Colheita de energia usando dispositivos baseados em materiais piezoelétrico

Recently, research on energy harvesting has increased substantially. Many researchers have concentrated their efforts to find the best configuration for these systems and to optimize their output power. In the process of energy harvesting, the electric energy is obtained by converting mechanics energy created by an environment vibration source by a transducer, for example, a thin piezoceramic film. That vibration source is, for example, a beam suffering some mechanic force able to generate a vibration in it, an oscillating beam is the best properly used example. Different mechanisms of electromechanical coupling have been developed to harvesting devices, and a particular interest has been given to the use of models that transform the mechanical vibration into electrical current using a piezoelectric element. In this paper we propose a model to energy harvesting from vibrations, from an oscillating beam, including non-linearities in the piezoelectric coupling and a non-ideal excitation in the material. From this model, it was developed a system to obtain some results about the harvested power by the material. It was demonstrated that the power captured was influenced by the effect of the nonlinearities of the piezoelectric coupling, modifying the system dynamic behavior

Comercialização de energia elétrica no Brasil

How companies can sell their surplus production capacity of electric power in Brazil? This work was developed from the question presented and focusing on clarification of procedures to enter the Brazilian electricity market by providing basic guidelines based on resolutions by National Agency of Electric Energy, National System Operator procedures and rules of the Assembly of Electric Energy Commercialization. It features subsidy to companies that fit this profile to evaluate the possibility to sell their surplus electricity. The general aim was to analyze the procedures and the necessary steps to make this sale happen. Was developed through a literature review where an overview of the Brazilian electric sector and a case study of a company that has excess capacity of electricity, but doesn’t make its marketing. Resulted in the expected clarification as well as the incentive for companies through the information presented, the entry in this trade since power is still crucial to the country's economic growth and ensure its availability in quantity demanded is a challenge of the utmost importance for satisfactory results are achieved economic development contributing to the progress of our society

Plano de iluminação externa da UNESP Campus Itapeva com base em LED e energia solar

This work presents the development of the External Lighting Plan UNESP in the Itapeva Campus based LED and Solar Energy. Firstly it was made a collection of data from measurements of the local transit through the Google Earth 6 software and divide the local in sectors, and then perform an analysis of characteristics and age of the site. With these data it was possible to determine the average luminance the place, in30 lux. After these procedures was possible to determine the type of sets that would perform the role of bridge lighting the kit chosen was the 20/20 Sun LED manufacturer, since it contains the luminaire with the solar panel to the pole. Therefore we determined the number of poles for each sector, whichwas72in total and. After the determination of the location of each point lighting

Estudo sobre fornos de tratamento térmico e propostas de cogeração de energia em usina siderurgica não integrada

Steel industry is a sector heavily dependent on energy, both electrical and thermal. Since the receipt of raw materials to the shipment of finished products to customers, through mergers, casting, rolling, heat treatment, inspection, among others, high amounts of energy are demanded, generating very significant costs to the productive chain in its entirety . Therefore, any alternative that favors the reduction in energy consumption or barateie the cost of this is very welcome. Within this context, this paper aims to make a technical and economic analysis of installing a cogeneration plant in the field rolling in a non-integrated steel mill. Two configurations are proposed plants, with one being the use of heat from waste gases from furnaces existing in the area mentioned and another with the use of heat from waste gases from an internal combustion engine. Both proposals are evaluated technically and later is done the economic analysis, calculating the financial return (pay back) in relation to the investment required, operation and maintenance of the plant

Energia, suas formas e transformações: uma abordagem contextualizada por meio de material não-formal

Energy is a physical quantity very present in physics. Although extremely useful, its concept is very abstract for most students in high school and college. Identify the presence and form of energy in a given phenomenon is not simple, as there is immediate understanding on the transfer and transformation. This work emphasizes the study of mechanical energy in its different forms as well as the thermal energy, considering the possible transformations between them. To this end, use is mad of toys, exploring its potential as an alternative material to be use in supplement classroom teaching in primary and secondary levels. The proposed use of ludic pedagogy takes into account the author’s experience as an intern project Toy Scientific Department of Physics and its role as mediator in the workshops offered by the project to school at these levels

