bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Lumped-Parameter Model of a Smart Ventilation unit for nearly Zero Energy Buildings
Authors: Sedoni R , Cannistraci G , Santangelo P E , Angeli D , Romani M , Fioravanti L 
Published: December 2023

Abstract
In the present work, a simple model of a ventilation unit used for residential purposes is proposed, which was developed by means of MATLAB Simulink and the Simscape toolbox, also including the Moist Air and Two-Phase fluid libraries. This study falls in the realm of air conditioning in nearly Zero Energy Buildings. The model presented here is focused mostly on the aeraulic system. A parametric analysis of various installation conditions was conducted to assess and enhance the combined heat pump and the air distribution system performance, under various operating conditions. Therefore, the overall approach included several parameters, such as outdoor and indoor air temperature, humidity, static pressure, pressure drop in the intake and the distribution ducts, and filter fouling. The model serves as a predictive tool to evaluate the effectiveness of the whole system, in both design and off-design conditions; notably, critical conditions are emphasized, which are associated to severe fouling conditions, making the use of an additional fan ineffective.
Preliminary analysis of refilling cold-adsorbed hydrogen tanks
Authors: Melideo D. , Ferrari L. , Taddei Pardelli P. 
Published: December 2023

Abstract
The effective storage of hydrogen is a critical challenge that needs to be overcome for it to become a widely used and clean energy source. Various methods exist for storing hydrogen, including compression at high pressures, liquefaction through extreme cooling (i.e. -253 °C), and storage with chemical compounds. Each method has its own advantages and disadvantages. MAST3RBoost (Maturing the Production Standards of Ultraporous Structures for High Density Hydrogen Storage Bank Operating on Swinging Temperatures and Low Compression) is a European funded Project aiming to establish a reliable benchmark for cold-adsorbed H2 storage (CAH2) at low compression levels (100 bar or below). This is achieved through the development of advanced ultraporous materials suitable for mobility applications, such as hydrogen-powered vehicles used in road, railway, air, and water transportation. The MAST3RBoost Project utilizes cutting-edge materials, including Activated Carbons (ACs) and high-density MOFs (Metal-organic Frameworks), which are enhanced by Machine Learning techniques. By harnessing these materials, the project seeks to create a groundbreaking path towards meeting industry goals. The project aims to develop the world’s first adsorption-based demonstrator at a significant kg-scale. To support the design of the storage tank, the project employs Computational Fluid Dynamics (CFD) software, which allows for numerical investigations. In this paper, a preliminary analysis of the tank refilling process is presented, with a focus on the impact of the effect of the tank and hydrogen temperatures on quantity of hydrogen adsorbed.
Pumps as turbines for pumped hydro energy storage systems - A small-size case study
Authors: Licheri Fabio , Petrollese Mario , Cocco Daniele , Cambuli Francesco 
Published: December 2023

Abstract
Pumped Hydro Energy Storage (PHES) technology has been used since early 1890s and is, nowadays, a consolidated and commercially mature technology. PHES systems allow energy to be stored by pumping water from a lower-to a higher-level reservoir. Subsequently, this energy can be released through a turbine placed in a penstock, which connects the two reservoirs, to produce energy. Although these plants have historically been employed at large power scales (in the order of hundreds of MW), in recent years, micro- and small-scale plants are becoming more interesting, due to their possibility of being integrated with renewable energy systems (RES) used in autonomous island grids. Capital costs associated with hydraulic machines used in PHES systems represent the most critical economic factor, which can be mitigated by using commercial centrifugal pumps in reverse mode (Pumps as Turbines, PATs) in place of small hydro turbines. These expected economic benefits must be weighed in each specific case study, with some drawbacks related to the use of PATs, mainly associated to a lower round-trip efficiency with respect to specifically designed pumps and turbines.
In this work, a small-scale PHES plant has been studied coupled to an existent photovoltaic system for the integration in the electric grid of a small island in Southern Italy. Two different PHES outlines have been compared based on techno-economic considerations. The former is a typical PHES system composed of both pumps and a turbine, while the latter uses only an array of parallel pumps which work also in reverse mode. The analysis demonstrates the feasibility of integrating a photovoltaic and PHES plant, which results in a lower cost of electricity production, while PHES performance in the PAT-based outline results penalized by the lower efficiency of PATs with respect to the hydraulic turbine.
Energy analysis of a hybrid electro-hydraulic system for efficient mobile hydraulics
Authors: Padovani D , Rundo M , Fresia P , Altare G 
Published: December 2023

