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The paper proposes a combined approach between numerical modeling and experimental measurements for the analysis of a cogeneration system based on the reaction of liquid aluminum and water steam. Scrap aluminum is used for hydrogen production and the primary one is employed as an energy carrier to transport the energy from the alumina reduction system to the site of the suggested plant. The analysis focuses on the liquid aluminum injection phase immediately downstream the nozzle. High frequency thermo-cameras are employed to qualitatively assess the thermal behaviour the liquid aluminum jet. Fast imaging techniques are used to capture the multiphase flow pattern of the liquid metal jet during the injection phase. The experimental results are used to validate a 2D multi-phase CFD approach. The computational fluid dynamics model of the injection phase is created and used to extend the measurements and deepen the understanding of the thermo-fluid dynamics behaviour of the system. In particular, the influence of different nozzles diameters and different injection pressures on the liquid aluminum jet is investigated. A modular approach is adopted for the domain subdivision in order to represent accurately all the geometrical features, while the volume of fluid approach is used to model the multi-phase flow distribution in the real geometry under actual operating conditions. Finally, a good agreement between the measurements and the calculations is found.

The continuous increase in primary energy demand and the decrease in the availability of fossil fuels were led to a condition of energy security concerns. In this context, hydrogen can be seen as a promising energy carriers. This paper investigated the environmental performance, through Life Cycle Assessment (LCA) methodology, of a combined production system of hydrogen and power based on aluminum combustion with water. This system is potentially able to produce the integrated generation of four energy sources: hydrogen, high temperature steam, heat and work at the turbine shaft. The LCA results indicated that the life-cycle phases that determine the main environmental impact are: liquid aluminum production, transports of liquid aluminum and electricity consumption. In addition, the major release of carbon dioxide emissions is due to the use of natural gas in the aluminum production phase. In order to determine the “greener” alternative and support the system design choices, according to the eco-design perspective, different system configurations were investigated. In particular, the reaction mechanism between first primary aluminum powder and water steam and then secondary aluminum at liquid state and water steam. The environmental comparison highlighted that the former layout increases by more than 78% compared to latter one.

Energy efficiency, which is one of the pillars of the EU's Energy Union strategy, has been proposed as a solution, namely as a highly effective pathway to improve economic competitiveness and sustainability of the European economy, lower emissions, reduce energy dependency and increase security of supply, and job creation. The paper reviews the EU strategies and policies on energy efficiency and argues that further focus should be placed on industrial energy efficiency. Despite a decline in energy consumption in recent years in industry, this sector is one of the largest users of energy in the EU. Therefore, the paper reviews the extent to which the European and national policies in the selected jurisdictions, such as Italy and the UK address energy efficiency in industry and whether there are any measures in place to promote it. Horizon 2020 ETEKINA

Copyright © 2021 The Authors..Heat recovery opportunities and total plant energy efficiency improvements need to be evaluated before manufacturing the real components when addressing the energy and economic effectiveness in industrial applications. Numerical modelling of the complete energy systems can be a key design tool in order to investigate the potential solutions to improve the performance of the considered system. In this study, a 0D/1D numerical analysis and transient system simulation analysis are adopted to investigate the energy efficiency enhancement given by the application of a heat pipe-based heat exchanger in the ceramic industry. The thermal power is recovered from the exhaust gases of the kilns used to fire the tiles. The numerical model includes all the main components of the heat recovery system: the primary side of the exhaust gases, the heat exchanger, the secondary circuit of the heat transfer fluid and the heat sink where the thermal power is exploited. Particular care is devoted to the modelling of the heat pipe-based heat exchanger and the necessary control strategy of the system; a specific model for the simulation of the secondary side pump is also accounted for in the analysis. The numerical results of the primary circuit are validated against experimental measurements carried out on the real ceramic facility. The good agreement between the numerical and experimental results demonstrates that the numerical model is an appropriate tool for investigating the energy efficiency enhancement of an industrial plant and for evaluating different configurations and solutions in order to fulfil the industry requirements. The presented work is part of HEAT PIPE TECHNOLOGY FOR THERMAL ENERGY RECOVERY IN INDUSTRIAL APPLICATIONS — ETEKINA project. The project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement N° 768772.

