bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fuels systems and components for future airliners fuelled with liquid hydrogen
Authors: Tamburrano P , Romagnuolo L , Frosina E , Caramia G , Distaso E , Sciatti F , Senatore A , De Palma P , Amirante R 
Published: December 2022

Abstract
The prospect of using liquid hydrogen as fuel in airliners in place of kerosene-based fuels is regarded as one of the most effective solutions to achieve low-carbon air transport in the near future, which is a target defined by the EU to reduce global warming caused by CO2 emissions. The development of hydrogen-fuelled airliners must face issues related to the production and supply chain of green hydrogen, to the fuel systems for hydrogen handling aboard aircraft, and to the combustion of hydrogen. This paper is concerned with the literature study of fuel systems for hydrogen, keeping in mind that the other two aspects are currently being studied extensively in industries and universities. This paper analyses difficulties, proposals and advances related to the four main parts composing future fuel systems for hydrogen-fuelled airliners: fuel storage, fuel delivery, thermal management and fuel metering.
Development of a novel CO2 splitting fixed-bed reactor based on copper-doped cerium oxide
Authors: Milanese Marco , Manzo Andrea , Colangelo Gianpiero , Risi Arturo de 
Published: December 2022

Abstract
Global warming has received widespread attention in recent years due to the accumulation of carbon dioxide. Looking at the current energy landscape, new technologies must be developed to reduce CO2 emissions. The present work is aimed to develop and test a new prototype of an innovative reactor for the conversion of CO2 into CO, operating according to a two-phase thermochemical cycle. The innovative and main aspect of this study was the use of a reactor coupled with a new type of catalyst, a copper-doped cerium oxide (Cuδ+2Ce(1-δ)O2), which allowed to decrease the temperature of the reaction up to 850°C, much lower than the models present in the literature, tested on 1300/1400°C and even beyond.
Hydrogen production from low-quality water: challenges and perspectives
Authors: Baldinelli Arianna , Cinti Giovanni , Barelli Linda , Bidini Gianni 
Published: December 2022

Abstract
The Next Generation EU plan fosters the development of a large capacity for hydrogen generation. However, water and energy resources are strictly connected to an indissoluble nexus. For that, water electrolysis may counteract the coexistence of two primary UNO Sustainable Development Goals humankind must face to achieve a prosperous and equal society, namely SDG 7 (Affordable access to renewable energy sources) and SDG 6 (clean water). To design innovative energy systems implementing hydrogen as an efficient and sustainable vector, water resources need careful management and energy use ought not to compete with freshwater delivery. Therefore, the present study reviews the technologies available for hydrogen production and their fitness to water quality standards. Among the feeding possibilities to be scrutinized, wastewaters and saline waters are worth attention. Each source of water asks for a specific design and management of the water treatment pre-process. Since these steps are energy-demanding, in some applications, the direct use of low-quality water to produce hydrogen may be envisaged. An example is the direct feeding of seawater to Solid Oxide Electrolysers (SOE). SOEs appear more promising than commercial low-temperature electrolysis systems since water steam production integrates the function of preliminary water treatment.
Analysis and performance assessment of the use of ammonia-based nano additive for lean combustion
Authors: Di Gloria P , Strafella L , De Giorgi M G , Ciccarella G , Castelluzzo G G , Baldassarre F , Ficarella A 
Published: December 2022

Abstract
In recent years, considerable progress has been made in exploring new applications of fuel additives to reduce emissions. Reduction of total nitrogen oxide (NOx) emissions can be achieved by decreasing the flame temperature by using fuel emulsified with water and/or using ammonia-based nano additives such as urea. The use of water as part of the hydrocarbon fuel is also one of the prospective directions in the development of new types of fuel systems. For the preparation of emulsified fuel, it is desirable to achieve greater stability of the emulsified fuel with minimum expenditure of chemicals and energy, so that the emulsified fuel can be used for a longer period. The paper analyzed the influence of nano-dispersed urea particles, water, and surfactant (Span 80/Tween 80) on the combustion stability and emission characteristics of aviation fuel. The experimental campaign was conducted on a test stand (a 300kW liquid vortex combustor of 300 kW) consisting of a cylindrical combustion chamber with four optical windows and equipped with high-precision pressure sensors, thermocouples, and an exhaust gas analyzer for acquiring emissions. The experimental campaign was conducted at a constant fuel/air ratio (Φ). One of the main focus is related to the stability of the emulsion. Chemiluminescence imaging was performed to characterize the effects of the additive on flame emissions. In addition, a statistical and spectral analysis was performed using the pressure sensor for instability analysis. Exhaust gas analysis was performed both with the additive described above and without additive for a constant Φ condition. The analysis was performed for NOx, carbon monoxide (CO) and carbon dioxide (CO2) and oxygen (O2).
Experimental and numerical analysis of the convective flow induced over a dry-ice bank with Particle Image Velocimetry
Authors: Vitali M , Biancini G , Marchetti B , Corvaro F 
Published: December 2022

