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Large-eddy simulations (LESs) are performed for two isolated unheated jet flows corresponding to a Doak Laboratory experiment performed at the University of Southampton. The jet speeds studied correspond to acoustic Mach numbers of 0.6 and 0.8 as well as Reynolds numbers based on the nozzle exit diameter of about one million. The LES method is based on the compact accurately boundary-adjusting high-resolution technique (CABARET) and is implemented on graphics processing units (GPUs) to obtain 1000–1100 convective time units for statistical averaging with reasonable run times. In comparison with the previous jet LES calculations with the GPU CABARET method, the mean-flow velocity and turbulent intensity profiles are matched with the hot-wire measurements just downstream of the nozzle exit. The far-field noise spectra of the Doak jets are evaluated using two methods: the Ffowcs Williams–Hawkings approach and a reduced-order implementation of the Goldstein generalized acoustic analogy. The flow and noise results are compared with hot-wire and acoustic microphone measurements of the Doak Laboratory and critically analyzed in comparison with the NASA small hot jet acoustic rig database.

Jet-surface interaction represents a significant community noise problem for the installation of modern ultra-high bypass ratio turbofan engines. The use of chevron nozzles is known to reduce low-frequency jet mixing noise by increasing the mixing rate close to the nozzle. It is currently unknown, however, to what extent such a nozzle lip treatment affects the Kelvin-Helmholtz instability, generated in the vicinity of the wing, which will modify the source of jet-surface interaction noise. To clarify the physics of the jet-surface interaction noise source, an extensive experimental investigation was conducted using the Flight Jet Rig in the anechoic chamber of the Doak Laboratory, at the University of Southampton. Various measurements were carried out on a round and a chevron single stream, unheated subsonic jet, both in an isolated configuration and installed beneath a 2D NACA4415 airfoil "wing". The wall-pressure field on the wing surface was investigated using a pair of miniature wall-pressure transducers and a set of ultra-thin precision microphones. These sensors were flush-mounted in both the stream-wise and span-wise directions on the pressure side of the wing and the unsteady wall-pressure data were analysed in the time and frequency domains. The far-field noise results show significant broadband noise reduction by the chevron jet. This is further evidenced by a reduction in the span-wise correlation length along the wing trailing edge over a wide range of frequencies. Significant reduction of the tonal trapped wave energy is also observed.

International audience; An investigation into the installation noise from a semi-finite flat plate next to a jet was performed. The experiment was carried out in the ISVR's anechoic Doak Laboratory, at the University of Southampton, using wall pressure transducers flush mounted over the plate surface and a far-field microphone array. In order to reproduce a setup representative of a real scaled jet-wing configuration the plate trailing edge was located at three nozzle exit diameters axially downstream of the jet exhaust. The radial position of the plate was varied from 0.76 to 1.50, nozzle exit diameters from the jet axis to the plate surface. The jet Mach number was also varied from 0.3 up to 0.9. The wall pressure transducers were positioned in the streamwise direction parallel to the jet centerline on the plate surface, including one position upstream of the nozzle exhaust. The pressure transducers in the spanwise direction were positioned close to the plate trailing edge. Data analyses were performed using multivariate statistical quantities in the time and frequency domains. Furthermore, application of the wavelet transform has been chosen to understand the relative contribution of turbulent boundary layer and jet shear layer pressure fields on the scattered far-field noise. Wall pressure data will be also correlated with the far field signals illustrating the propagation effects of the detected wall pressure signatures.

