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In 2012 MAHLE Powertrain developed a range-extended electric vehicle (REEV) demonstrator, based on a series hybrid configuration, and uses a battery to store electrical energy from the grid. Once the battery state of charge (SOC) is depleted a gasoline engine (range extender) is activated to provide the energy required to propel the vehicle. As part of the continuing development of this vehicle, MAHLE Powertrain has developed control software which can intelligently manage the use of the battery energy through the combined use of GPS and road topographical data. Advanced knowledge of the route prior to the start of a journey enables the software to calculate the SOC throughout the journey and pre-determine the optimum operating strategy for the range extender to enable best charging efficiency and minimize NVH. The software can also operate without a pre-determined route being selected.

Emissions legislation, fleet CO₂ targets and customer demands are driving the requirements for reducing fuel consumption. This is being achieved in the gasoline market in the near term through the adoption of engine downsizing. In order to reduce fuel consumption further and in the wider real-world operating region complimentary technologies are being investigated and applied to an extreme downsized engine. In this paper future gasoline engine technologies are applied and experimentally assessed in terms of fuel consumption improvement whilst the impact of subsequent loadings on the thermal management system have been simulated, both over drive cycle and using real-world drive data.

The open MAHLE Flexible ECU (MFE) was developed and successfully implemented for controlling gasoline, diesel and hybrid engines. The increased demand of new functions development to address future powertrain challenges, such as lower fuel consumption, ever more stringent emissions legislative targets as well as the need to reduce development time and cost at the same time, led to the incorporation of the MFE functions in a co-simulation environment. The co-simulation environment consists of using the virtual engine developed with 1D or 3D numerical simulation tools and the functions of MFE developed with Simulink-Targetlink. This co-simulation approach allows modifying either the engine control or the engine itself. Regarding the engine control and its development, the existing and new functions were tested for the performance, emissions and behaviour changes on several production and prototype engines.

Concerns over greenhouse gas emissions are driving governments and the automotive industry to seek out ways of reducing vehicle CO₂ emissions. Engine friction reduction is one means of reducing CO₂ emissions, through fuel consumption improvements. Of the different systems within the engine, the camshaft timing drive can contribute around 5 to 10% of the overall engine friction. It is therefore a system that can benefit from careful optimization. MAHLE has undertaken a motored friction-testing program on a 2.2-liter turbocharged diesel engine with the following different types of camshaft timing drive: - Chain drive with hydraulic tensioner. This is the standard configuration for this engine. - Chain drive with friction tensioner. - Wet belt drive. - Dry belt drive. Testing was conducted to allow the differences in friction between the different drive configurations to be calculated, by comparing each camshaft drive against the standard chain drive system.

An unmodified, conventionally fuelled, 2009 Class D vehicle with a 2.0L turbocharged gasoline direct injection engine was operated on a range of gasoline, gasoline-ethanol and gasoline-butanol fuel blends over NEDC drive cycles and WOT power curves on a chassis dynamometer. Engine performance, engine management system parameters and vehicle out emissions were recorded to investigate the response of a current state-of-the-art technology vehicle to various alcohol fuel blends. The vehicle fired on all fuels and was capable of adapting its long term fuelling trim to cope with the increased fuel flow demand for alcohol fuels up to E85. Over the NEDC tests, the volumetric fuel consumption was very strongly related to the calorific content of the fuel. CO and NOx emissions were largely unaffected for the mid alcohol blends, but CO emissions decreased and NOx emissions increased significantly for the high alcohol fuels. THC emissions were largely unaffected.

Concerns over greenhouse gas emissions are driving governments and the automotive industry to seek out ways of reducing vehicle CO₂ emissions. Engine friction reduction is one means of reducing CO₂ emissions, through fuel consumption improvements. The ancillary drive system typically contributes up to 8% of the total engine friction level, so improvements in this system can make a real difference to engine efficiency, fuel consumption and CO₂ emissions. Mahle has undertaken a series of rig tests, based on a 2.5-liter gasoline engine, but built to a minimum friction level of hardware. Using motored drive torques, the losses associated with different alternator drive concepts was investigated: - Standard 150A alternator, - Reduced capacity 120A alternator, - Reduced capacity 120A alternator driven by a dual speed gearbox, and - Reduced capacity 120A alternator driven by a twin-belt dual ratio pulley.

Concerns over greenhouse gas emissions are driving governments and the automotive industry to seek out ways of reducing vehicle CO₂ emissions. Engine friction reduction is one means of reducing CO₂ emissions, through fuel consumption improvements. One area where it is felt that friction reduction is possible is in connection with the camshaft bearings. Mahle has conducted experimental evaluation of rolling element bearings used to support camshafts, replacing the standard plain journal bearings. The aim of the testing was to gain an understanding of the durability of rolling element bearings, tested in a range of different operating conditions. The controlled test conditions included variations to: - Camshaft speed, - Oil temperature, - Oil age/specification, - Oil supply method/flowrate, - Bearing journal line bore misalignment tolerance, and - Bearing journal diametrical tolerance.

Concerns over greenhouse gas emissions are driving governments and the automotive industry to seek out ways of reducing vehicle CO₂ emissions. Engine friction reduction is one means of reducing CO₂ emissions, through fuel consumption improvements. One area where it is felt that friction reduction is possible is in connection with the camshaft bearings. The use of rolling element bearings is generally considered to provide friction reductions by two means: 1. As a direct substitution of the journal bearings by rolling element bearings and 2. As an enabling opportunity to reduce the oil flow requirement of the engine. MAHLE has undertaken a motored friction-testing program on a 2.5-liter gasoline engine, comparing the drive torques associated with the standard camshaft bearings and also with camshafts supported by rolling element bearings. The test engine incorporated a direct-acting valve train design.