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The conventional Diesel cycles engine is now approaching the practical limits of efficiency. The recuperated split cycle engine is an alternative cycle with the potential to achieve higher efficiencies than could be achieved using a conventional engine cycle. In a split cycle engine, the compression and combustion strokes are performed in separate chambers. This enables direct cooling of the compression cylinder reducing compression work, intra cycle heat recovery and low heat rejection expansion. Previously reported analysis has shown that brake efficiencies approaching 60% are attainable, representing a 33% improvement over current advanced heavy duty diesel engine. However, the achievement of complete, stable, compression ignited combustion has remained elusive to date.

There is much interest and debate on which advanced vehicle technologies will be common in the future. Public expectations seem to be running high with great promise of non-polluting, high efficiency vehicles. For the vehicles to reach high volume production though, the characteristics of these vehicles will need to meet customer demands for price, performance, driveability and comfort. The ideal propulsion system solution may well be different for the various vehicle applications (SUV, passenger car, city bus) as well as in different world markets. Currently there appears to be a significant divide between the benefits of hybrid vehicles and the incremental price consumers may be willing to pay. This raises the question as to what type of hybrids will be seen on the roads in the future. This paper reviews the future advanced vehicle concepts and focuses on the probable prime candidate for near term mass market - the mild hybrid.

As part of an ongoing investigation, the influence of in-cylinder charge density, and injector nozzle geometry on the behaviour of diesel sprays were examined using high-speed imaging. Both liquid and vapour penetration profiles were investigated in operating conditions representative of a modern turbocharged after-cooled HSDI diesel engine. These conditions were achieved in an optical rapid compression machine fitted with a common rail fuel injection system. Differences in spray liquid and vapour penetrations were observed for different nozzle geometries and in-cylinder conditions over a range of injection fuelling representative of those in a typical engine map. Investigation into the differences in spray structure formed by multi-hole and single-hole injections were also undertaken.

If fuel cell vehicles are to compete in the same marketplace as conventional vehicles, then they must provide the consumer with the same, or improved, levels of convenience, comfort, refinement and performance at the same, or lower, price. In 2003/4, several vehicle manufacturers are planning to launch their first commercial fuel cell vehicles onto the market. In this remarkably short timeframe, many systems must be integrated into a vehicle including the fuel cell system plus thermal and water management, cabin heating, ventilation and air-conditioning, control and on-board diagnostics, power electronics, electric motor and gearbox, suspension, steering, braking, refinement and crash protection. This paper presents a range of modelling techniques which allow the user to design and develop key systems, including the power management system, compressed air supply, thermal management and control algorithms.