bluuebunny/crossref_metadata_2025 huggingface dataset:
NextGen Infrastructures: Enhancing Cyber-Physical Resilience/Sustainability by Virtual Energy Storage
Authors: Ardebili Ali Aghazadeh , Padoano Elio , Longo Antonella , Ficarella Antonio
Published: December 2024

This systematic review investigates the pivotal role of virtual energy storage (VES) in enhancing the resilience of energy systems. By systematically selecting and analyzing 158 articles, we address four key research questions about specific features of VES that enhance energy system resilience, how these features influence the overall resilience of energy systems, the enabler technologies associated with VES that impact the resilience of cyber-physical systems, and lastly, we discuss the challenges, and future research directions pertaining to the utilization of VES for bolstering resilience. Highlighting the importance of VES, the findings provide insights for policymakers, energy practitioners, and researchers aiming to enhance the resilience of energy systems in the face of increasing uncertainties and disruptions. Furthermore, this study provides valuable insights for the resilience engineering and energy engineering communities by identifying main features of energy resilience and key enabler technologies of VES for enhancing energy storage and system resilience.
Towards the target of the Renewable Energy Directive (RED) III using photovoltaic and batteries: The case study of Italy
Authors: Onori Filippo , Milletti Tommaso , Rossi Mosè , Comodi Gabriele
Published: December 2024

The European Green Deal has set the ambitious goal of achieving climate neutrality by 2050, which requires an important energy transition. The Renewable Energy Directive (RED) III has raised the ratio between renewable energy production and energy consumption from 32 to 42.5%; however, renewables are intermittent and energy storage systems are needed to overcome this issue. This paper analyses the current energy situation in Italy by deepening the study in its different market zones and finding out the optimal capacity of both the photovoltaic and batteries per each zone which allows to achieve the target set by the RED III. At the same time, the energy import from abroad countries is reduced as well. An optimal management strategy of Battery Energy Storage Systems (BESSs) has been proposed by using an in-house developed Python code. Results showed that the Southern market zones (e.g., Calabria, Sicily, and South) have already reached the RED III target, while the Central and Northern ones still need to install a new photovoltaic capacity of 32.5 GW. After redistributing the excess of energy from the South to the North, the increase in the energy production from the additional photovoltaic capacity coupled with batteries would lead to a reduction of the energy import from abroad by 47.78% compared to 2022. Finally, the economic investment required to achieve this objective would be equal to 38, 159, 375 k€ with a Payback Period (PBP) of 10.4 years considering an interest rate of 4.74%.
Transient investigation of a residential building air conditioning system with heat pump and PV/T modules
Authors: Buonomo Bernardo , Manca Oronzio , Nardini Sergio , Palmieri Giulio , Plomitallo Renato Elpidio
Published: December 2024

Nowadays, in response to the European energy crisis and the imperative to reduce carbon emissions, the study of energy systems plays a crucial role. New energy systems and configurations have been studied in the recent years to improve the energy efficiency and reduce greenhouse gases emissions. This study investigates the dynamic performance of a residential HVAC system integrating photovoltaic thermal (PV/T) modules and a heat pump. The system aims to harness thermal energy from solar radiation using PV/T modules to generate electricity and heat water. The case study is performed considering a building located in Caserta. According to the authors knowledge, there is a lack of information regarding the modeling of PV/T systems with a heat pump. Inside the studied system, the thermal energy is stored in a storage tank for later use. An auxiliary heater is activated to produce domestic hot water (DHW) when the PV/T cannot provide it. The system components are modeled using TRNSYS. A dynamic simulation approach is adopted to assess the system performance under varying environmental conditions and building load demands. These load demands are used to model real-world scenarios. This kind of system offers several advantages. Firstly, the PV/T modules serve a dual purpose of electricity generation and water heating, maximizing energy utilization. Secondly, the heat pump enhances the overall efficiency of the system by extracting heat from the water stored in the puffer tank, thereby reducing reliance on conventional heating methods. The findings of this study provide valuable insights into the performance and feasibility of integrating PV/T in residential HVAC systems. During the winter season, the solar fraction, the ratio between energy supply from PV/T and total energy demand, averages about 25%. When heating is not required, the PV/T panels manage to ensure the production of approximately 75% of DHW.
Preliminary analysis of an integrated ICE-gasifier plant for power generation from plastic waste material
Authors: Grilli N , Ciampolini M , Bosi L , Romani L , Ferrara G
Published: December 2024

