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REFRIGERATOR COMPRESSOR TREATMENT AND RECYCLINGKATTA, KRANTHI KUMAR, Okogwu, Ifeanyi William January 2020 (has links)
Social demands of recycle is becoming strong. In modern production systems, largenumber of one model of product is manufactured at a time and the way ofproduction operations are well specified. In recycling systems, on the contrary, it isusual that operation of disassemble for each works differs. Because of this,achieving high efficiency in recycling systems have been difficult. Quality FunctionDeployment (QFD) was implemented in the project to obtain clear understandingof the problem being dealt with. Being a case study in the recycling of end-of-liferefrigerators means there are several stakeholders which must be satisfied includinggovernment regulations, workforce, and the business organisation. At the same timeproductivity is maximised while cost and time is diminished. Designing withfunction, brainstorming and patent searches were used to generate new ideas.Building morphology was also used to generate ideas as well as document them.The results of the project are different concepts that can be applied individually anda comprehensive concept that will entail exhaustive change in the entire system.The recycling of compressors for material recovery is discussed. / http://www.diva-portal.se/smash/get/diva2:1326957/FULLTEXT02.pdf
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Automation of coolant agent extraction in refrigeratorsOsberg, Jacob, Islam, Nurul January 2019 (has links)
Refrigerators contains something called CFC which is a gas that depletes the ozone layer if it is not handled correctly. The recycling of refrigerators has therefore a lot of regulations surrounding it, making it extremely important to have full control over the recycling process. The pre- treatment process of refrigerator recycling is today a fully manual process. This introduces high amounts of physical strain on the employees, especially in the compressor removal stage. This project focused therefor on developing conceptual ideas for automating or semi-automating the pre-treatment process at the Stena Nordic Recycling Hub in Halmstad, Sweden. Since there are no automated pre-treatment manufacturing lines in the recycling industry today regarding refrigerators, a theoretical review on related areas was done. Visits to the plant were made and employees were interviewed about the current process. In the end two concepts were presented as suitable ideas for automating the process to an extent that removes the major physical strain of the production line but still contains the control of the process. One concept for the stage of removing the compressor and one concept for the production line as a whole. The compressor removal concept utilizes an articulated robot equipped with a claw that is controlled by an image analysis system.
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Desenvolvimento de metodologia de eficiência energética para aplicação em processos industriais de laticínios /Silva, Natalia Faria. January 2016 (has links)
Orientador: Pedro Magalhães Sobrinho / Coorientador: José Luz Silveira / Banca: Júlio Santana Antunes / Banca: Lucia Bollini Braga / Resumo: Neste trabalho é proposto um modelo metodológico que permite melhorar o desempenho energético através da implementação de medidas de eficiência energética. O modelo é fundamentado em quatro níveis de atuação e foi desenvolvido mediante uma revisão do estado da arte no Brasil e no mundo de aspectos referentes a eficiência energética. A estrutura da metodologia, denominada pirâmide de conservação de energia, foi desenvolvida sob o conceito de melhoria contínua e está baseado nas melhores práticas para alcançar a excelência energética adotado em países desenvolvidos como Estados Unidos, Canadá e Alemanha. Um estudo de caso em uma indústria de laticínio foi realizado para mostrar a aplicabilidade e eficácia do método proposto. O estudo detalhou as diversas possibilidades para reduzir as irreversibilidades dos sistemas energéticos dessa indústria e apresentou propostas técnicas e economicamente viáveis de melhoria da eficiência no uso da energia. Os resultados apresentados mostram que a adoção de medidas de eficiência energética reduz os custos, melhora as condições operacionais e tem impacto positivamente sobre o meio ambiente / Abstract: This work proposes a methodological model which improves the energy performance by implementing energy efficiency measures. The model is based on four levels of action and was developed through a review of the state of the art in Brazil and in the world of aspects related to energy efficiency. The structure of the methodology, called energy conservation pyramid was developed under the concept of continuous improvement and is based on best practices to achieve energy excellence adopted in developed countries like United States, Canada and Germany. A case study in a dairy industry was carried out to show the applicability and effectiveness of the proposed method. The study detailed the various possibilities to reduce the irreversibility of energy systems of the industry and presented technical proposals and costeffective improvement of efficiency in energy use. The results presented show that the adoption of energy efficiency measures reduce costs, improve operating conditions and impacts positively on the environment / Mestre
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Analysis of conjugate heat transfer in tube-in-block heat exchangers for some engineering applicationsGari, Abdullatif Abdulhadi 01 June 2006 (has links)
This project studied the effect of different parameters on the conjugate heat transfer in tube-in-block heat exchangers for various engineering applications. These included magnetic coolers (or heaters) associated with a magnetic refrigeration system, high heat flux coolers for electronic equipment, and hydronic snow melting system embedded in concrete slabs. The results of this research will help in designing the cooling/heating systems and select their appropriate geometrical dimensions and material for specific applications. Types of problems studied in this project are: steady state circular microchannels with heat source in the gadolinium substrate, transient heat transfer in circular microchannels with time varying heat source in a gadolinium substrate, transient heat transfer in composite trapezoidal microchannels of silicon and gadolinium with constant and time varying heat source, steady state heat transfer in microchannels using fluids suspended with nanoparticl
es, and analysis of steady state and transient heat transfer in a hydronic snow melting system. For each of these problems a numerical simulation model was developed. The mass, momentum, and energy conservation equations were solved in the fluid region and energy conservation in the solid region of the heat exchanger to arrive at the velocity and temperature distributions. Detailed parametric study was carried out for each problem. Parameters were Reynolds number, heat source value, channel diameter or channel height, solid materials and working fluids. Results are presented in terms of solid-fluid interface temperature, heat flow rate, heat transfer coefficient, and Nusselt number along the length of the channel and with the progression of time. The results showed that an increase in Reynolds number decreases the interface temperature but increases the heat flow rate and Nusselt number. When the heat source varied with time, by applying and removing the magnetic field, the interface
temperature, heat flow rate, and Nusselt number attained a periodic variation with time. The decrease in the diameter at constant Reynolds number decreases the interface temperature and increases the heat flow rate at the fluid-solid interface.