Abstract
Energy efficiency plays a significant role in mobile hydraulics due to the high amount of carbon dioxide and pollutants being released into the atmosphere. Efficiency improvements are urgently needed, so the electrification of mobile hydraulics represents a fantastic opportunity in this regard. This approach leads to electro-hydraulic systems that remove functional flow throttling in control valves and enable energy recovery. Fuels savings were already demonstrated in simulation, but the literature does not offer entire energy analyses of these electro-hydraulic solutions. This limitation prevents complete system-level comprehension and does not give enough insight to pinpoint areas for further efficiency improvements. Thus, this paper focuses on a hybrid system for excavators based on electro-hydraulic drives that is compared against the original valve-controlled layout. The objective is to quantify the energy flows insight the excavator during relevant operations and highlight the resulting energy losses. The outcomes confirm that electro-hydraulic solutions are suitable for a low-carbon economy. They indicate hydraulic actuators, speed-controlled pumps, and electric motors as the critical components for further energy efficiency enhancement excluding the combustion engine.
Design considerations about the hydromechanical transmission IC2OC
Authors: Rossetti A , Andretta N , Macor A 
Published: December 2023

Abstract
The hydromechanical transmission IC2OC operates as an Input Coupled transmission at low speeds and as an Output Coupled transmission at high speeds; a series of clutches allows the shift between two layouts. In this way the transmission speed range can be almost doubled.
The design of this transmission requires the full mechanical speed value for both basic layouts. Since these values heavily influence transmission performance, their choice must be made carefully.
In this paper two choice criteria for these two speeds are proposed and discussed: the first one refers to the optimal choice for each basic layout; the second sets these speeds in correspondence with the speed of the maximum energy processed in a working cycle.
The effectiveness of these two criteria, applied to an off-road vehicle transmission, demonstrates that the former guarantees greater efficiency than the latter, despite its good assumptions.
Energy analysis of a hydrogen integrated system in the residential sector
Authors: Mennilli Francesca , Jin Lingkang , Rossi Mosè , Mugnini Alice , Comodi Gabriele 
Published: December 2023

Abstract
Nowadays, buildings are responsible for almost 40% of global energy consumption, which is addressed by thermal (e.g., heating, cooling, and hot water) and electric (e.g., lighting and household appliances) loads. To meet the residential energy demand and, at the same time, ensure the decarbonisation of the energy infrastructure, hydrogen-based cogeneration systems might represent a viable solution. This work aims at evaluating the performance of a green hydrogen integrated system consisting of a Proton Exchange Membrane (PEM) electrolyser, hydrogen storage tanks, and a PEM fuel cell to meet both the electricity and, partially, the thermal energy demands of a condominium located in the center of Italy. The analysis considers a single energy scenario in which a Photovoltaic (PV) plant installed on the roof is directly connected with the hydrogen integrated system without any withdrawal from the national grid (e.g., off-grid operation mode). Results showed that, during the year, the user is completely self-sufficient from the electricity demand point of view. Furthermore, 22% of the thermal need can be satisfied through the fuel cell cogeneration system.
Comparison between optimal refueling infrastructures for zero emission waste transportation vehicles in Valle Camonica
Authors: Vincenti Ferdinando , Bontempi Manuel , Poetini Bruno , Furlanetto Dario , Valenti Gianluca 
Published: December 2023

