Luca Marchitto

• Mechanical engineering
• Researcher at Italian National Research Council

Shipping is a highly energy-intensive sector, and fleet decarbonization initiatives can significantly reduce greenhouse gas emissions. In the short-to-medium term, internal combustion engines will continue to be used for propulsion or as electricity generators onboard ships. Natural gas is an effective solution which can be used to mitigate greenho...

As part of the Zero Pollution Action Plan of the Green Deal, the European Commission has set the goal of reducing the number of premature deaths caused by fine particulate matter (PM2.5) by at least 55% by 2030, compared to 2005 levels. To achieve this, the European Commission aims to introduce stricter limits. In urban areas, road transport is a s...

Phased injection of natural gas into internal combustion marine engines is a promising solution for optimizing performance and reducing harmful emissions, particularly unburned methane, a potent greenhouse gas. This innovative practice distinguishes itself from continuous injection because it allows for more precise control of the combustion proces...

The transportation sector is responsible for about 16% of worldwide greenhouse gas emissions. Despite efforts for a sensible reduction by means of new technologies’ development, the average age of a vehicle fleet is 12.3 years in the European Union. In light of this, actions aiming at improving the efficiency of circulating vehicles can prove effec...

Phased injection of natural gas into internal combustion marine engines is a promising solution for optimizing performance and reducing harmful emissions, particularly unburned methane, a potent greenhouse gas. This innovative practice distinguishes itself from continuous injection because it allows for more precise control of the combustion proces...

This work presents the experimental results of a fluid dynamic investigation to characterize the injection of supercritical water in the combustion chamber of an internal combustion engine. Particle Image Velocimetry (PIV) analysis is carried out in an optically accessible 2-stroke Diesel engine. A prechamber, equipped with two optical accesses is...

div class="section abstract"> The need for a quick reduction in greenhouse gasses and noxious emissions is pushing maritime transportation to increase the use of alternative fuels. Natural Gas (NG) is well recognized as an effective solution to limit the use of marine diesel oil in the short/mid-term. In this scenario, dual-fuel technology is used...

div class="section abstract"> The transport of goods and people by sea, today, must meet the need to reduce the consumption of fuel oil. In addition, it has to ensure operational reliability and vessel availability, to reduce maintenance costs and comply with emission legislation. To this end, it is necessary to apply a marine engine combustion con...

This work deals with the effects of port water injection (WI) on torque and fuel consumption improvements of a port gasoline injection (PFI) boosted Spark Ignition engine. First, an experimental investigation is carried out at high loads and various speeds to acquire performance and combustion data under WI operation. The engine is fully schematize...

Ammonia (NH3) is among the largest-volume chemicals produced and distributed in the world and is mainly known for its use as a fertilizer in the agricultural sector. In recent years, it has sparked interest in the possibility of working as a high-quality energy carrier and as a carbon-free fuel in internal combustion engines (ICEs). This review aim...

In this work, the effects of in-cylinder heat transfer on indicated thermal efficiency of a spark ignition engine showing a cylinder-to-cylinder variation are numerically analyzed. A 1D CFD model of engine is developed and integrated with a turbulent combustion sub-model and with a refined thermal sub-model for cylinders and exhaust pipes. The mode...

Design trend in spark ignition (SI) engines aims to improve power density and efficiency to ensure that regulated emissions levels are minimized. From a thermodynamic point of view this involves increased in-cylinder pressure and local mixture conditions that promote autoignition of the end gas, leading to knock. In order to prevent knock, the comm...

Even in a scenario where electric vehicles gain market share and the sale of internal combustion engines is gradually reduced, at the present time, there are still no real options that can totally replace the internal combustion (IC) engine over the entire range of its applications [...]

This paper presents an experimental study investigating the effects of water-in-gasoline emulsion (WiGE) on the performance and emissions of a turbocharged PFI spark-ignition engine. The emulsions were produced through a micro-channels emulsifier, potentially capable to work inline, without addition of surfactants. Measurements were performed at a...

Combustion stability, engine efficiency and emissions in a multi-cylinder spark-ignition internal combustion engines can be improved through the advanced control and optimization of individual cylinder operation. In this work, experimental and numerical analyses were carried out on a twin-cylinder turbocharged port fuel injection (PFI) spark-igniti...

