The valorization of residual biomass plays today a decisive role in the concept of “circular econ... more The valorization of residual biomass plays today a decisive role in the concept of “circular economy”, according to which each waste material must be reused to its maximum extent. The collection and energy valorization at the local level of biomass from forest management practices and wildfire prevention cutting can be settled in protected areas to contribute to local decarbonization, by removing power generation from fossil fuels. Despite the evident advantages of bioenergy systems, several problems still hinder their diffusion, such as the need to assure their reliability by extending the operating range with materials of different origin. The Italian project “INNOVARE—Innovative plants for distributed poly-generation by residual biomass”, funded by the Italian Ministry of Economic Development (MISE), has the main scope of improving micro-cogeneration technologies fueled by biomass. A micro-combined heat and power (mCHP) unit was chosen as a case study to discuss pros and cons of ...
2018 IEEE International Conference on Environment and Electrical Engineering and 2018 IEEE Industrial and Commercial Power Systems Europe (EEEIC / I&CPS Europe), 2018
Engine idle stop-start (S&S) is a technology which allows a vehicle to automatically turn off... more Engine idle stop-start (S&S) is a technology which allows a vehicle to automatically turn off the internal combustion engine (ICE) when the vehicle has a rest and restarts the ICE when the driver applies pressure to the accelerator or releases the brake. Stop-Start system originated in Europe to save fuel during the type-approval New European Driving cycle (NEDC) because almost 25% of its driving time is in idling conditions. In real use, the largest benefits of S&S systems in vehicles result in urban areas where frequent stops are common. To evaluate the benefits of such systems in terms of fuel saving and emission reduction, an experimental campaign has been realized in Napoli. Three cars have been instrumented by using a Portable Emission System (PEMS) and driven along urban routes. Carbon dioxide (CO2), carbon monoxide (CO) and nitrogen oxides (NOX) have been evaluated for each trip in function of the average time spent stopping at traffic lights or for traffic conditions, as a percentage of a trip's duration.
Abstract Syngas deriving from biomass gasification is receiving increased interest as an alternat... more Abstract Syngas deriving from biomass gasification is receiving increased interest as an alternative fuel in spark ignition (SI) engines for power generation, despite problems related to the variability of its composition and the low energy density. Syngas release from gasifiers is indeed strongly affected by the quality of the feedstock and by the specific features and control strategy of the reactor. The paper considers the possibility to achieve, at the same time, high efficiency and low pollutant emissions of a syngas powered engine by acting on operating variables as the spark timing and the air-to-fuel ratio, with also the possible inclusion of exhaust gas recirculation (EGR). Model-based design and multi-objective optimization methods are applied as a feasible approach to address this issue, hence to improve the energetic and the environmental performances of power generation under a flexible fuel quality. A one-dimensional (1D) model of a naturally aspirated SI engine fuelled by syngas, properly developed and validated through a specific experimental campaign, is here presented to investigate the effect of the main controlling variables on power output and emissions. A proper design of experiment (DoE) space is considered. The 1D model is coupled with a genetic optimization algorithm for the search of the best compromise solution between maximum performance and minimum pollutants amount. The identified optimal solution allows a reduction up to the 50% for both nitrogen oxides and carbon monoxide emissions with a negligible worsening of the power output.
For the first time, catalytic conversion of CO2 to CH4 (Sabatier reaction) has been studied on re... more For the first time, catalytic conversion of CO2 to CH4 (Sabatier reaction) has been studied on real vehicle exhaust. Preliminary tests were carried out on model gas mixtures using as reactants a N2/CO2 gas mixture (CO2 = 9.5 vol% concentration similar to that of road vehicle exhaust) and pure hydrogen. Ruthenium powder (5 wt%) on alumina was used as catalyst, in a fixed bed cylindrical reactor. The operating conditions investigated are P = 1 atm, temperature in the range 160–320 °C, contact time 0.6–1.29 s, and H2/CO2 ratio 2.75–4.11. Experimental conditions were varied to study the effect of temperature, contact time, and H2/CO2 ratio on conversion, yield, and selectivity of the process. Once evaluated the performance of the catalytic process and identified the best operating conditions, real exhausts of a two-wheel motorcycle and a four-wheel gasoline vehicle were treated with the same experimental apparatus. Analyses of physical and chemical characterization of catalyst samples before and after the use were also performed. Results show that, even though best performances are generally obtained with model mixtures, high CO2 conversion together with high yield and selectivity in CH4 can be obtained with real vehicle exhausts too. Moreover, phenomena causing the deactivation of catalyst have not been observed. Results seem to indicate good opportunities for the development of the process.