The escalating global production of plastic waste is a challenge that must be rapidly addressed, but it also conceals opportunities. Currently, only a minor portion of the worldwide plastic waste is recycled, with the remainder destined for either incineration or landfill. In this context, gasification emerges as a sustainable alternative to conventional waste management methods, offering a substantial reduction in pollutant emissions. Dioxins and furans emissions, in fact, are drastically reduced when compared to incineration. Additionally, in contrast to landfill disposal, gasification allows for the recovery of chemical energy contained in plastic that would otherwise be wasted. The study of plastic gasification is gaining attention and several studies demonstrated feasibility and effectiveness, despite it is not as established as biomass gasification. The present paper aims at taking a step forward by conceptualizing an integrated gasifier-internal combustion engine power plant, operating in a closed-loop system. This layout offers potential benefits from both energetic and environmental points of view, respectively related to the recovery of engine waste gas and CO2 emission reduction. The proposed plant is based on the steam/CO2 gasification technique, which allows the complete conversion of input CO2 into syngas under certain thermochemical conditions. This feature enables the operation of engine and gasifier in a closed-loop system, directly exploiting the exhaust gas to perform plastic gasification. A thermodynamic feasibility study is performed, accounting for the efficiency of the main components, the heat fluxes and the heat absorbed by the endothermic reactions inside the gasifier. The setup of the proposed power plant shows an energy conversion efficiency up to 18% in a pure electric generation scenario and up to 56% in a cogeneration scenario.
Energy balance in innovative biopolymers production for sustainable 3D printing using lignocellulosic feedstocks
Authors: Cavalaglio Gianluca , Gelosia Mattia
Published: December 2024

This study, developed within the PRIN (Nation Relevant Research Projects) project BIOforTE, investigated the production of a bio-composite for 3D-printing systems. The raw material employed in the experimental campaign was Cynara Cardunculus (var. sylvestris) which was processed by organosolv method for the extraction of high-purity cellulose and technical lignin. The high-purity cellulose was used for the production of PLA and CNCs. The bio-composite for 3D-printing consisted of the uniform dispersion of technical lignin and CNCs in the thermoplastic biopolymer PLA. The preliminary results of the mass and energy flows were investigated, collecting the input data from the experimental campaigns, such as mass flows (reagents, solvents, water, etc.), energy flows (process temperature, electricity consumption, heating, cooling, etc.) and output flows (process yield, products, by-products, waste streams, residual energy, etc.). The collected data of the pathway aims at optimizing the energy and environmental performances of each phase. All stages of the process chain, from the biomass treatments and fractionation to the biopolymeric material production and its use for 3D printing will be analysed to create a database for the development of the inventory and the evaluation of the LCA. First pathway results are presented in form of energy consumption, chemicals, and water use, intermediate bioproducts and final bio-composite mass efficiency.
The importance of an accurate numerical model for the simulations of new generation district heating systems
Authors: Dénarié Alice , Aprile Marcello , Motta Mario
Published: December 2024

The aim of this work is to present a fast and accurate district heating simulation tool conceived to support the implementation of successful integrations of renewable energy sources along district heating networks. New generation district heating systems are facing new challenges related to increasing integrations of distributed renewable energy sources and new type of customers, such as prosumers. These connections introduce a great variety of low temperature highly variables energy profiles in the network that traditional modelling tools cannot properly simulate. Therefore, a specific thermo-hydraulic simulation model has been built to simulate the complex dynamics of entire network and its components, combining accuracy and rapidity. The model uses different numerical approaches to properly taking into account the thermal inertia of the components capacity, namely the water network and the users. The rapidity and reduction of computational effort is reached by the use of a Lagrangian approach based on the method of characteristics applied to the piping elements. Compared with the commonly used finite-volume and the node method, the proposed model shows accurate results at a lower computational expense and reducing numerical diffusion and artificial smoothing. In order to properly simulate the effects of the user behaviour on energy demand, flow rates and return temperatures of the network, a simplified but accurate user substation model is built with a lumped capacity approach. The model accuracy is investigated under real operating conditions with one-year hourly monitoring data of an Italian district heating network.
Energetic comparison between different configurations of a concentric magnetic gearbox for industrial applications
Authors: Amoresano Amedeo , Roscioli Silvia , Langella Giuseppe , Iodice Paolo
Published: December 2024

Mechanical gearboxes can achieve high torque densities. They often require recurring lubrication, cooling and maintenance, and reliability can be a significant issue, particularly for remote systems such as wind turbines, or during the operation of a ship under special conditions or circumstances that require an immediate response. For these reasons, a new type of gearbox is increasingly gaining ground, namely magnetic gearboxes (MG). It operates without contact between the moving parts and consists mainly of three concentric ‘rings’ with a number of permanent magnets and iron poles to achieve a specific gear ratio. This article presents an energy comparison in terms of induced torque between different configurations of a concentric magnetic gearbox in terms of material construction for the cores, magnets position and number of pole pairs. The data were realised using the two-dimensional Finite Element Method (FEM). The results show that although the polymer-based configuration shows some potential, the ferrous core with external magnets significantly outperforms it in terms of torque and efficiency.
Preliminary characterization of nano-silica gels for industrial applications in chilled showcases
Authors: Merli Francesca , Fraioli Francesco , Mastoori Mehrangiz , Buratti Cinzia
Published: December 2024