A combined experimental and numerical characterization of a Compression Ignition (CI) engine is here presented under Diesel and Waste Vegetable Oil (WVO) fueling at different loads. Main objective is to prove the feasibility of preheated WVO as substitute of Diesel fuel in CI engine for cogeneration purposes without modifying the engine geometry....

Stringent exhaust emission and fuel consumption regulations impose the need for new solutions for further development of internal combustion engines. With this in mind, a refined control of the combustion process in each cylinder can represent a useful and affordable way to limit cycle-to-cycle and cylinder-to-cylinder variation reducing CO2 emissi...

This paper deals with the effects of hydrogen port injection on combustion evolution, efficiency and exhaust emissions of a small turbocharged gasoline Spark-Ignition engine through a 1D numerical code. First, the experiments on the base engine architecture are performed at different speeds and at low/medium loads. The experimental findings are use...

L'iniezione di acqua rappresenta una tecnologia promettente per migliorare le prestazioni dei motori ad accensione comandata sovralimentati ad elevata potenza specifica. Questa soluzione consente, infatti, di lavorare con più alti rapporti di compressione, maggiore pressione di sovralimentazione e combustione stechiometrica ad alti carichi: ciò com...

This paper deals with the effects of hydrogen port injection on combustion evolution, efficiency and exhaust emissions of a small turbocharged gasoline Spark-Ignition engine through a 1D numerical code. First, the experiments on the base engine architecture are performed at different speeds and at low/medium loads. The experimental findings are use...

The stringent worldwide exhaust emission legislations for CO2 and pollutants require significant efforts to increase both the combustion efficiency and the emission quality of internal combustion engines. With this aim, several solutions are continuously developed to improve the combustion efficiency of spark ignition engines. Among the various sol...

This study examines the effects of ethanol and gasoline injection mode on the combustion performance and exhaust emissions of a twin cylinder port fuel injection (PFI) spark ignition (SI) engine. Generally, when using gasoline–ethanol blends, alcohol and gasoline are externally mixed with a specified blending ratio. In this activity, ethanol and ga...

Cooled exhaust gas recirculation (EGR) is a viable technique to mitigate the knock occurrence, to improve the fuel consumption and to reduce the nitrogen oxides (NOx) emissions of spark-ignition engines. This work aims at investigating the effects of a low-pressure cooled EGR system on the performance and exhaust emissions of a small-size turbochar...

Water in diesel emulsion (WiDE) is a viable solution for lowering both NOx and Soot emissions from compression ignition (CI) engines. In this paper, the effect of WiDE on the combustion process and exhaust emissions of a prototype optically accessible CI engine was investigated through conventional in-cylinder pressure measurements and optical diag...

Water injection represents a promising technology to overcome limitations of knock occurrence and fuel enrichment that reduce the efficiency of downsized spark-ignition (SI) engines. This paper presents the results of an experimental investigation performed on a port-fuel injection turbocharged spark-ignition engine within the speed range 3,000-4,5...

Cooled Exhaust Gas Recirculation (EGR) is a viable technique to mitigate the knock tendency and to improve the fuel consumption of Spark-Ignition (SI) engines. This paper aims at investigating the effects of a low pressure cooled EGR system on the performance of a 2-cylinder turbocharged SI engine. In a first stage, experiments are carried out at 3...

Knock occurrence and fuel enrichment, which is required at high engine speed and load to limit the turbine inlet temperature, are the major obstacles to further increase performance and efficiency of down-sized turbocharged spark ignited engines. A technique that has the potential to overcome these restrictions is based on the injection of a precis...

The technique of liquid Water Injection (WI) at the intake port of downsized boosted SI engines is a promising solution to improve the knock resistance at high loads. In this work, an existing 1D engine model has been extended to improve its ability to simulate the effects of the water injection on the flame propagation speed and knock onset. The n...

The potential benefits of water injection on performance and emissions were investigated on a downsized PFI twin-cylinder turbocharged spark ignition engine. Experiments were carried out at high load condition (~15.5 bar IMEP) within the engine speed range from 3500 to 4500rpm with a step of 500 rpm. For each test case the effect of the injected wa...

Particle Image Velocimetry (PIV) and Phase Doppler Anemometry (PDA) have been applied to investigate the droplets size and velocity distribution of a water spray, under the control of a piezo-element driven synthetic jet (SJ). Tests were carried out under atmospheric conditions within a chamber test rig equipped with optical accesses at two injecti...

