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Laser-based three-dimensional velocimetry techniques have been recently undergone a fast and significant development enabled by the improvements in both hardware and processing methods. The benefits of this progress are huge especially in the field of the investigation of complex turbulent flows. In this paper, the application of time-resolved tomographic particle image velocimetry (TPIV) to the analysis of submerged impinging swirling jets is presented. Swirling flows recur both in natural phenomena and industrial processes and impinging swirling jets have been extensively investigated for heat transfer applications; however, three-dimensional and time-resolved investigations on the impinging flow fields of swirling jets are rare in the literature. The current study focuses mainly on the effects of the swirl number on the formation and development of the coherent vortex structures arising in this kind of flow. Five values of the swirl number, including the non-swirling case (S=0, 0.23, 0.43, 0.61 and 0.74) are investigated for fixed values of the Reynolds number (Re=5,100) and the impingement distance (equal to two nozzle exit diameters). TPIV measurements are carried out both in the near field (in proximity of the nozzle exit) and in the impingement zone (in proximity of the wall). In the latter case, the water jet is set to a temperature higher than the ambient one and the wall temperature distribution is measured via time-resolved infrared (IR) thermography with the aid of a transparent IR window. The simultaneous velocity and temperature measurements elucidate the role of the vortex structures in both the flow dynamics and transport of internal energy, which is a passive scalar in the present operating conditions. Modal decomposition techniques, in particular the proper orthogonal decomposition, are also applied to identify the most characteristic structures of the turbulent flows.

Sweeping jets are characterized by an oscillating motion and they are generated by a fluidic oscillator with no moving part [1]. The geometric characteristics of such an oscillator deeply affect the fluid dynamic behavior of the issued sweeping jet. In order to characterize the mean flow field, the oscillating coherent flow field and the turbulent statistics of impinging sweeping jets, phase-locked particle image velocimetry (PIV) measurements are carried out. Several sweeping jet devices have been studied. In particular, three different mixing chamber lengths (2.5w, 3.5w and 4.5w) have been investigated at Reynolds number equal to 6300 and nozzle-to-plate distance (H) ranging between 2 and 10 nozzle width (w). The flow field, for the case characterized by the longest mixing chamber (4.5w) and shortest nozzle-to-plate distance (2w), is reported in figure 1. These results show a double peak distribution of the time-averaged streamwise velocity component U, caused by the oscillation of the sweeping jet, in agreement with the literature, while the time-averaged vertical velocity component V exhibits the typical behavior of a wall jet. The time-averaged phase correlated kinetic energy (PKE) and turbulent kinetic energy (TKE) maps highlight the regions where the coherent and uncoherent fluctuations are stronger. The observed PKE behavior can be explained considering the oscillating nature of the sweeping jet, while the TKE distribution is mainly caused by the presence of the oscillating jet shear layer.

Rotating Rayleigh-Bénard convection (RBC) is the buoyancy-driven flow resulting from temperature gradients parallel to the gravity in the presence of rotation. In this work we comparatively present the results from an experimental and numerical investigation of RBC in a cylindrical cell with aspect ratio of 1/2 in non-rotating conditions and at different Rossby numbers. On the experimental side, time-resolved tomo-PTV is used to perform whole-field velocity measurements in a cell immersed in a water tank with constant controlled bulk temperature. This setup is accurately modeled in the direct numerical simulations by including the presence of the sidewall in the computational domain and solving the temperature field in both the fluid and solid regions. Excellent agreement between experiments and DNS is found for the non-rotating convection, whereas some discrepancies are observed when rotation is added. The latter might be related to the specific motions in the water tank at the outside of the experimental cell.

The present work addresses the development of a camera calibration model, based on the pinhole approximation and Snell’s law of refraction, for tomographic particle image velocimetry measurements inside transparent cylinders. Such a model adds to the pinhole-camera model parameters a relatively small number of parameters, which have an unambiguous geometrical or physical meaning. A calibration procedure for the innovative camera model is also outlined. Finally, the innovative model is comparatively assessed against the classical pinhole camera model and different polynomial-based models by using experimental data from an investigation of Rayleigh-Bénard convection.

