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In this paper, we propose a novel control architecture for dealing with the requirements arising in a cooling system of an ICE. The idea is to take advantage of the joint action of an electric pump and of an ad-hoc regulation module, which is used to determine adequate flow rates despite engine speeds. Specifically, a robust Model Predictive Control approach is exploited to take care formally of input/output constraints and disturbance effects of the resulting lumped parameter model of the engine cooling system, which incorporates the nucleate boiling heat transfer regime. Numerical simulations and test rig experimental data are presented. The results achieved show that the proposed control scheme is capable of providing effective and safe cooling while mitigating disturbance effects and minimizing coolant flow rates when compared with the action pertaining to standard crankshaft driven pumps.

The aim of the present work is to analyse and compare the energetic performances and the emissions conversion capability of active and passive aftertreatment systems for lean burn engines. To this purpose, a computational one-dimensional transient model has been developed and validated. The code permits to assess the heat exchange between the solid and the exhaust gas, to evaluate the conversion of the main engine pollutants, and to estimate the energy effectiveness. The response of the systems to variations in engine operating conditions have been investigated considering standard emission test cycles. The analysis highlighted that the active flow control tends to increase the thermal inertia of the apparatus and then it appears more suitable to maintain higher temperature level and to guarantee higher pollutants conversion at low engine loads after long full load operation.

The present study aims at analyzing the flow field within a Lean NOx Trap (LNT). To this purpose a twofold approach based on the synergic use of numerical and non-intrusive experimental techniques was adopted. The measurements were carried out at a steady flow rig in terms of global performances and local velocity measurements. In particular, mass flow rates and pressure drops were used to define the global fluid dynamic efficiency of the system, while the Laser Doppler Anemometry (LDA) technique was employed to determine the flow field within the aftertreatment apparatus. At the same time, a finite volume CFD code was adopted for the numerical analysis. The comparison between experimental and numerical data displayed a good agreement in terms of global and local quantities. Specifically, the numerical code well-reproduced the main structure within the emission control system.

In this work, a dynamic 0-D electro-thermal model of a lithium-polymer battery for automotive applications is presented. The model predicts the battery temperature during its charging/discharging phases under different environmental and operating conditions, by considering the requested power or current, the coolant flow rate and its temperature as model inputs. The model was first validated with experimental data carried out at the test bench where only the convective heat transfer between the battery and the ambient air was considered. The accuracy of the internal heat generation model was experimentally assessed for different current discharge rates. Then, a liquid cooling system was designed on purpose, assembled, and installed on the battery at the test bench for the improvement of the model predictions in liquid convection conditions.

The road transportation sector is undergoing significant changes, and new green scenarios for sustainable mobility are being proposed. In this context, a diversification of the vehicles’ propulsion, based on electric powertrains and/or alternative fuels and technological improvements of the electric vehicles charging stations, are necessary to reduce greenhouse gas emissions. The adoption of internal combustion engines operating with alternative fuels, like methanol, may represent a viable solution for overcoming the limitations of actual grid connected charging infrastructure, giving the possibility to realize off-grid charging stations. This work aims, therefore, at investigating this last aspect, by evaluating the performance of an internal combustion engine fueled with methanol for stationary applications, in order to fulfill the potential demand of an on off-grid charging station.

This work is developed in the framework of an industrial R&D project, titled ARIA (Active Responsive Intelligent Aerodynamics), having the main goal to improve the efficiency of a vehicle by introducing active aerodynamics supported by innovative actuation systems. The work focuses on the development of a new aesthetic Active Grille Shutter (AGS), which, differently from the currently marketed vehicles, does not include the presence of a grille in front of it. In addition, an innovative actuation system, based on the adoption of Shape Memory Alloys (SMA) is being investigated for the new AGS, with the main goal to exploit the advantages arising in terms of increased efficiency coupled with a marked weigh reduction. The proposed analysis aims, at first, at evaluating the effects of different AGS configurations on the drag coefficient, Cx, of the vehicle and on the related benefits.