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No full textI "Sassi" di Matera e i "Trulli" di Alberobello: valutazione delle prestazioni energetiche di edifici vernacolari della tradizione mediterranea attraverso simulazione dinamica e misure sperimentali
Energy and microclimatic performance of Mediterranean vernacular buildings: The Sassi district of Matera and the Trulli district of Alberobello
No full textExperimental research carried out on two types of buildings that are examples of vernacular architecture in Southern Italy, namely the Sassi of Matera and the Trulli of Alberobello are outlined in this pape
Modelling Analysis for Energy Production Using Wood Biomass
No full textThe energy production from biomass is the technology that receives the greatest wariness from outsiders. Combustion and emission of air pollutants, the identification of an any biomass plant with a w aste energy power plant, often interfere with thediffusion of these technologies of energetic conversion at local level. This paper gives rise to describe the characteristics of the operation of a plant for the exploitation of the wood biomass from a short productive chain. The aim is to propose a possible and advantageous solution from a technical and economie point of view but, above all, ecologica!, with the purpose to create a useful tool to relate with the stakeholders tliat operate in thè agricultural and industriai sector. The use of the ORC (Organic Rankine Cycle)energy technology is a solution by now tested and particularly suited for working joint to small size thermal plant operating at low temperature.
In this paper, the obtainable energy performances by means of such energy plant joint to boilers fed with wood biomass will be analyzed showing the results of an energy and exergetic modelling of the ORC units. The proposed solution consists in the integration of the firewood boilers with a circuit of diathermic oil able to feed the ORC plant.
In this way, we produce power and heat, to be used also for district heating applications, to reach a more complete energy exploitation of the biomass. The simulation model of this energy system has allowed to get with good approximation the obtainable performances. varying some free parameters of design and eontrol, shaping itself as an essential tool in the evaluation of the actual energy saving and of the concrete technical-economic feasibility
Energy analysis of hybrid solar collectors integrated in architecture
No full textIn recent years, the architectural integration of PV modules on buildings has become increasingly widespread, especially in parts of the world most industrialized, where government incentives have accelerated its diffusion. The installation of photovoltaic systems architecturally integrated into building structures certainly has advantages, if compared with systems installed in facilities separate from the building. The performance can be improved if
the heat produced by the module is removed. So far, in architecturally integrated plants, the heat removed from the photovoltaic cells was always dissipated into environment. Instead in this work we tried to understand if it is possible to use, in addition to electricity, also the heat inside the buildings by means of solar hybrid collectors. Then the energy rejected from the
photovoltaic conversion could be used to integrate the energy required to satisfy the building demand.
The level of the techniques used by hybrids collectors on the market still needs to be tested, verified and monitored. We still need to determine combinations of materials, the influence of
input and output temperature from the collector, the global efficiency and the excellent combination of heat and electricity.
The purpose of this study is the analysis of solar hybrid systems architectonically integrated with the objective of maintaining high electrical performance of photovoltaic conversion, considering the amount of total energy obtained in the comparison between the water and air collectors
Analisi anemologica e stima del potenziale energetico di turbine minieoliche per il sito del Parco della Murgia Materana
No full textL’uomo nel corso di millenni ha sempre sfruttato l’energia eolica, sia come mezzo di propulsione (navigazione) sia come lavoro meccanico (mulini e pompe); questo sfruttamento è avvenuto con bassa tecnologia e solo a partire dal ‘700 è iniziato prima un processo di miglioramento delle macchine e, nel ‘900, l’avvento della conversione elettrica. Attraverso lo studio della risorsa eolica fatta nel sito della Parco della Murgia Materana, situato nell’altopiano murgiano tra la Basilica e la Puglia, è stato possibile ricavare il potenziale eolico di questa area del sud Italia. Le misurazioni, svolte per un periodo di 365 giorni hanno permesso di caratterizzare la ventosità del sito e valutare da un punto di vista energetico, economico e ambientale quattro tipologie differenti di aerogeneratori mini-eolici, due ad asse orizzontale di potenza 6 kW e 20kW e due ad asse verticale di uguale potenza. Questa tecnologia, caratterizzata da un basso impatto ambientale, può essere utilizzata per alimentare utenze, anche in aree soggette e vincolo ambientale, con bassissimi costi di installazione e manutenzione. L’analisi sulla producibilità energetica, sulle ore equivalenti, sul ritorno economico dell’investimento e sui benefici ambientali in termini di emissioni di CO2, NOx, SOx e TEP rispetto alla stessa energia prodotta da fonti convenzionali (centrale termoelettrica) hanno permesso di determinare quale tra le turbine è quella che meglio si adatta al sito studiato.
