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In order to meet the legislated emissions levels, future diesel engines will likely utilize cooled exhaust gas re-circulation (EGR) to reduce emissions. The addition of the EGR cooler to the conventional vehicle coolant system creates several challenges. Firstly, the engine cooling system flow and heat rejection requirements both increase as it is likely that some EGR will be required at the rated power condition. This adversely affects packaging and fuel economy. The system design is further complicated by the fact that the peak duty of the EGR cooler occurs at part load, low speed conditions, whereas the cooling system is traditionally designed to handle maximum heat duties at the rated power condition of the engine. To address the system design challenges, Ricardo have undertaken an analytical study to evaluate the performance of different cooling system strategies which incorporate EGR coolers.

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.

A flow and heat transfer model of an engine lubrication system has been developed in order to predict sump oil temperature and study heat transfer mechanisms within the lubricating oil circuit. The objective was to develop the capability of simulating all the energy transfers between the oil and the combustion process, the engine coolant, and the engine bay air. The model developed in this study simulates a V8 spark ignited engine. Included in this simulation is a bearing model for friction heat generation, a combustion heat input model, and component models for each key heat transfer site in the lubricating oil circuit. The model predicts sump oil temperatures under different engine operating conditions and simulation results were compared to test data with good agreement. The sensitivity of oil temperature to engine speed, engine load, coolant temperature, piston friction, bearing heat energy generation, piston design, water jacket depth, and oil flow rate(s) was studied.