Abstract
The aim of this work is to conduct a comprehensive and fair comparison between fleets of vehicles powered by different technologies, namely electricity, compressed hydrogen, and liquid hydrogen. The study followed a well-defined methodology, starting with the development of a mixed-integer linear programming (MILP) model using MATLAB and the YALMIP toolbox. The primary objective of the model is to minimize the total annual cost associated with the infrastructure required for refuelling the fleet of zero-emission vehicles. The battery electric vehicle refuelling infrastructure is used as a benchmark, with a total annual cost of around 200000 €/y. The compressed hydrogen and liquid hydrogen infrastructure are comprehensive of a solar photovoltaic field. The hydrogen refuelling facility are analysed varying the price of the electricity. In the most profitable configuration, the compressed hydrogen refuelling facility cost around 320000 €/y and for the liquid hydrogen 480000 €/y. The sensitivity analysis, performed varying the cost of electricity, shows that it is never convenient to use hydrogen vehicles even in condition of high electricity prices. When it is possible to use electric vehicles and there are no constraints related to payload, range or refueling logistics they must be employed, as they are the most cost-effective solution to cancel the vehicles emissions.
Hydrogen production by water photo-sonolysis: a modal approach to enhance the ultrasonic acoustic field in the solution
Authors: Domenighini P. , Gambelli A.M. , Rossi F , Cotana F. 
Published: December 2023

Abstract
Water photo-sonolysis is considered one of the most innovative ways of hydrogen production. Cited by the Italian strategy on hydrogen research as a promising field for innovation research, it consists of the coupling work of solar-light electromagnetic waves and mechanical ultrasonic waves to induce water splitting. Water photolysis requires catalysts to be performed and optimized, whereas ultrasound sonolysis acts independently. In the state of the art, it was experimentally demonstrated that the rates of hydrogen production by sonolysis rise according to resonance peaks of the solution in function of ultrasound wavelength. To enhance the effects of the ultrasound, the resonance of the solution can be geometrically achieved by acoustic modal analysis of a set of possible solution volumes. According to the geometry of the photo-sono reactor at the lab scale, the shape of the tested solution volumes is cylindrical. The modal analysis was led in a Matlab environment considering the cylindrical volume’s geometry and the fluid’s physical properties. To check the reliability of the simulated results, pressure measurements were led at the lab scale on the simulated water volumes by means of a hydrophone at a significant number of points.
Multi-physics model development and application to real-case alkaline electrolyzer
Authors: Dreoni M , Balduzzi F , Ferro F M , Fagioli G , Panichi K , Ferrara G , Bianchini A 
Published: December 2023

Abstract
The realization of mathematical, multi-physics models for alkaline electrolyzers is crucial for advancing this technology. Lumped parameter models offer shorter simulation times, compared with other approaches, and practical industrial applications. If electrochemical models provide the polarization curve, the hydrogen production rate, and the device efficiency, thermal models solve the equations involving the electrolyte temperature. With a coupled approach, the two models can be linked together by considering the device voltage as temperature dependent. Despite the relevance of such models, few instances of their direct application on existing electrolyzers can be found in the literature, and combined electrochemical-thermal simulations are rare.
This study presents a multi-physics model applied on an alkaline electrolyzer and validated against measurements acquired on a dedicated experimental test bench.
The physics-based model accurately predicts the polarization curve, exhibiting a high precision match with experimental data. Additionally, it identifies material or geometrical imperfections in the electrolyzer, allowing for optimization in the design phase. The thermal model successfully converges to the desired electrolyte temperature of 72 °C under stationary conditions. Additional transient simulations demonstrate an average deviation of only 0.25% compared to the measured temperature trend. Finally, a sensitivity analysis explores the coupling of the electrolyzer with a wind turbine under different wind conditions.
The study showcases the effectiveness of the coupled electrochemical-thermal model in predicting electrolyzer performance, with a direct application to a wind turbine power output.
Experimental methodology for the characterization of a hydrogen-fuelled Pressure Gain Combustor
Authors: Tempesti C , Romani L , Ciampolini M , Hakuri O , Ciccateri F , Ferrara G 
Published: December 2023

