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This paper describes a model for EGR mass flow rate estimation as a function of signal smeasured by existing sensors in an internal combustion electronically controlled engine. An original approach is presented to take into account the heat transfer between the EGR duct and the environment. The preliminary results relative to EGR mass flow rate estimation suggest that the methodology may be extended towards the development of a complete model of the intake manifold including the EGR recirculation system and the purge canister.

The present paper describes a study of the basic parameters, which govern particulate (soot) formation within the combustion chamber of a small displacement (1.3 liter) turbocharged European CR-diesel engine. The main tools used for the study are a real fired engine, a numerical virtual engine and a special high ambient pressure vessel for injector spray visualization. The paper describes an improved soot formation model implemented in the virtual engine setup. A comparison is presented between measured and computed combustion data at 8 different load points. The paper concludes with a discussion of the means, which can be used to minimize the particulate matter formation in the design phase of both the combustion layout and the fuel injector atomizer as well as in the design of the injection control strategies.

New engine control strategies, designed for drive-by-wire systems, will require the measurement (or the estimation) of several operative engine parameters in order to control emissions and efficiency, while satisfying the driver demand in terms of driveability and performance. Both load and indicated torque (i.e. the torque due to the gas pressure acting on the pistons) will play an essential role in this context, since the driver pedal command may be appropriately interpreted by the Electronic Control Unit (ECU) in terms of an engine (or load) torque request. In fact, the accelerator pedal variation forces the vehicle to reach a final steady-state condition, corresponding to a new level of engine and load torques, thus making it possible to assume the existence of a direct link between the pedal position and the “desired” final engine (or load) torque.