Geração de energia elétrica a partir da concentração solar

The current world's need for clean and renewable energy sources aligned with the strong Brazilian growth looking to diversify its electric power generation sources, highly dependent on hydropower and petroleum encourages the implementation of technologies that reach this growth with diversity and cleaning. The sun energy source is considered inexhaustible and can meet the demand for energy through thermo solar plants to generate electricity. Several technologies are being studied and developed in the world and they can be used to generate electricity from the solar concentration, but in Brazil its use is still not found commercially. It is therefore essential to understand these technologies and develop knowledge about them so they can be implemented in Brazil. This work brings an overview of the thermo solar generation in Brazil, showing the different technologies and a thermodynamic simulation of one of such technologies considering a hybrid plant with complementary generation biomass, aiming at the generation of 1 MW in the Brazilian Northeast

Análise comparativa entre Brasil e Alemanha sobre autoprodução de energia elétrica residencial

The energy crisis has affected many countries. With the growing warning with the emission in the atmosphere and the lack of resources, the seek for sustainable sources for energy genaration have become even bigger. Some Countries, as Germany, started first in this journey, creating an incentive program to self-generation with renewable sources (wind, photovoltaics, biomass, etc.), giving priority for smaller plants. In Germany the program called EEG started in 2004. In Brazil, since the beggining of 2012, the self-generators did not know how they could be beneficted for self-generation, and self-generation didn't become commun in the country. However, with NR 482, of April 17th, 2012, the parameters were defined, and the self-generator could have a guideline. Therewith, studyies can be redirected for a better knowlegde of the conditions the self-generator will be sujected, in addition to Germany's case as reference to compare with Brazil's case. In this paper these studies are made, focused in wind power (wind turbines) and photovoltaic panels

Inserção do ensino de astronomia como componente importante para a formação continuada de professores

According to the Brazilian National Curriculum Parameters (PCN), the teaching of astronomy must provide subjects to the teaching/learning processes of basic education, acquisition of skills and competencies in order to form a critical, reflective and conscious citizen. Several surveys on teaching astronomy show that some changes need to be made in educational, aiming to provide to participants (students and teachers) of the teaching/learning real and significant conditions of knowledge aiming to astronomy. Thus, by prior construction, implementation and evaluation, of a course on astronomy, thought and implemented by the author in a public school in elementary school and high school in a town in São Paulo state, aimed to this work: know the challenges that teachers face in teaching Astronomy and identify possible contributions in formative processes of these teachers in service. So, the study revealed that teachers have many difficulties to teach the concepts of astronomy because of the deficit in their formations, both in specific and pedagogical knowledge that was the main problem pointed out by them. In view of this, it was possible to say here that the lack of specific knowledge about astronomy and pedagogical knowledge of how to teach this area are two hotspots in the dynamics of these school teachers who have the challenge of teach an area that really do not know

Desenvolvimento de aplicativo de análise técnica e econômica para adaptação de uma roda d’água acionada por cima para geração de energia elétrica no meio rural

The steel type AISI 4130 (ultra-high strength steel) is an alloy of low carbon and its main alloying elements are chromium and molybdenum, which improves the toughness of the weld metal. It has numerous applications, especially where the need for high mechanical strength. It is widely used in equipment used by the aviation industry, such as cradle-tomotor, and this is the motivation for this study. Cots are of fundamental importance, because the engine supports and maintains balance in the fixed landing gear. This equipment is subjected to intense loading cycles, whose fractures caused by fatigue are constantly observed. Will be determined the effects caused by re-welding the structure of aeronautical equipment, and will also study the microstructure of the metal without welding. The studies will be done on materials used in aircraft, which was given to study. The results provide knowledge of microstructure to evaluate any type of fracture that maybe caused by fatigue. Fatigue is a major cause of aircraft accidents and incidents occurred, which makes the study of the microstructure of the metal, weld and re-solder the knowledge essential to the life of the material. The prevention and control of the process of fatigue in aircraft are critical, since the components are subjected to greater responsibility cyclic loading

Análise do consumo de energia elétrica e da eficiência energética em uma indústria de processamento de madeira

In the industries of wood processing (sawmills), where timber is sawn in equipment such as band saws, circular saws, trowel, thicknessers, among others, that mechanically transform this resource and use of electric motors, which are not unusually poorly scaled working or overloaded, often a factor that is not found in these industries and has fundamental importance in the production process is energy efficiency that is achieved by both technological innovation and through all the practices and policies that aim to lower energy consumption, lowering energy costs and increasing the amount of energy offered no change in generation. For both during the design of an electrical installation, both overall and in various sectors of the installation, investigations are necessary, considerations and uses of variables and factors that put into practice the theme of energy efficiency. Therefore, in this paper, these factors were calculated and analyzed for a wood processing industry (sawmill) in the municipality of Taquarivaí - SP, namely: active power, power factor, demand factor and load factor. Where they were small in relation to the literature, these events that occur when devices are connected at the same time and due to the conditions of processing the wood, where the engines have large variations in electricity consumption during the unfolding of the same, due to efforts with the load and idle moments between each machining operation in the equipment

