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Gasoline engine downsizing is already established as a proven technology to reduce automotive fleet CO₂ emissions. Further real-world benefits are possible through more aggressive downsizing; however, there is a trade-off between maintaining a high compression ratio for good part load fuel consumption and maintaining optimal combustion phasing at higher loads. There are many different technologies, which could be applied to gasoline-downsized engines in order to improve efficiency. One is to adopt a Miller/Atkinson cycle, which uses variable valve timing to reduce throttling losses in part load operation and reduce effective compression ratio to optimize combustion phasing at higher loads. MAHLE Intake CamInCam® is a technology enabler for Miller/Atkinson cycle operation. It uses asymmetric intake valve timing control to effectively provide a method of running increased intake cam duration allowing Late Intake Valve Closing cycle strategies to be adopted.

Current focus on techniques to reduce the tailpipe CO₂ emissions of road vehicles is increasing the interest in hybrid and electric vehicle technologies. Pure electric vehicles require bulky, heavy, and expensive battery packs to enable an acceptable drive-able range to be achieved. Extended-range electric vehicles (E-REV) partly overcome the limitations of current battery technology by having a "range extender" unit, which consists of an onboard fuel converter that converts a liquid fuel, such as gasoline, into electrical energy whilst the vehicle is driving. This enables the traction battery storage capacity to be reduced, whilst still maintaining an acceptable vehicle driving range. In a previous paper the power requirement of a range extender for a typical C segment passenger car was investigated using drive-cycle modeling over real-world cycles. This paper presents the detailed design of the range extender engine.

In-cylinder air flow structures are known to play a major role in mixture preparation and engine operating limits for DISI engines. In this paper PIV was undertaken on in-cylinder flow fields for three different planes of measurement in the intake and compression strokes of a DISI engine for a low-load engine operating condition at 1500 RPM, 0.5 bar inlet plenum pressure (World Wide Mapping Point). One of these planes was vertical, cutting through the centrally located spark plug (tumble plane); the other two planes were horizontal, one close to TDC (10 mm below fire face) and the other one close to mid stroke (50 mm below fire face). Statistical analysis was undertaken on the numbers of cycles needed to determine ensemble average flow-field and turbulent kinetic energy maps with up to 1200 cycles considered. The effect of engine head temperature was also examined by obtaining flow fields using PIV with the engine head coolant held at 20 °C and 80 °C.