The aim of the paper is to characterize nano-silica gels for industrial applications in chilled showcases, achieving increased thermal insulation performance compared to current solutions, while maintaining high light transmission properties to improve transparency and colour rendering. Thin silica aerogel (3-mm thick) is a nanomaterial produced from polymers with tiny nanometric-sized pores, making it one of the lightest solids in the world. Its nanometric structure makes it ideal for thermal insulation, as it traps air in the nanopores, effectively cancelling convective heat transfer. Additionally, it is useful for gas adsorption, humidity control, and the protection of consumer goods, including food. The paper reports the assembly of several glazing prototypes and provides preliminary thermal and optical characterizations. A thermal transmittance reduction of about 33% was achieved by inserting the aerogel into the gap (thermal transmittance equal to 1.96 W/m2K vs. 2.91 W/m2K calculated for the same glazing system with only air). However, a slight deterioration in visible transmittance was measured, with the transmission peak decreasing from 0.83 to 0.80 when including aerogel.
Enhancing energy efficiency of buildings located in the Mediterranean area using Phase Change Materials (PCMs) integrated into mortar formulations.
Authors: Sarcinella Antonella , Cunha Sandra , Aguiar José , Frigione Mariaenrica
Published: December 2024

Phase Change Materials (PCMs) in building materials can significantly reduce energy consumption in heating and cooling systems. PCMs absorb, store, and release thermal energy by transitioning between solid and liquid states based on external temperatures, helping to regulate indoor temperatures and lower energy use. This study evaluates the thermal performance of various mortar compositions containing PCMs made from hydraulic lime and cement. The PCMs were developed using the “form-stable” method, incorporating a porous matrix of Lecce Stone (LS), known for its high porosity, and sourced from processing waste, supporting sustainability principles. The selected PCMs were Polyethylene Glycol (PEG) with molecular weights of 800 and 1000 g/mol, suitable for Mediterranean climate temperatures. The temperatures that characterize this geographic area were simulated in a climatic chamber to assess the thermal behavior of the mortars containing the PCMs across all four seasons. The results showed that mortars with composite form-stable PCMs effectively mitigated indoor temperature fluctuations, reducing the need for heating and cooling. Additionally, energy savings calculations demonstrated significant reductions in heating and cooling costs, underscoring the potential of the PCMs to enhance building energy efficiency.
Optimization of reversible heat pumps utilizing waste heat from electric power plants
Authors: Vasylyev Andriy , Sorce Alessandro
Published: December 2024

Current global climate targets aim to decarbonize all energy sectors. In the power generation sector, the increasing presence of Renewable Energy Sources (RES) has changed the role of Combined Cycle Gas Turbine (CCGT) power plants. They are becoming systems that need to provide more flexibility to the grid through ancillary and balancing services or reserve capacity.

At the same time, urgent action is needed to significantly reduce the carbon intensity of the heating sector, a major contributor to greenhouse gas emissions. Using the low-exergy waste heat from water-cooled CCGT condensers as a thermal source for vapor compression heat pumps serves two purposes. Firstly, it improves the economic viability of CCGT plants, which is crucial for ensuring the security of the electricity supply. Secondly, the heat produced provides a low-carbon alternative to conventional gas-fired boilers or less efficient air-source heat pumps.

This study evaluates the potential for recovering thermal energy from seawater cooling at the condenser of the 794 MWel CCGT plant in Vado Ligure operated by Tirreno Power. A high-temperature heat pump using R600 as the working fluid is proposed. Seawater is an advantageous heat source, and integration into the power plant site allows the heat pump to be operated at a lower cost than the retail price of electricity.

To assess economic and environmental performance, the case study focuses on the new Vado Ligure sports hall. This involves sizing the heat pump and analysing its impact, managing both heating and cooling demand using the same reverse cycle heat pumps.
Performance Analysis of a Power-to-Gas Storage System based on r-SOC
Authors: Ancona M A , Brunaccini G , De Pascale A , Ferrari F , Ferraro M , Italiano C , Santangelo T , Vita A
Published: December 2024

Power-To-Power (P2P) systems represent a promising technology to store the overgeneration from renewables generating a synthetic gas (mostly hydrogen or methane) and to convert the chemical carrier back into electricity during periods of energy demand peaks. In this context, the aim of this work is to propose, model and analyse an innovative P2P system that includes, as key components, a reversible Solid Oxide Cell (r-SOC) device and a reversible chemical reactor (RCR) working both as methanator and reformer. In the synthetic fuel production phase, water and electricity are converted into hydrogen by the r-SOC, which operates as an electrolyzer. Then, the hydrogen is in turn converted into synthetic methane by the RCR, operating as a methanator. During the discharge phase, instead, the RCR device operates as a reformer, fed by methane and water, and the r-SOC operates as a fuel cell, feeding the electricity production into the grid. The whole reversible P2P is modelled in Aspen HYSYS environment allowing to simulate both the design and off-design operation of the system. In addition, to increase the whole system’s performance, a heat recovery section is included in the model and optimized. Finally, a preliminary analysis to reproduce the behaviour of the system on varying the input available electric power will be analyzed and discussed, introducing and evaluating the key performance parameters for the system.
Thermally integrated innovative Carnot batteries to upgrade and dispatch low temperature sensible waste heat
Authors: Morosini Ettore , Alfani Dario , Renzoni Mario , Manzolini Giampaolo
Published: December 2024

