Immersion heaters are used by industries to heat fluids. The element of an immersion heater need to be fully immersed into the heated liquid, otherwise it could be subject to overheat. The main purpose of this thesis is to find a temperature sensor, which could signal in case the immersion heater is at risk to suffer from overheat due to low liquid level. A comparison of accuracy, size and cost between an analog and a digital sensor is held, to conclude whether either one is at an advantage for this application.An immersion heater with ceramic element and quartz glass tube and a water tank, both provided by Scandymet, is used during experiments. First, the position for the sensor inside the heater was examined, by placing the sensor at different positions. Next, measurements of the operating temperature of the immersion heater were made at different liquid levels. This resulted in a placement for the sensor near the head of the immersion heater and an approximate temperature range from 41 ℃ to 58 ℃. Both the analog and digital sensors is chosen with measurable ranges to match the result from previous experiments. A thermistor along with a linearizing series resistor make the analog design and a DS18B20+ with a pull-up resistor the digital design. The microcontroller for both designs is Adafruit Feather Adalogger M0, which is programmed in C/C++ using Arduino IDE software. It is concluded that it is possible to signal in case liquid level decrease below minimum level, by inserting a temperature sensing device into the immersion heater. The sensor should be placed above the maximum liquid level mark, close to the head of the heater. The analog design would be recommended as overheat protection, due to its smaller size, less expensive and, with further calibration, accurate response.

Made available in DSpace on 2015-03-26T13:28:01Z (GMT). No. of bitstreams: 1 texto completo.pdf: 5717096 bytes, checksum: fac70b2c7ad0d5d10768b79aa66a218f (MD5) Previous issue date: 2011-02-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this paper we propose a research about the implementation of the system of solar water heating systems in social housing, from the point of view of sustainability of technology adopted. Sustainability is understood in a broad sense, involving among others, the economic, social, environmental and cultural as well as the habits and customs rooted in the resident population. Just a few examples of practical application and little literature on the deployment of technologies for energy savings in social housing, especially from the standpoint of sustainability and adaptation of the population to new technologies. To this end, we seek to identify the impacts generated by the insertion of solar collectors in social housing, produced by MG-COHAB (Housing Company of Minas Gerais) Homes Program - Housing in small towns in Minas demographic General, assessing the appropriateness of incorporating solar collectors to the habits and customs of the population and possible changes in behavior resulting from the presence of this new technology into living space. We conducted three case studies, the Homes of Mercy of Caratinga, Itatiaiuçu and Dores de Campos. It was conducted in each housing a Post-Occupancy Evaluation Behavior gauge user satisfaction with respect to the installation of solar water heaters in homes. As main results we have: user satisfaction with the financial savings generated by the solar heater and the comfort afforded by the increase of the length of the shower, due to carelessness in terms of energy consumption, lack of regular maintenance of the system solar heating by the residents, the discrepancy between the use of solar heating and reduced environmental impacts. We conclude that despite the positive impacts related to economic and cultural sustainability, residents do not relate to use of solar technology with sustainability and therefore the incorporation of solar collectors is not sufficient to create an environmental awareness. These results show that the act of incorporation of the solar heater in social housing by COHAB-MG represents important social gains, but must be accompanied by an awareness campaign in order to extend the benefits to the population, characterized as an important step towards a balanced social housing, for sustainability. / Neste trabalho propõe-se uma investigação acerca da implantação do sistema de aquecimento solar de água na habitação de interesse social, sob o ponto de vista da sustentabilidade da tecnologia adotada. Entende-se a sustentabilidade num sentido amplo, que envolve entre outros, os aspectos econômicos, sociais, ambientais e culturais bem como os hábitos e costumes arraigados na população residente. Ainda há poucos exemplos de aplicação prática e pouca literatura sobre a implantação de tecnologias visando à economia de energia na habitação de interesse social, sobretudo sob o ponto de vista da sustentabilidade e da adaptação da população às novas tecnologias utilizadas. Para tanto, busca-se identificar os impactos gerados com a inserção de coletores solares na habitação de interesse social, produzida pela COHAB-MG (Companhia de Habitação de Minas Gerais) no Programa Lares - Habitação Popular, em cidades de pequeno porte demográfico em Minas Gerais, avaliando a adequação da incorporação dos coletores solares aos hábitos e costumes da população e possíveis mudanças de comportamento decorrentes da presença dessa nova tecnologia no espaço habitacional. Foram realizados três estudos de caso, nos conjuntos habitacionais de Piedade de Caratinga, Itatiaiuçu e Dores de Campos. Efetuou-se em cada conjunto habitacional uma Avaliação Pós- Ocupação Comportamental para aferir a satisfação dos usuários com relação à instalação do aquecedor solar nas habitações. Como principais resultados encontrados têm-se: a satisfação dos usuários com a economia financeira gerada pelo aquecedor solar e com o conforto propiciado pelo aumento do tempo de uso do chuveiro, decorrente da despreocupação em relação ao consumo energético; a falta de manutenção periódica do sistema de aquecimento solar pelos moradores; a desvinculação entre o uso do aquecimento solar e a redução dos impactos ambientais. Conclui-se que, apesar dos impactos positivos relacionados com a sustentabilidade econômica e cultural, os moradores não relacionam a utilização da tecnologia solar com a sustentabilidade e, portanto, a incorporação dos coletores solares não é suficiente para criar uma consciência ambiental. Esses resultados mostram que a ação de incorporação do aquecedor solar na habitação de interesse social pela COHAB-MG representa importantes ganhos sociais, mas deve ser acompanhada de um trabalho de conscientização com a finalidade de ampliar os benefícios concedidos à população, caracterizando-se assim como um importante passo na busca de uma habitação social equilibrada, em prol da sustentabilidade.