The paper presents the design of the experimental apparatus developed in order to analyse the performance of a prototype of a pyrolysis system for the exploitation of the plastic residues of industrial processes and the end of life tires. The small scale pilot prototype is specifically designed for carrying out an experimental campaign aimed at determining the influence of different plastic types on the yield and on the quality of the liquid oil, gas and char obtained in the pyrolysis process. The study investigates the effect of different mixture of various plastic products mainly made of polyethylene, styrene butadiene rubber, nylon and natural rubber. The prototype is equipped with a control system able to monitor the main operating parameters of the process, such as the pyrogas pressure and temperature as well as the temperature inside the reactor where the pyrolysis takes place. The monitored variables are employed for deriving correlations among the operating conditions and the yield of the pyrolysis process. Therefore, further analysis concerns experimental measurements in order to estimate the main compounds that are contained in the syngas in comparison to the different plastic wastes analysed. Finally, the emissions of the small-scale prototype are evaluated.

This paper investigates pressurised injection system for liquid aluminium for a cogeneration system based on the Al–H2O reaction. The reaction produces hydrogen and heat which is used for super-heating vapour for a steam cycle. The aluminium combustion with water generates also alumina as a byproduct; the aluminium oxide can be recycled and transformed back to aluminium. Thus, aluminium can be exploited as energy carrier in order to transport energy from the alumina recycling plant to the place where the cogeneration system is located. The water is also used in a closed loop; indeed, the amount of water produced employing the hydrogen obtained by the proposed system corresponds to the oxidizing water for the Al/H2O reaction. The development of a specific test rig designed for investigating the liquid aluminium injection is presented in this research study. The injector nozzle is investigated by means of numerical thermal and structural analysis. The calculations are compared and validated against the experimental measurements carried out on ad-hoc developed test rig. A good agreement between the numerical results and the experimental values is found and the new design of the nozzle is devised.

Circulating Tumor Cells (CTCs) can be defined as cancerous cells, which detach from a tumor and flow through the vascular or lymphatic systems. The blood flow can carry the tumor cells in another region of human body where they can become the starting point for the growth of additional metastases. Because of this behavior, in the CTCs study it is paramount to acquire new data and knowledge to understand the mechanisms that lead to the separation of the cell from the tumor as well as the major characteristics of these cells. The aim of this work is the development of an innovative therapeutic and diagnostic approach able to lead to a new medical device for removing CTCs from the peripheral blood of a patient. The main target of the approach is to detect the CTCs and separate them during a conventional extracorporeal circulation procedure, similar to that used for renal failure. In this work, the CTCs physical properties are investigated in order to explore the possible characteristics that can be exploited in an ad-hoc developed medical device to remove them from the blood flow. The CTCs physical properties are analyzed numerically, and their behavior is studied by means of CFD simulations. The preliminary numerical tests have been carried out on simple geometries in order to assess the influence of magnetic and electric fields on tumor cells’ trajectory. These results are the baseline information to develop more complicated geometries and prototypes for real operations.

A new unipolar differential logic (UDL) for the large-scale integration of amorphous In-Ga-Zn-O (aIGZO) digital circuits is proposed. Only single-threshold single-gate and aIGZO thin-film transistors are required. The proposed UDL logic gates are very insensitive to transistor parameter variations (i.e., threshold voltage, mobility, off-current, and subthreshold slope), which are inherently due to large-area low-temperature fabrication processes and operating conditions. To assess the UDL effectiveness, a wide range of parameter variations is considered: and, owing to the proposed architecture up to 1.5 $\times$ 107 UDL gates that can be integrated with a yield that is greater than 90%.