This work focuses on innovative thermally integrated Carnot batteries exploiting low temperature sensible waste heat, available at temperatures between 70°C and 100°C, while adopting a sensible solid-based thermal energy storage system. The charging cycle is based on transcritical heat pumps operating with CO2-based mixtures, representing the most innovative aspect of the work, whereas the discharging cycle runs with conventional pure fluid ORC. The heat pumps adopting CO2 doped with a low fraction of hydrocarbons can achieve very high second law efficiencies (around 70%), even in a simplified cycle layout with a sensible heat source, storing heat in the low-cost storage operating between 50°C and 150°C. Similarly, an ORC with cyclopropane as working fluid is identified as the most promising solution for the discharging phase of the Carnot battery. Results show RTE of around 62% and 84% for the thermally integrated systems with waste heat sources at 70°C and 100°C, respectively, and an air-cooled ORC. Finally, calculations show that RTE close to 100% is possible with a water-cooled ORC. Both the computed values of RTEs and the high compactness and effectiveness of the innovative heat pumps highlight the necessity for additional research into thermally integrated Carnot batteries as a way to exploit and dispatch sensible waste heat.
Investigation of Cavitation Phenomena in a “High-Power” Piezohydraulic Pump: A Computational Fluid Dynamics (CFD) Approach
Authors: Sciatti Francesco , Domenico Vincenzo Di , Tamburrano Paolo , Sell Nathan , Plummer Andrew R. , Distaso Elia , Caramia Giovanni , Amirante Riccardo
Published: December 2024

Piezoelectric pumps, known as piezopumps, are highly versatile devices with applications in various fields due to their precise flow control, compact design, lack of magnetic interference, and low noise. These pumps are classified based on the number of pumping chambers, valve configuration, and driving power source mechanism. In fields requiring consistent flow rates and back pressures, particularly in fluid power applications, piezopumps employing a piezostack actuator as their power driving source are actively researched. This kind of piezopumps, also known as piezohydraulic pumps, operate using a piezostack actuator to drive a piston for fluid delivery, along with reed valves controlling fluid flow at the inlet and outlet of the pump chamber. The high operating frequency range of the piezostack actuator and reed valves, exceeding 1 kHz, allows piezohydraulic pumps to achieve significant flow rates despite the stack’s limited displacement. This enhances their performance without the need for increased size or power input. However, this also increases the risk of cavitation, which could lead to damage, reduced efficiency, and higher noise levels. Therefore, the purpose of this paper is to expand on previous research by using the CFD software Ansys Fluent to further investigate cavitation phenomena in a piezohydraulic pump developed at the University of Bath. In particular, the study focuses on simulating various oil flow scenarios through the pump with a fixed inlet pressure of 20 bar, while varying the opening of the inlet reed valve from the minimum (0.1 mm) to maximum (0.7 mm) value, as well as adjusting the pump chamber pressure.
Three-dimensional modeling of Alkaline Water Electrolyzers
Authors: Croci Federico , d’Adamo Alessandro , Pavan Nicolò , Cordisco Ilario
Published: December 2024

The main purpose of this paper is the development of a CFD modelling methodology for the simulation of alkaline water electrolysis. The growing concern about climate change is pushing more and more countries to facilitate ecological transition programmes. Hydrogen perfectly fits the characteristics to become one of the main actors in many industrial sectors to reduce the emission of polluting gases in hard-to-abate sectors. In this framework, hydrogen must be produced through zero-impact technologies. Alkaline water electrolysis is the most widespread technology to produce green hydrogen, and through its CFD modelling it is possible to accurately simulate the behaviour of these components and enhance their performance. In this study, two three-dimensional models have been created representing two types of alkaline electrolysis cell: the first one is a standard laboratory configuration (wide-gap), the second one is a zero-gap type. Both models are based on a two-phase model (liquid: water and potassium hydroxide electrolyte, gas: hydrogen and oxygen) using a Euler-Euler approach to describe the gas bubble flow. With these models it has been possible to investigate how temperature and electrolyte flow rate affect the production of hydrogen, with particular emphasis on the pressure effect. Increasing the pressure at which hydrogen is produced could mean a significant reduction in storage compression costs, giving new horizons to this technology.
Impact of hydrogen blending on a real-world gas distribution network with a non-uniform elevation profile
Authors: Francesconi M , Guzzo G , Neri M , Marmorini M , Carcasci C
Published: December 2024