Orientador: Carlos Alberto Mariotoni / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-11T03:43:35Z (GMT). No. of bitstreams: 1 GaticaRispoli_ItaloAlberto_D.pdf: 6435454 bytes, checksum: 44d0ad6b7c73d5524af7689e79c72fd8 (MD5) Previous issue date: 2008 / Resumo: Esta pesquisa representa uma contribuição à área de recursos hídricos, energéticos e ambientais, buscando prover subsídio técnico ao planejamento energético pelo lado da demanda, atuando favoravelmente na estabilidade dos sistemas elétricos convencionais. Estudou-se a redução do custo fabril de um aquecedor solar de linha industrializada, que apresente adequado desempenho na estação fria do ano. Para isto, foi necessário revisar o tema da irradiação solar e paralelamente ensaiar protótipos e materiais. O resultado final desta pesquisa reúne subsídios aos estudantes de engenharia civil, ambiental, arquitetura, projetistas, fabricantes e vendedores da tecnologia termo solar. Ainda foi possível modelar uma linha sustentável de financiamento para a classe média brasileira sem prejuízo do banco credor. Palavras-chave: irradiação solar, energia limpa, sustentabilidade, aquecedor solar, transfer~ncia de tecnologia, tecnologia apropriada / Abstract: This research represents a contribution to the hydric resources, energetics and environmental, serving as a technical aid to the energetical planning per the demand side, acting favorably on the stability of the conventional electrical systems. It has been studied a reduction on the manufacturing cost of an industrialized solar heater that performs well during the cold season of the year, being necessary to review the solar radiation subject and at the same time test. prototypes and materiais. The final result of this research gathers aid to civil, environmental engineering students, as well to architecture students, designers, thermo solar technology makers and salespeople. It was still possible to model a sustainable credit line for the Brazilian middle class, with no loss to the bank. Key words: solar radiation, clean energy, sustainability, solar heater, technology transference, appropriated technology / Doutorado / Recursos Hidricos, Energeticos e Ambientais / Doutor em Engenharia Civil