The opportunity of directly managing the spray formation and its characteristics has gained much interest in the last few years, due to the various active flow control methods available nowadays. In this work particle image velocimetry (PIV) has been applied to investigate the effect of a piezo-driven synthetic jet (SJ) on the droplet velocity dist...

In this paper, a downsized twin-cylinder turbocharged spark-ignition engine is experimentally investigated at test-bench in order to verify the potential to estimate the peak pressure value and the related crank angle position, based on vibrational data acquired by an accelerometer sensor. Purpose of the activity is to provide the ECU of additional...

Ever tighter restrictions on pollutant emissions, energy security and a continuous drive for improving fuel economy have extended the range of application for direct injection in spark ignition engines and promoted the use of alternative fuels. Direct injection features higher soot formation compared to external mixture preparation, and therefore,...

The paper reports results of an experimental investigation to explore the potential of a synthetic jet (SJ) actuator to control a water spray. Particle Image Velocimetry (PIV) and Phase Doppler Anemometry (PDA) have been applied to characterize, in terms of velocity vector distribution and droplets size, the spray behavior generated by a misting no...

Given the instability in supply and finite nature of fossil fuels, alternative renewable energy sources are continuously investigated throughout the production–distribution-use chain. Within this context, the research presented in this work is focused on using butanol as gasoline replacement in a Direct Injection Spark Ignition engine. The impact o...

The paper reports the results of an experimental investigation carried out in a prototype optically accessible compression ignition engine fuelled with different blends of commercial diesel and n-butanol. Thermodynamic analysis and exhaust gas measurements were supported by optical investigations performed through a wide optical access to the combu...

This work reports the results of X-ray μ-tomographic investigation on the inner structure of high pressure fuel sprays. X-ray imaging is widely used in industry where non-destructive and high accuracy measurements of the samples morphology are required. A high flux beam can overcome the problems related to the low absorption of hydrocarbon chains a...

In this paper, the study on the effects of n-butanol on the combustion process in a DISI engine has been conducted.Experiments were performed on a direct injection SI engine operated on gasoline and butanol, with combined analysis of in-cylinder pressure traces, exhaust emissions and optical data. The optically accessible power unit was fitted with...

The effect of n-butanol on the combustion process in a DISI engine was investigated through in-cylinder pressure measurements and optical data. An optical engine was equipped with a commercial head and with high pressure wall guided injection system. 2000 rpm engine speed was chosen as representative for mid-road load automotive use. Two partially...

Crank angle resolved imaging in the UV-visible spectral range was used to investigate flame front characteristics during normal combustion, surface ignition and light knock conditions. 'Line of sight' measurements provided information on local wrinkling: the evaluation was based on a statistical approach, with multiple frames taken at the same cran...

The use of alcohols as alternative to gasoline for fuelling spark-ignition (SI) engines is widespread. Growing interest is paid for n-butanol because of its characteristics that are similar to gasoline. If compared with other alcohols, n-butanol has higher energy content and miscibility with gasoline, lower hygroscope and corrosive properties makin...

In this study, experiments were carried out in an optical single-cylinder Direct Injection Spark Ignition engine fuelled with n-butanol and gasoline, alternatively. The engine is equipped with the head of a commercial turbocharged engine with similar geometrical specifications (bore, stroke, compression ratio). The head has four valves and a centra...

Processes of the combustion of liquid fuels and solid are more complex than combustion of fuel gases. With reference to liquid fuels occur additionally processes of vaporization of the fuel, and with reference to solid fuels – decomposition of the solid phase with processes of melting and vaporization, pyrolysis, or gasification. This simultaneous...

This work reports results of an experimental investigation carried out on a multihole injector for direct injection spark ignition engines by using phase Doppler anemometry (PDA). Results of droplet size and velocity were compared testing n-butanol and gasoline injected at 5 and 10 MPa in a vessel at atmospheric pressure and ambient temperature. Ex...

Studies concerning the combustion analysis in spark ignition engines generally feature measurements of in-cylinder pressure traces and exhaust emissions. Combined thermodynamic and optical investigations can provide significant insight into specific phenomena and a more complete understanding of combustion processes. While the latter category of in...

