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Diesel engine exhausts from a common rail 3.0 L F1C diesel engine were analyzed at two different load conditions of the WLTC testing cycle downstream of both the diesel particulate filter (DPF) and selective catalytic reactor (SCR) to verify their effect on the characteristics of carbon particulate matter. An array of chemical, physical and spectroscopic techniques (gas chromatography coupled with mass spectrometry (GC-MS), mobility analyzer, UV-Visible absorption and fluorescence spectroscopy) was applied for characterizing polycyclic aromatic hydrocarbons (PAH), heavy aromatic compounds and soot, constituting the particulate matter (PM) sampled from the exhaust. The engine was operated in half load (HL) (188 Nm, representing the more common condition for engine in urban traffic) and full load (FL) (452 Nm, representing the best performance of the engine operation) conditions, at the same engine speed (2000 rpm). Soot formation was enhanced in HL condition, with respect to FL, but, just because of the much lower soot amount, the after-treatment systems in this last condition resulted to be less efficient in the soot abatement. Indeed, the abatement through DPF was about 40% lower in the FL condition with respect to HL condition, and any significant further concentration decrease was found after SCR, in both conditions. By contrast, PAH concentration after DPF abatement was found to be higher in the HL with respect to FL condition. A further PAH concentration decrease of about 30% was found after the SCR in the HL condition whereas in FL the reduction was only about 5-6%. Also the heavy aromatic compounds having molecular weight above the GC-MS detection limit (300 u), were mitigated by SCR. Therefore, SCR did not cause a further soot reduction, whereas it was effective in largely reducing PAH and heavy aromatics emissions, especially in the lower temperature condition featuring the half-load condition, when combustion efficiency is worse. Moreover, SCR system reduced the emission of small particles probably due to an enhanced agglomeration of particles, with beneficial effect on the harmfulness to human health.

Capítulos en libros This paper describes a strategic information platform developed for the German electric utility Eon, to provide historical bidding analysis and medium-term forecasting of the Iberian Electricity Market. This platform, PLAMER, has three main modules: Initialization module, consisting of different sub-modules to define the electrical system structure and to organize the input data of the rest of modules, PLAMER-bids, to read, aggregate and visualize market historical bids and also to prepare them for their future forecasted values, and PLAMER-clearing, for market clearing emulation using forecasted bids. PLAMER-clearing models the Iberian market based on a bid clearing mechanism with an inherent market splitting procedure. This market splitting is built with a bi-nodal simplification, one node representing the Spanish System and the other the Portuguese one. Both are simply connected by a unique equivalent interconnection line. The medium term clearing model uses a generation portfolio per generation company in terms of technologies, for supplying monthly demand for different load levels, and labour and non-labour periods. Some technical constraints, such as minimum outputs and pumping energy balance, are also taking into account. The mathematical problem of PLAMER-clearing is a quadratic programming model solved using GAMS language and CPLEX optimizer. Finally, a real Iberian case study is detailed and some market splitting outputs are analyzed. info:eu-repo/semantics/publishedVersion

Originally developed and validated at the Cabauw (Netherlands) topographically flat onshore location, the alpha-I wind resource extrapolating method was tested at the FINO3 offshore site in the North Sea (Germany). The aim was to prove its validity also when applied over a substantially different environment in terms of surface characteristics and stability conditions. Data from local mast at 30, 80, and 100 m were used, with extrapolations to 80-m and 100-m turbine hub heights accomplished based on 30-m turbulence intensity observations. Trained over a 2-year period (2011-2012), the method was validated on year 2013. Similarly to the onshore application, the method was reliable in extrapolating wind speed to both 80 m and 100 m, with bias within 5%, NRMSE = 0.20 and r = 0.94. Conversely, scores were largely better than at the onshore site in predicting the annual energy yield, biased by 0.41-1.02% at 80 m, and 1.12-1.36% at 100 m. The method proved to be highly sensitive to the stability classification, as not considering this option increased its biases to 4.51-5.93% at 80 m, and 7.46-8.23% at 100 m. Method's reliability might suitably help reduce the number of masts installed throughout a large offshore area.

The modern Common Rail Diesel engine are, normally, optimised for being fuelled with the commercial Diesel fuel. The ECU calibrations are, consequently, defined to obtain the correct compromise between performances and emissions. It is, so, clear that if the engine is fuelled with an alternative bio-fuel with different characteristics (net heating value, stoichiometric A/F ratio, density, viscosity, etc.) the calibration must be modify. Interest in fuels from renewable sources and their use in transport has grown over the last decade. This is because of their biodegradability, potential improvements in exhaust emissions and benefits on the virtuous CO2 cycle of the earth. This paper demonstrates that it is possible to optimise the emissions and the performances of a light duty diesel C.R. engine fuelled with a vegetable derived fuel (Rapeseed Methyl-Ester) pure or blended with commercial Diesel fuel. Particularly in this paper the experimental results and the ECU control solutions referring to different fuel compositions are shown.

