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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Určení rozložení teploty oblouku v reálném jističi / Determination of the Temperature Field in a Real Circuit Breaker

Pěček, Dominik January 2017 (has links)
This master thesis deals with determination of temperature field in a real circuit breaker. This issue is solved by analysis of measured emission spectra at selected points of the circuit breaker. Spectral line ratios and Boltzmann plot are used for calculation of temperature. These methods are based on elemental analysis of plasma. The main result is finding significant changing of chemical composition of plasma beyond determination of temperature field.
82

Krav på kundägd anslutningspunkt med produktionsanläggning / Requirement for customer-owned connection point with production plant

Andreasson, Johan, Fåll, Fabian January 2023 (has links)
Vattenfall Eldistribution AB är en av Sveriges största nätägare och har som mål att få Sverige fossilfritt inom en generation. För att täcka Sveriges elenergibehov på ett fossilfritt sätt krävs det fler förnybara produktionsanläggningar. En av de produktionsanläggningarna som växer mest just nu är solcellsanläggningar. Svenska standarder har regler för hur produktionsanläggningar ska utformas. Det ställs bland annat krav på hur den manuella frånkopplingen ska fungera och att det måste finnas en brytare som kan frånskilja hela produktionsanläggningen, även kallad produktionsbrytare. På grund av olika tolkningar har denna brytare kunnat placeras på olika sätt, men nu vill Vattenfall Eldistribution AB med hjälp av detta arbete ta fram ett standardiserat sätt att placera produktionsbrytaren på. Därför var huvudmålet med arbetet att ta fram riktlinjer för hur kunder till Vattenfall Eldistribution AB ska placera produktionsbrytaren i anläggningen. Arbetet presenterar en övergriplig beskrivning över hur en solcellsanläggning kan se ut samt hur mängden av dessa anläggningar i Sverige har förändrats. Då statistiken visat att antalet produktionsanläggningar ökat varje år blir det allt viktigare att det finns tydligare riktlinjer från nätägare. Dessutom undersöks hur Vattenfall Eldistribution AB behandlar en förfrågan att installera solceller. Genom beräkningar av elnätet avgörs hur anslutningen av produktionsanläggningen kommer att gå till. För att uppnå ett resultat krävdes det att ta in information från flera källor. Vattenfall Eldistribution AB delade med sig av vad som var viktigt för dem och hur de önskar att installationerna är utformade. Som komplement till Vattenfall Eldistribution AB:s yttrande granskades relevanta standarder och föreskrifter. För att ytterligare motivera placeringen till kunder har hänsyn tagits till brandkårens önskemål om solcellsanläggningar. Baserat på informationen från samtliga källor togs riktlinjer fram. Dessa riktlinjer presenterar olika placeringar av produktionsbrytaren. För varje placering beskrivs fördelar och nackdelar. Slutsatserna av arbetet är att produktionsbrytaren behöver placeras utomhus, antingen på byggnadens fasad alternativt i mätarskåpet om det befinner sig utomhus. Utöver placeringen av produktionsbrytaren behöver även växelriktaren till anläggningen uppfylla de krav som ställs av förordningar vilket lättast görs genom att välja en växelriktare som är med i listan ”Rikta Rätt” från Energiföretagen. / Vattenfall Eldistribution AB is one of Sweden's largest grid owners and aims to make Sweden fossil-free within one generation. In order to cover Sweden's electrical energy needs in a fossil-free way, more renewable production plants are required. One of the production plants that is growing the most right now is solar cell plants. Swedish standards have rules for how production plants must be designed. Among other things, there are requirements on how the manual disconnection of the solar cells should work and that there must be a circuit breaker that can disconnect the entire production plant, also called a production circuit breaker. Due to different interpretations, this circuit breaker has been allowed to be placed in different ways, but now Vattenfall Eldistribution AB wants to use this work to develop a standardized way to install the production circuit breaker. Therefore, the main goal of the work has been to produce guidelines for how customers of Vattenfall Eldistribution AB should place the production circuit breaker in the plant. The work presents a comprehensive description of what a solar cell installation might look like and how the amount of these facilities have changed in Sweden. As the statistics show that the number of production facilities increases every year, it is important that there are clearer guidelines from grid owners. In addition, how Vattenfall Eldistribution AB handles a request to install solar panels has been investigated. Through calculations of the electricity network, it is determined how the connection of the production plant will be carried out. In order to achieve a result, it was necessary to gather information from several sources. Vattenfall Eldistribution AB shared what was important to them and how they would like the installations to be designed. As a supplement to Vattenfall Eldistribution AB's opinion, relevant standards and regulations were examined. In order to further justify the placement to customers, consideration was also given to the fire department's requests for solar cell installations. Based on the information from all sources, guidelines were created. These guidelines present different locations of the production circuit breaker. For each location the advantages and disadvantages are described. The conclusions of the work are that the production circuit breaker needs to be placed outdoors, either on the facade of the building or alternatively in the meter cabinet if it is outdoors. In addition to the location of the production circuit breaker, the inverter for the plant also needs to meet the requirements set by regulations, which is done by choosing an inverter that is on the list of "Rikta Rätt" from Swedenergy.
83