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A âCombustÃo de FiltraÃÃoâ à uma tecnologia que tem sido empregada no desenvolvimento de aquecedores e caldeiras de alta eficiÃncia e baixa emissÃo de poluentes. No entanto, o processo de igniÃÃo da combustÃo nesses equipamentos, constituÃdos de queimadores porosos volumÃtricos, tem sido ainda uma questÃo nÃo resolvida. Os sistemas convencionais desenvolvidos para esses queimadores apresentam algum inconveniente operacional que prejudica a eficiÃncia de combustÃo. EntÃo, este trabalho tem como objetivo principal apresentar um projeto robusto e econÃmico de sistema de igniÃÃo por lanÃa-chamas destinado a queimadores porosos volumÃtricos, em que a CombustÃo de FiltraÃÃo està sendo aplicada como tecnologia de base para desenvolvimento de um novo modelo de aquecedor de Ãgua. Um protÃtipo do aquecedor equipado com o sistema de igniÃÃo foi desenvolvido, em escala de laboratÃrio, realizando-se estudos experimental e teÃrico quanto à queima com gÃs natural e com biogÃs. A anÃlise teÃrica envolve a caracterizaÃÃo do escoamento dos gases ao longo do corpo do sistema de igniÃÃo atravÃs da simulaÃÃo com o software âANSYS-CFXâ, como tambÃm, dos fenÃmenos relacionados à onda de combustÃo propagando-se no queimador do aquecedor, para o qual foi utilizado um modelo numÃrico de simulaÃÃo em FORTRAN. Neste contexto, à utilizado o software PREMIX no cÃlculo de equilÃbrio quÃmico, aplicÃvel à combustÃo prÃ-misturada em um meio poroso, tomando como referÃncia os dois parÃmetros principais de operaÃÃo: a razÃo de equivalÃncia e a velocidade do escoamento da mistura ar-combustÃvel. Como resultado: o sistema de igniÃÃo proposto mostrou-se adequado aos queimadores porosos, provendo estabilidade e facilidade de operaÃÃo, e reduzindo significativamente o tempo necessÃrio ao prÃ-aquecimento do meio poroso. O modelamento do escoamento e da combustÃo serviu de suporte para interpretaÃÃo adequada dos fenÃmenos presentes nos processos. A CombustÃo de FiltraÃÃo possibilitou a operaÃÃo estÃvel do aquecedor em ampla faixa de razÃo de equivalÃncia (de 0.30 a 1). / "Filtration Combustion" is a technology that has been used in the development of heaters and boilers with high efficiency and low pollutant emissions. However, the ignition process of combustion in such equipments, constituted of volumetric porous burners, have been an issue still unresolved. Conventional systems developed for these burners present some operational drawback that affects the combustion efficiency. So, this work aims mainly to present a robust and economical design of flame-thrower ignition system aimed at volumetric porous burners, in which Filtration Combustion is being applied as a basis technology for the developing a new model of water heater. A prototype of the heater equipped with the ignition system has been developed in laboratory scale, carrying out experimental and theoretical studies on the burning natural gas and biogas. The theoretical analysis involves the characterization of gas flow along the body of the ignition system through simulation with the software "ANSYS-CFX," as well as of the phenomena related to the combustion wave propagating itself through the heaterâs burner, for which a numerical simulation in FORTRAN has been used. In this context, a software âPREMIXâ was used in the chemical equilibrium calculation, applicable to premixed combustion in a porous medium, taking as reference the two main parameters of operation: the equivalence ratio and flow velocity of the air-fuel mixture. As a result, the ignition system proposed has been adequate to the porous burner, providing stability and ease of operation, and significantly reducing the time required for preheating the porous medium. The modeling of flow and combustion has served as a support for proper interpretation of the phenomena present in the processes. Filtration Combustion has allowed stable operation of the heater in a wide range of equivalence ratio (from 0.30 to 1).