Abstract
The utilization of carbon dioxide in new technologies opens a wide range of interesting applications which depend strictly upon heat transfer phenomena. The momentum on the deployment of Carbon Capture Utilization and Storage (CCUS) infrastructures will potentially enlarge the diffusion of technologies for the utilization and recycling of CO2. Such applications, however, require appropriate laboratory investigations for a complete characterization of the CO2 thermo-fluid-dynamic behaviour. The safety management of carbon dioxide is important; thus, accurate modelling is needed since solidification and sublimation of dry-ice can be very challenging to predict analytically. One of the dry-ice applications is the utilisation in refrigeration cycles and in novel CO2 heat pump technologies. For this reason, knowledge about the entity of sublimating CO2 from a solid surface is crucial. This work proposes an innovative experimental setup for the measurement of temperature and convective velocity fields in the sublimating phenomenon of CO2 under atmospheric conditions by means of Particle Image Velocimetry (PIV). The experimental results have been compared and validated with numeric CFD models.
Thermal control of lithium-ion batteries for electric cars by metal foam partially filled with Phase Change Material
Authors: Buonomo B , Manca O , Menale F , Nardini S 
Published: December 2022

Abstract
A viable solution to environmental problems related to pollutant emissions from internal combustion engine vehicles is electric cars. The main problem with electric vehicles, which also limits their widespread use, is due to lithium batteries and in particular their thermal control. Thermal control of lithium batteries is an extremely topical issue since it is not only related to the performance of the vehicles on which they are mounted, but also to the safety of the vehicles and drivers. For this purpose, both factors internal to the battery itself and external causes such as environmental conditions must be considered.
In this work, a thermal control system based on metal foams partially filled by the phase change material (PCM) was numerically investigated as a possible application for cooling lithium batteries. For this purpose, a two-dimensional numerical model was constructed in which the PCM partially fills the metal foam. The finite volume method used through the ANSYS Fluent code was used for the governing equations, which are written assuming local thermal equilibrium. Several cases were simulated for different values of the external convective heat transfer coefficient. The results obtained, are reported in terms of temperatures and liquid fractions. Comparisons with partially filled and totally filled cases by PCM in the thermal control system are reported to show the advantage obtained, in terms of thermal control, with a composite system of metal foam and PCM.
Hybrid Propulsion for Motorcycle Application to Reduce Engine-out Emissions: An Analytical-Experimental Investigation
Authors: Iodice P , Fornaro E , Cardone M 
Published: December 2022

Abstract
All over the world, motorcycles represent an important share of motorized vehicles helping to meet daily urban transport needs, thus, particularly in urban contexts, two-wheelers impact to air pollution is significant. In a previous experimental investigation, emissions of regulated pollutants were measured in the exhaust of a four-stroke motorcycle belonging to the Euro-3 legislative category. Since exhaust emissions and fuel consumption are very sensitive to variations in vehicles instantaneous speed and acceleration, such experimental results are used in this research to recognize the kinematic parameters that cause higher CO and HC emissions. The hybrid electric propulsion is then proposed to reduce exhaust emissions in particular driving conditions which include high levels of acceleration with resultant sudden steep increase in engine speed. In such phases, in fact, an enrichment of the air/fuel mixture is needed which affects the catalyst conversion efficiency. Subsequently, the power requirements and the grade of electrical assistance in such driving situations are estimated by a procedure based on both the measured exhaust emissions and the kinematic parameters that characterize the driving dynamics collected during the experimental tests. Finally, the share of CO and HC emissions that could be saved utilizing a hybrid motorcycle instead of a conventional thermal motorcycle is calculated through an environmental analysis.
Towards the development of smart weather routing systems for leisure planing boats
Authors: Ciampolini M , Balduzzi F , Romani L , Bellucci L , Bianchini A , Ferrara G 
Published: December 2022

Abstract
Weather routing (WR) systems are widely adopted in the maritime transport since safety of goods and saving of fuel are crucial for shipping companies. However, the need of protecting the local coasts and reducing CO2 emission is making WR attractive even for the market of leisure boats, especially if comfort and safety are also accounted. In the present study, a prototype of a WR system is presented. The developed tool implements the Dijkstra’s algorithm to find the fuel-optimal path while ensuring comfort and safety. A computationally efficient digital twin of a planing boat, based on a 2D+t model and a powertrain mapped model, has been implemented for the estimation of the fuel consumption and the evaluation of vertical accelerations. The methodology for the acquisition of online weather data is presented, together with the strategy for the assessment of comfort and habitability. The application of the WR tool in a typical path of the Tuscan Archipelago shows improvements in fuel usage and comfort even in moderate weather conditions. The influence of each weather variable on fuel efficiency is assessed, highlighting the requirement of an accurate dynamic modelling. Criteria for the graph design are also outlined, showing a wrong estimation of comfort and fuel usage in case of low-definition graphs. The paper proves the potential and the effectiveness of the developed tool, moving toward a greener and more comfortable navigation in local seas.
CFD simulation of water droplet adhesion on the GDL of a low temperature PEM FC in air cross-flow conditions
Authors: Antetomaso C , Irimescu A , Merola S S , Vaglieco B M , Di Micco S , Jannelli E , Scarpati G , Simeoni E 
Published: December 2022