Chip Breaking Optimization During Turning Shoulder / Optimerad spånbrytning vid svarvning

YANG, XINYI January 2017 (has links)
Poor chip breaking is a normal problem in the field of machining in many manufacturing plants. The researches on chip control has started from the early 1900s, it has developed for more than one hundred years and researchers are still working on it to establish a ‘total’ chip control system. The purpose of this project is chip breaking improvement for reducing downtime and further increasing OEE, because of the problems long chips that cause during a soft turning process. This thesis provides basic theories and existing methods for chip breaking which are helpful to understand chip breaking and to generate solutions for chip breaking optimization. During the project, five concepts are generated and two concepts are tested which are presented in this report. The concept ‘multiple tool paths’, which was verified by tests, could successfully reduce the length of metal chips and improving the performance of chip breaking. / Dålig spånbrytning är ett vanligt problem vid maskinbearbetning i många tillverkningsanläggningar. Forskningen om spånbrytning inleddes under tidigt 1900-tal, den har alltså utvecklats i mer än hundra år och forskare arbetar fortfarande med att skapa ett "totalt" spånbrytningssystem. Syftet med det här projektet är att förbättra spånbrytningen för att minska ledtiden och ytterligare öka OEE vid mjukvarvning på grund av de problem som långa chips orsakar. Denna avhandling behandlar grundläggande teorier och befintliga metoder för spånbrytning som är användbara för att förstå spånbrytning och därmed kunna föreslå lösningar för att optimera spånbrytningen. Under projektet skapades fem koncept, varav två provades. Konceptet "flera verktygsbanor" verifierades genom prov. Det visas att det konceptet med framgång kunde minska längden på metallchip och förbättra spånbrytningens prestanda.
84

Dynamics of an ultra-fast Thomson actuated HVDC breaker / Dynamik för en ultra-snabb Thomson-aktiverad HVDC-brytare

