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Over the years numerous researchers have suggested that the ionization current signal carries within it combustion relevant information. The possibility of using this signal for diagnostics and control provides motivation for continued research in this area. To be able to use the ion current signal for feedback control a reliable estimate of some combustion related parameter is necessary and therein lies the difficulty. Given the nature of the ion current signal this is not a trivial task. Fei An et al. [1] employed PCA for feature extraction and then used these feature vectors to design a neural network based classifier for the estimation of air to fuel ratio (AFR). Although the classifier predicted AFR with sufficient reliability, a major draw back was that the ion current signals used for prediction were averaged signals thus precluding a cycle to cycle estimate of AFR.

This paper presents the development of a model-based air/fuel ratio controller for a high performance engine that uses, in addition to other usual signals, the throttle angle to enable predictive air mass flow rate estimation. The objective of the paper is to evaluate the possibility to achieve a finer air/fuel ratio control during transients that involve sudden variations in the physical conditions inside the intake manifold, due, for example, to fast throttle opening or closing actions. The air mass flow rate toward the engine cylinders undertakes strong variation in such transients, and its correct estimation becomes critical mainly because of the time lag between its evaluation and the instant when the air actually enters the cylinders.

Combustion phasing is crucial to achieve high performance and efficiency: for gasoline engines control variables such as Spark Advance (SA), Air-to-Fuel Ratio (AFR), Variable Valve Timing (VVT), Exhaust Gas Recirculation (EGR), Tumble Flaps (TF) can influence the way heat is released. The optimal control setting can be chosen taking into account performance indicators, such as Indicated Mean Effective Pressure (IMEP), Brake Specific Fuel Consumption (BSFC), pollutant emissions, or other indexes inherent to reliability issues, such as exhaust gas temperature, or knock intensity. Given the high number of actuations, the calibration of control parameters is becoming challenging.

This paper describes the development of a mathematical model which allows the simulation of the Internal Combustion Engine (ICE), the transmission and the vehicle dynamics of a motor vehicle equipped with a Continuously Variable Transmission (CVT) system. The aim of this work is to realize a simulation tool that is able to evaluate the performance and the operating conditions of the ICE, once it is installed on a given vehicle. Since the simulation has to be run in real-time for Hardware In the Loop (HIL) applications, a zero-dimensional (filling and emptying) model is used for modeling the cylinder thermodynamics and the intake and exhaust manifolds. The combustion is modeled by means of single zone model, with the fuel burning rate described by Wiebe functions. The gas proprieties depend on temperature and chemical composition of the gas, which are evaluated at each crank-angle.

This paper describes the development of a control-oriented model that allows the simulation of the Internal Combustion Engine (ICE) thermodynamics, including pressure wave effects. One of the objectives of this work is to study the effects of a Variable Valve Timing (VVT) system on the behavior of a single-cylinder, four-stroke engine installed on a motor scooter. For a single cylinder engine running at relatively high engine speeds, the amount of air trapped into the cylinder strongly depends on intake pressure wave effects: it is essential, therefore, the development of a model that has the ability to resolve the wave-action phenomena, if successful simulation of the VVT system effects is to be performed.

One challenge for the development of commercial vehicles is the reduction of CO2 greenhouse, where hydrogen can help to reduce the fleet CO2. For instance, in Europe a drop in fleet consumption of 15% and 30% is set as target by the regulation until 2025 and 2030. Another challenge is EURO VII in EU or even already approved CARB HD Low NOx Regulation in USA, not only for Diesel but also for hydrogen combustion engines. In this study, first the requirements for the combustion and after-treatment system of a hydrogen engine are defined based on future emission regulations. The major advantages regarded to hydrogen combustion are due to the wide range of flammability and very high flame speed numbers compared to other fossil based fuels. Thus, it can be well used for lean burn combustion with much better fuel efficiency and very low NOx emissions with an ultra lean combustion. A comprehensive experimental investigation is performed on a HD 2 L single-cylinder engine.

Individual cylinder Air-to-Fuel Ratio (AFR) control has been proposed by many authors in recent years as a technique of controlling the AFR of the various cylinders individually, based on a single lambda measurement for each engine bank. Most of such works describe theoretical and experimental efforts to develop and identify an observer, able to estimate the AFR of each cylinder separately. In this paper, a simple individual cylinder AFR controller is described, based on the observation that any type of AFR disparity between the various cylinders is reflected in a specific harmonic content of the AFR signal spectrum. In particular, any type of AFR disparity will be reflected on a limited number of frequencies, or harmonics, multiple of the engine cycle frequency.

Electronic Throttle Control systems substitute the driver in commanding throttle position, with the driver acting on a potentiometer connected to the accelerator pedal. Such strategies allow precise control of air-fuel ratio and of other parameters, e.g. engine efficiency or vehicle driveability, but require detailed information about the engine operating conditions, in order to be implemented inside the Electronic Control Unit (ECU). In order to determine throttle position, an interpretation of the driver desire (revealed by the accelerator pedal position) is performed by the ECU. In our approach, such interpretation is carried out in terms of a torque request that can be appropriately addressed knowing the actual engine-vehicle operating conditions, which depend on the acting torques. Estimates of the torque due to in-cylinder pressure (indicated torque), as well as the torque required by the vehicle (load torque), must then be available to the control module.

