Dipartimento di Ingegneria Meccanica, Energetica e Gestionale - Tesi di Dottorato

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Questa collezione raccoglie le Tesi di Dottorato afferenti al Dipartimento di Ingegneria Meccanica, Energetica e Gestionale dell'Università della Calabria.

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End date: 2023

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    Fattibilità tecnica, sostenibilità ambientale ed economica di un piccolo impianto di digestione anaerobica installato in Calabria
    (Università della Calabria, 2021-11-09) Segreto, Marco; Critelli, Salvatore; Pinnarelli, Anna Ketty; Petracchini, Francesco
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    Modellazione Numerica per l’ottimizzazione multi-obiettivo di sistemi in assetto co- e tri-generativo
    (Università della Calabria, 2022-07-08) Lucarelli, Giuseppe; Conte, Enrico; Fragiacomo, Petronilla
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    Studio delle tecnologie di localizzazione acustica subacquea e sviluppo di tecniche per la riduzione dell'errore di posizione
    (Università della Calabria, 2023-02-08) Aiello, Rosario; Conte, Enrico; Bruno, Fabio
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    The Role of Physics Based Modeling of Macro/Micro Machining Operations in the Era of Electric Vehicles Revolution
    (Università della Calabria, 2021-05-28) Rinaldi, Sergio; Conte, Enrico; Umbrello, Domenico
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    Quantitative approaches for the integrated management of agri-food supply chains
    (Università della Calabria, 2021-06-10) Solina, Vittorio; Conte, Enrico; Mirabelli, Giovanni
    In recent years, the development of global markets and higher expectations from end customers have forced the supply chain players to better coordinate and integrate their plans, in order to maintain high levels of performance and be competitive on the market. Today, in fact, companies compete not only on product price or quality, but also on the reliability and timeliness of deliveries. Managing a supply chain in an integrated and coordinated manner is even more complicated and challenging, with reference to the agri-food context, where the constraints about quality and safety of goods, that are usually perishable, are much more stringent than in other sectors. By coordinating the various activities, it is possible to make supply chains more efficient and sustainable, as products can be made and distributed in the right quantity, at the right time and to the right customer. In support of integrated planning, new technologies are recently spreading, with the aim of making the sharing of data and information between the various actors safe and efficient. In this regard, the blockchain is among those technologies, whose interest has grown the most in recent months, both from the academic and business world. The present dissertation mainly aims to develop, test and validate novel quantitative approaches for the integrated management of agri-food chains. • In Chapter 2, a review of the main scientific works published in the last 15 years is proposed, referring to the integration of production, storage and distribution activities, via optimization strategies, within perishable supply chains. In this context, in order to identify effectively the different research gaps and to suggest possible future challenges, a five-dimension classification framework is proposed. This review is the starting point for the following 3 chapters, which address as many case studies. • In Chapter 3, an optimization model is designed for the simultaneous management of the storage and distribution of agricultural products. It is used to maximize the profits of a real company, which deals with the planting, growing, harvesting, storage and distribution of cauliflowers to a main customer and to spot customers. A hybrid fresh-/old-first inventory management policy is modeled to balance the quality of the delivered product and limit the amount wasted. The model improves the current practices of the firm and supports effectively the day-to-day decisionmaking regarding the quantities of product, for each age, to be stored and distributed to each customer. • In Chapter 4, a model is instead developed and tested to integrate the activities of production (i.e., harvesting), storage, distribution and routing of perishable agri-products. The case study refers to two companies, located in Southern Italy. At the tactical level, the proposed model determines the optimal value of two important operating parameters: the frequency of the harvesting activities and the service level to be guaranteed to customers. At the operational level, instead, the model is a valid tool to suggest to the company, day-to-day, the optimal quantities to harvest, store, distribute, and the routes to travel to reach customers, in order to maximize profits and contain waste. In this context, considering that the companies of the case study share some customers and are not