Abstract: A reason of the lack of agreement between measured pollutants concentration in the air ... more Abstract: A reason of the lack of agreement between measured pollutants concentration in the air of urban areas and vehicle pollutant emissions evaluated by available emission models is the fact that catalyst performance variability is not considered. In this paper, an experimental study on the effect of performance variability of catalyst on emissions is presented. Average emissions have been measured using driving cycles representative of different levels of urban traffic, determined by statistical methods on the basis of data ...
ABSTRACT A wide investigation on powered two-wheelers (PTWs) is presented, aiming at the analysis... more ABSTRACT A wide investigation on powered two-wheelers (PTWs) is presented, aiming at the analysis of the influence of the driving characteristics on PTWs exhaust emissions and fuel consumption, a deeper comprehension of the engine and after-treatment system behavior within the cold start transient and the evaluation of cold start additional emissions for different two-wheelers classes. The study was developed with reference to an European context focusing on Euro 3 motorcycles and Euro 2 mopeds. An experimental investigation on instantaneous speed measurements was carried out with instrumented motorcycles, considering typical urban trips in the city of Genoa. A selection of speed profiles was then performed by processing experimental values. In a following phase, emissions and fuel consumption of selected motorcycles and mopeds were measured on the chassis dynamometer, considering tests in cold and hot operating conditions on standard, real world driving cycles and experimental speed profiles, allowing to study the influence of different speed patterns on exhaust emissions. Finally, a wide statistical analysis was developed in order to identify the most influencing kinematic parameters on fuel consumption and hot emissions, while analysis of cold start transient was conducted to assess the influence of vehicle characteristics and kinematic parameters of tested driving cycles on cold start duration, travelled length and extra-emissions. The main results of the wide investigation program are presented and discussed, with reference to Euro 3 scooters and Euro 2 mopeds with similar engine and after-treatment system characteristics, thus allowing a comparison between the different vehicle types.
Attention: This paper is not yet published. If you are interested in purchasing it - via Mail, Fa... more Attention: This paper is not yet published. If you are interested in purchasing it - via Mail, Fax or Download - please click on the "Mail" shopping cart icon below and proceed through the checkout process once you are finished browsing our web site. When this paper becomes ...
This paper deals with the possibility of improving the urea dosage control for the Selective Cata... more This paper deals with the possibility of improving the urea dosage control for the Selective Catalytic Reduction Systems (SCR) of an Euro VI d diesel light commercial vehicle in order to increase [Formula: see text] after-treatment reduction performance. To this aim, first, we assess the effective emissions abatement performance for the appraised diesel vehicle via real-world experimental campaign, carried out according to the Real Driving Emissions (RDE) tests on urban, extra-urban and motorway road sections in Naples, Italy. Based on these real-world data, we derive a parameterized control-oriented model for the SCR system which is, then, exploited for the designing of an alternative urea injection logic which could be able to maximize the [Formula: see text] reduction efficiency while minimizing tailpipe ammonia slip. Specifically, the optimal AdBlue injection rate is designed according to a Nonlinear Model Predictive Control Approach which allows obtaining a proper trade-off bet...
Abstract Mopeds are popular means of transportation, particularly in southern Europe and in easte... more Abstract Mopeds are popular means of transportation, particularly in southern Europe and in eastern and southern Asia. The relative importance of their emissions increases in urban environments which host large fleets of mopeds. In Naples, for example, mopeds make a considerable contribution to HC emissions (about 53%), although the percentage of mopeds (12.4%) in the total circulating fleet is lower than that of other vehicle categories [1].
