be configured with more advanced hardware, sensors, and control technologies that will also enable their operation on a broader range of fuel properties. These capabilities offer the potential to design future vehicles to operate on the most widely available and GHG-reducing fuels. In previous studies, fuel flexibility has been demonstrated on a compression ignition bench engine and vehicle equipped with an advanced engine management system, closed-loop combustion control, and air-path control strategies. An unresolved question is whether engines of this sort can operate routinely on market gasoline while achieving diesel-like efficiency and acceptable emissions and noise levels.

A light extinction technique has been applied to the direct injection Diesel combustion process under simplified engine-like boundary conditions in a model combustion chamber. The combination of these experimental tools proved to provide excellent data about the time and space resolved soot formation and oxidation processes in Diesel sprays. The importance of the injection history with regard to low soot emissions is pointed out by time and local resolved soot mass concentrations, the behaviour of total mass of soot in the spray and mean soot formation/oxidation rates for different injection rates, nozzle opening pressures and nozzle geometries.

In this paper different compressor/expander concepts including mechanical superchargers, turbochargers and two-stage charging concepts are analysed with regard to their suitability for fuel cell applications. Special attention is focused on system designs which use the energy of the tail gases for driving the compressor. The net efficiencies of different system concepts at full load were calculated with a simulation model, based on Matlab/Simulink‘ and show, that with a single stage turbocharger in combination with a tail gas burner good efficiencies and high power densities can be obtained at a pressure level of more than 2.5 bar.