Álvarez Sánchez, Miguel January 2017 (has links)
High Voltage Direct Current (HVDC) is a rapidly growing form of power transmission that offers advantages with respect to conventional AC networks. One of the key elements that will allow the generalization of the HVDC grids is the Circuit Breaker (CB), which has to interrupt high DC currents in extremely short times. The use of a Thomson coil (TC) to generate high driving forces is being considered as a suitable working principle for the mechanical actuator inside the CB. This thesis presents the design of a concept of a mechanical actuator based on the Thomson coil for SCiBreak AB, a company whose final objective is to create a complete ultra-fast circuit breaker for HVDC lines. The design phase had to face challenges with the high forces required to open a gap between electrical contacts in just a few milliseconds. A detail design for the different components of the actuator was performed and analytical and CAD models of the system were generated. This thesis also included the construction and testing of a prototype at the company’s premises. The final output was the analysis and discussion of the experimental results of the prototype, as well as suggestions for the future development of the mechanical actuator. / Högspänd likström (HVDC, från engelskans High Voltage Direct Current) är en snabbt växande form av kraftöverföring som har många fördelar jämfört med konventionella växelströmsnätverk. Ett av huvudelementen i nätet är strömbrytaren (CB, från engelskans Circuit Breaker), vilken möjliggör avbrott i de höga likströmmarna på extremt korta tider. Användandet av en Thomson-spole (TC, från engelskans Thomson Coil) för att generera höga drivkrafter anses vara en lämplig arbetsprincip för manöverdonet inuti CB. I detta projekt konstruerades ett koncept av ett mekaniskt manöverdon baserat på Thomson-spolen för SCiBreak AB, ett företag vars slutliga mål är att skapa en komplett ultrasnabb strömbrytare för HVDC-linjer. Designfasen mötte utmaningar med de höga krafter som krävs för att öppna ett gap mellan elektriska kontakter på bara några millisekunder. En detaljdesign för de olika komponenterna i manöverdonet utfördes och analytiska och CAD-modeller av systemet genererades. Projektet omfattade också tillverkning och provning av en prototyp i företagets lokaler. Slutprodukten var en analys och en diskussion av prototypens experimentella resultat samt förslag till framtida utveckling av det mekaniska manöverdonet.
85

Hierarchical control scheme for multi-terminal high voltage direct current power networks / Commande hiérarchique de réseaux multi-terminaux à courant continu et haute tension