RESUMO Aborda-se neste texto a constituição de articulações urbanas que extrapolam a dimensão metropolitana, espraiando-se de forma dispersa em escala regional, utilizando como estudo de caso a formação de um “corredor urbano” entre Campinas e Sorocaba, duas cidades polos de regiões metropolitanas no interior do Estado de São Paulo, Brasil. Constata que o sistema de transporte regional articula a configuração de um eixo de conurbação linear entre as duas regiões metropolitanas, ao longo do qual há uma intensa dinâmica de transformação espacial com o rápido avanço do tecido urbano – especialmente nas tipologias de condomínios industriais e loteamentos residenciais fechados – sobre áreas rurais. Demonstra-se assim, uma nova tendência de concentração linear da dispersão urbano-regional no contexto de uma urbanização extensiva que se manifesta em vetores privilegiados em relação à afluência de investimentos, principalmente dos setores produtivos mais vinculados à economia globalizada, confrontando as tradicionais divisões conceituais entre urbano/rural, cidade/região, centro/periferia. ABSTRACT This paper is about the constitution of urban articulations extended beyond the metropolitan scale, spreading in a dispersed pattern on a regional scale, using the formation of an “urban corridor” between Campinas and Sorocaba, two core-cities of distinct metropolitan areas in the interior of the State of São Paulo as case studies. The regional transport system is the element that articulates the configuration of a linear axis of conurbation between the two metropolitan areas, during which there is an intense spatial transformation with the quick advance of the urbanized areas – especially in the types of gated communities – over rural areas. This shows a new trend of linear concentration of regional dispersion of urban areas in some privileged vectors, in relation to the inflow of investments, mainly of the productive sectors linked to the globalized economy, confronting the traditional conceptual divisions between urban/rural, city/region, center/periphery.

This paper analyzes the conception of the Vetor de Desenvolvimento Perimetral (Perimetrical Development Vector) of the São Paulo Macrometropolis as a linear axis of regional planning, which has been privileged by the spatial reorganization of the productive structure of the State of São Paulo. The collected data demonstrates that the state planning agencies have made huge investments in the interregional transport infrastructures, in order to provide this regional axis - between Sorocaba, Campinas, São José dos Campos and the port of São Sebastião - with excellent conditions to attract the most modern sectors of contemporary industry to the location, and thus consolidate it as the main corridor of production and flow of goods related to the new industrial standards. Resumo Analisa-se, neste artigo, a concepção do Vetor de Desenvolvimento Perimetral da Macrometrópole Paulista como um eixo linear de planejamento territorial privilegiado na reorganização espacial da estrutura produtiva paulista. Os dados apresentados demonstram que há, por parte dos órgãos estaduais de planejamento do Estado, um grande volume de investimentos em infraestruturas de transporte inter-regional, cujo objetivo é dotar esse eixo territorial entre Sorocaba, Campinas, São José dos Campos e o porto de São Sebastião de ótimas condições para atrair a localização dos setores mais modernos da indústria contemporânea e, por conseguinte, consolidá-lo como o principal corredor de produção e escoamento de mercadorias relacionadas aos novos padrões industriais/logísticos.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES O estágio contemporâneo de urbanização indica, nos locais de maior densidade técnica, a particularidade de configuração de fenômenos espaciais urbanos em escala regional que transcendem as tradicionais noções dicotômicas de cidade/região, urbano/rural e centro/periferia, a partir da formação de arranjos urbano-regionais que ocorrem a partir da articulação entre históricas centralidades urbanas concentradas e recentes núcleos urbanos espacialmente dispersos e descontínuos. Neste contexto urbano-regional, esta pesquisa aponta para o surgimento de vetores lineares interregionais como elementos principais de reconcentração territorial da produção e da urbanização, tendo como estudo de caso a formação de um eixo de conurbação linear entre Campinas-Sorocaba ao longo da rodovia SP-75. Optou-se por denominar tal fenômeno como um “corredor urbano”, terminologia associada diretamente à fluidez característica à organização espacial contemporânea deste vetor estruturado por infraestrutura de transporte e circulação. Trabalha-se sobre a hipótese de que a formação do Corredor Urbano Campinas-Sorocaba explicita a constituição de territórios contínuos derivados da interação técnico-econômica sobre a pulverização das articulações regionais históricas, promovida por uma aliança entre o poder público e os agentes privados na gestão e produção do espaço. Com base na leitura da expansão urbana recente neste vetor, objetiva-se demonstrar a intensificação da disputa pela produção do espaço urbano no CUCS como principal decorrência espacial da formação dos vetores