The numerical analysis of thermal and fluid dynamics behaviour of an industrial roller kiln used for manufacturing ceramic tiles is carried out and combined with the analysis of the mechanical stresses formed in the final ceramics product. The developed numerical approach is able to address the energy efficiency, the fuel consumption as well as the pollutant emissions and the quality of the final product. The model of the ceramic kiln is based on a lumped and distributed parameter model and accounts for the heat and mass transfer phenomena that take place in the real components under actual operating conditions of the systems. Models for the simulation of the different components that are used for the kiln functioning are included in the modelling, such as the burners, the fan, the valves and the control system. The numerical approach demonstrates to predict accurately the temperature distribution of both the tiles and the hot gases along the kiln length. Numerical results are validated against experimental measurements carried out on a real kiln during regular production operations. Additionally, the calculated temperature profile of the tiles is employed to predict the mechanical stresses that form in the ceramic product within the kiln. A thermomechanical model is adopted to determine the curvature and residual stresses in the tiles and particular care is devoted to the final stresses that remain at the end of the kiln since they affect the quality of product. The developed numerical approach demonstrates to be an efficient tool for investigating different control strategies to optimize the kiln thermal behaviour as well as the tile quality. On the basis of the fluid-dynamics and thermomechanical numerical approaches, a modified operating strategy for the kiln's cooling section is proposed to minimize the tiles' residual stresses and the modified cooling profile resulted to be in the operating range of the real kiln.

The paper studies the ventilated façade as a potential alternative to conventional coating technologies for the thermal insulation of building’s external walls. The ventilated façade is modeled by means of a CFD approach that accounts for the full 3D-geometry of the building, the walls thickness and materials’ thermal properties. The effects of the windows on the heat losses and in the performance of the ventilated façade are modeled in order to accurately characterize the thermal behavior of the system. The solar radiative heat transfer during two representative days of the year is considered in the analysis and a multiband thermal radiation is adopted to capture the different nature of radiative heat exchange according to the light wavelengths. The numerical approach enables to estimate the thermo-fluid dynamic behavior of the system and the temperature distribution and the velocity flow field within the air gap between the walls are addressed and their influence on the heat transfer through the building’s external walls is determined. The CFD analysis is employed to compare different configurations of the ventilated façade for improving the thermal insulation of the building; the performance of each scenario is determined in terms of electric energy and fuel consumption for the air conditioning and the heating system. Thus, the potential saving of the energy cost for ambient thermal conditioning is evaluated. The analysis investigates the effects on the energy efficiency of different geometrical features of the system such as the height of the building and the air gap thickness and theoretical correlations are derived in order to estimate the best tradeoff between the energy efficiency of the building and the investment of the ventilated façade configuration.

Modern development of electronic control systems for agricultural tractors relies on model-based design of the control software and extensive virtual testing in simulation environments, before the final field tests on the actual machines. After the definition of requirements and specifications, each step of the typical development and validation flow, which includes model-, software- and hardware-in-the-loop (MIL, SIL, HIL) simulations, addresses different specific levels of detail in the control system while sharing the same top-level requirements in terms of desired machine behavior, thus making toolchain modularity and reusability paramount to optimize the whole development effort. A further level of complexity is added by distributed architectures, where multiple electronic units (ECUs) coordinate their operation via communication over a vehicle network, requiring proper verification of the exchange of signals conveying requests, feedbacks and status information. The present work focuses on a two-unit subsystem controlling the driveline in a class of tractors equipped with a CVT transmission, connected via CAN bus network. Dedicated verification modules have been implemented in the Matlab/Simulink/Stateflow environment, which monitor the relevant physical variables in the system (e.g. clutch pressures) and the message exchange between the two units (e.g. gear request and feedback). The CAN Watcher module internally implements a "reverse control logic", directly derived from the design requirements (i.e. independently of the actual control code implementation, for proper development-validation separation) to check that the overall system behavior be coherent with the maneuver being executed; CVT Performer instead dynamically tests the compliance to performance requirements (e.g. vehicle velocity profile). Each module can seamlessly be deployed as an independent software component in MIL, SIL and HIL environments and on a (dedicated) ECU for on-field online diagnostic.