Jimenez Carrizosa, Miguel 10 April 2015 (has links)
Cette thèse traite de la commande hiérarchique de réseaux à courant continu multi-terminaux à haute tension (MT-HVDC) intégrant des sources d'énergie renouvelables à grande échelle. Le schéma de contrôle proposé est composé de quatre ‘couches’ : le contrôle local où se trouvent les convertisseurs de puissance, avec une échelle de temps de l’ordre de la milliseconde ; le contrôle primaire qui est décentralisé et appliqué à plusieurs terminaux avec une échelle du temps de l’ordre de la seconde ; un niveau de commande où la communication est prise en compte et où l’approche de Modèle du Commande Prédictive (MPC) assure la planification de la tension et de la puissance à leur état d'équilibre, pour l'ensemble du système; enfin, le contrôleur de niveau supérieur, qui est principalement basé sur les techniques d'optimisation, où les aspects économiques sont pris en compte (il s’agit du réglage dit tertiaire).Au niveau des convertisseurs, un accent particulier est mis sur les convertisseurs bidirectionnels DC/DC. Dans cette thèse, trois topologies différentes sont étudiées en profondeur: deux phases Dual Active Bridge (DAB), trois phases DAB, et l’utilisation de la technologie Modular Multilevel converter (MMC) comme convertisseur DC/DC. Pour chaque topologie, une commande non-linéaire spécifique est discutée. D’autre part une nouvelle fonction pour le convertisseur DC/DC est étudiée. Il s’agit de son utilisation comme disjoncteur à courant continu (DC-CB). En ce qui concerne le contrôle primaire, qui permet de maintenir le niveau de tension continue dans le réseau, nous avons étudié trois philosophies de contrôle: celle de maître/esclave, celui du contrôle « voltage margin control » et celle de la commande du statisme (droop control). Enfin, nous avons choisi d'utiliser le droop control, entre autres, parce que la communication entre les nœuds n’est pas nécessaire. Concernant la commande secondaire, son principal objectif est de planifier le transfert de puissance entre les nœuds du réseau, qui fournissent la tension et la puissance de référence aux contrôleurs locaux et primaires, même lorsque des perturbations apparaissent. Dans cette partie, nous avons proposé une nouvelle approche pour résoudre les problèmes de flux de puissance (équations non-linéaires) basée sur le théorème du point fixe de l’application contractive. Ceci permet d'utiliser plus d'un slack bus, contrairement à l’approche classique basée sur la méthode de Newton-Raphson. Par ailleurs, le réglage secondaire joue un rôle très important dans les applications pratiques, en particulier lorsque les sources d'énergie renouvelables (variables dans le temps). Dans de tels cas, il est intéressant de considérer des dispositifs de stockage afin d'améliorer la stabilité de tout le système. Il est également possible d'envisager différents types de prévisions (météo, charge, ..) basées sur la gestion des réserves de stockage. Toutes ces caractéristiques ont suggéré l'utilisation d'une approche MPC. Dans ce contexte, plusieurs critères d'optimisation ont été considérés, en particulier la minimisation des pertes de transmission ou des congestions dans le réseau.La tâche principale de réglage tertiaire est de d'atteindre l'optimisation économique de l'ensemble du réseau. Dans cette thèse, nous avons pu maximiser le profit économique du système en agissant sur le marché réel, et en optimisant l'utilisation des périphériques de stockage. Dans le but de mettre en œuvre la philosophie de contrôle hiérarchique présentée dans cette thèse, nous avons construit un banc d'essai expérimental. Cette plate-forme dispose de quatre terminaux reliés entre eux par l'intermédiaire d'un réseau à courant continu, et connectés au réseau principal de courant alternatif. Ce réseau DC peut fonctionner à un maximum de 400 V, et avec une courant maximal de 15 A. / This thesis focuses on the hierarchical control for a multi-terminal high voltage direct current (MT-HVDC) grid suitable for the integration of large scale renewable energy sources. The proposed control scheme is composed of 4 layers, from the low local control at the power converters in the time scale of units of ms; through distributed droop control (primary control) applied in several terminals in the scale of unit of seconds; and then to communication based Model Predictive Control (MPC) that assures the load flow and the steady state voltage/power plan for the whole system, manage large scale storage and include weather forecast (secondary control); finally reaching the higher level controller that is mostly based on optimization techniques, where economic aspects are considered in the same time as longer timespan weather forecast (tertiary control).Concerning the converters' level, special emphasis is placed on DC/DC bidirectional converters. In this thesis, three different topologies are studied in depth: two phases dual active bridge (DAB), the three phases DAB, and the use of the Modular Multilevel Converter (MMC) technology as DC/DC converter. For each topology a specific non-linear control is presented and discussed. In addition, the DC/DC converter can provide other important services as its use as a direct current circuit breaker (DC-CB). Several operation strategies are studied for these topologies used as DC-CB.With respect to primary control, which is the responsible to maintain the DC voltage control of the grid, we have studied several control philosophies: master/slave, voltage margin control and droop control. Finally we have chosen to use droop control, among other reasons, because the communication between nodes is not required. Relative to the secondary control, its main goal is to schedule power transfer between the network nodes providing voltage and power references to local and primary controllers, providing steady state response to disturbances and managing power reserves. In this part we have proposed a new approach to solve the power flow problem (non-linear equations) based on the contraction mapping theorem, which gives the possibility to use more than one bus for the power balance (slack bus) instead of the classic approach based on the Newton-Raphson method. Secondary control plays a very important role in practical applications, in particular when including time varying power sources, as renewable ones. In such cases, it is interesting to consider storage devices in order to improve the stability and the efficiency of the whole system. Due to the sample time of secondary control is on the order of minutes, it is also possible to consider different kinds of forecast (weather, load,..) and to achieve additional control objectives, based on managing storage reserves. All these characteristics encourage the use of a model predictive control (MPC) approach to design this task. In this context, several possibilities of optimization objective were considered, like to minimize transmission losses or to avoid power network congestions.The main task of tertiary control is to manage the load flow of the whole HVDC grid in order to achieve economical optimization. This control level provides power references to the secondary controller. In this thesis we were able to maximize the economic profit of the system by acting on the spot market, and by optimizing the use of storage devices. In this level it is again used the MPC approach.With the aim of implementing the hierarchical control philosophy explained in this thesis, we have built an experimental test bench. This platform has 4 terminals interconnected via a DC grid, and connected to the main AC grid through VSC power converters. This DC grid can work at a maximum of 400 V, and with a maximum allowed current of 15 A.
86