The ongoing energy transition, characterized by the increasing integration of renewable energy sources, has amplified the demand for hydrogen as a clean energy carrier. Hydrogen requires not only efficient generation but also effective distribution. Utilizing the extensive natural gas infrastructure offers a practical solution, leveraging its widespread network and cost-effective capacity to transport large volumes of gas. Nevertheless, hydrogen blending causes significant alterations in gas quality and the fluid dynamic behavior of the whole network. This study aims to investigate the effects of hydrogen blending on the main fluid dynamic parameters, flow rate balancing, and gas quality in a multi-pressure gas distribution network with a non-uniform elevation profile. The proposed real test case leverages and validates the actual geometrical, altitudinal, and topological characteristics. Steady-state simulations with different mixtures, ranging from 2% to 20% hydrogen by volume, were performed. The results show that in the medium-pressure network, it is possible to operate with hydrogen mixtures while remaining within the normative fluid dynamic limits, and a marginal benefit can even be obtained on the minimum recorded pressure. In low-pressure subnetworks, the margin of pressure safety is greatly reduced, and with off-peak demand, even small elevation changes establish the most critical withdrawal node. However, due to the different distribution of gas flows, a decrease in maximum velocity is observed. The analysis shows some new fluid dynamic aspects to be considered to support feasibility analyses for hydrogen blending on gas infrastructure laid over areas with uneven elevations.
Performance Evaluation of Hydrogen-Powered Internal Combustion Engine City Bus for the Urban Mobility of Bologna, Italy
Authors: Brancaleoni Pier Paolo , Corti Enrico , Ravaglioli Vittorio , Moro Davide , Silvagni Giacomo , Brusa Alessandro , Cavina Nicolò , Ponti Fabrizio
Published: December 2024

Due to its geographical features, northern Italy is particularly prone to poor urban air quality and air pollution. Vehicular emissions are one of the main sources of pollutants and greenhouse gases emissions. Reducing the number of vehicles and promoting collective urban sustainable mobility represent the best solution to cut-down emissions from the transport sector in urban contexts. Among the possible solutions, hydrogen-fuelled internal combustion engines are particularly attractive, due to the interesting compromise between low manufacturing cost and low emissions (CO2 is absent, while other pollutants can be easily kept under control). Despite the lack of a distribution network, the operational path of hydrogen urban buses is known a priori, allowing them to operate without relying extensively on distribution infrastructure. This study presents a performance evaluation of a hydrogen-powered internal combustion engine bus within the metropolitan area of Bologna, Italy, assessed on two distinct routes representing diverse typical operating conditions. Through a dedicated virtual vehicle model, the performance of the bus is assessed in terms of fuel efficiency and NOx emissions. Additionally, a sensitivity analysis is conducted to evaluate the impact of variations in both the bus weight and passenger load on its performance metrics. The findings of the present study provide valuable insights into the sustainability of hydrogen buses for urban contexts, paving the way for their adoption as a sustainable transport solution.
Accuracy estimation of a CFD multiphysics approach to study a mixed parallel and serpentine flow channels PEM fuel cell
Authors: D’Alessio Emanuele , van Ginkel Rob M. , Donato Filippo , Agati Giuliano , Borello Domenico
Published: December 2024

This study presents a comprehensive analysis of a 50 cm2 fuel cell with mixed parallel and serpentine flow channels using Computational Fluid Dynamics modelling. Through rigorous validation against experimental measurements, the numerical model ensures accuracy in capturing convective and diffusive fluid flows, thermodynamic, and electrochemical phenomena and their mutual interaction. The study discusses a systematic procedure for achieving model convergence and identifies key parameters influencing the fitting of numerical polarization curves with experimental data. Operating within a temperature of 333 K, at atmospheric pressure, with a relative humidity of 100% for both the anode and cathode, the model offers crucial insights for advancing our understanding of fuel cell operation and guiding the development of more efficient and reliable technologies. In the activation region, reference exchange current densities and charge transfer coefficients were proved to play a significant role in reproducing the PEM fuel cell behaviour. Increasing the exchange current densities raises the voltage output in the activation polarization region while charge transfer coefficients affect the slope of the curve. In the ohmic region, a proton conduction coefficient of 1.84 and a contact resistance between gas diffusion layers and bipolar plates equal to 4.03e-7 Ω·m2 were used to fit the experimental polarization curve. After the tuning process, the numerical curve closely matches the experimental one with a maximum relative error of 2.40% and an R2 value of 0.9848. Moreover, a detailed analysis of the internal distribution of key variables was conducted for a specific point on the polarization curve (0.25 A/cm2). This analysis provided significant insights into the complex interplay of fluid dynamics, heat transfer, and electrochemical processes. Specifically, it was observed how the flow distribution, pressure drop, and reactant concentrations within the fuel cell channels and gas diffusion layers affect overall performance, highlighting the crucial role of convection and diffusion in reactant transport and the importance of managing heat for optimal cell operation.
Unsteady phenomena in the exhaust circuit of turbocharged automotive engines
Authors: Onnis Federico , Usai Vittorio , Marelli Silvia
Published: December 2024

The application of turbocharging is still a crucial aspect, especially in hydrogen engines where ultra-lean combustion is required, to mitigate abnormal combustion and NOx formation. The adoption of advanced turbocharging systems results in an increased complexity of the engine intake and exhaust circuits and requires a proper design to optimize unsteady flow phenomena.