Liquids with stable suspensions of nanoscale materials are defined as nanofluids. As reported in recent scientific literature, a very small amount of suspended nanostructures has the potential to enhance the thermo physical, transport and radiative properties of the base fluid. One of the main applications of this technology is in the field of comb...

Alcohols are largely used in spark-ignition (SI) engines as alternative fuels to gasoline. Particularly, the use of butanol meets growing interest due to its properties that are similar to gasoline, if compared with other alcohols. This paper aims to make a comparative analysis on the atomization process of gasoline and n-butanol fuel injected by a...

Ultraviolet (UV)-visible-near infrared (IR) multiwavelength extinction spectroscopy was applied in the exhaust line of an automotive common rail diesel engine to investigate the postinjection strategy impact on the fuel vapor. Four fuels were tested: a baseline diesel and three blends of diesel with 20% by volume of rapeseed methyl ester (RME), 20%...

Currently, direct injection (DI) for gasoline engines is a primary trend for improving efficiency allowing reduced fuel consumption and the possibility to meet stringent emission standards. A large temporal and spatial variation of mixture composition near the spark location during low speed and high load operation are driving the demands for signi...

The use of alternative fuels, as biodiesel and ethanol, for light duty CI engines to approach the target of ultra low NOx and PM emissions without fuel economy penalty has been widely investigated. Recently, it is growing the interest in the butanol as a viable alternative either single or blended with conventional based fuels both to cut the deman...

The target of a sustainable mobility has led to investigate advanced combustion modes and fuels technologies. On the other side, the increasing global energy demand and the decreasing fossil-energy resources are enhancing the interest in the use of renewable alternative fuels for compression ignition engines with the target of near-zero emission le...

Combustion process was studied from the injection until the late combustion phase in an high swirl optically accessible combustion bowl connected to a single cylinder two-stroke high pressure common rail compression ignition engine. Commercial diesel and blends of diesel and n-butanol (20%: BU20 and 40%: BU40) were used for the experiments. A pilot...

Split injection events are being considered also in gasoline direct injection (GDI) engines. Under some regimes, they are already employed to increase the temperature and maximize the efficiency of the catalytic converter or to reduce the engine tendency to knocking. Alternatively, under moderate or low loads and speeds, split injection may be adop...

Using the geometric compression ratio, calculated without considering crevices, usually ensures good accuracy when performing heat release analysis and other evaluations based on recorded in-cylinder pressure traces. This is due to the fact that top-land, head gasket, spark plug thread and other crevices amount to a small percentage of the clearanc...

Optical diagnostic was applied to undiluted engine exhaust to supply a low cost and real time evaluation of the oil dilution tendency of selected fuels. Specifically, UV-visible-near IR extinction spectroscopy was applied in the exhaust line of a Euro 5 turbocharged, water cooled, DI diesel engine, equipped with a common rail injection system. The...

The use of biodiesel as alternative to fossil fuel for light duty CI engines to reduce greenhouse gas emissions was widely investigated. However, poor stability of biodiesel-diesel mixture limits the use of biodiesel to low volume concentrations. This paper presents the results concerning the use of a novel fuel additive package containing antioxid...

In this paper the investigation with X-ray Tomography on the structure of a gasoline spray from a GDI injector for automotive applications based on polycapillary optics is reported. Table-top experiment using a microfocus Cu K X-ray source for radiography and tomography has been used in combination with a polycapillary halflens and a CCD detector....

The study of transient high pressure fuel sprays by X-ray based techniques is worldwide diffused. Synchrotron radiation is successfully exploited for this aim because of its high intensity and pulsed nature. However top-table application are unusual. This work reports the structure of a gasoline spray from an automotive GDI injection system obtaine...

This paper is focused on the study of the effects of the injection strategy and fuel blends on spray combustion and soot formation in compression ignition engines. UV-visible natural emission spectroscopy was applied in the combustion chamber of a single cylinder high swirl compression ignition engine equipped with a common rail multi-jet injection...

Recent studies have shown that biobutanol can play a significant role in a sustainable, non-petroleumbased, industrial system. About the use in spark-ignition engines, butanol blended with conventional hydrocarbon fuels can increase fuel octane rating and power for a given engine displacement and compression ratio. Several reference studies measure...

Detailed experimental information on the early stages of spark ignition process represent a substantial part for guiding the development of engines with higher efficiencies and reduced pollutant emissions. Flame kernel formation influences strongly combustion development inside the cylinder, especially for a direct injection spark ignition engine....