The effectiveness of the 'place of effective management' tie-breaker rule in the OECD Model Tax Convention / by K. Luker

Luker, Karen January 2010 (has links)
Double taxation could arise in a situation where resident- resident conflicts occur. Resident–resident conflicts occur in the situation where both countries regard such a person as a “resident” for tax purposes under their domestic legislation. For that reason, all income that is earned by that person, irrespective of the jurisdiction it is earned in, will be subject to tax in both countries. In order to resolve these conflicts, the Organisation for Economic Cooperation and Development’s (“OECD’s”) Model Tax Convention contains a tie breaker clause which states that a non-individual shall be deemed to be a resident only of the State in which the ‘place of effective management’ is situated. It was found that although there were conflicting views, the expression ‘place of effective management’ was mainly determined with reference to the place where real management actually makes decisions on key business affairs of the company. Based on the following reasons it was concluded that using ‘place of effective management’ as a tie breaker rule was ineffective. • With improved communication technology and increased mobility of top level management, it makes it very difficult to pinpoint a single location where the ‘place of effective management’ is positioned; • Changes to the generic managerial structures seen in the past, makes it increasingly complex to determine where the ‘place of effective management’ is situated; and • There is no universal interpretation of the term ‘place of effective management’ within the international arena. Against the backdrop that each option for determining the ‘place of effective management, analysed in Chapter 4 had its own flaws, it is almost impossible to determine a company’s residency based on a single test. It was therefore, recommended that the tie breaker rule consist of a hierarchy of the following tests. 1. Deemed to be resident of the country in which place of effective management is situated, as defined by SARS’ interpretation. 2. Deemed to be a resident of the country in which its economic nexus is the strongest. 3. Conflict to be resolved by mutual agreement between the two Contracting States. / Thesis (M.Com. (Tax))--North-West University, Potchefstroom Campus, 2011.
87

The effectiveness of the 'place of effective management' tie-breaker rule in the OECD Model Tax Convention / by K. Luker

Luker, Karen January 2010 (has links)
Double taxation could arise in a situation where resident- resident conflicts occur. Resident–resident conflicts occur in the situation where both countries regard such a person as a “resident” for tax purposes under their domestic legislation. For that reason, all income that is earned by that person, irrespective of the jurisdiction it is earned in, will be subject to tax in both countries. In order to resolve these conflicts, the Organisation for Economic Cooperation and Development’s (“OECD’s”) Model Tax Convention contains a tie breaker clause which states that a non-individual shall be deemed to be a resident only of the State in which the ‘place of effective management’ is situated. It was found that although there were conflicting views, the expression ‘place of effective management’ was mainly determined with reference to the place where real management actually makes decisions on key business affairs of the company. Based on the following reasons it was concluded that using ‘place of effective management’ as a tie breaker rule was ineffective. • With improved communication technology and increased mobility of top level management, it makes it very difficult to pinpoint a single location where the ‘place of effective management’ is positioned; • Changes to the generic managerial structures seen in the past, makes it increasingly complex to determine where the ‘place of effective management’ is situated; and • There is no universal interpretation of the term ‘place of effective management’ within the international arena. Against the backdrop that each option for determining the ‘place of effective management, analysed in Chapter 4 had its own flaws, it is almost impossible to determine a company’s residency based on a single test. It was therefore, recommended that the tie breaker rule consist of a hierarchy of the following tests. 1. Deemed to be resident of the country in which place of effective management is situated, as defined by SARS’ interpretation. 2. Deemed to be a resident of the country in which its economic nexus is the strongest. 3. Conflict to be resolved by mutual agreement between the two Contracting States. / Thesis (M.Com. (Tax))--North-West University, Potchefstroom Campus, 2011.
88