The ceramics industry is the second largest energy consuming sector in Europe. The main energy used in the ceramics industry is heat generated through burners using natural gas. The main area can be identified in three stages, the drying stage and the firing stage, and the cooling stage. The firing stage represents about 75% of the total energy cost. The roller hearth kiln technology is considered to be the most cost-effective solution for ceramic tile manufacturing. The kiln is separated into two sections, the firing stage and the cooling stage. The cooling stage generates large amounts of waste heat as the exhaust of the kiln is composed of a challenging flue gas for heat recovery. The recovery of this heat in an efficient way with no cross contamination has been achieved with a heat pipe heat exchanger (HPHE) system, which was designed, manufactured and installed on a roller hearth kiln and is presented in this paper. The heat pipe heat exchanger located next to the cooling section exhaust stack managed to recover up to 100 kW at steady state without cross contamination or excess fouling. The return on investment of the system has been evaluated at 16 months with a saving of £30,000 per year. This paper will present a deep row by row theoretical analysis of the heat pipe heat exchanger. The Computational Fluids Dynamics will also be presented to investigate the fluid dynamics within the evaporator and condenser section. Both investigations have then been validated by the experimental investigation carried out on a full-scale industrial system. The design approach used in this paper will highlight the benefits of this type of technology and provide a guideline for the design of novel heat pipe heat exchangers.

The paper proposes a numerical model for the investigation of a piston water pump under different operating conditions. In particular, the lubricating system is analysed and modelled. The study accounts for the lubrication and friction phenomena, heat transfer, multiphase fluid approach and motion simulation. A computational thermo fluid dynamics approach has been adopted to develop a numerical tool able to simulate the behaviour of the oil during the machine working phases. The CFD approach simulates the moving metal components by means of moving meshes techniques; the friction phenomenon is estimated on the basis of formulations available in literature. The numerical model evaluates the heat transfer between moving metal parts and oil during the operating phases of the system. Furthermore, the heat transfer between oil and environment is calculated, accounting for conduction through the metal crankcase walls. A multiphase fluid approach is used for the simulation of the oil and air mixing during the crank rotation. The heat transfer coefficient predicted by the CFD approach are employed in a lumped and distributed numerical model; the reliability and accuracy of the proposed numerical approach is addressed and validated against experimental results. Experimental data have been collected by means of a thermographic camera and thermocouples. Finally, the tool's predictive capabilities are addressed by simulating different working conditions.

Chitosan is used worldwide as a food supplement and it is normally obtained from animal exoskeleton, mainly crustaceans. Chitosan produced from animals reportedly causes allergic reactions, thus only the equivalent deriving from fungi is permitted in winemaking. The OIV has issued specific methods to identify the biological origin of chitosan but these proved to be laborious and time consuming. To evaluate whether stable isotope ratios analysis could be a quicker and more effective tool to identify chitosan from fungi and from other origins, the H, C, N and O isotopic ratios of 35 samples deriving from various biosynthetic pathways are here presented. The Kruskal-Wallis test showed that δ13C and δ18O of the bulk samples were the most significant parameters (p

This paper investigates the predictive capabilities of numerical simulation for addressing the actual operation of the hydraulic system of a filling machine for beverage packaging processes. The lumped and distributed parameter approach is compared to the full CFD simulation of the filling system and the accuracy of the results obtained is assessed in case of Newtonian and non-Newtonian fluids. First, the 0D-1D model of the complete hydraulic system of the machine filling process is constructed and validated against experimental measurements carried out using water as an operating fluid. Afterward, a combined 1D/3D simulation is carried out in order to simulate the real control strategy of the machine as well as to accurately determine the flow dynamic within the piping. Finally, the two approaches are confronted when using a non-Newtonian fluid and their advantages and limitations are outlined.