This paper presents an experimental investigation of Rayleigh-Bénard convection in both rotating and non- rotating conditions. Rayleigh-Bénard convection, the fluid flow driven by temperature gradients parallel to the gravity, is relevant to a great variety of physical phenomena, ranging from motions in the atmosphere and the oceans to convection in the interior of planets and stars. In many of these applications, the interplay between a background rotation and the thermal convection has a key role in the fluid dynamic behaviour of the system. In the present work, the time-resolved tomographic particle image velocimetry (PIV) is used to investigate the whole domain of Rayleigh-Bénard convection inside a cylinder with aspect ratio equal to 1/2 at Rayleigh and Prandtl numbers equal to 1.86 ×10^8 and 7.6, respectively. The effects of rotation on the flow dynamics and evolution are also investigated in similar operating conditions at two different Rossby numbers, namely 0.25 and 0.1. The behaviour of the turbulent flow is analyzed both in the time-average and instantaneous evolution with focus on the large scale structures of the flow. Modal decomposition techniques are also used to identify the characteristic modes of the thermal convection.

This paper reports on the first large-scale three-dimensional investigation of thermal convection inside a cylinder by time-resolved tomographic particle image velocimetry. Rayleigh-Bénard convection is one of the most intensely studied problems in fluid mechanics due to its relevance to several fields of application, ranging from the geophysics and astrophysics to industrial engineering. Despite the huge amount of works on this subject, only few works have focused on three-dimensional experimental measurement of convection inside a cylindrical sample. In the present study, Rayleigh-Bénard convection is investigated in a cylinder with one-half aspect ratio at Rayleigh and Prandtl numbers equal to about 2E-8 and 6.5, respectively. The behavior of the turbulent flow is analyzed both in the time-average and instantaneous evolution. Focus is given to the structure and dynamics of the large–scale circulation. The azimuthal motion of the large-scale circulation is instantaneously traced and its relationship with the time-averaged flow field is investigated. Proper orthogonal decomposition is also used to identify the characteristic modes of the thermal convection. The most energetic modes are strictly related to the existence of the large-scale circulation, but interestingly the third and fourth modes exhibit a double-roll configuration, which is found to be the dominant pattern in the instantaneous flow field at some time instants.

In the present work, a very compact reaction system thermally integrated for the distributed hydrogen production by natural gas reforming is reported. The system is based on hydrocarbon Auto-Thermal Reforming, followed by a Water-Gas Shift module. A compact heat exchanger was placed between the two catalytic stages, in order to assure an appropriate thermal integration that avoid any other external heat duties. Experimental results demonstrated that the integrated configuration assured a good management of thermal fluxes in the system, in which an effective heat recovery from ATR exhaust gas to reactants was realized. Preliminary tests showed very impressive performances of the system, both by processing methane and natural gas. Despite a quite slow WGS stage, the processor was able to produce up to 10 Nm3/h of hydrogen, assuring a thermal efficiency higher than traditional systems.

With this research program, the optimized design of a discontinuous vertical press (descending pressure type) has been performed. It has a plate that moves downward causing the working pressure on the product, and having the capability to act with an average pressure on the varying product from 10 - 20 105 Pa. The considered machine has a traditional geometry and designed by modern computational codes, to reduce its cost without penalizing its performances. Further the structural validation has been performed and construction draws have been obtained. By mean this research program have been selected materials and accessories available on the market. The power is obtained by mean a connected piston hydraulic pump. The machine has PLC (electronic control system) able to check and to manage the times and ways of the working process. The machine is fully in conformity with to the legislations EU and CEE. Further this machine is still used, although nowadays pneumatic-presses and the rotating- presses are available on the market because it is able to furnish good qualitative results, beside to be simpler constructively and to use.

E’ stata effettuata la progettazione ottimizzata e la realizzazione di un distillatore per essenze vegetali di dimensioni estremamente ridotte, capace di gestire anche piccoli quantitativi. La caldaia ha il diametro pari a 500 mm e altezza pari a 650 mm. L’attrezzatura provvede all’estrazione delle sostanze volatili aromatiche presenti nella buccia della frutta o nelle vinacce funzionando sul principio della distillazione frazionata. Per l’ottimizzazione della geometria dell’attrezzatura considerata è stato usato un codice di calcolo per la modellazione solida, mentre la forma della caldaia e la disposizione dei gorgogliatori sono stati ottimizzati mediante un codice di calcolo termodinamico. Il distillatore è stato provato utilizzando bucce di limone parzialmente esaurite nel processo di produzione del liquore limoncello. I risultati estrattivi, le dimensioni compatte, i contenuti costi di realizzazione oltre che la versatilità ne fanno un ottimo strumento di laboratorio o da utilizzare per effettuare la verifica della fattibilità, della resa e della qualità di un processo industriale. Infine non si esclude un suo impiego per eventuali produzioni artigianali per prodotti di nicchia.