The valorization of residual biomass plays today a decisive role in the concept of “circular econ... more The valorization of residual biomass plays today a decisive role in the concept of “circular economy”, according to which each waste material must be reused to its maximum extent. The collection and energy valorization at the local level of biomass from forest management practices and wildfire prevention cutting can be settled in protected areas to contribute to local decarbonization, by removing power generation from fossil fuels. Despite the evident advantages of bioenergy systems, several problems still hinder their diffusion, such as the need to assure their reliability by extending the operating range with materials of different origin. The Italian project “INNOVARE—Innovative plants for distributed poly-generation by residual biomass”, funded by the Italian Ministry of Economic Development (MISE), has the main scope of improving micro-cogeneration technologies fueled by biomass. A micro-combined heat and power (mCHP) unit was chosen as a case study to discuss pros and cons of ...
2018 IEEE International Conference on Environment and Electrical Engineering and 2018 IEEE Industrial and Commercial Power Systems Europe (EEEIC / I&CPS Europe), 2018
Engine idle stop-start (S&S) is a technology which allows a vehicle to automatically turn off... more Engine idle stop-start (S&S) is a technology which allows a vehicle to automatically turn off the internal combustion engine (ICE) when the vehicle has a rest and restarts the ICE when the driver applies pressure to the accelerator or releases the brake. Stop-Start system originated in Europe to save fuel during the type-approval New European Driving cycle (NEDC) because almost 25% of its driving time is in idling conditions. In real use, the largest benefits of S&S systems in vehicles result in urban areas where frequent stops are common. To evaluate the benefits of such systems in terms of fuel saving and emission reduction, an experimental campaign has been realized in Napoli. Three cars have been instrumented by using a Portable Emission System (PEMS) and driven along urban routes. Carbon dioxide (CO2), carbon monoxide (CO) and nitrogen oxides (NOX) have been evaluated for each trip in function of the average time spent stopping at traffic lights or for traffic conditions, as a percentage of a trip's duration.
Abstract Syngas deriving from biomass gasification is receiving increased interest as an alternat... more Abstract Syngas deriving from biomass gasification is receiving increased interest as an alternative fuel in spark ignition (SI) engines for power generation, despite problems related to the variability of its composition and the low energy density. Syngas release from gasifiers is indeed strongly affected by the quality of the feedstock and by the specific features and control strategy of the reactor. The paper considers the possibility to achieve, at the same time, high efficiency and low pollutant emissions of a syngas powered engine by acting on operating variables as the spark timing and the air-to-fuel ratio, with also the possible inclusion of exhaust gas recirculation (EGR). Model-based design and multi-objective optimization methods are applied as a feasible approach to address this issue, hence to improve the energetic and the environmental performances of power generation under a flexible fuel quality. A one-dimensional (1D) model of a naturally aspirated SI engine fuelled by syngas, properly developed and validated through a specific experimental campaign, is here presented to investigate the effect of the main controlling variables on power output and emissions. A proper design of experiment (DoE) space is considered. The 1D model is coupled with a genetic optimization algorithm for the search of the best compromise solution between maximum performance and minimum pollutants amount. The identified optimal solution allows a reduction up to the 50% for both nitrogen oxides and carbon monoxide emissions with a negligible worsening of the power output.
For the first time, catalytic conversion of CO2 to CH4 (Sabatier reaction) has been studied on re... more For the first time, catalytic conversion of CO2 to CH4 (Sabatier reaction) has been studied on real vehicle exhaust. Preliminary tests were carried out on model gas mixtures using as reactants a N2/CO2 gas mixture (CO2 = 9.5 vol% concentration similar to that of road vehicle exhaust) and pure hydrogen. Ruthenium powder (5 wt%) on alumina was used as catalyst, in a fixed bed cylindrical reactor. The operating conditions investigated are P = 1 atm, temperature in the range 160–320 °C, contact time 0.6–1.29 s, and H2/CO2 ratio 2.75–4.11. Experimental conditions were varied to study the effect of temperature, contact time, and H2/CO2 ratio on conversion, yield, and selectivity of the process. Once evaluated the performance of the catalytic process and identified the best operating conditions, real exhausts of a two-wheel motorcycle and a four-wheel gasoline vehicle were treated with the same experimental apparatus. Analyses of physical and chemical characterization of catalyst samples before and after the use were also performed. Results show that, even though best performances are generally obtained with model mixtures, high CO2 conversion together with high yield and selectivity in CH4 can be obtained with real vehicle exhausts too. Moreover, phenomena causing the deactivation of catalyst have not been observed. Results seem to indicate good opportunities for the development of the process.
