Luigi De Simio - Academia.edu (original) (raw)
Papers by Luigi De Simio
Processes
LNG technologies have long been used but only recently found widespread employment on medium and ... more LNG technologies have long been used but only recently found widespread employment on medium and small scales compared to the traditional cycle of liquefaction, transport by ship, regasification and injection into the gas network. This has increased the direct use of LNG with the problem of limiting greenhouse gas emissions, linked to gas released principally in the event of prolonged absence of fuel drawing from the cryogenic tank. This study analyzes the energetic exploitation of BOG in small internal combustion engines. The effect on CO2 equivalent emissions was evaluated, making a comparison with the BOG emission into the atmosphere directly or after burning. A 1 kW gasoline engine was selected for a 500-litre LNG tank and converted to gas fueling. The measured consumption and emissions resulted in compliance with a lower environmental impact compared to direct BOG release into the atmosphere despite simplified technical solutions, such a cheap and light 2-stroke engine. In cont...
The Global Environmental Engineers
The urgent need to reduce greenhouse gas emissions by gradually abandoning fossil fuel sources is... more The urgent need to reduce greenhouse gas emissions by gradually abandoning fossil fuel sources is required due to climate-changing emergencies. Employing as much as possible renewable energy, in any form and any field, together with a reduction of per capita energy need, can reduce this tendency and contrast the catastrophic consequence of our planet temperature increasing. In this scenario, biofuels production, together with reuse and recycling represent a correct strategy to contrast environmental degradation. Biofuel has been the subject of great interest over the past decade. Their development from the first to the fourth generation has led to significant improvements in the production cycles and extended the interest in new resources. The availability of different choices could permit to use always the best solution to maximize the result. In this paper, the different biofuel generations are presented with the aim of highlighting strengths and weaknesses to identify a smart app...
The exhaust gas recirculation can be used in a stoichiometric engine, for suppressing knocking an... more The exhaust gas recirculation can be used in a stoichiometric engine, for suppressing knocking and increasing efficiency, without a significant impact on pollutant emissions, since charge dilution is obtained with inert gases, allowing closed-loop control operations. However, relatively high EGR rates make worse the combustion process. This chapter deepens the effects of EGR on the performance of gaseous powered engines. In particular, the experimental data have been obtained fueling two engines with NG and NG/H2 mixtures until 40% by volume of hydrogen, at steady state for different loads, measuring emissions upstream and downstream the three-way catalyst and analyzing the combustion process. A naturally aspirated light-duty spark ignition engine and a turbocharged heavy-duty one were tested. The results obtained with the two engines were consistent with each other. In particular, EGR could be utilized to have high specific power, with reduced thermal stress, but also to increase e...
International Journal of Engine Research
An original method for formulating surrogate fuels from actual syngas mixtures is presented and f... more An original method for formulating surrogate fuels from actual syngas mixtures is presented and formalised. The method is the first example in the scientific literature of a rather complete tool for planning and setting up a laboratory syngas-fuelled engine test when some components of the syngas mixture are not available. Basically, the method allows a map to be built that provides the composition for a surrogate fuel once the composition of a syngas mixture is assigned, the components of a surrogate fuel are selected and the equivalence parameters are defined. The laminar flame speed, the energy density of the fuel–air mixture and the methane number are identified as equivalence parameters in the study. In particular, the proper laminar flame speed and energy density ensure that an engine fuelled by the surrogate mixture produces the same indicated power as it would when fuelled by the original syngas. Instead, the methane number allows for checking the fact that the tendency of t...
SAE Technical Paper Series
SAE Technical Paper Series
SAE Technical Paper Series
Green Energy and Technology, 2015
SAE Technical Paper Series, 2015
ISRN Renewable Energy, 2012
The use of bioethanol in the transport sector can contribute to mitigate the greenhouse gas emiss... more The use of bioethanol in the transport sector can contribute to mitigate the greenhouse gas emissions of the vehicles. To achieve this goal, together with a positive energy balance in global productive process of ethanol (well to tank), it is important that adding ethanol to gasoline does not cause a worsening of the efficiency of the internal combustion engine (tank to wheel). In this paper, a research activity on a commercial spark-ignition light-duty engine at the test bench is reported. The aim of the work was to characterize the effect of different bioethanol/gasoline blends on engine behaviour. Blends until 85% of ethanol were tested. Comparative studies of combustion development of gasoline and gasoline/ethanol blends at different concentrations have been made through the analysis of pressure cycles in combustion chamber. Moreover, emissions were collected and analyzed. Emissions downstream of the catalyst, measured with the blends, resulted quite similarly to the gasoline ca...
SAE Technical Paper Series, 2013
SAE Technical Paper Series, 2011
SAE Technical Paper Series, 2011
SAE Technical Paper Series, 2013
International Journal of Hydrogen Energy, 2013
ABSTRACT Hydrogen added to natural gas improves the process of combustion with the possibility to... more ABSTRACT Hydrogen added to natural gas improves the process of combustion with the possibility to develop engines with higher performance and lower environmental impact. In this paper experimental and numerical analyses on a multi cylinder stoichiometric heavy duty engine, fuelled with natural gas–hydrogen blends, are reported. Some constrains on hydrogen content and maximum load achievable have limited the scope of investigation. A specific modelling of the reference engine was developed to extend the study at full load condition and at higher hydrogen content. The results showed a higher combustion speed when hydrogen content in the fuel is increased. However, the positive effect of shorter combustion duration on thermal efficiency is mitigated by higher wall heat loss, due to higher combustion temperatures. Therefore lower CO2 emissions are due only to the substitution of natural gas with hydrogen, making crucial the way of hydrogen producing to have a benefit on well-to-wheel CO2 emissions.
