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Power train cooling control is becoming a topic of increasing interest as evidenced by the recent surge of activities that suppliers of automotive power train cooling and HVAC systems are reporting in literature. The goals of these activities are to achieve better fuel economy, lower emissions and increased passenger comfort by controlling coolant flow through the different system components. In order to study any of the ideas in this area, a simulation model must be developed to sift through them for the most practical and effective method to avoid the high cost of hardware builds and long testing hours. This work uses the EASY5 simulation package (a product of the Boeing Company) to model such systems. A model is developed for a pick up truck application and is validated against test results. At this stage, the model has only the basic components namely the radiator, the water pump, a surge (return) tank, hoses and pipes, and the engine thermal load.

This paper explores issues related with the design and implementation of belt-driven starter-generators for future 42-V systems. Belt-driven starter-generators can offer many advantages including smooth restarts, high efficiency, and convenient packaging. Future vehicle systems require these characteristics to enable fuel economy functions like “engine off at idle” and “x-by-wire.” Belt-driven starter-generators are often easier to package in contrast with flywheel-mounted systems, which require powertrain modifications and in many cases a longer package. A prototype system based on a belt-driven induction machine mounted on a small, European engine is described in the paper. Test results for both cranking and generation are shown and analyzed. Efficient, high-power generation was confirmed and high-speed (beyond 400 engine rpm) cranking was demonstrated down to the targeted -20°C.

A novel mechanism concept for a fully flexible, motor-driven, cam-actuated engine valve was reported in [1]. It is capable of i) variable valve timing, ii) variable lift and iii) individual valve phasing control. To check the validity of the concept in real engine environment, engine tests were performed using a single-cylinder of a modified six-cylinder 3.8-liter production engine, with the new motor-driven mechanisms replacing both valves. Firing tests of this engine, with equivalent valve profiles to the production profiles, yielded similar fuel consumption, lower NOx emissions but higher IMEP COV and HC emissions. Motoring tests demonstrated variable timing capability, low cycle-to-cycle valve lift-profile variation as well as low seating velocity and noise. Lessons learned from testing the system in a real engine environment are discussed in details and suggestions for future variable-valve actuation concepts' requirements are offered.

A novel, fully flexible engine valve actuation mechanism was built and tested for the first time. It consists of a permanent magnet brushless dc motor driving a cam mechanism to actuate each engine poppet valve. This mechanism has the advantages of low friction, low seating velocity and speed range comparable to that of production valve trains. The electromechanical system has also regeneration capabilities which result in an energy requirement that is equivalent to or lower than the valve-train friction of current production engines. The valve event duration is changed by increasing or decreasing the cam/motor angular velocity during valve opening in order to shorten or lengthen the valve event, respectively. Part-lift operation is also possible by oscillating the mechanism around the valve opening or closing points. The prototype mechanism was run on the bench on an actual engine cylinder head at speeds of up to 3225 r/min, equivalent to 6450 engine r/min.