Abstract
Gas turbines have been a key technology in many industrial sectors for over 50 years and they will continue to play a crucial role in the energetic scenario. Nevertheless, these systems are approaching their efficiency limits and performance improvements are becoming increasingly difficult to achieve. In this context, Pressure Gain Combustion (PGC) has emerged as a promising technology: replacing the isobaric combustion with a quasi-isochoric process creates a rise in total pressure across the combustion chamber, enhancing their potential performances. However, it is a complex process influenced by combustion chemistry, heat transfer, and fluid dynamics, and its unsteadiness increases the complexity of measurement campaigns. Thus, several challenges still need to be addressed for its development.
This paper shows the experimental methodology followed to characterize an innovative deflagrative-based PGC fuelled with 100% hydrogen. Dynamic pressure sensors were installed inside, upstream, and downstream of the combustion chamber and acquired at a high frequency (1 MHz) to describe in detail the process.
Downstream the combustor, an orifice simulated the pressure drop across the turbine. Different fuel pressure has been tested, varying the operating parameters and the position of the pressure sensors inside the chamber. For each configuration, a detailed analysis of the mean pressure trends and cycle-to-cycle variation was carried out and will help optimize the system in the following tasks of the project. The experimental methodology described can be used to better investigate the physics of Pressure Gain Combustors and allow complete exploitation of their potentiality in terms of work extracted, resource consumption, and pollutant emission.
Fuel Cell Hybrid Electric Vehicles: Fuel Cell experimental characterization and modeling towards the development of a Hardware-in-the-Loop platform for advanced powertrain design
Authors: Bartolucci Lorenzo , Cennamo Edoardo , Cordiner Stefano , Donnini Marco , Grattarola Federico , Mulone Vincenzo , Pasqualini Ferdinando 
Published: December 2023

Abstract
Greenhouse gas emissions in transport sector is a critical issue, with automobiles and trucks responsible for emitting nearly 5.9Gt of CO2. Addressing climate change is then of paramount importance to avoid irreversible consequences. Advanced technologies are being developed to achieve this goal. Among them, Fuel Cell Hybrid Electric Vehicles (FCHEVs) offer several benefits, including wide applicability and range, short refueling times, and no tailpipe emissions, that can only be exploited if optimizing their design. This requires time and cost-consuming iterative processes, and Digital Twins (DTs) and Hardware-in-the-Loop (HIL) test benches are then gaining importance with respect to prototype manufacturing. In this study, the basis for a HIL application is posed, including a 2kW Fuel Cell (FC) and a bidirectional DC power supply used to emulate the electric motor. After characterizing the FC, DTs have been calibrated and validated through experimental tests; DTs have then been included into a FCHEV microcar model and its performances have been analyzed. Results have shown high accuracy in representing the real FC performance, with a 5% maximum error from the energy standpoint. Moreover, HIL approach has been proved to be fundamental for catching peculiar transient phenomena, significantly impacting on the powertrain design and performance.
Hydrogen volumetric fraction effects on HCNG refuelling station CAPEX
Authors: Sgaramella Antonio , Ciancio Alessandro , Mojtahed Ali 
Published: December 2023

Abstract
Greening the transport sector is crucial for the achievement of the ambitious decarbonisation goals set by the Conference of the Parties (COP21) Paris agreement to keep global warming “well below 2 degrees Celsius above preindustrial levels, and to pursue efforts to limit the temperature increase even further to 1.5 degrees Celsius”. Battery electric vehicles and hydrogen fuel cell electric vehicles will play a key role in the reduction of greenhouse gas emissions in the road mobility. Nonetheless, those technologies still need to face some technological challenges. Hence, hydrogen enriched natural gas (HCNG) can play an important role as bridging technology. This study envisages the upgrade of an existing compressed natural gas (CNG) refuelling station (RS) in HCNG-RS. Particularly, an analysis regarding the impact of different hydrogen volumetric fractions in the blend on the total CAPEX of the HCNG refuelling station is carried out, by evaluating the HCNG fill-up demands for a proper refuelling station sizing. The proposed HCNG refuelling station layout foresee the on-site hydrogen production by means of an electrolyser fed by PV energy. Each component of the station has been adequately sized based on the resulting peak HCNG refuelling demand. The highest CAPEX value is recorded for the 30%vol. HCNG, amounting up to 3.52 M€.
A potential coupling of reforming and electrolysis for producing renewable hydrogen from landfill gas
Authors: Massulli Axel Riccardo , Mojtahed Ali 
Published: December 2023