E’ stato realizzato un prototipo di gabbia per maricoltura off-shore di tipo sommergibile per sperimentare la possibilità di introduzioni in Italia dell’allevamento di Rombo chiodato (Psetta maxima) attraverso lo sviluppo di specifiche tipologie impiantistiche.Tale specie, largamente allevata sulle coste atlantiche di Francia e Spagna, necessita di cardinali termici alquanto bassi e non riscontrabili, almeno in superficie, nell’acque dell’area mediterranea. Tale ostacolo è stato superato con l’utilizzo di un prototipo di gabbia sommersa che, unitamente al sistema di ancoraggio, è progettata per variare la quota di localizzazione in profondità. Le difficoltà legate alla somministrazione di alimento in profondità sono state superate con l’utilizzo di un particolare distributore automatico risultato affidabile ed efficiente, in grado di trasportare l’alimento direttamente all’interno della camera di allevamento.Sono state condotte prove di accrescimento in profondità partendo da giovanili di circa 35 g immessi nel giugno 2004, che hanno raggiunto in circa 8 mesi una taglia media di 500 g. La risposta da parte dei soggetti allevati è da ritenersi positiva sia per quanto riguarda la velocità di accrescimento che la percentuale di mortalità. I risultati sin qui ottenuti soprattutto per quanto riguarda l’apetto impiantistico confermano la validità del metodo adottato e che in ambienti mediterranei lo spostamento in profondità è una soluzione valida per l’allevamento di Psetta maxima.

Anche nel settore della trasformazione industriale di prodotti alimentari la capacità di adeguamento per produrre nuove gamme di prodotti rappresenta certamente un punto di forza. I mercati, ormai dominati dalla grande distribuzione, fanno sempre maggiore richiesta di innovazione ed elaborazione della gamma dei prodotti da proporre al consumo, rendendo vulnerabili le industrie monoprodotto con linee verticali poco flessibili. Pertanto è stata sviluppata una ricerca per individuare un unico impianto capace di produrre diverse tipologie di prodotto. Durante la ricerca è stata effettuata l’analisi dettagliata di quattro ben distinte produzioni industriali: passata di pomodoro, salsa di pomodoro, succo di frutta e confettura di frutta, individuando la tipologia di macchine coinvolte. Mediante delle simulazioni numeriche sono state individuate le caratteristiche ottimali delle macchine considerate nonché sono stati individuati i layout ottimali. Successivamente è stata effettuata l’analisi dei “flow chart” dei singoli impianti considerati ed, infine, si è giunti alla definizione del layout di funzionamento del relativo impianto multiprodotto capace di effettuare la produzione considerata. L’impianto individuato consente di gestire 4 linee di macro prodotto riducendo anche i costi di ammortamento dei servizi di fabbrica intesi come generatori di vapore, centrale termica, cabina elettrica, immobili e impiantistica interna nonché tutti gli apparati di fine linea quali sistema di confezionamento e immagazzinamento.

È stata effettuata la progettazione ottimizzata di una lavatrice di bacche per ottenere una efficace pulizia del prodotto e ridurre al minimo il consumo di acqua. Nella parte più bassa del telaio della macchina è posto un nastro trasportatore in gomma con delle sopraelevazioni che favoriscono il trasporto dei sedimenti sul fondo della vasca. Inoltre per migliorare l’efficacia della fase di lavaggio del prodotto sono stati previsti dei getti d’aria in vasca opportunamente calcolati in modo da aumentare la turbolenza dell’acqua e migliorare così l’operazione.Al fine di conseguire una progettazione ottimizzata è stata effettuata una simulazione numerica del processo considerato. Successivamente sono state effettuate delle prove sperimentali per la validazione dei risultati ottenuti. Per effettuare l’ottimizzazione del processo considerato durante le prove di funzionamento è stato variato il rapporto Av definito come rapporto tra il volume d’aria iniettato per ora e il volume d’acqua presente in vasca. E’ stato rilevato che con quantità di bacche inferiori in volume al 25% della vasca, la quantità dell'aria iniettata è poco influente sul risultato finale, mentre con i rapporti dell'ordine del 25 % -30 % la separazione e la pulizia dei frutti cresce con l'aumentare della quantità d'aria iniettata (Av) fino a un valore di Av prossimo a 70. Per valori di Av compresi tra 70 e 110 i risultati restano immutati, mentre per valori di Av > 110 le particelle più sottili (terreno polverizzato) non sedimentano sufficientemente, quindi si ha un peggioramento delle condizioni operative.