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Ocorrência de cisticercose bovina em frigorífico localizado na zona da mata mineira / Occurrence of bovine cysticercosis in refrigerator located in the mining area killsGomes, Marco Antônio Ritter Bastos 27 January 2014 (has links)
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Previous issue date: 2014-01-27 / This work was conducted on the basis of data collection through the Federal inspection service (S.I.F) of the Ministry of Agriculture, Livestock and Food Supply (MAPA) in a refrigerator located in the Zona of Mata of Minas Gerais, with a capacity of 100 daily slaughter bovine animals, on average, in the period from 2007 to 2012 as the presence of cysticercosis. It was adopted the post-mortem examination as method of diagnosis according to the standards advocated by the S.I.F (BRAZIL, 1971, 1980, 1988, 2006). It was aimed to register the occurrence of cysticercosis in bovine animals examined in the routine inspection. It may be noted that in the biennium 2008-2009, recorded-if an increase in the relative risk at 22% for cysticercosis and in 2009-2010 was an increase of 14% of this parasitosis. From 2010, a 50% reduction in the relative risk and the 2011- 2012 biennium a 59% risk reduction. When analysing the period of 2007 to 2012, there has been an 80% reduction in relative risk of cysticercosis. Tuberculosis is a zoonosis of great impact in terms of public health, as well as cysticercosis, performed analogously to the same, an increase of 4.98 percent to 10.37% from 2007 to 2008, and even in the last year, had an prevalence (1.47%) above the national average (1.3%), according to data from Brazil, 2006. Despite the fall of cysticercosis from the year 2010, this zoonosis should not be disregarded by public agencies and consumers. / Este trabalho foi conduzido com base em levantamento de dados por meio do Serviço de Inspeção Federal (S.I.F), do Ministério da Agricultura, Pecuária e Abastecimento (MAPA) em frigorífico localizado na zona da mata mineira, com capacidade de matança diária de 100 bovinos, em média, no período de 2007 a 2012 quanto a presença de cisticercose. Foi adotado o exame post-mortem como método de diagnóstico de acordo com as normas preconizadas pelo S.I.F (BRASIL, 1971, 1980, 1988, 2006). Objetivou-se registrar a ocorrência de cisticercose em bovinos examinados na rotina de inspeção. Pode-se notar que no biênio 2008-2009, rigistrou-se um aumento do risco relativo em 22% para a cisticercose e em 2009-2010 ocorreu um aumento de 14% desta parasitose. A partir de 2010, observou-se uma redução de 50% no risco relativo e no biênio 2011- 2012 uma redução do risco de 59%. Ao analisar o período de 2007 a 2012, verificou-se uma redução de 80% no risco relativo da cisticercose. A tuberculose por ser uma zoonose de grande impacto em termos de saúde pública, assim como a cisticercose, apresentou de forma análoga, um aumento de 4,98% para 10,37% de 2007 para 2008, sendo que inclusive neste último ano, teve uma prevalência (1,47%) acima da média nacional (1,3%), segundo dados de BRASIL, 2006. Apesar da queda de cisticercose a partir do ano de 2010, esta zoonose não deve ser desconsiderada pelos órgãos públicos e pelos consumidores.