This paper is focused on the measurement issues and procedures for the characterization of medium voltage grids for narrowband power line communications (NB-PLCs), in the perspective of the use and integration of such technology into smart grids communication networks. The fundamentals are given for the characterization of the PLC channel, by means of noise and attenuation measurements. Suitable procedures are also developed for the characterization and modeling of the power system components in the frequency range of interest. Furthermore, the complete model of the PLC system is experimentally validated in a real case study.

In this paper some preliminary experimental results on a Zebra battery based propulsion system for urban bus applications are presented. The tests were carried out using a laboratory 1:1 scale test bench, composed by a 65 kW electric drive, specifically designed for urban bus applications, supplied by two 20 kWh Zebra batteries connected in parallel. The electric power train was tested on a laboratory bench, connected through a fixed ratio gear box to a 100 kW regenerative electric brake provided with speed and torque controls, in order to evaluate the propulsion system performance in steady state operative conditions. The obtained preliminary experimental results were utilized to implement a Matlab-Simulink model of urban bus, which might be powered by the same electric propulsion system studied. Thanks to this model it was possible to evaluate the dynamic behavior of the urban bus, working on standard driving cycles, taking into account the resistant forces represented by proper vehicle/road/aerodynamic parameters. An evaluation of the expected real vehicle driving range was also estimated in different road conditions.

This paper aims to correlate the in-cylinder soot formation and the exhaust particle emissions for different methods of gasoline/ethanol fueling in spark ignition engine. In particular, the engine was fueled with gasoline and ethanol separately and not, in this latter case both blended (E30) and dual fueled (EDF). For E30 the bend was direct injected and for EDF, the ethanol was injected in the combustion chamber and the gasoline into the intake duct. For both the injection configurations, the same percentage of ethanol in gasoline was supplied: 30%v/v. The measurements were carried out at 2000 and 4000 rpm, under full load, and stoichiometric condition, in small single cylinder optical engine. 2D-digital imaging was performed to follow the combustion process with a high spatial and temporal resolution through a full-bore optical piston. The two-color pyrometry was applied for the analysis of the in cylinder soot formation in the combustion chamber. Particle mass concentration was evaluated at the exhaust by means of a smoke meter. The particle size distribution function was measured in the range from 5.6 to 560 nm by an Engine Exhaust Particle Sizer (EEPS). It was observed that the use of ethanol allows the reduction of soot formation and particles emission in DI configuration. However, for E30 the in-cylinder soot formation and emissions are larger than EDF. This result is mainly due to the different contribution of gasoline. Optical analysis shows that in E30 the direct injected gasoline causes wide diffusive flames where soot formation is promoted; whereas for EDF the better evaporation and mixing of gasoline, typical of PFI configuration, results in few, small, and localized diffusive flames producing smaller particle emissions.

The use of methane as supplement to liquid fuel is one of the solution proposed for the reduction of the internal combustion engine pollutant emissions. Its intrinsic properties as the high knocking resistance and the low carbon content makes methane the most promising clean fuel. The dual fuel combustion mode allows improving the methane combustion acting mainly on the methane slow burning velocity and allowing lean burn combustion mode. An experimental investigation was carried out to study the methane-gasoline dual fuel combustion. Methane was injected in combustion chamber (DI fuel) while gasoline was injected in the intake manifold (PFI fuel). The measurements were carried out in an optically accessible small single-cylinder four-stroke engine. It was equipped with the cylinder head of a commercial 250 cc motorcycles engine representative of the most popular two-wheel vehicles in Europe. UV-visible spectroscopy measurements were performed to analyze the combustion process with high spatial and temporal resolution. In particular, UV-visible spectroscopy allows detecting the chemical markers of combustion process such as the radicals OH* and CH*. The in-cylinder lambda spatial and temporal evolution was evaluated. The combustion evolution is characterized by means of a high speed cycle resolved camera. The exhaust emissions were characterized by means of gaseous analyzers. The measurements were performed under steady state conditions at different engine operating conditions.

A new concept of a system for Combined Heat and Power generation is presented. The concept is based on hybrid use of two renewable energy sources, direct solar (thermodynamic solar) and biomass (indirect solar energy). Biomass combustion is conducted using a fluidized bed combustor. A second source of energy, given by the direct irradiation of the bed with a concentrated solar radiation, is integrated in the same system, using the fluidized bed as solar receiver. A Stirling engine converts heat into mechanical power. A Scheffler type mirror is adopted to allow irradiation of the system in a fixed focal point. Advantages of the proposed solution are illustrated and some preliminary results on the performance of the system, obtained with a simple model, are presented. The principal improvements with respect to existing systems of similar size and primary energy source are illustrated. The most important are the enhanced heat transfer processes that are realized with the help of the fluidized bed, and the possibility of continuous cogeneration during the day. Different working conditions are considered to estimate the contribution given by the burning of fuel, in presence as well as in absence of sun irradiation (as during the night). The distribution of energy shares among the different flux contributes is reported versus the amount of biomass burned per unit time. The results clearly demonstrate the advantage of coupling, in the same system, two sources for heat generation, thus maintaining the option of producing electricity without the supply of biomass fuel.