Abstract
Water management is a critical challenge in low temperature (LT) Proton Exchange Membrane Fuel Cells (PEM FC); condensed liquid appears mainly at the cathode side, where water from the reduction reaction is generated. Differences in concentration may result in the transfer of water to the anode side across the membrane electrode assembly (MEA). Excessive liquid can negatively affect fuel cell performance, causing low efficiency and instability. This occurs due to water movement through porous layers and channels that are the essential pathways for the reactant gas to reach the MEA. However, water is necessary in the PEM FC for enhancing ion conductivity of the membrane. The present study can contribute to the optimization of LT PEM FCs by analysing the water behaviour under flow conditions. The widely used Volume Of Fluid (VOF) method is adopted for simulating multiphase flow. CFD simulation of droplet adhesion on the gas diffusion layer (GDL) is performed to describe the interaction between water and gas flow. Deformation and oscillations of droplets with diameters in the 0.3-1.0 mm range are investigated by considering airflow rates up to 15.0 m/s. CFD analysis is validated by optical data from digital imaging with high spatial (up to 5.8 μm/pixel) and temporal (up to 1.0 ms) resolution.
Comparison on the energy absorbed of volumetric and centrifugal pumps for automotive engine cooling
Authors: Di Giovine G. , Mariani L. , Di Bartolomeo M. , Di Battista D. , Cipollone R. , Carminati A. 
Published: December 2022

Abstract
Engine thermal management can reduce significantly CO2 emissions in road vehicles without altering sensibly the engine layout. However, more efficient auxiliaries also participate to fuel consumption saving and, therefore, to CO2 emissions reduction. Typically, centrifugal cooling pumps are adopted as circulating devices, but their efficiency varies highly with rotational speed, wasting energy during real operation despite being optimized at the design point. Instead, volumetric pumps keep a high efficiency also far from it, enhancing the overall engine efficiency. In this paper, the performances of a screw-type volumetric pump have been compared with those of a centrifugal pump considering the same cooling circuit of a mid-size engine for passenger vehicles. Both pumps have been designed to satisfy the cooling flow rate required by the engine during a homologation cycle, while verifying their capability to cool the engine operating at maximum power. Once prototyped, the pumps performance maps have been measured, showing a high Best Efficiency Point for both cases. However, the screw pump has better performance in off-design conditions, being the centrifugal pump efficiency strictly dependent on its rotational speed which significantly changes during a real driving. The comparison of the two pumps has been done by reproducing the WLTC on a dynamic test bench. The rotational speed of the volumetric pump has been adjusted to deliver the same flow rate produced by the centrifugal pump as requested by the engine. Results show that the prototyped screw-type volumetric pump absorbs 21% less energy than the prototyped centrifugal pump, reducing CO2 emissions by 0.28 g/km.
Model Parameterized Assessment of a Thermal Storage Unit for Engine Oil Warm-up Improvement
Authors: Vittorini Diego , Diomede Domenico Di , Battista Davide Di , Carapellucci Roberto , Cipollone Roberto 
Published: December 2022

Abstract
Despite the attention paid to components downsizing and down weighting, as well as to combustion control and exhaust gases after-treatment, friction reduction remains a promising area of intervention when it comes to the reduction of the environmental impact of internal combustion engines. The larger gain must be sought at cold starts, when the viscosity of the lubricant oil is higher and does not allow proper friction reduction. Moreover, during the first phases of engine operation, the metallic masses are not yet warm and do not contribute to the thermal stabilization of the lubricant. Further consequences of unfavourable thermal conditions are increased specific fuel consumption and pollutant emissions. Proper thermal management could effectively speed up the reaching of the design operating temperature of the oil and positively affect both homologation and on-road operation. The abundance of waste thermal energy during normal operation supports the option of on-board thermal storage for faster oil heating: water, heated by exhaust gases or residual thermal energy from previous use or by a combination of the two, can be stored inside a thermally insulated tank and serve as heating fluid in a dedicated water/oil heat exchanger. The paper presents a model based evaluation of this opportunity. The model has been validated thanks to an experimental activity carried out on an IVECO 3.0 L light-duty diesel engine, during a transient cycle (i.e., homologation one) reproduced on a dynamometric test bench. Different configurations in terms of hot storage volume, hot storage initial temperature, and the flow rate of the hot water during operation have been studied, producing optimized values for the hot water and storage unit design.
Feed-Forward Neural Network for health monitoring of a parallel hybrid electric power system
Authors: De Giorgi M G , Donateo T , Ficarella A , Menga N , Spada Chiodo L , Strafella L 
Published: December 2022