Abstract: A reason of the lack of agreement between measured pollutants concentration in the air ... more Abstract: A reason of the lack of agreement between measured pollutants concentration in the air of urban areas and vehicle pollutant emissions evaluated by available emission models is the fact that catalyst performance variability is not considered. In this paper, an experimental study on the effect of performance variability of catalyst on emissions is presented. Average emissions have been measured using driving cycles representative of different levels of urban traffic, determined by statistical methods on the basis of data ...
ABSTRACT A wide investigation on powered two-wheelers (PTWs) is presented, aiming at the analysis... more ABSTRACT A wide investigation on powered two-wheelers (PTWs) is presented, aiming at the analysis of the influence of the driving characteristics on PTWs exhaust emissions and fuel consumption, a deeper comprehension of the engine and after-treatment system behavior within the cold start transient and the evaluation of cold start additional emissions for different two-wheelers classes. The study was developed with reference to an European context focusing on Euro 3 motorcycles and Euro 2 mopeds. An experimental investigation on instantaneous speed measurements was carried out with instrumented motorcycles, considering typical urban trips in the city of Genoa. A selection of speed profiles was then performed by processing experimental values. In a following phase, emissions and fuel consumption of selected motorcycles and mopeds were measured on the chassis dynamometer, considering tests in cold and hot operating conditions on standard, real world driving cycles and experimental speed profiles, allowing to study the influence of different speed patterns on exhaust emissions. Finally, a wide statistical analysis was developed in order to identify the most influencing kinematic parameters on fuel consumption and hot emissions, while analysis of cold start transient was conducted to assess the influence of vehicle characteristics and kinematic parameters of tested driving cycles on cold start duration, travelled length and extra-emissions. The main results of the wide investigation program are presented and discussed, with reference to Euro 3 scooters and Euro 2 mopeds with similar engine and after-treatment system characteristics, thus allowing a comparison between the different vehicle types.
Attention: This paper is not yet published. If you are interested in purchasing it - via Mail, Fa... more Attention: This paper is not yet published. If you are interested in purchasing it - via Mail, Fax or Download - please click on the "Mail" shopping cart icon below and proceed through the checkout process once you are finished browsing our web site. When this paper becomes ...
This paper deals with the possibility of improving the urea dosage control for the Selective Cata... more This paper deals with the possibility of improving the urea dosage control for the Selective Catalytic Reduction Systems (SCR) of an Euro VI d diesel light commercial vehicle in order to increase [Formula: see text] after-treatment reduction performance. To this aim, first, we assess the effective emissions abatement performance for the appraised diesel vehicle via real-world experimental campaign, carried out according to the Real Driving Emissions (RDE) tests on urban, extra-urban and motorway road sections in Naples, Italy. Based on these real-world data, we derive a parameterized control-oriented model for the SCR system which is, then, exploited for the designing of an alternative urea injection logic which could be able to maximize the [Formula: see text] reduction efficiency while minimizing tailpipe ammonia slip. Specifically, the optimal AdBlue injection rate is designed according to a Nonlinear Model Predictive Control Approach which allows obtaining a proper trade-off bet...
Abstract Mopeds are popular means of transportation, particularly in southern Europe and in easte... more Abstract Mopeds are popular means of transportation, particularly in southern Europe and in eastern and southern Asia. The relative importance of their emissions increases in urban environments which host large fleets of mopeds. In Naples, for example, mopeds make a considerable contribution to HC emissions (about 53%), although the percentage of mopeds (12.4%) in the total circulating fleet is lower than that of other vehicle categories [1].
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Papers by Maria Vittoria Prati