This paper shows how Rapid Control Prototyping (RCP) and Computational Fluid Dynamics (CFD) techniques have been applied to design and implement an engine control system for a common rail diesel engine. The project aim is to setup a high performance engine in order to participate to the Italian Tractor Pulling Championship (Prostock category). The original engine is a John Deere 6081 Tier2 model, already equipped with a common rail system. Engine performance is substantially determined by the control system, which is in charge of limiting engine speed, boost pressure and Air to Fuel Ratio (AFR). Given that typically the information and equipment needed to change control parameters are not accessible to customers, the first step of the project has been to replace the original control system, while maintaining injectors and pumps. This solution can guarantee the best performance, but it requires time to design the new control system, both in terms of hardware and software.

Hydrogen engines offer the possibility of a carbon neutral transportation - a focal point of current propulsion development activities especially for EU and US future concepts. From today's point of view, hydrogen can play an important role in this regard as it is a carbon-free fuel, no CO2 emissions are produced during its combustion process. Besides, it can be well used for lean burn combustion leading to very low NOx emissions, a key benefit in combination with an optimized after-treatment system for future ultra-low NOx legislations of heavy-duty (HD) engines. Comprehensive investigations using experimental tests and model-based development approach are performed using a six cylinder HD hydrogen engine featuring PFI (port fuel injection) aiming the definition of a high efficiency hydrogen engine concept.

This paper presents the experimental work and the results obtained from the implementation of a transient fuel compensation algorithm for the 6.0-liter V12 high-performance engine that equips the Lamborghini Diablo vehicles. This activity has been carried out as part of an effort aimed at the optimization of the entire fuel injection control system. In the first part of the paper the tests for fuel film compensator identification are presented and discussed. In this phase the experimental work has been conducted in the test cell. An automatic calibration algorithm was developed to identify the well-known fuel film model X and τ parameters, so as to define their maps as a function of engine speed and intake manifold pressure. The influence of engine coolant temperature has been investigated separately; it will be soon presented together with the air dynamics compensation algorithm. In the second part of the paper, the performance of the fuel dynamics compensation algorithm is analyzed.

The most recent European regulations for two- and three-wheelers (Euro 5) are imposing an enhanced combustion control in motorcycle engines to respect tighter emission limits, and Air-Fuel Ratio (AFR) closed-loop control has become a key function of the engine management system also for this type of applications. In a multi-cylinder engine, typically only one oxygen sensor is installed on each bank, so that the mean AFR of two or more cylinders rather than the single cylinder one is actually controlled. The installation of one sensor per cylinder is normally avoided due to cost, layout and reliability issues. In the last years, several studies were presented to demonstrate the feasibility of an individual AFR controller based on a single sensor. These solutions are based on the mathematical modelling of the engine air path dynamics, or on the frequency analysis of the lambda probe signal.

Reduction of the CO2 greenhouse gas emissions is one major challenge the automotive industry as a part of the transportation sector is facing. Hydrogen is regarded as one of the key energy solutions for CO2 reduction in the future transportation sector. First, a hydrogen-powered single-cylinder test rig for 2 liter heavy-duty engine will be introduced. Followed by a discussion of experimental results including variations of engine speed, torque, ignition strategy, air-fuel ratio, etc. In addition, the paper proposes a new phenomenological model for the prediction of hydrogen combustion. The model is based on the well-known two-zone Entrainment approach, supported by newly developed hydrogen-specific submodels for the calculation of the laminar flame speed and auto-ignition in the unburned mass zone. The developed physical-based combustion model is extensively validated based on the experimental single-cylinder results.

This paper investigates an optimal design of a diesel engine and after-treatment systems for a series hybrid electric forklift application. A holistic modeling approach is developed in GT-Suite® to establish a model-based hardware definition for a diesel engine and an after-treatment system to accurately predict engine performance and emissions. The used engine model is validated with the experimental data. The engine design parameters including compression ratio, boost level, air-fuel ratio (AFR), injection timing, and injection pressure are optimized at a single operating point for the series hybrid electric vehicle, together with the performance of the after-treatment components. The engine and after-treatment models are then coupled with a series hybrid electric powertrain to evaluate the performance of the forklift in the standard VDI 2198 drive cycle.

In the past years, stringent emission regulations for Internal Combustion (IC) engines produced a large amount of research aimed at the development of innovative combustion methodologies suitable to simultaneously reduce fuel consumption and engine-out emissions. Previous research demonstrates that the goal can be obtained through the so-called Low Temperature Combustions (LTC), which combine the benefits of compression-ignited engines, such as high compression ratio and unthrottled lean operation, with a properly premixed air-fuel mixture, usually obtained injecting gasoline-like fuels with high volatility and longer ignition delay. Gasoline Partially Premixed Combustion (PPC) is a promising LTC technique, mainly characterized by the high-pressure direct-injection of gasoline and the spontaneous ignition of the premixed air-fuel mixture through compression, which showed a good potential for the simultaneous reduction of fuel consumption and emissions in CI engines.