urbano-regionais no território paulista. The contemporary stage of urbanization indicates the particularity of the configuration of urban phenomena on a regional scale that transcend traditional dichotomous notions of city/region, urban/rural and center/periphery, based on the formation of urban-regional arrangements between historical concentrated urban centralities and spatially dispersed and discontinuous new urbanizations. In an urban-regional context this research points to the composition of linear interregional vectors as the main element of territorial re-concentration of production and urbanization, taking the form of a linear conurbation axis between Campinas- Sorocaba, along the SP highway -75, as a case study. It has been deemed as the “urban corridor”, a term used to demonstrate the phenomenon, as it is directly associated to the fluid-like characteristic of the contemporary spatial organization of this vector, that is structured by transport and circulation infraestructure. We work on the hypothesis that the formation of the Campinas-Sorocaba Urban Corridor explicitly makes the constitution of continuous territories derived from the technical-economic interaction on the pulverization of historical regional articulations, which is promoted by an alliance between the public power and the private agents in the management and production of space. Based on the analysis of recent urban expansion in this vector, we aim to demonstrate the intensification of the dispute over the production of urban space in the CUCS, as the main spatial consequence of the formation of urbanregional vectors in the territory of São Paulo.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior The purpose of this work is to study and characterize aerodynamically a free jet operating at subsonic regime and identify its acoustic signature. This study aims to analyze fundamentally the turbulent structures and the total noise produced at different Mach numbers. This kind of research is crucial to the understanding of these mechanisms of noise generation and propagation, and it is extremely important for aeronautical applications, for instance, the jet engine exhaust. The research is done by analysing the data obtained in experiments using pitot tube, hot-wire anemometer and acoustic measurements. This work also describes the experimental procedures for each step of analysis, as well as the characteristics of jet noise facilities. The data from measurements with a pitot tube was used to study the mean velocity profiles. The average properties are also analyzed with an anemometry system, likewise used to study the turbulent intensity at eleven axial lines, ranging from the centerline to the edge of the nozzle (lipline). These results are compared with literature and has verified the accuracy of hot-wire anemometers for turbulent intensities lower than 15%. The aerodynamic data are obtained for Mach numbers 0.25, 0.50 and 0.75, from the nozzle exit to thirteen diameters in the direction of the jet. The acoustic study is carried out by analyzing the sound pressure level obtained at six positions in the far field, with observer angles ranging from 40 to 110º. In this campaign more velocities are studied with Mach numbers from 0.18 to 1.00 with step of 0.05 are described. A database with the sound pressure level as a function of frequency is constructed from this information. O objetivo deste trabalho é estudar e caracterizar aerodinamicamente um jato livre operando em regime subsônico e identificar a assinatura acústica do mesmo. Esse estudo busca analisar fundamentalmente as estruturas turbulentas e o ruído total produzido em diferentes números de Mach. Tal estudo é crucial para o entendimento desses mecanismos de geração e propagação, e encontra extrema importância para aplicações aeronáuticas, como, por exemplo, a exaustão de motores a reação (jato). A investigação é feita através da análise dos dados obtidos em experimentos utilizando tubo de pitot, anemômetro de fio-quente e ensaios acústicos. Neste trabalho também são descritos os procedimentos experimentais de cada etapa de análise, bem como as características dos laboratórios utilizados para o estudo do ruído de jato. Com os dados provenientes das medições com tubo de pitot são estudados os perfis de velocidade média. As propriedades médias também são analisadas com o sistema de anemometria, que ainda é utilizado para estudo da intensidade turbulenta em onze linhas axiais, variando da linha de centro até a borda do bocal (lipline). Estes resultados são comparados com a literatura e é constatada a acurácia dos anemômetros de fio-quente para intensidades turbulentas menores que 15%. Os dados aerodinâmicos mencionados são obtidos para números de Mach 0,25, 0,50 e 0,75, a partir da saída do bocal até treze diâmetros na direção do jato. O estudo acústico é feito através da análise do nível de pressão sonora obtido em seis posições no campo distante, com ângulos de observação variando de 40 a 110º. Diferentes velocidades também foram analisadas, desta vez, com números de Mach de 0.18 a 1.00 com passo de 0.05. Um banco de dados com o nível de pressão sonora em função da frequência é construído a partir destas informações. Mestre em Engenharia Mecânica