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Recently Piaggio developed a new scooter equipped with a revolutionary front suspension electronically controlled locking. It was critical to test and validate the design of this new control system before deployment to ensure high customer satisfaction and reducing warranty costs. Test on a HIL platform accelerates the verification and validation process. A validated HIL set-up, being a repeatable and reliable test platform with a short turnaround time is ideal for developing standardized processes for Electronic Control Unit (ECU) testing and calibration. With shortening life cycles in the motorcycle industry, HIL technology is rapidly gaining acceptance not only in conventional vehicle programs, but also challenging vehicle programs. The development of control strategies for MP3 ECU has benefited from HIL-based testing. It has proven to be an efficient tool for software strategy development, implementation and validation.

The paper deals with the development of a multi-zone phenomenological model for the combustion process in a common rail multi-injection Diesel engine. The model simulates the fuel jet and its interaction with surrounding gases by dividing the jet core into many parcels in order to describe the thermal gradient and the chemical composition within the combustion chamber. This is mandatory for the simulation of the NO pollutant formation, carried out via the Zeldovich mechanism. The air entrainment into the fuel jet is modeled by means of the momentum balance applied to each zone and to the air zone. The stratification of the chemical composition within the cylinder and the details of the spray and its interaction with the air zone are simulated to estimate the spray penetration and speed, the mass of entrained air and the equivalence ratio in each zone. The combustion model is based on the laminar-and-turbulent characteristic-time approach.

A two zones combustion model suitable for the engine control design of common rail multi-jet Diesel engines is presented. The modeling approach is based on a semi-empirical two-zone combustion model coupled with identification analysis in order to implement a predictive tool for simulating the effects of control injection strategies on combustion and exhaust emissions. Fuel jet formation and combustion for both premixed and diffusive regimes are predicted, by dividing the combustion chamber into two control volumes; these account for the fuel jet and the surrounding air, composed by fresh air and residual gases; the fuel jet is divided into two zones to separate liquid and vapor phases. The simulation results have shown that the model predicts the effects of different injection parameters in case of single and multiple injection in a short computational time, suitable for the accomplishment of intensive simulations or optimization analyses over generic engine driving cycles.

The paper deals with the development of a system of phenomenological models for the simulation of combustion and NOx-Soot emissions in Common-Rail Multi-Jet Diesel engines. The system has been built by following a modular modeling approach and is suitable for the implementation in the framework of Hardware In the Loop (HIL) ECU rapid prototyping. A single-zone model simulates the ignition delay and the combustion during a sequence of pilot, pre and main fuel injections for a production 1,9 liters Diesel engine equipped with High Pressure Injection system, electronically controlled. The heat release model is based on the synthetic description of both premixed and diffusive combustion. The Zeldovich mechanism has been used to simulate the formation of NO emissions while the Soot model is based on the approach proposed by Hiroyasu. The models have been tested vs. a wide set of experimental data with a good accuracy in predicting pressure cycle and heat release.

In order to improve the emission and performance capabilities of modern engines several devices are introduced in the system. One of such devices is the Continuously Variable Cam Phaser (CVCP), which, by shifting the relative angle between the crank and cam shafts, allows to modify the opening and closing times of the inlet and outlet valves with respect to the base engine configuration, thus giving more design freedom. The control of the CVCP is performed by the Engine Control Unit, which both sets the desired values for the CVCP shift angle and commands the CVCP actuator to control it at the correct position. The new FIRE engine 1.4l 16v also includes a CVCP. The aim of the activity described in the paper was to perform a functional validation of the CVCP position control algorithms, through a sensitivity analysis of the CVCP control performance to a series of environmental and production variables.

The paper describes the research work carried out on the thermo-fluid dynamic modeling of an S.I. engine coupled to the vehicle in order to predict the engine and tailpipe emissions during the ECE European driving cycle. The numerical code GASDYN has been extended to simulate the engine + vehicle operation during the first 90 seconds of the NEDC driving cycle, taking account of the engine and exhaust system warm-up after the cold start. The chemical composition of the engine exhaust gas is calculated by means of a thermodynamic multi-zone combustion model, augmented by kinetic emission sub-models for the prediction of pollutant emissions. A simple procedure has been implemented to model the vehicle dynamic behavior (one degree of freedom model). A closed-loop control strategy (proportional-derivative) has been introduced to determine the throttle opening angle, corresponding to the engine operating point when the vehicle is following the ECE cycle.

In the world of automotive control and electronics, technology is the driving force behind every decrease in product cycle time. Cost and time to market are crucial factors to ensure continued success in a competitive world where products must be tailored precisely to the customers' needs. To achieve these goals, co-operation between suppliers and vehicle manufacturers need to reach unprecedented levels through the use of common tools. This paper aims to show the competitive edge that may be derived from using current state-of-the-art control development tools and methodologies. The tools shift the emphasis away from expensive on-vehicle work to lever the power of simulation and engine emulation in the development of a prototype EMS (Engine Management System) controller.

A wide experimental investigation on a 16 valves, 1242 cm3 SI-engine is reported. Experimental data were collected in correspondence with about 250 different operating conditions of the engine. This allowed to deeply assess the accuracy of a simulation model (1Dime code), developed by the authors, based on a one-dimensional computation of the gas flow in the manifolds, and on a quasi-dimensional fractal approach for combustion simulation. The model is then employed to theoretically verify the advantages that can be exploited from the adoption of various VVT (Variable Valve Timing) or VVA (Variable Valve Actuation) systems, including those realizing a throttle-less operation of the engine. The gains predicted in terms of torque profile at WOT, and of BSFC or NOx emissions at part load are quantified and discussed.

As U.S. and European regulation of automotive emissions is getting more stringent, great interest is growing around new solutions for future emission standards. Pollutant reduction can be achieved improving both engine out emission and aftertreatment system efficiency. Engine out emission can be reduced improving combustion process especially during warm-up, friction and the engine management system. In any case engine out emission reduction involves engine sophistication increasing costs, which must be accurately evaluated, especially for small displacement large mass production engine. Since, as it is well known, 80 - 90 per cent of HC and CO emissions are produced during the first 100s of NEDC cycle, great improvement could be achieved reducing the catalyst light-off time. Different configurations of exhaust gas after treatment system have been tested to improve conversion efficiency during warm-up phases.

The new European Legislation requires new strategies in order to achieve a reliable emission diagnostic over the entire life of the vehicle (EOBD). For the validation and the fine-tuning of the new diagnostic controls, the car manufacturers must manage fleets of vehicles in order to evaluate the behavior of these diagnostics over a real aging cycle. This paper describes a useful tool that has been developed to check the most important diagnostic indexes behavior with aging, that help us in the management of a durability fleet. The system is composed of: a specific hardware added to the Engine Control Unit (ECU) a real time software for the automatic storage of the most important diagnostic parameters an off line software for data analysis. During the use of durability car the system runs automatically and does not require any additional operation to the driver (“black-box system”), and no additional skilled people is required for the data acquisition.