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Estudo experimental de um dispositivo de condensação evaporativa, aplicado a refrigeradores domesticos / Experimental study of an evaporative condensation device applied in a domestic refrigeradorChávez Gutiérrez, Mirko Salomon, 1978- 15 August 2018 (has links)
Orientador: Vivaldo Silveira Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-15T20:10:11Z (GMT). No. of bitstreams: 1
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Previous issue date: 2010 / Resumo: Os equipamentos utilizados para refrigeração e condicionamento ambiental têm um potencial significativo de redução de consumo energético, principalmente porque esta pratica utilizam quantidades significativas de energia e são encontrados em todas as residências e indústrias. Neste contexto existem numerosos estudos dirigidos para aumentar a eficiência energética dos sistemas de refrigeração domésticos, utilizando diferentes estratégias tecnológicas. O dispositivo proposto neste trabalho atua como um condensador evaporativo, substituindo o ar,, como meio de troca térmica convencional dos sistemas de refrigeração domésticos, por uma corrente vertical de água em contato com a superfície do condensador, aproveitando desta maneira o calor absorvido pela água na mudança de fase (efeito evaporativo) e diminuindo a temperatura de condensação. O protótipo foi desenvolvido, considerando o principio de funcionamento dos condensadores evaporativos industriais e adaptado numa escala menor, para que possa ser facilmente montado na estrutura de um refrigerador doméstico convencional. Com as mudanças nas condições de condensação, especificamente a temperatura, procura-se aumentar o COP (coeficiente de desempenho) que é um indicador da eficiência do sistema, dado que nessas condições de funcionamento, o efeito frigorífico torna-se maior e o trabalho do compressor torna-se menor durante o ciclo. Estas condições de funcionamento, assim como o consumo de energia elétrica, foram monitorados e comparados com os sistemas de refrigeração convencional, utilizando uma câmara especialmente condicionada para esse propósito. Assim, o desempenho do sistema com as novas condições de condensação, promovidas pelo dispositivo, teve uma maior eficiência global com um COP maior em 24% e, em consequência, um aumento da eficiência energética do sistema, com uma redução de 17% de energia em ensaios padronizados conforme norma ABNT 12888 / Abstract: Los equipos utilizados para refrigeración y condicionamiento ambiental tienen gran potencial de reducción de consumo energético, principalmente porque estos aparatos utilizan cantidades significativas de energía y son encontrados en la mayoría de residencias y en las industrias. Existen numerosos estudios dedicados a aumentar la eficiencia energética de los sistemas de refrigeración domésticos utilizando diferentes estrategias tecnológicas. El dispositivo propuesto en este trabajo actuara como un condensador evaporativo, substituyendo el aire, como medio de intercambio de calor convencional de los sistemas de refrigeración domésticos, por una corriente vertical de agua en contacto con la superficie del condensador, aprovechando de esta forma el calor absorbido por el agua durante el cambio de estado (efecto evaporativo) y disminuyendo la temperatura de condensación. Este prototipo fue desarrollado considerando el principio de funcionamiento de los condensadores evaporativos industriales y fue adaptado a una escala menor, para que pueda ser fácilmente instalado en la estructura de un refrigerador domestico convencional. Con las modificaciones en las condiciones de condensación específicamente, la temperatura, se procura aumentar el COP (coeficiente de desempeño), que es un indicador de la eficiencia del sistema, en vista que en estas condiciones de funcionamiento, el efecto frigorífico se torna mayor y el compresor trabaja menos durante el ciclo. Estas condiciones de funcionamiento, así como el consumo de energía eléctrica son monitoreados e comparados con los sistemas de refrigeración convencional, utilizando una cámara especialmente condicionada para este propósito. De esta manera el desempeño del sistema con las nuevas condiciones de condensación, promovidas por el dispositivo en estudio, tuvo una mayor eficiencia global con un COP superior en 24%, y como consecuencia un aumento de la eficiencia energética del sistema, con una reducción del consumo de energía en 17% durante ensayos homogenizados según la norma Brasileña ABNT 12888 / Mestrado / Mestre em Engenharia de Alimentos
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Performance Analysis Of A Photovoltaic Powered Cold StoreKandhway, Vikash 02 1900 (has links) (PDF)
No description available.
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Gerenciamento de refrigeradores para redução do pico de demanda em redes inteligentes / Smart management of refrigerators for peak load reductionNiro, Glauco 18 August 2018 (has links)
Orientador: Luiz Carlos Pereira da Silva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-18T12:45:34Z (GMT). No. of bitstreams: 1
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Previous issue date: 2011 / Resumo: Os sistemas elétricos vêm sendo alvo de estudos que buscam torná-los mais inteligentes e seguros. Um novo paradigma surge com o conceito das redes inteligentes (smart grids), as quais incluem como uma das suas características principais a integração de equipamentos dos consumidores de forma ativa à operação do sistema elétrico. Um exemplo é o gerenciamento da demanda no horário de pico, aliviando a carga e aumentando a segurança do sistema, com o objetivo de obter benefícios para o sistema elétrico e também para os consumidores. Para que isso seja possível, são necessários alguns requisitos e avanços tecnológicos: existência de um portal de comunicação para interface entre o consumidor e seus aparelhos e a concessionária; equipamentos que permitam tal gerenciamento sem prejudicar e interferir na rotina dos consumidores; e mecanismos de compensação financeira para incentivar a participação dos consumidores. