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The performance of various designs of outdoor noise barrier has been investigated using numerical modelling and full scale experiments. The numerical modelling has been performed using a two-dimensional boundary element method. The model has been extended to allow the efficient simulation of barrier arrangements on ground having two distinct impedance values and cross-sections incorporating cuttings. It has been reported previously that the performance of a plane screen can be enhanced by adding a device to the top of the barrier to induce destructive interference. Full scale modelling and boundary element simulations have been performed on one such commercially available device. It has been shown that, taking the height increase into account, the major contribution to the improved performance is the presence of two diffracting edges rather than any interference effects generated. It is known that the performance of a single barrier is degraded following the introduction of a barrier on the opposite side of a source. Boundary element simulations of such parallel arrangements have been performed. Modifications have been proposed to reduce the over-estimation of multiple reflections within the model, together with a method for converting predictions to the equivalent point source values. Sound absorptive, tilted and median barriers have been shown to be effective in reducing the degradation. A multiple-edge barrier configuration is known to offer improved screening performance over a plane screen. Reported in-situ measurements have suggested the behaviour to be influenced by site geometry. Boundary element calculations have been performed to identify a more efficient variant of the device. The results suggest the addition of an inclined base panel to be most effective. The boundary element model has been used to investigate the effect of shape and surface treatment upon railway noise barriers. The model has been adapted to allow the use of dipole sources characteristic of railway noise. The cross-section of the rolling stock has been shown to affect the performance of rigid barriers. If the upper edges are coincident, the results suggest that simple absorptive barriers provide better screening than tilted designs. The addition of multiple edges further enhances performance.

Three dimensional laminar natural convection flow of and heat transfer in incompressible air between two inclined parallel plates are analyzed with the Boussinesq approximation by using spectral methods. The plates are assumed to be infinitely long in streamwise and spanwise directions. For these directions, periodic boundary conditions are used and for the normal direction constant wall temperature and no slip boundary conditions are used. Unsteady Navier-Stokes and energy equations are solved using a pseudospectral C code in order to obtain velocity and temperature profiles inside the channel. Fourier series are used to expand the variables in x and z directions, while Chebyshev polynomials are used to expand the variables in y direction. By using the temperature distribution between the plates, local and average Nusselt numbers (Nu) are calculated. Nu values are correlated with &amp / #966 / ,which is the inclination angle, and with Racos&amp / #966 / to compare the results with the literature. Additionally, non-dimensional velocity values and streamlines of the fluid are presented with proper plots.

Cette thèse s’inscrit dans le projet ASCoPE qui vise à développer les connaissances scientifiques et technologiques nécessaires à la conception et à la réalisation d’un pilote de production d’acier par réduction électrochimique de particules d’hématite en suspension dans un milieu alcalin à 110°C, en vue de proposer un procédé industriel fiable et écologique, comme alternative au procédé classique reposant sur le charbon. Le mélange considéré contient une suspension d’hématite à 12% en volume dans une solution aqueuse de soude à 50% en masse. Cette thèse a pour objectif l’étude de la sédimentation et de la rhéologie des suspensions d’hématite et le comportement hydrodynamique des particules d’hématite dans une cellule inclinée et de quantifier l’éventuel phénomène d’impact sur la cathode / This thesis aims to develop scientific and technological knowledge needed to design a pilot production of steel by electrochemical reduction of hematite particles suspended in an alkaline medium at 110°C in order to provide a reliable and environmentally friendly industrial process, as an alternative to the conventional process based on coal. The mixture considered contains a suspension of hematite of 12% by volume in an aqueous sodium hydroxide solution of 50% by weight. This thesis seeks to study the sedimentation and rheology of hematite suspensions and the hydrodynamic behavior of hematite particles in inclined cell and to quantify the possible phenomeno impact on the cathode