Processes
LNG technologies have long been used but only recently found widespread employment on medium and ... more LNG technologies have long been used but only recently found widespread employment on medium and small scales compared to the traditional cycle of liquefaction, transport by ship, regasification and injection into the gas network. This has increased the direct use of LNG with the problem of limiting greenhouse gas emissions, linked to gas released principally in the event of prolonged absence of fuel drawing from the cryogenic tank. This study analyzes the energetic exploitation of BOG in small internal combustion engines. The effect on CO2 equivalent emissions was evaluated, making a comparison with the BOG emission into the atmosphere directly or after burning. A 1 kW gasoline engine was selected for a 500-litre LNG tank and converted to gas fueling. The measured consumption and emissions resulted in compliance with a lower environmental impact compared to direct BOG release into the atmosphere despite simplified technical solutions, such a cheap and light 2-stroke engine. In cont...
The Global Environmental Engineers
The urgent need to reduce greenhouse gas emissions by gradually abandoning fossil fuel sources is... more The urgent need to reduce greenhouse gas emissions by gradually abandoning fossil fuel sources is required due to climate-changing emergencies. Employing as much as possible renewable energy, in any form and any field, together with a reduction of per capita energy need, can reduce this tendency and contrast the catastrophic consequence of our planet temperature increasing. In this scenario, biofuels production, together with reuse and recycling represent a correct strategy to contrast environmental degradation. Biofuel has been the subject of great interest over the past decade. Their development from the first to the fourth generation has led to significant improvements in the production cycles and extended the interest in new resources. The availability of different choices could permit to use always the best solution to maximize the result. In this paper, the different biofuel generations are presented with the aim of highlighting strengths and weaknesses to identify a smart app...
The exhaust gas recirculation can be used in a stoichiometric engine, for suppressing knocking an... more The exhaust gas recirculation can be used in a stoichiometric engine, for suppressing knocking and increasing efficiency, without a significant impact on pollutant emissions, since charge dilution is obtained with inert gases, allowing closed-loop control operations. However, relatively high EGR rates make worse the combustion process. This chapter deepens the effects of EGR on the performance of gaseous powered engines. In particular, the experimental data have been obtained fueling two engines with NG and NG/H2 mixtures until 40% by volume of hydrogen, at steady state for different loads, measuring emissions upstream and downstream the three-way catalyst and analyzing the combustion process. A naturally aspirated light-duty spark ignition engine and a turbocharged heavy-duty one were tested. The results obtained with the two engines were consistent with each other. In particular, EGR could be utilized to have high specific power, with reduced thermal stress, but also to increase e...
International Journal of Engine Research
An original method for formulating surrogate fuels from actual syngas mixtures is presented and f... more An original method for formulating surrogate fuels from actual syngas mixtures is presented and formalised. The method is the first example in the scientific literature of a rather complete tool for planning and setting up a laboratory syngas-fuelled engine test when some components of the syngas mixture are not available. Basically, the method allows a map to be built that provides the composition for a surrogate fuel once the composition of a syngas mixture is assigned, the components of a surrogate fuel are selected and the equivalence parameters are defined. The laminar flame speed, the energy density of the fuel–air mixture and the methane number are identified as equivalence parameters in the study. In particular, the proper laminar flame speed and energy density ensure that an engine fuelled by the surrogate mixture produces the same indicated power as it would when fuelled by the original syngas. Instead, the methane number allows for checking the fact that the tendency of t...
SAE Technical Paper Series
SAE Technical Paper Series
SAE Technical Paper Series
Green Energy and Technology, 2015
SAE Technical Paper Series, 2015
ISRN Renewable Energy, 2012
The use of bioethanol in the transport sector can contribute to mitigate the greenhouse gas emiss... more The use of bioethanol in the transport sector can contribute to mitigate the greenhouse gas emissions of the vehicles. To achieve this goal, together with a positive energy balance in global productive process of ethanol (well to tank), it is important that adding ethanol to gasoline does not cause a worsening of the efficiency of the internal combustion engine (tank to wheel). In this paper, a research activity on a commercial spark-ignition light-duty engine at the test bench is reported. The aim of the work was to characterize the effect of different bioethanol/gasoline blends on engine behaviour. Blends until 85% of ethanol were tested. Comparative studies of combustion development of gasoline and gasoline/ethanol blends at different concentrations have been made through the analysis of pressure cycles in combustion chamber. Moreover, emissions were collected and analyzed. Emissions downstream of the catalyst, measured with the blends, resulted quite similarly to the gasoline ca...
SAE Technical Paper Series, 2013
SAE Technical Paper Series, 2011
SAE Technical Paper Series, 2011
SAE Technical Paper Series, 2013
International Journal of Hydrogen Energy, 2013
ABSTRACT Hydrogen added to natural gas improves the process of combustion with the possibility to... more ABSTRACT Hydrogen added to natural gas improves the process of combustion with the possibility to develop engines with higher performance and lower environmental impact. In this paper experimental and numerical analyses on a multi cylinder stoichiometric heavy duty engine, fuelled with natural gas–hydrogen blends, are reported. Some constrains on hydrogen content and maximum load achievable have limited the scope of investigation. A specific modelling of the reference engine was developed to extend the study at full load condition and at higher hydrogen content. The results showed a higher combustion speed when hydrogen content in the fuel is increased. However, the positive effect of shorter combustion duration on thermal efficiency is mitigated by higher wall heat loss, due to higher combustion temperatures. Therefore lower CO2 emissions are due only to the substitution of natural gas with hydrogen, making crucial the way of hydrogen producing to have a benefit on well-to-wheel CO2 emissions.