Therefore, it is essential to understand the performance of the single elements of the turbocharging circuit and their interactions when coupled.

A specific test rig for components of propulsion system is operating at the University of Genoa, where investigations under steady, transient and pulsating flow conditions can be performed. This study presents the results of experimental investigations conducted under unsteady flow conditions on the exhaust manifold of an internal combustion engine, specifically examining unsteady phenomena in the turbine inlet circuit.

The pulsating flow is generated by a motor-driven cylinder head. Pressure signals recorded in different sections of the exhaust circuit located in the inlet and outlet turbine circuit are analysed in detail, quantifying also the effects of flow unsteadiness using parameters proposed in the open literature. In particular in the following article, the degree of instability, the Strouhal number and the reduced frequency are considered to quantify the impact of unsteady phenomena within the system for the considered lengths.

Understanding the unsteadiness within engine circuits is crucial for determining the appropriate modeling approach for system simulation. This work highlights that a quasi-steady flow model is appropriate for modeling individual branches for the exhaust manifold, while a wave action model is necessary for the entire exhaust circuit.
Virtual development of a multi-cylinder hydrogen spark ignition engine operating at lean burn conditions
Authors: Ugliano Emanuele , Bozza Fabio , Teodosio Luigi
Published: December 2024

Propulsion systems for automotive applications are facing the issues related to the stringent noxious emission and CO2 regulations which are driving the manufacturer and the researchers to the development of innovative powertrains. Among the different solutions, relevant efforts are being directed towards the decarbonisation of internal combustion engines (ICEs). In this scenario, the hydrogen, particularly the green one obtained through the water electrolysis using renewable energy sources, is emerging as a promising fuel for a future sustainable mobility. In this work, a multi-cylinder hydrogen Spark Ignition (SI) engine conceived for automotive applications is developed and optimized to operate under ultra/lean air/hydrogen mixtures. In particular, a 3-cylinder turbocharged hydrogen SI engine is virtually developed through a 0D/1D model, starting from a naturally aspirated single-cylinder SI unit; the latter is properly validated with experiments and 3D CFD outcomes in a previous authors’ activity. A fractal model is used for combustion modelling, coupled to a user-defined turbulence sub-model. The thermo-diffusive instability sub-model, based on Howarth theory, is integrated into the combustion model to correctly simulate the hydrogen engine operation at ultra/lean mixtures. In addition, the knock onset is evaluated with a Tabulated Kinetic of Ignition (TKI) approach, requiring a pre-computation of the auto-ignition delay times at varying the thermodynamic conditions. The main aim of the work is to forecast the hydrogen engine operation under full load and ultra-lean conditions, analysing performance, efficiency and NOx emissions at the knock limit. Subsequently, an optimization of the engine operation is carried out exploring different compression ratios, air/fuel proportions (lambda values) and water-to-fuel ratios. The objective of the initial optimisation is to optimise efficiency while respecting the safety constraint on the occurrence of shocks. Comparison with the base case, in which the maximum value is 35.6%, reveals an increase of 1.98% with CR equal to 13. However, in the case of the high-speed analysis, there is a decrease compared to the base case. The second analysis shows that the maximum lambda value that meets the imposed BMEP target is 2.1, thus minimising the NOx emissions of a multi-cylinder hydrogen engine under all conditions. A final analysis was conducted to study the impact of water injection on NOx for fixed rpm.
Alternative Propulsion Systems and Low/Zero Carbon Fuels for Different Marine Vessels
Authors: Perna A. , Cappiello A. , Di Cicco G. , Lanni D. , Rinauro B. , Romano F. , Minutillo M.
Published: December 2024

In 2022, shipping was responsible for around 706 million tonnes of carbon dioxide emissions, up 5% from 2020 and back to 2017-2018 levels. To accelerate the energy transition and reduce emissions in this sector, the International Maritime Organization (IMO) has set ambitious goals requiring all stakeholders’ radical actions. Several solutions have been proposed such as cruise speed reduction, on-board installation of a Carbon Capture and Storage system, use of low/zero carbon fuels in conventional internal combustion engines, and introduction or replacement of the main and auxiliary engines with novel technologies. Thanks to their high energy conversion efficiency, and reduced environmental impact, the interest in fuel cell-based systems for shipping propulsion has been rising in the last few years. In this work, the replacement of fossil fuel-based marine engines with fuel cell technology is analysed from technical and environmental points of view. A preliminary technical assessment, aiming at defining different powertrain configurations, is performed by starting from the characterization of the selected ships, in terms of installed power, navigation routes, and load profiles. The feasibility of the proposed solutions is evaluated by considering the fuel consumption and the emissions avoided with respect to the conventional solutions.
An Overview about FPT Industrial Telematic Service for Monitoring and Diagnostic purposes. First approaches to Signal Logger Data from Heavy-Duty Commercial Vehicles
Authors: D’Agostino Valerio , Verdone Gianmarco , Cardone Massimo
Published: December 2024