Submitted by Rodrigo Garcia Brunini null (rgbrunini@gmail.com) on 2016-02-26T17:17:57Z No. of bitstreams: 1 Dissertação_Rodrigo_Garcia_Brunini_2016.pdf: 1968086 bytes, checksum: 3bf99718970a4fb4c41a3c6f92e68f89 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-02-26T20:14:20Z (GMT) No. of bitstreams: 1 brunini_rg_me_jabo.pdf: 1968086 bytes, checksum: 3bf99718970a4fb4c41a3c6f92e68f89 (MD5) / Made available in DSpace on 2016-02-26T20:14:20Z (GMT). No. of bitstreams: 1 brunini_rg_me_jabo.pdf: 1968086 bytes, checksum: 3bf99718970a4fb4c41a3c6f92e68f89 (MD5) Previous issue date: 2016-02-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A cana-de-açúcar é uma cultura de fundamental importância para o país. Grande parte dos índices de seca ou estiagem agrícola consideram, ou somente a chuva, ou em alguns casos a interação entra água disponível no solo, como passivas, na evapotranspiração real e a potencial. Com este trabalho o objetivo foi de determinar o índice de estresse hídrico diário baseado na termometria a infravermelho, para a cana-de-açúcar em superfícies irrigadas. Foram avaliados dados meteorológicos do ambiente, o índice de estresse hídrico da planta com o uso do termômetro de infravermelho, o potencial de água no solo e analisada a condução do sistema produtivo durante o período de coleta de dados. A pesquisa foi desenvolvida na área experimental do Departamento de Engenharia Rural da FCAV/UNESP, em uma estrutura denominada “Bacia Hidrográfica Experimental”, utilizando superfícies caracterizadas como HNI (superfície horizontal sem irrigação), HI (superfície horizontal irrigada), 20N (superfície com 20% de declividade, exposição norte e irrigada), 40N (superfície com 40% de declividade, exposição norte e irrigada), 20S (superfície com 20% de declividade, exposição sul e irrigada), e 40S (superfície com 40% de declividade, exposição sul e irrigada). Os resultados deste estudo indicaram que: o índice de estresse hídrico diário acima de 5°C compromete negativamente a produtividade da cultura; a superfície de exposição sul com 20% de declividade apresentou maior produtividade sobre as demais superfícies estudadas; e a exposição e declividade do terreno influenciaram no manejo da irrigação e na produtividade para cada superfície estudada. / The sugarcane is a crop of vital importance to the country. Much of the drought indices or agricultural drought consider, or only the rain, or in some cases the interaction enters water available in the soil, as passive, the actual evapotranspiration and potential. With this work, the objective was to enter the daily water stress index based on the infrared thermometry, for sugarcane in irrigated areas. They evaluated environmental meteorological data, the water stress index of the plant with the use of infrared thermometer, the water potential in the soil and analyzed driving the production system during the data collection period. The research was conducted in the experimental area of the Department of Rural Engineering FCAV / UNESP, in a structure called "Basin Experimental", using surfaces characterized as HNI (horizontal surface without irrigation), HI (irrigated horizontal surface), 20N (surface 20% slope, north and irrigated exposure), 40N (surface with 40% slope, north and irrigated exposure), 20S (surface with 20% slope, south and irrigated exposure) and 40S (surface with 40% slope , south and irrigated exposure). The results of this study indicated that: the daily water stress index above 5°C adversely compromises the productivity of culture; south exhibition area with 20% slope had higher productivity on the other surfaces studied and exposure; and slope of the terrain influence the management of irrigation and productivity for each study area.