The characteristics parameters of olive tree have been evaluated by inversion of vibrational data. This paper presents a combined numerical/experimental method which allows determination of the two transverse shear moduli in addition to the four in-plane moduli of a thick orthotropic plate of olive tree . E' stata adottata una tecnica non distruttiva basata su una sollecitazione ad impatto, procurata da un martello strumentato, e l'analisi della risposta dinamica del sistema. The olive tree plate response is natural frequencies of flexural vibration. The frequencies are measured by the impulse technique. In the numerical model for solution of the thick plate vibration problem, the Rayleigh-Ritz procedure is combined with a higher-order plate theory. Optimal parameter values are obtained by minimising the difference between theoretical model predictions and experimental data. This difference is formulated in terms of a Weighted least squares objective function. Approximate linearization schemes are used to asses the parameter uncertainty. An example is presented that shows the excellent agreement between measured and calculated frequencies that can be obtained. It is found that for moderately thick plates the reliability of the estimated values of the transverse shear moduli is good.

E’ stata effettuata la progettazione ottimizzata e la realizzazione di un pastorizzatore alla rinfusa per scatole in latta, con capacità produttiva pari a circa 600 scatole da 1 kg al minuto.Le scatole giunte alla fine del carrello trasportatore cadono per gravità in una vasca motorizzata, la cui struttura a sandwich è stata dimensionata mediante l’uso di codici di calcolo ad elementi finiti, e nella cui intercapedine è stata posta della lana roccia imbibita con acqua a 100°C per migliorare il processo termodinamico.Le scatole avanzano all’interno della vasca mediante una catena a tapparelle e sono portate lentamente all’interno di una seconda vasca nella cui intercapedine circola acqua a temperatura ambiente. In tal modo le scatole subiscono un rapido raffreddamento. Gli scambi termodinamici sono stati ottimizzati mediante delle simulazioni numeriche. Infine un sistema di riordino provvede ad orientare le scatole in posizione verticale e ad asciugarle con un soffio di aria calda.Il calcolo delle potenze termiche coinvolte durante il processo considerato ha consentito di determinare la potenza complessiva che è risultata essere pari a circa a 69,7 kW, comprese le perdite delle pareti. Ciò è stato calcolato tenuto conto che per il raggiungimento della temperatura di pastorizzazione sono necessari 5,23 kW e che questi sono necessari per la produzione di 10 scatole al secondo. Inoltre la fonte di energia utilizzata è stata il vapore surriscaldato la cui portata è stata determinata mediante simulazioni numeriche ed è risultata essere pari a 100 kg/h. Parole chiave: pastorizzatori , pastorizzazione, progettazione pastorizzatori

A research to compare the cultural results obtained with different kind of soil workmanship was performed. How crop of reference a summer – autumn grass meadow was select on which, as intercalary crop, literature recommends, immediately after the principal harvest, the execution of a good work of soil fissure, performed to the most greater possible depth. The tests was effected in an agricultural zone of the region Campania in Italy. The preparatory workmanships was all effected on dry soil and covered by stubbles of wheat, residual of the preceding crop, in a field on purpose divided in 8 blocks

In this research a methodology that allowed to optimize the working surface of a mouldboard plough was performed. The purpose was to obtain a working surface that during the soil workmanship requires the minimum values of draught force and of input energy costs. For this, it has been necessary to perform the study of the interaction soil-plough by a numerical simulation with the mathematical model of a plough mouldboard. To perform the validation of the used mathematical model, the plough mouldboard working surface was sensitized with pressure transducers to evaluate the pressure distribution during the soil workmanship and then the pressure distribution values evaluated on the working surface with the numerical simulations and those experimentally detected in full field were compared. This allowed to determine the mathematical model of the considered soil. Successively by geometry changes of the working surface considered and performing some numerical simulations, it was numerically determined a working surface that required the smaller values of energy expense and draught force. Such surface was realized and tested in full field noticing a 20% reduction of the draught force necessary, in comparison to a not optimized plough. Further it was noticed that the productive agronomic results were the same for both soil parts ploughed with optimized and not optimized plough