Abstract
Organic sold waste disposed of in landfills undergoes a mostly anaerobic process which generates a mixture of methane (CH4), carbon dioxide (CO2) and other various gases such as nitrogen, oxygen, sulphides, and non-methane organic compounds (NMOC), known as landfill gas (LFG). Being composed mostly of CH4 and CO2, landfill gas is a potent greenhouse gas (GHG). As a result, various waste treatment interventions are required to minimize the potential catastrophic damage to the environment from direct greenhouse gas emissions from landfills. One effective solution is combustion to generate electricity exploiting methane’s flammability properties. Biomass-based power plants have been present for decades. However, the combustion process is accompanied by a remarkable production of thermal energy which is typically not exploited and therefore lost to the ambient. The current work presents an energetic solution to manage organic waste by employing green hydrogen production. To do so, a hybrid layout based on a cogeneration unit (CHP) fed with landfill gas is considered. The electrical power produced by the CHP is used to produce hydrogen through low-temperature water electrolysis. Furthermore, due to the significant waste heat available in the system, excess thermal power is employed for the methane steam reforming process through a heat recovery section. Hydrogen produced from the reforming section is green since the input is from landfill gas, which is considered renewable. The levelized cost of hydrogen produced from such a hybrid layout is obtained and compared with non-renewable sources in this field. In addition, the annual H2 production rate is calculated for a capacity factor equal to 70%. The results show an annual Hydrogen production of about 167 t/y. LCOH at the stack of about 2 €/kg is reported.
Decarbonization of methanol production - Techno-economic analysis of Power-to-Fuel process in a Hydrogen Valley
Authors: Ciancio Alessandro , Mojtahed Ali , Sgaramella Antonio 
Published: December 2023

Abstract
The European Union set the decarbonization goals and green hydrogen can play a crucial role for the greenhouse gas emission reduction. Hydrogen Valleys can be pivotal for the hydrogen economy, by integrating the local green hydrogen (H2) production into the industrial sector. Thus, by means of the Power-to-Fuel approach H2 can be exploited for the synthetic fuel. This study aims at investigating the synthetic methanol (CH3OH) production process with recycled carbon dioxide (CO2) and green hydrogen in a Hydrogen Valley. Currently, industrial-scale methanol is produced from natural gas, where methane (CH4) reacts with H2O at high temperature and pressure. The green hydrogen can improve the long-term sustainability of this process, making the green methanol exploitable in the hard-to-abate sectors. Therefore, the purpose of this research is to evaluate a techno-economic analysis of various scenarios for the synthetic methanol production process in the Hydrogen Valley. This analysis has been carried out for different time periods: 2020, 2030, and 2050. The outcomes show that the current Levelized Cost of Methanol production ranges between 158.41 €/MWh and 227.69 €/MWh. In the long term, those values decrease to a range of 72.01 €/MWh to 97.05 €/MWh. The most suitable RES capacity scenarios have been derived along with the associated global investment costs. The best scenario in the short and medium term envisages 1 MW of on-shore wind plants and 1.5 MW of photovoltaic plants with a total investment cost of 4.10 M€ by 2020. In the long term, the best scenario foresees 2 MW of photovoltaic and 0.5 MW of on-shore wind. In so doing the 2050 investment cost is reduced to 1.62 M€.