企業併購流程與評價之個案研究分析 / A Case Study on the M&A Process and Valuation

盧圜玉, Lu, Kelly Unknown Date (has links)
This thesis aims at understanding the M&A process from the beginning of strategy development, target screening, transaction execution, to integration and reorganization. On the buy side perspective knowing that during each process what are the key points and issues that a buyer/acquirer will encounter and fully prepare for it. In order to make a successful deal, a company must have a clear plan to fit its corporate strategy under the help with advisors toward the direction by using M&A as a choice to make expansion. It gives a successful first-timer deal making case study given that the buyer and seller’s company background, the motive behind this merge and the process. In addition to the overview of the case study it also identifies key issues during the transaction execution process. Finally it comes up with a synergy analysis to prove that why this deal is making a success. M&A is a complex topic involving with many business aspects and therefore in order to avoid failing, specific deal breakers should be careful during the process. There is a saying from Sun Tzu “know yourself, know your enemy, and you shall win a hundred battles without loss” and this is the right attitude toward an M&A deal in considering every issues that might have happened.
89

Análise da aplicabilidade de sensores de acoplamento capacitivo no monitoramento de disjuntores de alta tensão.

SANTANA, Henrique Nunes de. 17 April 2018 (has links)
Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2018-04-17T13:51:49Z No. of bitstreams: 1 HENRIQUE NUNES DE SANTANA – DISSERTAÇÃO (PPGEE) 2017.pdf: 2930914 bytes, checksum: a4c0e297d62f2854c085762512fb6f16 (MD5) / Made available in DSpace on 2018-04-17T13:51:49Z (GMT). No. of bitstreams: 1 HENRIQUE NUNES DE SANTANA – DISSERTAÇÃO (PPGEE) 2017.pdf: 2930914 bytes, checksum: a4c0e297d62f2854c085762512fb6f16 (MD5) Previous issue date: 2017-08-18 / Capes / Neste trabalho, é avaliada aplicabilidade de sensores de acoplamento capacitivo na detecção dos sinais emitidos por arcos elétricos em contatos de disjuntores. Adicionalmente, é investigada a possibilidade de correlacionar estes sinais com nível de degradação dos contatos de arco. A aplicabilidade dos sensores é avaliada por meio da comparação dos sinais detectados pelos mesmos, com os sinais detectados por uma antena direcional em banda larga, tanto no domínio do tempo quanto no domínio da frequência. Para a análise da correlação entre o nível de degradação dos contatos de arco e os sinais detectados, atributos de estatística descritiva da duração e da energia dos sinais foram avaliados. A análise dos resultados evidenciou que os sensores de acoplamento capacitivo são capazes de detectar os sinais emitidos pelos arcos elétricos. Também foi evidenciado que a sensibilidade de detecção dos sensores depende da posição na qual foram instalados ao longo do polo analisado. No caso dos disjuntores utilizados neste trabalho, a melhor posição para a instalação dos sensores foi a posição mais próxima do terminal inferior do polo. A flexibilidade e o valor da constante dielétrica devem ser avaliados no momento da escolha do material empregado na confecção dos sensores, uma vez que sensores pouco flexíveis podem sofrer danos ao serem instalados no polo do disjuntor e, constantes dielétricas elevadas podem prejudicar os ganhos dos respectivos sensores. A correlação entre os sinais dos arcos elétricos detectados pelos sensores e o nível de degradação dos contatos de arco é possível, quando os atributos estatísticos da média, desvio padrão, curtose e mediana obtidos da energia dos referidos sinais são avaliados. / In this work, is evaluated the applicability of capacitive coupling sensors in the detection of signals emitted by electric arcs in circuit breaker contacts. In addition, the possibility of correlating these signals with the arcing contacts degradation level is investigated. The sensors applicability is investigated by comparing the signals detected by them with the signals detected by a broadband directional antenna in both time and frequency domain. For the analysis of the correlation between the arcing contacts degradation level and the detected signals, descriptive statistical attributes of the duration and energy of the signals were evaluated. The analysis of the results showed that the capacitive coupling sensors are able to detect the signals emitted by the electric arcs. It was also evidenced that the sensor detection sensitivity depends on the position in which they are installed along the analyzed pole. In the case of the circuit breakers used in this work, the best position for the installation of the sensors was the one closest to the lower terminal of the pole. The flexibility and value of the dielectric constant must be evaluated when choosing the material used in the construction of the sensors, since weak sensors can be damaged when installed at the pole of the circuit breaker, and high dielectric constants can affect the gains of the respective sensors. The correlation between the electric arcs signals detected by the sensors and the arcing contacts degradation level is possible, when the statistical attributes of the mean, standard deviation, kurtosis and median obtained from the energy of these signals are evaluated.
90