Abstract
Hybrid engines are becoming more and more widespread. Electric energy instead is a valid help to reduce the environmental impact. In hybrid engines, the number of components is higher and this results in a decrease in reliability. With Engine Health Monitoring (EHM) we mean the set of techniques used to monitor the health status of a system based on the values assumed by some related parameters. Artificial Intelligence (AI) methods are widely used nowadays in this discipline. In this paper, an EHM approach was developed to monitor the health status of some components constituting an hybrid turboshaft. The dynamic model of the hybrid electric power system is described in an accompanying paper. Feed-Forward Neural Network (FFNN) is used as AI tool to built the just cited system. The engine modelled with Simulink, was used to perform a series of steady-state simulations implementing a degradation condition in some selected components. The degradation condition was simulated by changing the value of the Performance Parameters (PPs) related to each of the selected components. The results of the simulation were used to obtain a dataset useful to train the FFNN to predict the values of the same PPs in a degraded case.
Synergy between Cities and surrounding territory to achieve the international agreements on energy and CO2 reduction. The Municipality of Avezzano in the Abruzzo Region (Italy) case.
Authors: Abbate Simona , Paolo Luca Di , Battista Davide Di , Carapellucci Roberto , Cipollone Roberto 
Published: December 2022

Abstract
Cities have a fundamental role in the reduction of greenhouse gas emissions. The European Community has already addressed a specific planning under the actions referred as SEAPs (Sustainable Environmental Action Plans) and SECAPs (Sustainable Energy and Climate Action Plans). In fact, Municipalities are the smallest entities with a political responsibility in terms of Energy and Environmental Planning, and they must participate, as commitment, to the European Directives on Energy and fight to Climate change. They, finally, are often the most unsustainable environments due to the aggregation of many activities, energy and CO2 related.
In this paper, for a typical small/medium-size Italian city (Avezzano), an evolution of the SEAP and the SECAP has been supposed and elaborated within the Covenant of Mayors. The synergy between the energy consumption of a city and the capability of a territory to mitigate CO2 and to finalize renewable energy to electricity production appears to be the right answer to the even more stringent commitments imposed by the gas crisis at worldwide level which is pushing to a new switch-on of coal fired power plants.
Starting from the data and the list of actions elaborated to fulfil the SECAP, two scenarios have been evaluated to create a zero CO2 emission city. A model with multiple inputs has been elaborated with the main aim of reducing GHG emissions or compensating them, trying to sustain the effort to keep limited to 1,5 °C the maximum Planet’s temperature increase. Increasing the renewable energy production for all the energy final needs, exploitation of unused area finalized to carbon sequestration, energy efficiency and specific actions on the transportation sectors give all together a formidable contribution to reach this goal and to give to energy and environmental planning the right role it deserves.
Bypass Control strategy of a Pump as Turbine in a Water Distribution Network for energy recovery
Authors: Filannino Domenico , Stefanizzi Michele , Capurso Tommaso , Balacco Gabriella , Camporeale Sergio M. , Torresi Marco 
Published: December 2022

Abstract
Water Distribution Networks (WDNs) are subject to leakages due to pipes aging, resulting in water and pressure losses. These issues are solved by installing Pressure Reduction Valves (PRVs) to decrease the pressure in WDNs. Depending on the application, PRVs can waste large amount of energy, hence the substitution of PRVs with Pumps used as Turbines (PaTs) can be a good compromise in terms of economic and technical aspects to reduce leakages and recover energy. Currently the share of PaT is not yet fully developed due to the certain technical challenges yet to be addressed, as providing an affordable control strategy closer to the real working conditions in a WDN. Hence, more experimental activities are required. For these reasons, in this work an experimental campaign was carried with the aim to investigate the behavior of a PaT according to a possible layout that could be embedded into a WDN. Firstly, the machine was characterized both in pump and turbine modes. Moreover, the machine working conditions limits have been analysed in terms of runaway and blocked-rotor curves. Then, turbine tests were carried out at constant speed with a typical hydraulic control scheme by means of a PRV installed in series to the PaT and a second one installed on a bypass. As a result, this analysis highlighted the feasibility to recover a consistent amount of hydraulic energy otherwise wasted under typical WDN daily pressure and flow rate patterns, with promising results in terms of the operating point control of the machine.