Evaporação de gotas de caldas contendo fungicidas e adjuvantes depositadas em superfície

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Modelagem do escoamento transiente ao longo de trocadores de calor tubo capilar-linha de sucção

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Qualidade da carne de suínos submetidos a ambiente controlados e não controlados

Pós-graduação em Zootecnia - FCAV

Comparação entre métodos de dimensionamento de dutos de sistemas de RVAC

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Comparação da viabilidade técnica-econômica em condicionamento de ar: compressor a pistão versus compressor rotativo de velocidade variável

Pós-graduação em Engenharia Mecânica - FEG

Sistema de ar condicionado por absorção para ônibus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Sistemas de resfriamento evaporativo-adsortivo aplicados ao condicionamento de ar

Pós-graduação em Engenharia Mecânica - FEG

Avaliação do efeito da umidade relativa do ar no coeficiente de performance de um sistema de ar condicionado

Os fatores que influenciam no consumo de energia de um sistema de ar condicionado de pequeno porte, que merecem destaque são a eficiência do compressor através do modelo empregado, a forma que a vazão do refrigerante é condicionada, o modelo do ventilador empregado, o rendimento do evaporador, o condensador e as condições climáticas. Dentro da questão climática, uma questão bastante interessante é que a umidade relativa do ar, quando se trata do efeito que ela causa, principalmente no rendimento do condensador a ar, em geral não é considerada nos projetos. Este trabalho tem como objetivo avaliar a influência da umidade relativa do ar no coeficiente de performance do sistema (COP), procurando quantificar sua influência nas respectivas faixas em que elas acontecem. Nos resultados encontrados foi possível identificar que existe uma influência bastante significativa, principalmente quando comparam-se condições de alta umidade com de baixa umidade destacando que somente a partir da 65% de umidade relativa é que encontra-se alterações significativas no COP do sistema

Modelagem e simulação numérica de um sistema de refrigeração por absorção utilizando o par H2O-LiBr

The term refrigeration solar refers to any air conditioning system that uses solar energy as a primary energy source. The use of solar radiation for cooling purposes is divided according to their technological possibilities which are distinguished from one another as the way that energy is involved in the cycle, work or heat. The first case is related to vapor compression cycles, in which the work input is provided by the photovoltaic conversion of solar energy into electrical energy. In the second case, an absorption refrigeration cycle is used and the thermal energy collected from the solar radiation is provided at the generator of this cycle.. In this work a system with an absorption cycle using the pair BrLi-water, using solar energy as input is modeled. It is considered a simple refrigeration cycle whose the equations of mass and energy conservation in each component are developed in order to obtain an algebraic equation set and a simulation routine using the EES software. Although the simulation operates under certain specified thermal load it is possible to estimate the necessary areas of heat exchangers and solar collectors

Avaliação do potencial de microgeração em despacho econômico para atendimento aos requisitos de etiquetagem de edifícios

The discussions about the energy rationalization are gaining more and more space on the everyday of engineers and other professionals in the field of energy. A greater focus is being tied to commercial buildings, because they are one of the biggest responsible for the high energetic expenditure according to the National Energetic Balance, especially by the use of air conditioners for the people’s thermal comfort. Such finding made INMETRO to develop a building labeling procedure through th National Program of Electric Energy Conservation in Buildings; by means of this systematic, the built areas are classified by levels that go from A(the best) to E(the worst), taking into account envelopment, illumination system and air conditioning. A bonus process based on water rationalization, use of renewable energy sources, cogeneration systems or technical innovations, allows the classification to be changed up to one level. A study made exactly on a commercial building, the building of Foundation for Technological and Scientific Development located inside of the College of Engineering of Guaratinguetá, sought to identify technical/economic alternatives for the building certification and appealed to the bonus based on water rationalization. The present study is based on analysis of deploying a cogeneration system formed by internal combustion engine and an absorption refrigeration system as bonus alternative, so that the costs are analyzed regarding energy consumption and use of the motor. With the calculations and results, the viability of the building to receive a bonus from INMETRO through its National Program for Energy Conservation in Buildings is studied and concluded from this study whether or not you can get a better level of energy efficiency for the building in question... (Complete abstract click electronic access below)

Selo PROCEL edifica - edifícios comerciais, de serviços e públicos

This paper presents a study on the labeling Procel Build, an action plan for energy efficiency in buildings which aims to build the foundations necessary to rationalize energy consumption in buildings in Brazil (PROCEL, 2009a, p. 5), ie Procel builds aims to ensure the construction of the building that has a low energy expenditure, but still provide a comfortable environment. In this research, it is also shown how the labels are obtained, which may be general or partial. The reader will find further explanation of the three aspects of a building, and they Envelopment, Lighting system and Air Conditioning System Finally, we present the advantages and challenges of system builds procel, showing the need for greater investment and disclosure of elements that contribute to the implementation of sustainable buildings in Brazil

Estudo de cargas térmicas de uma aeronave e dimensionamento de um sistema de ar condicionado

This work deals with the thermal load study of a fictitious aircraft as well as scaling, in terms of the airflow and temperature of the air conditioning system, for heating and cooling of the its internal environment, aiming the thermal comfort of occupants. The first part is presented the techniques and methods utilized for modeling different heat exchanges that occur in the aircraft and then allowed to calculate the total heat load and the airflow and temperature necessary to comply with the requirements of the thermal comfort. Techniques to determine the basic parameters, as convection coefficient and global coefficient of heat exchange, are also presented. The work aims to develop a program, using a computational tool, to automate the calculations so that facilitate this study. It also allows to be used for other airplanes just changing parameters and the control variables related to the specific project. Finally the program performs calculations for a fictitious airplane, to analyze its functionality and the influence of parameters involved in the temperature controls. The program allowed analyzing the sensitivity of portions of the thermal load and the corresponding parameters of influence, as well as the scaling of the air conditioning in terms of airflow and temperature. It was considered, despite the simplifications, a good approximation to the actual values and then can be used in development of the other airplanes

Eficiência energética em ar condicionado e refrigeração através da aplicação da termoacumulação

The use of refrigeration and air conditioning systems is of fundamental importance when it comes to air-conditioning of environments. Also important is the use of electricity for equipments’ operation related to these systems. Due to high cost of charging for this type of energy, factors economy and efficiency occupy key roles among design parameters of a system. One of the ways to get this economy is the use of a technique called thermal storage, or cold storage, which intends to move the required loads during peak time and also their equalizing, so that the energy is transferred from the peak time to non-peak time, thereby reducing the cost of energy consumed. Cold can be stored in the form of ice or ice water. This work aims to perform a technical-economic analysis of a mall located in Vale do Paraíba checking the feasibility of deploying a thermal storage system to achieve an economy in the cost of the energy used by the establishment. Through the parameters measured by the concessionaire of energy we can get the values of energy demand and power consumed, which will serve as basis for calculation for the study. The results obtained allow the development of two alternative proposals to the current configuration, one chosen by the criteria and results presented by technical-economic and energy analysis

Proposta de metodologia para aplicação de eficiência energética em uma usina hidrelétrica

Pós-graduação em Engenharia Mecânica - FEG

Lattices from subfields of Q (xi n)

In this paper we present a method for evaluating the center density of algebraic lattices from subfields of Q(xi n), where n is a positive integer. This method allows to reproduce rotated versions of dense lattices in some dimensions. Constellations on algebraic lattices with high packing density have been proposed for use in communications in Gaussian channels and also in Rayleigh fading channels in case they have high diversity.