Avaliação do desempenho termico de tres tipologias de brise-soleil fixo / Thermal performance of three different fixed shading devices

Gutierrez, Grace Cristina Roel 12 March 2004 (has links)
Orientador: Lucila Chebel Labaki / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-07T10:20:33Z (GMT). No. of bitstreams: 1 Gutierrez_GraceCristinaRoel_M.pdf: 13332804 bytes, checksum: 2e59e6bab72a64cce872302835c70d3c (MD5) Previous issue date: 2004 / Resumo: Esta pesquisa avalia o desempenho térmico do brise-soleil, em relação à radiação solar incidente em ambientes com aberturas protegidas. Os dispositivos testados foram selecionados considerando as tipologias e materiais utilizados em edificações da arquitetura moderna brasileira entre os anos 1930 e 1960. O desempenho térmico do brise-soleil é reconhecido em estudos de geometria de insolação e simulação com software, porém são raras as avaliações experimentais sob condições climáticas reais. A metodologia utilizada é baseada em pesquisas de desempenho térmico de elementos e componentes construtivos realizadas em protótipos. Através de um sistema de aquisição de dados são verificadas: variáveis ambientais (temperatura do ar, umidade relativa, radiação solar, pluviosidade, direção e velocidade dos ventos), e variáveis medidas nos protótipos (temperaturas do ar e superficiais). Os ensaios de campo foram realizados em protótipos localizados em Campinas, SP. Foram testados brise-soleil horizontal e vertical em madeira e concreto, e elemento vazado (concreto), fixos, expostos nas fachadas norte ou oeste, durante uma semana em cada orientação, nos períodos próximos aos equinócios e solstícios de verão e inverno. Nos ensaios realizados, os resultados mostraram a redução pontual de até 4,14ºC na temperatura interna, sendo o melhor desempenho térmico o da tipologia combinada. O brise-soleil vertical fixo perpendicular à fachada apresentou os piores resultados na fachada oeste, contrariando indicações usuais da literatura arquitetônica / Abstract: In this work the thermal performance of shading devices regarding solar radiation in indoor spaces with protected openings is analyzed. The typology and materials of shading devices were selected considering the elements used in Brazilian modern architecture buildings between the 1930 and 1960 decades. Most studies about shading devices are based on geometric drawings and software simulation analyzing the efficiency of provided protection during specific periods, however there are few experimental works performed under real climate conditions. In this investigation, three different devices were evaluated in the most problematic conditions of exposure, by acquiring measurable data of external parameters (air temperature, relative humidity, solar radiation, rain, wind speed and direction) and internal parameters (air temperature and surface temperatures) to verify their efficiency. These experiments were conducted at School of Civil Engineering, Architecture and Urban Design of State University of Campinas (UNICAMP) in the State of São Paulo, Brazil. The investigated devices were horizontal and vertical sun-breakers of concrete and wood, and concrete eggcrate sunbreaker, fixed, on north and west exposures, for a week in each façade, in equinox and summer and winter solstices periods. In these tests, the eggcrate typology showed the best thermal performance, with a punctual reduction of up to 4,14ºC on internal air temperature. The vertical fixed devices registered the worst results on west façade, in contrast with current Brazilian architectural literature recommendation / Mestrado / Edificações / Mestre em Engenharia Civil

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