L’ultima analisi è stata quella di valutare il costo del kWh prodotto e confrontarlo con le altre fonti energetiche; il valore ottenuto è risultato competitivo eguagliando il valore costo del kWh prodotto da una centrale termoelettrica o da una centrale nucleare di terza generazione con notevoli vantaggi ambientali, quali l’assenza di emissioni di CO2 e di stoccaggio di scorie nucleari
Energy and microclimatic performance of restored hypogeous buildings in south Italy: The "Sassi" district of Matera.
No full textThe site of the “Sassi of Matera” classified by the United Nations Educational, Scientific and Cultural Organization (UNESCO) as World Heritage in 1993, is an exceptional example of traditional bioclimatic Mediterranean architecture. Within this immense artistic heritage, we find hypogea habitations, stone buildings, and mixed habitation – half-hypogeum and half-built. In this study, we analyze the energy and microclimatic performance of hypogeous structures in three states: not-restored, immediately after restoration, and a few years after restoration (in normal use). We monitored a surface hypogeum and a deep hypogeum. We performed a dynamic parametric simulation using the software EnergyPlus to quantify the energetic balance of the hypogeous structures during one calendar year. The energetic valuation of the surface hypogea shows that these environments, once restored and in a condition of normal use, give indoor comfort within the limits of comfort thermo-hygrometrics established by the comfort indices of predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD). The huge thermal mass of the walls ensures that the microclimate indoor conditions are regular throughout the seasons, without differences in the daily thermal oscillation. Deep hypogea without an air change system cannot reach thermal-hygrometric comfort values. We determined that these structures have a null thermal balance during mid-season, while in the summer the floor loses heat, thereby cooling the environment. The opposite occurs in winter. We can conclude that these buildings were designed as bioclimatic. In fact they can be used, after restoration, with limited use of technology systems
On the use of FEM and FDTD numerical methods to predict acoustic behaviour of small rooms
No full textAddressing heterogeneity sources in manufacturing sustainability assessment using the system design view
No full textAssessing manufacturing sustainability has become a task of paramount importance to date for the decisional impact over the whole product or process life cycle. The consistency of the sustainability assessment results derives from several practitioner's choices and assumptions, depending on materials, the technological processes as well as the geographical context, that may be sources of heterogeneity. Addressing the sources of heterogeneity in sustainability assessment deriving from data contexts, procedural decision-making methods, measurement procedures is critical, provided that all existing methodologies, such as Life Cycle Assessment, Exergy Analysis and methods derived from their combinations, leave an important role to the subjective judgment of the practitioner. Heterogeneity is thus related to the possible different perspectives in drawing decisions, which may, for instance, reflect into the selection of dissimilar inventorying for the impact evaluation as well as in the selection of the most suitable impact category: the effect is the uncertainty in the final results. Heterogeneity issue can be attributed to multiple dimensions, such as data sources, indicators and subjective perspectives. In this paper, the problem of facing the sources of heterogeneity in sustainability assessment is discussed by endeavoring the system design view as a kind of guideline to implement the Exergy-based Analysis within the Life Cycle Thinking. The Life Cycle Assessment and Exergetic Analysis approach is carried out not to improve the methods themselves, but to revisit the entire design process, to improve it, with the aim of driving the decision of the practitioner, to make the results of the assessment more comparable, regardless of their subjective choices. An industrial case study is taken as a reference to prove the approach proposed and to highlight gaps that have not yet been filled. (C) 2022 CIRP
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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