One of several services of FPT Industrial Customer Service team is Monitoring&Diagnostic of engines through telematic. FPT Industrial S.p.A. is an Italian brand of Iveco Group dedicated to the design, production, and sale of powertrains and solutions for on- and off-road applications. The focus of this study is on heavy-duty on-road vehicles. They are part of an Iveco vehicle fleet powered by FPT engines equipped with telematic devices. The telematic data have been used for energy efficiency and driving style relations and analysis; after every key-on event the acquisition and transmission of data start. An on-board device, called Telematics Mobile Diagnostic (TMD), is responsible for sending this data flow from Dongle, connected to the OBD port, to control room with a frequency of 1 Hz. The large amount of data will be useful for interesting analysis of drivers’ real use: an investigation about their behaviors and missions has been carried out. Therefore, the main purpose of the work is to keep track of vehicle efficiency, energy spent to distance travelled ratio (kWh/km). Hence, a correlation between the dynamicity of the drive, through Driving Scores and Pearson’s coefficient, and consumption has been proposed. The outcome is a characterization of the missions with few indexes, inferred by telematic data, without consulting any plot.
Mechanical design of a quartz oxy-combustion chamber: chemical-physical analysis of the combustion phenomenon
Authors: Brenda Raho , Marco Milanese , Arturo de Risi , Gianpiero Colangelo
Published: December 2024

Climate change and environmental degradation are huge threats to Europe and to the world. To overcome these problems, there are a series of government proposals with the aim of achieving carbon neutrality, or, at least, reducing net greenhouse gas emissions up to 55% by 2030. The greenhouse effect is caused by a high concentration of harmful emissions, especially CO2, in the atmosphere; hence, it is imperative to minimize their amount. Because of this, there is a strong effort to research suitable operational methods and secure useful technological advancements. A valid solution to actively contribute to the global objectives for achieving carbon neutrality is the oxy-combustion process, i.e., combustion in an oxygen atmosphere. This process can be considered as “clean” combustion because it does not produce pollutants such as NOx and SOx but only CO2 and steam. In addition, the production of essentially pure CO2 makes possible subsequent operations of carbon sequestration. The proposed paper describes the mechanical design and construction of a lab-scale oxy-fuel chamber, entirely made of quartz. The chosen material makes it possible to visualize, analyze and study the combustion process inside the chamber through imaging techniques by investigating its chemical and physical characteristics.
State of the art and working fluids for high temperature heat pumps
Authors: Di Salvatore F , Mauro A W , Pelella F , Viscito L
Published: December 2024

In the current framework of the European policy that pushes toward the ecological transition by promoting the use of low GWP refrigerants and the system electrification, high temperature heat pumps (HTHPs) can be considered as an important technology with huge applicative potential. Their capacity to boost the heat quality from lower to higher temperatures, in fact, makes these machines very interesting across numerous domains. On this regard, this paper presents a comprehensive critical review of the state of the art for applications and working fluids related to high temperature heat pumps. The focus is on the analysis of the heat pump thermodynamic cycles and performance, possible suitable refrigerants, operating source and sink temperatures, potential applications and related technical challenges. More than 25 scientific papers are reviewed, showing large application potential in the food, paper, metal and chemical industries, together with the residential sector.
Exploiting Deep Learning for the Optimization of Transonic Centrifugal Impellers
Authors: Pela Alessandro , Marconcini Michele , Arnone Andrea , Agnolucci Andrea , Toni Lorenzo , Valente Roberto , Belardini Elisabetta
Published: December 2024

Artificial intelligence is a powerful tool across numerous scientific disciplines. Within turbomachinery, the application of Artificial Neural Networks (ANNs) stands out for its capacity to facilitate the optimization of stage components. ANNs can reveal complex nonlinear relationships between geometric features, which can pose challenges even for experienced designers to discern. This paper explores impeller optimization, leveraging the capabilities of ANNs. Thanks to a parameterization scheme tailored for 3D geometries, neural network training utilizes a richly diverse database of geometric configurations. The investigation of the resulting Pareto front results in the discovery of highly efficient solutions across diverse geometrical configurations. Crucially, the utilization of ANNs yields multiple solutions with comparable performance, affording designers the flexibility to select solutions tailored to specific requirements, such as achieving a balance between maximum efficiency and operating range. Notably, the analysis of flow fields reveals how artificial intelligence uncovers diverse solutions to maximize efficiency. The paper introduces three optimized solutions for a high-Mach number impeller, each highlighting different blade geometries that impact flow fields and blade loadings within the transonic region. While sharing certain geometrical features, the three cases demonstrate notable variations in blade design. Performance is evaluated by analyzing the polytropic efficiency, work coefficient, and polytropic head coefficient curves, which allow a comparative evaluation of the maximum efficiency and operating range of the three impeller models.
Aerodynamic reverse engineering design using fuzzy logic
Authors: Dambrosio Lorenzo , Domenico Naschetti , Pascazio Giuseppe
Published: December 2024