Submitted by DANIEL MARTIN GASLAC GALLARDO (dmgg7900@hotmail.com) on 2016-12-13T16:40:12Z No. of bitstreams: 1 gaslac.pdf: 23986592 bytes, checksum: 41ffd339aeeb8444e4703d37a1753df4 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-12-20T13:16:25Z (GMT) No. of bitstreams: 1 gallhardo_dmg_me_guara.pdf: 23986592 bytes, checksum: 41ffd339aeeb8444e4703d37a1753df4 (MD5) / Made available in DSpace on 2016-12-20T13:16:25Z (GMT). No. of bitstreams: 1 gallhardo_dmg_me_guara.pdf: 23986592 bytes, checksum: 41ffd339aeeb8444e4703d37a1753df4 (MD5) Previous issue date: 2016-10-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os novos dados obtidos do sistema de Plut˜ao, durante sua passagem pelo sistema em julho de 2015, est˜ao sendo enviados pela sonda New Horizons. Plut˜ao possui um conjunto de cinco sat´elites, Caronte (forma um sistema bin´ario com Plut˜ao), Estige, Nix, C´erberos e Hidra. A recente descoberta desses dois pequenos sat´elites, Estige e C´erberos, faz com que seja necess´ario reestudar essa regi˜ao externa, al´em da ´orbita de Caronte. Neste trabalho analisaremos a estabilidade da regi˜ao externa do sistema Plut˜ao-Caronte para um conjunto de part´ıculas-teste da ordem de cent´ımetros e micrometros sob a influˆencia gravitacional de todos os corpos do sistema de Plut˜ao e da press˜ao de radia¸c˜ao solar (para part´ıculas de micrometros). Essas part´ıculas estar˜ao inicialmente em ´orbitas excˆentricas e inclinadas; ser˜ao assumidos diferentes valores de excentricidade e inclina¸c˜ao. Resultados mostraram que para um conjunto de part´ıculas, originalmente localizadas no plano orbital do sistema de Plut˜ao, 10% colidiram com os corpos maiores e 25% foram ejetadas. J´a para o sistema de part´ıculas com ´orbitas inclinadas (I = 96.2 ◦ ), a maioria dessas part´ıculas s˜ao est´aveis. Apresentaremos os resultados obtidos para outros valores de inclina¸c˜ao e faremos a compara¸c˜ao com os resultados obtidos para um conjunto de part´ıculas microm´etricas da ordem de 1, 5 e 10µm. / The new data from the Pluto system during its passage through the system in July 2015, are being sent by the spacecraft NewHorizons. Pluto has a set of five satellites, Charon (forms a binary system with Pluto), Styx, Nix, Kerberos, Hydra. The recent discovery of these two small satellites, Styx and Kerberos, makes it necessary to restudy this outer region beyond the orbit of Charon. In this work we analyze the stability of the outer region Pluto-Charon system for a set of particle-test centimeters order and micron under gravitational influence of all bodies Pluto system and solar radiation pressure (for particle microns). These particles are initially eccentric and inclined orbits; They are assumed different eccentricity values and inclination. Results showed that for a set of particles originally located in orbital plane of Pluto system collided with 10% larger bodies and 25% were ejected. As for the particle system with inclined orbits (I = 96.2◦ ), most of these particles are stable. We present the results obtained for other of inclination values and make a comparison with the results obtained for a set of micrometric particles of the order of 1, 5 and 10µm.

Buoyant flows are present in nature and also in many engineering applications,from domestic heating to the cooling of nuclear power plants. This experimental study focuses on the effects of angle of inclination on buoyancy-driven flows inside tall, rectangular, differentially-heated cavities. The objective is to produce detailed local flow and thermal data, which will advance our understanding of the flow physics and also provide CFD validation data. It considers a 2.18m × 0.52m × 0.0762m cavity, resulting in an aspect ratio of 28.6, with its two opposing long walls maintained at constant but different temperatures, while all the remaining walls are thermally insulated. The Rayleigh number, based on the temperature difference and spacing of the long sides, is 0.86 x 106 for most cases and the working fluid is air (Prandtl number0.71). Experimental data for the flow and the thermal fields, using laser Doppler anemometry and Chromel-Alumel thermocouple traverses respectively, are presented for the cavity inclined at 60° and 15° to the horizontal, for both stable (the hot surface being the upper surface) and unstable (the hot surface the lower one) orientations. The 15° stable case is investigated at a higher Rayleigh number of 1.54 x106 and some additional data for the 15° unstable case are also presented at this high value of Rayleigh number. Comparisons with the measurements of Betts and Bokhari [1], for the same cavity at the vertical position, are also included. For moderate angles of inclination, the flow is two-dimensional and the effects of inclination are primarily confined to the fluctuating fields. For large angles of inclination, the flow becomes three-dimensional. In the unstable 15° angle of inclination case, a set of four longitudinal vortices are formed over the entire length of the cavity, with four counter-rotating re-circulation cells within the cross-section parallel to the thermally active walls. The enhanced mixing at 15° unstable inclination leads to uniform temperature in the cavity core and thus only minor deviations from two dimensionality in the thermal field. A modest rise in Rayleigh number, in the 15° unstable case, does not affect the mean motion, but causes an increase in the normalised turbulence intensities, which in turn leads to a more uniform temperature within the cavity core and a practically two-dimensional thermal field. The stable 15° angle of inclination case, surprisingly, leads to the formation of two longitudinal vortices and two re-circulation cells. The lack of mixing, in the 15° stable case, leads to more noticeable three-dimensional thermal field. The thesis includes a full set of flow and thermal predictions and also spectral analysis of thermal fluctuations, which show a significant effect of the angle of inclination on both the power density level and the ranges of frequencies involved.