in competition, as they are heterogeneous in terms of marketed products, the possibility of horizontal collaboration is also explored. The collaboration, as intended in this Chapter, implies that one of the two actors makes its own fleet of vehicles available, in exchange for a fee. In this context, a heuristic framework is proposed and validated. It suggests collaborating day by day, only if collaboration is economically convenient for both the companies. Computational tests, carried out on randomly generated instances, reveal that the collaboration can guarantee significant savings in terms of CO2 emissions and therefore make the supply chain more sustainable. • Chapter 5 deals with the integration of the production, storage and distribution activities of a company in the vegetable sector. In the production field, a scheduling problem is solved, which takes into account the set-up times of the production line, the hourly fluctuations in the energy price and the perishable nature of raw materials. In the distribution field, instead, it is necessary to schedule deliveries in terms of quantity of shipped products and days. The proposed model allows to schedule both production and distribution in an integrated way. Two rescheduling strategies are tested, to adequately react to customer demand, which occurs on a weekly basis. The first reproduces the current behavior of the company, while the second allows to improve current practices and jointly minimize the costs of energy, storage and distribution. • In Chapter 6, considering the recent proliferation of scientific works on the theoretical or practical use of blockchain technology in the agri-food sector, a literature review on this topic is proposed. This tool, since it allows the real-time sharing of information between the various players in the supply chain in a safe and efficient way, can facilitate the coordination of production and distribution plans, which is the main subject of the previous chapters of this thesis work. The aim is to identify current research trends and inform the reader about the degree
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    Towards the Clean Energy Building Community: multi-objective optimization of photovoltaic-wind-battery assisted heat pump systems in the presence of electric vehicle charging stations
    (Università della Calabria, 2021-06-10) Matera, Nicoletta; Conte, Enrico; Oliveti, Giuseppe; Mazzeo, Domenico
    La tesi di dottorato si propone di analizzare l'abbinamento di sistemi ibridi rinnovabili con sistemi di accumulo al fine di mitigare l’incertezza e l’intermittenza di tali risorse e, quindi, di raggiungere una maggiore affidabilità nel soddisfare il carico richiesto e ridurre l'energia in eccesso. La ricerca si è focalizzata sullo studio di una “Comunità a Energia Pulita” in cui sistemi ibridi tri-generativi composti da sistemi eolici, fotovoltaici, di accumulo e pompe di calore sono impiegati per la produzione di energia elettrica ed energia termica “calda” e “fredda” per la climatizzazione degli edifici, per fornire elettricità a distretti di edifici residenziali o di uffici e per alimentare stazioni di ricarica dei veicoli elettrici. Viene fornite una panoramica e un database matriciale aggiornabile dei 550 articoli scientifici più rilevanti nella letteratura scientifica pubblicati nel periodo 1995-2020, propone diversi strumenti di dimensionamento e previsione delle performance della comunità a servizio dei progettisti e dei legislatori. Sonpo state considerate, tenendo conto degli aspetti energetici, economici e ambientali: • diverse applicazioni; • varie configurazioni di impianto stand-alone e grid-connected (con e senza batterie di accumulo, con e senza sistemi eolici, con e senza sistemi fotovoltaici, con e senza pompe di calore e con e senza stazioni di ricarica di veicoli elettrici); • differenti condizioni di carico e località nel mondo. Le procedure proposte si basano su analisi dinamiche e sul confronto sistematico e l’ottimizzazione di opportuni indicatori di performance, per individuare le migliori condizioni climatiche nel mondo e profili di carico e per determinare l'affidabilità energetica del sistema, oltre che la massima convenienza economica e il massimo abbattimento di emissioni inquinanti. Infine, il consistente database creato è stato impiegato per creare un tool per il dimensionamento e per la previsione delle performance della comunità ad energia pulita impiegando tecniche di intelligenza artificiale basate sulle reti neurali artificiali. Il tool previsionale è applicabile ad una qualsiasi comunità ad energia pulita, con una qualsiasi potenza nominale installata, senza limitazioni geografiche, da implementare potenzialmente in qualsiasi località del mondo, e abbinabile a qualsiasi andamento di carico. Lo strumento, inoltre, con pochi dati annuali in input è in grado di determinare direttamente le prestazioni annuali della comunità senza eseguire alcuna simulazione dinamica ottenendo risultati molto accurati quanto quelli derivanti da simulazioni orarie.