Multi-wavelength ultraviolet-visible extinction spectroscopy was applied to follow the evolution of fuel vapor injected by post-injection along the exhaust line of a common-rail turbocharged direct-injection diesel engine at moderate speed and load. The exhaust line was specifically designed and customized to allow the insertion of the optical acce...

One promising approach to reduce pollutants from compression ignition engines is the Partially-Premixed- Combustion in which engine out emissions can be reduced by promoting mixing of fuel and air prior to auto-ignition. A great interest for a premixed combustion regime is the investigation on fuels with different reactivity by blending diesel with...

Alcohol blends with hydrocarbon fuels for spark-ignition engine increase fuel octane rating and power for a given engine displacement and compression ratio. In this work, the influence of butanol addition to gasoline was investigated. The experiments were performed in a ported fuel injection single cylinder SI engine with an external boosting devic...

Fuel blend of alcohol and conventional hydrocarbon fuels for a spark-ignition engine can increase the fuel octane rating and the power for a given engine displacement and compression ratio. In this work, the influence of butanol addition to gasoline in a port fuel injection, spark-ignition engine was investigated. The experiments were realized in a...

The addition of alcohol to conventional hydrocarbon fuels for a spark-ignition engine can increase the fuel octane rating and the power for a given engine displacement and compression ratio. In this work, the influence of butanol addition to gasoline was investigated. The experiments were performed in an optical ported fuel injection single cylinde...

Optical imaging and UV-visible detection of in-cylinder combustion phenomena were made in a single cylinder optically accessed high swirl multi-jets compression ignition engine operating with two different fuels and two EGR levels. A commercial diesel fuel and a lighter fuel blend of diesel (80%) and gasoline (20%), named G20, were tested for two i...

In this work preliminary results on simulation of X-ray propagation in media characterized by low index of both refraction and absorption are reported. A 3D simulation software reproduces parallel X-ray beam colliding the samples while the emerging field distribution is evaluated at the detector place. The simulation code has been structured in ord...

To meet the future stringent emission standards, innovative diesel engine technology, exhaust gas after-treatment, and clean alternative fuels are required. Oxygenated fuels have showed a tendency to decrease internal combustion engine emissions. In the same time, advanced fuel injection modes can promote a further reduction of the pollutants at th...

The paper presents results of an experimental investigation of the fluid dynamic processes during the air/fuel mixture formation period between an evaporating diesel spray and swirl air flow under realistic engine conditions. Particle Image Velocimetry (PIV) experiments have been carried out using an optically accessible prototype 2-stroke Diesel e...

To meet the future stringent emission standards, innovative diesel engine technology, exhaust gas after-treatment, and clean alternative fuels are required. Oxygenated fuels showed tendency to decrease internal combustion engine emissions. In the same time, advanced fuel injection modes can promote further reduction in pollutants at the exhaust wit...

First use of a Cu X-ray source in combination with polycapillary halflens (or semilens) and a Photonic Science CCD detector for investigating highly dense jet injection sprays are reported. It is shown that in the energy range used the absorption signal is above the background level indicating but interaction of the beam with the fuel is weak. Thes...

In this work preliminary results on simulation of X-ray propagation in media characterized by low index of both refraction and absorption. First approach has proved the feasibility of typical Math code application for the analysis of X-ray imaging measurements performed by means of high-flux and low-divergent beams shaped by polycapillary half lens...

Laboratory X-ray techniques based on polycapillary optics have been first used for studying high dense sprays of the jet injection systems. Polycapillary optical elements are well known systems that enable shaping divergent X-ray beams (with energy of up to 30 keV) as well as to get high contrast image of the object studied due to the suppression o...

In diesel engines, fuel is injected into the engine cylinder close to the end of the compression stroke. During a phase known as ignition delay, the fuel spray atomizes into small droplets, vaporizes, and mixes with air. As the piston continues moving towards TDC, the mixture temperature reaches the fuel ignition point, causing instantaneous igniti...

In this study, the spray from a multi-hole GDI injector has been characterized applying the Imaging and the Phase Doppler Anemometry techniques. A multi-holes injector, with a hollow-ellipsoid footprint structure, has been used. The spray pattern evolution has been analyzed injecting commercial gasoline at different injection pressures (10, 15 and...