Liquid wastes discharged from industrial outfalls have been researched for many years in the past. Majority of past studies, initiated in 1960s, were experimental studies mainly focused on basics of discharges such as key geometrical properties. Eventually, more robust experimental studies were performed to measure the mixing properties of effluent discharges with various jet configurations and ambient water conditions. Discharges could be as a means of submerged diffusers or surface channels and receiving water could vary from a homogenous calm ambient to a very complex stratified turbulent cross flow ambient. Depending on the bathymetric and economic situation around an outfall project, submerged discharges are preferred designs for most of ocean outfalls. It is the reason that majority of past studies have evaluated the mixing characteristics of submerged jets. Since early 1990s, the numerical modelling has emerged to support complex fluid mechanic problems. Later in 1990s and early in 2000s, the use of computational fluid dynamic (CFD) tools emerged in predicting the jet properties for the effluent discharges. Since then different numerical models have been developed for different applications. Similar to experimental studies, most of numerical studies have been focused on the submerged dense jet discharges. The current study intends to stay focused on the numerical modelling of such jets too; however, to cover the gaps in the literature. To achieve this, a thorough literature review was performed on the past CFD studies of over past 20 years to better understand what was done and what the gaps are. The results of this thorough review revealed that although there has been a great progress in the CFD studies in the field of effluent discharges, there are some applications that have not been investigated before, yet. It was found that there are some discharge inclinations that were not studied numerically before. Four discharge angles of 60°,75°, 80° and 85° were selected in this study, as previous studies mostly focused on 30° and 45°. The higher inclinations are more suitable for deep water outfalls where terminal rise height of the jet does not attach to the ambient water surface. The numerical model OpenFOAM was used in this study which is based on the Finite Volume Method (FVM) applying LRR turbulence model closure. LRR turbulence models was proved to be a capable choice for effluent discharge modelling. The second gap identified in the comprehensive literature review completed was the submerged dense effluent discharge into shallow water with surface attachment (for both inclined and vertical discharges). There was no previous numerical study of such jets identified. Three different regimes were identified: full submergence, plume contact and centerline impingement regimes (i.e. FSR, PCR and CIR). Key geometrical and dilution properties of these jets at surface contact (Xs, Ss) and return point (Xr, Sr) were extracted numerically and compared to those available from experiments. Two discharge angles (30° and 45°) were investigated based on the available experimental data. Five Reynolds-averaged Navier-Stokes (RANS) turbulence models were examined in this study: realizable k-ε and k-ω SST models (known as two-equation turbulence models), v2f (four equations to model anisotropic behavior) and LRR and SSG turbulence models (known as Reynolds stress models - six equations to model anisotropic behavior). Vertical dense effluent discharges are popular in the design of outfall systems. Vertical jets provide the opportunity to be efficient for a range of ambient currents, where the jet will be pushed away not to fall on itself. This research work investigates worst case scenario in terms of mixing and dilution of such jets: vertical dense effluent discharges with no ambient current and in shallow water where jet impacts the surface. This scenario provides a conservative design criteria for such outfall systems. The numerical modelling of such jets has not been studied before and this research work provides novel, though preliminary, insights in simulations of vertical dense effluent discharges in shallow waters. Turbulent vertical discharges with Froude numbers ranging from 9 to 24 were simulated using a Reynolds stress model (RSM), based on the results from inclined dense discharges to characterize the geometrical (i.e., maximum discharge rise Zm and lateral spread Rsp) and dilution μmin properties of such jets. Three flow regimes were reproduced numerically, based on the experimental data: deep, intermediate and impinging flow regimes.

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