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Due to the rising costs of fuel and increasingly stringent regulations, auto makers are in need of technology to enable more fuel-efficient powertrain technologies to be introduced to the marketplace. Such powertrains must not sacrifice performance, safety or driver comfort. Today's engine and powertrain manufacturers must, therefore, do more with less by achieving acceptable vehicle performance while reducing fuel consumption. One effective method to achieve this is the extreme downsizing of current direct injection spark ignited (DISI) engines through the use of high levels of boosting and cooled exhaust gas recirculation (EGR). Key challenges to highly downsized gasoline engines are retarded combustion to prevent engine knocking and the necessity to operate at air/fuel ratios that are significantly richer than the stoichiometric ratio.

The Ethanol-Boosted Direct Injection (EBDI) demonstrator engine is a collaborative project led by Ricardo targeted at reducing the fuel consumption of a spark-ignited engine. This paper describes the design challenges to upgrade an existing engine architecture and the synergistic use of a combination of technologies that allows a significant reduction in fuel consumption and CO₂ emissions. Features include an extremely reduced displacement for the target vehicle, 180 bar cylinder pressure capability, cooled exhaust gas recirculation, advanced boosting concepts and direct injection. Precise harmonization of these individual technologies and control algorithms provide optimized operation on gasoline of varying octane and ethanol content.

In relation to further tightening of the emissions legislation for on-road heavy duty Diesel engines, the future potential of cooled exhaust gas recirculation (EGR) as a result of developments in the cooling systems of such engines has been evaluated. Four basic engine concepts were investigated: an engine with SCR exhaust gas aftertreatment for control of the nitrogen oxides (NOx), an engine with cooled EGR and particulate (PM) filtration, an engine with low pressure EGR and PM filtration and an engine with two stage low temperature cooled EGR also with a particulate filter. A 10.5 litre engine was calibrated and tested under conditions representative for each concept, such that 1.7 g/kWh (1.3 g/bhp-hr) NOx could be achieved over the ESC and ETC. This corresponds to emissions 15% below the Euro 5 legislation level.

This paper gives a brief overview of the Behr reliability management system, including, as an integral element, the validation process. It describes the application of test methods as well as simulation tools and associated coupling strategies which are used to validate charge air coolers. Simulation of the main validation tests for charge air coolers are performed. For this study a CFD simulation is carried out to predict surface temperature distribution. The results are evaluated and compared with temperature measurements from an infrared camera. By mapping these temperature distributions, obtained either from computations or measurements, onto an FE model as boundary conditions, structural analyses are performed for the thermal cycle test. The stresses computed are compared with strain gage measurements from the test rig.

Due to increasing durability requirements driven by engine emission regulations such as Euro 5 and US'07, the reliability of the engine cooling equipment, especially of charge-air-to-air-cooler (CAC), has to be increased as well. Behr is using reliability management in order to meet these requirements. “Reliability” is defined as the fulfillment of quality requirements over the life cycle and under specific application conditions. At Behr, the reliability management is organized as a “House of Reliability” (HOR). The mission profile includes up-to-date customer requirements, loads and statistical experience from the field and helps to create relevant test specifications for the validation testing. Validation is one key element of the HOR. If the test specifications are not connected to the field, the testing will not lead to a reliable product and to customer satisfaction. The process of gathering load collectives for mission profiles is therefore very important.