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    Metodi e tool per l'ottimizzazione della calibrazione e della validazione dei sistemi di controllo motore
    (2012-09-29) Guzzo, Alessandra; Rizzuti, Sergio; Bova, Sergio; Riegel, Alessandro
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    Shape Memory Alloy connectors for Ultra High Vacuum applications: a breakthrough for accelerator technologies
    (2017-06-29) Niccoli, Fabrizio; Furgiuele, Franco; Cedric, Garion
    The design of tight connections for ultrahigh-vacuum (UHV) systems is a key subject for vacuum technology. Design requirements become even more stringent when dealing with UHV beam-pipe coupling in high-energy particle accelerators, where reliability and safety are core issues. For this specific application, additional needs often arise: strict geometrical and/or space limitations, connection of dissimilar materials and installation in restricted access areas. The latter constraint is of major concern, especially in the new generation of high-energy particle accelerators such as the HL-LHC (High Luminosity Large Hadron Collider), which will be operational at CERN (European Organization for Nuclear Research) in 2026. Owing to the increased proton-beam intensity and luminosity of the HL-LHC, radioactivity will be higher at some points than in the present LHC. The radiation exposure time of the technical personnel in some critical areas will be strictly controlled and minimized. The use of standard ConFlat® flanges (CF) or quick connect ConFlat® flanges (QCF) could result in significant design and operational/maintenance limitations. In particular, the mounting and dismounting of CFs are time-consuming due to the high number of bolts and lead to significant radiation doses incurred by operators. Conversely, QCFs can be installed more quickly, but they suffer from the requirement of more space and are unwieldy components comprising heavy stainless-steel chain clamps. Within this framework, Shape Memory Alloys (SMAs) offer a unique possibility to generate tight connections and fast clamping/unclamping by remotely changing the temperature of the SMA junction unit; at the microscopic scale this occurs trough a reversible solid-state transformation between the parent austenitic phase and the product martensitic one. In this PhD work, SMAs were used to develop a new generation of vacuum tightening systems for accelerator beam-pipe coupling by exploiting their shape recovery capabilities and actuation principles. The proposed coupling system consists of a SMA ring and a sealing element to be placed at the SMA-vacuum chambers interface, i.e. a copper coating or a thin cylindrical aluminum/copper gasket. Commercial NiTiNb rings and NiTi sleeves ad-hoc developed by Intrinsic Devices Inc. (USA) based on CERN technical constraints were properly investigated. The rings show two-way shape memory effect 􀍞remembering􀍟 a contracted austenitic shape and an enlarged martensitic one. The thermomechanical properties of the selected SMAs were measured experimentally. The tightening performance of SMA rings, was studied for different values of the initial clearance between the SMA ring and the vacuum pipe. The contact pressure was estimated by both strain gauge (SG) measurements and by Digital Image Correlation (DIC), using an ad-hoc developed numeric procedure. A novel design method was proposed that involves numerical results, obtained from Finite Element (FE) simulations and a literature vacuum sealing model. Leak tightness tests were carried out to assess the sealing performance of the of SMA-based prototype UHV chambers even after ageing at room temperature and repeated thermal cycles. Irradiation tests on SMA-based prototype vacuum chambers (SMA absorbed dose > 100 kGy) was performed at CHARM (Cern High energy AcceleRator Mixed field) facility at CERN and the functional and leak tightness performance of the couplings was successfully verified afterwards. The main results revealed that the contact pressure is not significantly affected by the initial SMA ring-pipe assembly clearance due to the plateau in the stress-strain response of the material. Thermal dismounting and subsequent re-clamping is obtained by exploiting the two-way shape memory recovery capabilities of the alloys. Leak rate measurements showed that the constraints for UHV applications could be easily satisfied (leak rate < 10-10 mbar l s-1) even after multiple thermal cycles; this opens the possibility of remotely clamping/unclamping the tight couplers by well-defined temperature variations. The proposed SMA-based beam-pipe couplers can be installed without using any connection flange. They are smaller and lighter than CF and QCF devices currently used in UHV systems