The goal of this paper is to create a solid and efficient design method leveraging a fuzzy logic algorithm. This fuzzy logic system presents a non-analytical structure, facilitating the management of numerical mappings and data obtained by measurements and analytical relations, while also utilising the knowledge distributed in previous projects. Employing this information, the fuzzy logic algorithm can quickly generate an initial design, serving as a solid foundation for further optimisation. This first-glance solution can be leveraged to generate a few other designs in its neighbourhood that will then constitute the Fuzzy Logic Base of rules for further optimisation. The proposed method’s effectiveness and efficiency are demonstrated through the design of a nozzle for both subsonic and transonic flow conditions.
Weld seam positioning method for structural reinforcement based on 3D point cloud
Authors: Li Xiaohui , Qin Gaoe
Published: December 2024

Machine vision technology assists welding robot weld positioning, which can significantly improve welding accuracy and efficiency. This paper delves into a 3D point cloud-based positioning technique specifically tailored for structural reinforcement welds, utilizing the high-precision 3D structured light camera to get 3D point cloud data from the surface of the reinforcement structures, subsequently conducting a comprehensive analysis of the weld’s geometric characteristics. When the weld seam position can be directly collected, the side plate plane and the bottom plate plane of the reinforcement can be divided by the random sample consensus method. The weld points with rich curvature characteristics can be quickly and reliably selected according to the plane constraint. When the weld position cannot be measured directly, the prediction of the weld position is realized by extracting the edge of the upper surface of the reinforcing rib in the depth map and combining the plane normal vector of the base plate and the point laser correction vector. The experimental results show that this method can accurately locate the weld seam with high accuracy in both working scenarios.
Design of meter module assembly line based on automation
Authors: Liu Yuluan , Lin Jingxiang , Wei Lilong
Published: December 2024

This paper designs an automated assembly and binding device for power meters and communication modules, aiming to optimize the metering asset management process. The device ensures assembly quality and reduces manual intervention through full visual guidance and precise servo control. The design includes two automated assembly line solutions, realizing 36-second and 20-second assembly beats, respectively, which significantly improves production efficiency. Advanced automation technologies, such as 3D visual recognition, automatic screw guns, labeling flyers, etc., are used in major processes to ensure high efficiency and accuracy of the assembly process. In addition, the material flow turn design is flexible with a caching function, which enhances the continuity of the production line. Through the combination of multifunctional robots and intelligent modules, efficient and disordered gripping and assembling are realized, ensuring product quality and work stability. The research in this paper provides a practical solution for the automated assembly of meter modules and promotes the intelligent development of the electric power industry.
Design of automobile gearbox measurement and control system based on ARM7
Authors: Zhang Li , Huang Jinlin , Cao Guanghua
Published: December 2024

Aiming at the large energy loss and shortcomings of low control efficiency of the current automobile gearbox test bench, the antomobile gearbox measurement and control system are designed through the mehtod of DC energy regeneration and AC power generation. The JZ-type sensor is selected which is magnetoelectric with phase difference. The energy feedback unit is designed by using the double bridge parallel converter circuit. The user interface is programmed by Visual C + + with ARM7 as the core. The experimental results show that the system can detect the torque and speed accurately and automatically. Then display it in real time according to the given control. The test bench runs smoothly and reliably and meets the design requirements.
An improved k-means cluster method based on partial correlation coefficient for line-transformer connectivity identification in distribution network
Authors: Fang Tao , Lou Xiyue , Diao Xinzhuang , Hu Feihu
Published: December 2024

The accurate identification of line-transformer connectivity of the distribution network is very important for load balancing and line loss management. The electric quantity data can be used to identify the relationship, but the recognition accuracy is limited. The essence of relation recognition is unsupervised classification, but as there is no direct center of mass and distance, the traditional mainstream clustering method cannot be applied. Therefore, this paper proposes an improved K-means clustering algorithm based on a partial correlation coefficient. Firstly, spectrum analysis is carried out for the collected power data of the distribution transformer and the 10 kV line, and the high-frequency component of the data is obtained by the high-pass filter. Then, the K-means clustering algorithm improved by the partial correlation coefficient is used to set the electric energy data of each line as the initial centroid. The correlation between the station area and the line is calculated by using the concept of the partial correlation coefficient, and the station area represented by the minimum line distance is assigned to the corresponding line. The results show that this method can improve the accuracy of linear relation identification based on electric quantity data.