The economic assessment of an integrated anaerobic digestion and gasification system for the exploitation of the residues from an urban sewage treatment plant is carried out. The obtained bio-fuels are used in a cogeneration unit to produce both electric and thermal energy. The analysis focuses on the water treatment plant of a touristic town, characterized by a highly variable number of inhabitants. Therefore, the amount of input biomass for the integrated plant results remarkably time dependent and the design accounts for the transient nature of the input. The performance of the integrated system is modelled by developing an ad-hoc dynamic library for the simulation of the energy conversion systems under the OpenModelica open source platform. The system's performance and economic assessment are modelled by means of equations and correlations that calculate the components' behaviour on a time dependent basis. The simulation demonstrates that the final wastes to landfill decrease by a 73% improving significantly the environmental impact of the plant. Furthermore, the proposed integrated system is able to produce the 25% of the electric energy required for the plant operation. Thus, the payback period of the integrated plant results to be lower than 3 years.

The paper focuses on the CFD analysis of a full-scale module of an industrial ceramic kiln under actual operating conditions. The multi-dimensional analysis includes the real geometry of a ceramic kiln module employed in the preheating and firing sections and investigates the heat transfer between the tiles and the burners’ flame as well as the many components that comprise the module. Particular attention is devoted to the simulation of the convective flow field in the upper and lower chambers and to the effects of radiation on the different materials is addressed. The assessment of the radiation contribution to the tiles temperature is paramount to the improvement of the performance of the kiln in terms of energy efficiency and fuel consumption. The CFD analysis is combined to a lumped and distributed parameter model of the entire kiln in order to simulate the module behaviour at the boundaries under actual operating conditions. Finally, the CFD simulation is employed to address the effects of the module operating conditions on the tiles’ temperature distribution in order to improve the temperature uniformity as well as to enhance the energy efficiency of the system and thus to reduce the fuel consumption.

This paper investigates a new concept for the CO2 emission mitigation in the ceramic industry based on carbon reduction and methane formation. The concept is analysed as a retrofit to the natural gas fuelled ceramic kiln that represents the main responsible of this industry in terms of energy consumption and exhaust emissions. The carbon dioxide conversion to methane is obtained by reduction with hydrogen on a Ni catalyst and thus methane is used to fuel the standard burners that equip the kiln. The paper addresses different sources for the hydrogen used as a feedstock for the proposed concept as well as alternative catalysts are explored and compared in terms of reduction efficiency and costs. A lumped and distributed parameter simulation of the entire ceramic kiln is combined to the CFD simulation of the reactor to estimate the efficiency of the CO2 reduction and the corresponding methane production for a reference ceramic kiln. The results of the numerical simulations are then employed to discuss the potential benefits of the proposed concept in terms of carbon dioxide emission reduction for the ceramic production. An economic assessment of the system analysed is also carried out concept to determine the investment necessary to implement the technology in an existing ceramic kiln. The potential replicability for other industrial sector is also addressed.

This article explores a dual approach to real-time software development. Models are written in UML, as this is expected to be relatively easy and economic. Then models are automatically translated into a formal notation that supports the verification of properties such as safety, utility, liveness, etc. In this way, developers can exploit the advantages of formal notations while skipping the complex and expensive formal modelling phase. The proposed appraoch is applied to the Generalised Railroad Crossing (GRC) problem, one of the best known benchmarks porposed in the literature. A UML model of the GRC is built, and then translated into TRIO (a first order temporal logic). The resulting specification properties are tested by a history checking tool which exploits the formality of TRIO. The work described here highlights the shortcomings of UML as a real-time modelling language, proposes enhancements and workarounds to overcome UML limitations, and demonstrates the viability of using UML as a front-end for a formal real-time notation. By translating the GRC model into TRIO, we also give formal semantics to some of the UML constructs.