This research investigates the use of an alternate means of modelling the performance of a train of feed water heaters in a steam cycle power plant, using machine learning. The goal of this study was to use a simple artificial neural network (ANN) to predict the behaviour of the plant system, specifically the inlet bled steam (BS) mass flow rate and the outlet water temperature of each feedwater heater. The output of the model was validated through the use of a thermofluid engineering model built for the same plant. Another goal was to assess the ability of both the thermofluid model and ANN model to predict plant behaviour under out of normal operating circumstances. The thermofluid engineering model was built on FLOWNEX® SE using existing custom components for the various heat exchangers. The model was then tuned to current plant conditions by catering for plant degradation and maintenance effects. The artificial neural network was of a multi-layer perceptron (MLP) type, using the rectified linear unit (ReLU) activation function, mean squared error (MSE) loss function and adaptive moments (Adam) optimiser. It was constructed using Python programming language. The ANN model was trained using the same data as the FLOWNEX® SE model. Multiple architectures were tested resulting in the optimum model having two layers, 200 nodes or neurons in each layer with a batch size of 500, running over 100 epochs. This configuration attained a training accuracy of 0.9975 and validation accuracy of 0.9975. When used on a test set and to predict plant performance, it achieved a MSE of 0.23 and 0.45 respectively. Under normal operating conditions (six cases tested) the ANN model performed better than the FLOWNEX® SE model when compared to actual plant behaviour. Under out of normal conditions (four cases tested), the FLOWNEX SE® model performed better than the ANN. It is evident that the ANN model was unable to capture the “physics” of a heat exchanger or the feed heating process as a result of its poor performance in the out of normal scenarios. Further tuning by way of alternate activation functions and regularisation techniques had little effect on the ANN model performance. The ANN model was able to accurately predict an out of normal case only when it was trained to do so. This was achieved by augmenting the original training data with the inputs and results from the FLOWNEX SE® model for the same case. The conclusion drawn from this study is that this type of simple ANN model is able to predict plant performance so long as it is trained for it. The validity of the prediction is highly dependent on the integrity of the training data. Operating outside the range which the model was trained for will result in inaccurate predictions. It is recommended that out of normal scenarios commonly experienced by the plant be synthesised by engineering modelling tools like FLOWNEX® SE to augment the historic plant data. This provides a wider spectrum of training data enabling more generalised and accurate predictions from the ANN model.

This thesis deals with design of hot water grate boiler, where the output is water with parameters 130 °C and pressure 16 bar. In the content of the whole thesis is gradually introduced a stoichiometric calculations, which is based on the specified fuel – wood chips. This is followed by the design of the individual heating surfaces according to the thermal calculations given in the thesis. Finally, the calculation is extended by hydraulic and aerodynamic losses. Dimensional design, as a basic scheme, is shown at thesis. More detailed drawing documentation is attached to this thesis.

This thesis deals with issue of grate boilers. It describes their properties, function principles and usage. The main part of this thesis is design of grate boiler burning biomass with steam output 96.4 tons/hour. Steam temperature and pressure at the output are 490 °C and 8.1 MPa.

The work generally deals with the possibilities of preparing hot water in household and analyzes saving posibilities. At the beginning of work the history of hot water preparation is briefly indicated. Chapter 3 deals with different ways of heating. Described in more detail electric storage heating is in chapter 4, where can be found the effect of heating to the power network, especially to the daily load diagram. The following are the information of the tariff policy, as a tool for motivation of consumers, for using the storage heating. In the next part, beginning with the fifth chapter, is written about the possibility of energy saving by means of intelligently controlled boiler. That eliminates the disadvantage of storage heating, which are the tank thermal losses. Heating is based on a certain regularity in the behaviour of the user and manages the preparation of water according to expected consumption. The sixth chapter then contains design of own algorithm for economical control of heating and also energetic and economic assessment of potential savings.

The goal of this diploma thesis is suggest solution of ventilation and heating of industrial building. The solution is primarily based on calculation of thermal losses and thermal gains of the building. The project deals with supply of air for individual parts of construction in summer and winter. The solution consist of proposal of ducting and calculation of air handling units and unit heaters. The system of ventilation and heating is process in drawing documentation.

This diploma thesis describes the detailed design of heating and hot water heating for a family quest-house. At first the reader is introduced to the designed building, its design and construction elements. The thesis presents the calculation procedure and design of the heating system. This consists of designing radiators, the heat source, the circulating pumps, regulations of the heating system and the design of its security elements. The thesis also describes the design of the heat exchanger for hot water and security. In conclusion, an evaluation of operating costs with the recommended solution for their reduction. The thesis also includes drawing documentation of structural drawings, heating and unrolled schema that is mentioned in the attachment.