at CERN. These bolt-free SMA-based connectors could provide significant benefits in terms of installation-dismounting time, space occupancy, bi-material joining and, above all, possible remote thermal activation, obtainable, for example, with removable heating/cooling collars. Based on these results, possible applications in CERN accelerators have already been identified. A first use has been proposed for the ISOLDE (Isotope Separator On Line DEvice). A second application is the vacuum system of the Large Hadron Collider (LHC) between the two high-luminosity experiments (ATLAS and CMS) and the beam focusing-defocusing quadrupole magnets (frequently called inner triplets). Moreover, particle collimators are also critical devices of accelerator equipment. In all these applications, high-energy particles induce a large radioactivity and, consequently, personnel access is restricted. The use of SMA rings with remote clampingunclamping features could be beneficial to avoid contamination and irradiation of technical personnel. Finally, SMA coupling installations are already planned in the CLEAR test facility at CERN, which provides the electron beam for the Compact Linear Collider (CLIC) study.
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    Occupants behavior influence on buildings energy performance. Investigations in residential and office buildings
    (2017-10-27) Mora Guerra, Dafni Yeniveth; Furgiuele, Franco; De Simone, Marilena
    The general objective of the research was to evaluate the main factors affecting the energy performance of buildings by considering both physical and occupancy variables. The research had two different approaches, one of them was regarding occupant behavior related to energy consumption in residential buildings and the other focused on the office buildings. The investigations were conducted by means of data collection and statistical analyses in existing residential buildings. Furthermore, different procedures for obtaining occupancy profiles were applied. Finally, a case of design and modeling of Nearly Zero Energy Buildings was developed in order to study the influence of occupancy in high efficient energy buildings. The results showed that different approaches of modeling occupancy can lead to considerable variations in building energy performance. In office buildings, the detection of occupancy was obtained by an experimental approach. First of all, the state of the art regarding the sensors and devices used for measuring and monitoring indoor parameters was defined. Successively, an experimental setup was created in an office of the University of Calabria in order to collect data on occupancy and energy consumption by means of sensors and manual observations. The criterion of sensor fusion was adopted. Data were processed by using different statistical techniques: clustering analysis, descriptive and stochastic elaborations. The results were models that can be used either to describe or predict occupancy profiles. Structure of this work The thesis is divided into six chapters. The first chapter is a general introduction titled Occupant behavior in buildings, regarding occupant behavior and its relationship to the energy consumption in residential buildings, office buildings, and low energy buildings. At the end of this chapter a brief description of occupant behavior and energy simulation in buildings is presented. In the second chapter, Building occupancy is presented with a description concerning the occupancy sensing techniques used and general classification following different approaches. Residential buildings is the title of the third chapter in which we attempt to describe the objectives and main findings of three investigations regarding residential buildings and occupancy profiles definition by means of the development of cases of study. The title of the fourth chapter is Office buildings: the experimental study. It consists of the description of the experimental study realized at the University of Calabria in an office building. A description of the sensors and the monitored data were presented. The Office buildings: data analysis is the fifth chapter of the thesis, with the different approaches used to analyze experimental data. It begins with the statistical analysis and ends with the results of the modeling based on indoor environment measurements. The General conclusions is the last chapter of the thesis, with a review and discussion of the key contributions of this research work
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    Modelli organizzativi e servizi ICT a supporto dello sviluppo sostenibile di sistemi agroalimentari e turistici locali
    (2018-05-04) Della Gala, Marco; Furgiuele, Franco; Volpentesta, Antonio Palmiro