The research has been developed to verifying the operatore work quality of thè milk-cheese transformation sector in region Campania especially in worth to their exposure to the noise. For this investigators different productive realities in the province of Caserta are been analyzed focusing the attention on a dairy that has appeared for dimensions, workmanship organization , working turns like the most representative of the considered champion. It transforms for the almost totality of its billing, buffalo cow milk in mozzarella countersigned by mark DOP. The phonometric investigations has been conducted with the aid of an integrating phonometer of class I. The results underline that the levels of exposure to the noise measured often go beyond the level is accustomed to of 85 dB(A).

The application of Laser strain gauge technique for testing the mechanical properties of olive twigs is described. This method makes possible measurements at very low stress levels, thus preventing the exceeding of the low and inaccurately known elastic limit of the olive twig and olive shanks.

Water flowing through a netting panel imposes a load. which is transmitted supporting frame, collar and mooring system. The load on nets. used in aquaculture: has been shown to be dependent upon the nature of the material used the hapc arj the mesh, current velocity. Th e water density. Another element very significant for it is the formation of tabuling incrustation. Instrumentation was developed to measure the hydrodynamic thrust on netting and assembled on a circular tank for tests. The system comprises an engine. a with strain-gauge dynamometer that moves then panel with a variable speed from 0.1 m/s. and a data logger. The purpose of this study want to determine the hydrodynamic thrust for nets of e used size in off-shore mariculture and put in evidence the thrust difference fouling

An economic compact equipment and easily to use by the operators has been realized. It allows to check the direction of a tractor with an error of the order of the decimeters. It is formed by a rudder with two pressure sensors connected to the hydraulic power steering of a tractor. Such system can be also installed as “retrofit” on different types of tractors and it can be used or in way "stand alone" or in combination with other systems of autonomous guide

In this paper we describe the application of GPR and resistivity (dipole-dipole) methods to an archeological investigation. The aim of this study was to obtain information about buried pre-Roman structures below the Roman residence "Casa dell'Atrio a Mosaico", in the ancient town of Ercolano (Naples). A number of resistivity (dipole-dipole) and GPR profiles were carried out on the mosaic floor of the house. To perform resistivity profiles in a nondestructive way on the mosaic floor, special flatbase copper electrodes were used. The electrode spacing used was 1 m and 0.5 m. GPR data were collected using 100 MHz and 500 MHz antennas. The radar profiles were carried out primarily along the electrical profiles in order to obtain a direct comparison between the two methods. Both resistivity and GPR methods evidenced a number of structures buried at shallow depths. Both methods located a structure identified as a conductive body with electric parameters strongly contrasting those of the surrounding material. The archaeological interpretation of such structures is in terms of remnants of walls of pre-Roman houses and of a cistern used for collecting rain, connected to a pipe

The present work reports on the extended distribution of nineteen species in the Mediterranean. These are: Upeneus pori (Fish:Turkey), Bursatella leachii (Mollusca, Opisthobranchia: eastern coast of Spain), Sparisoma cretense (Fish: Ionian coast of Greece), Pseudobryopsis myura (Chlorophyta:Turkey), Aplysia dactylomela (Mollusca, Opisthobranchia: Karpathos island, and Kyklades Archipelago, Greece), Asparagopsis armata and Botryocladia madagascariensis (Rhodophyta: South Peloponnesos, Greece), Oxynotus centrina (Fish: Greece), Caulerpa racemosa var. cylindracea (Chlorophyta), Stypopodium schimperi (Phaeophyta) Siganus luridus and Stephanolepis diaspros (Fish) Percnon gibbesi (Decapoda, Brachyura) (Kyklades Archipelago, Greece), Cerithium scabridum (Mollusca, Prosobranchia: Anavissos: Greece) and Cerithium renovatum (Mollusca, Prosobranchia: N. Kriti), Cassiopea andromeda (Scyphomedusa: Rhodos Island, Greece), Abra tenuis (Mollusca Bivalvia: Vouliagmeni Lake, Greece) Lagocephalus lagocephalus (Fish: Calabrian coast, Italy) and Plocamopherus ocellatus (Mollusca, Opisthobranchia: Iskenderun Bay, Turkey).