Estudo da deposição de energia das radiofrequências através do método das diferenças finitas dependentes do tempo Monografia

Radiotherapy in veterinary practice is already known and widely distributed in large specialized centers of developed countries. In early 2000, there were about 30 radiotherapy equipment specifically designed for the veterinary clinic in the United States. In Brazil, the veterinary radiotherapy is still confined to research in universities, where most of the procedures is radiation therapy performed with superficial x-ray machines, with a voltage between 50 and 150 kVp, focus-distance surface (DFS) between 20,0cm and 40,0cm. As that occurs in human medicine, new research strengthens the development and prospects for the use of radiotherapy as a safe option for treating cancer in animals. This paper presents a methodology for calculating the exposure time for superficial radiotherapy procedures in veterinary medicine for small animals (dogs and cats). The dosimetric parameters of X-rays are determined using a spreadsheet tool for Microsoft Office Excel, developed in this paper for a device Dermopan 2, Veterinary Hospital of UNESP in Araçatuba. Using the worksheet helps the veterinarian to determine the time of exposure to radiation determined for each clinical case, optimize the workflow for professionals in veterinary radiotherapy procedures, which often lack the medical physics in team and at the time of radiotherapy. The correct use of spreadsheet decreases the chances of errors in dose rates of radiation, providing a higher quality of care

A energia solar fotovoltaica e seu mercado no Brasil

A energia solar fotovoltaica tem se destacado como uma opção de fonte energética limpa e muito confiável. No entanto, é a Europa que detém a maior representatividade fotovoltaica no mercado mundial, indo contra o senso comum de que seriam os países pertencentes ao Cinturão do Sol aqueles com a maior capacidade instalada. Apesar das condições favoráveis para o desenvolvimento da fonte, o Brasil possui um mercado muito deficitário, contando apenas com poucos projetos de incentivo para levar eletricidade para comunidades carentes afastadas dos centros de geração ou das redes de distribuição. O país carece de programas exclusivos para a energia solar fotovoltaica que proporcionem incentivos ao mercado, a fim de impulsionar a indústria local e estimular o investimento no longo prazo para a maior diversificação da matriz energética brasileira. Assim, o presente estudo buscou ilustrar e analisar o cenário do mercado brasileiro atual da energia solar fotovoltaica, apresentando seus saldos comerciais com os quatro principais mercados mundiais para a fonte: Europa, EUA, Japão e China, segundo os dados disponibilizados pelo banco de dados Aliceweb para os itens 8541401, 8541402 e 8541403, classificados segundo a NCM

Caracterização hidráulica do aspersor Super 10 e sua influência na energia cinética e erosividade

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

A Inserção da astronomia na grade curricular do ensino médio do Estado de São Paulo

We performed in this study an analysis of Curriculum Astronomy contents the public schools of São Paulo from the available educational materials to teachers and students by the state board of education. We analyzed the conditions that teachers carry out the activities suggested to the teaching-learning situations, considering factors such as time available for classes, available material and the general technical condition to perform the activities suggested by the material. Thereafter, we conducted a search with teachers from public of São Paulo, than three cities in the Vale do Paraíba, in order to trace a general framework of the perception of these teachers about the introduction of Astronomy in Physical during the implementation of the new curriculum

Análise dos parâmetros técnicos e econômicos do aquecedor solar a vácuo, visando economia de energia

This work is about a development of a vacuum solar water heater. To accomplish this, some measurements were made, such as flow, water temperature and room temperature, relative humidity, solar power density and wind speed. It first presents a brief explanation about the global situation in relation to the accelerated use of exhaustible energy sources which can result in a breakdown of these for future generations. From this, is proposed to analyze this solar water heater with vacuum tubes during the winter season in Brazil southeastern region, under different environmental conditions. From such ideas became possible to prove through the experimental part, calculations and graphical results that technology and the performance of this device are technical and economically viable, according to the life cycle of this. It was also found that the average monthly production in a maximum heat stroke situation was 193,33kWh and minimum isolation was 57,76kWh. This reveals that this instrument should start to be examined more closely by all, as a way to reduce the use of electricity, which will protect the environment without reducing the comfort of people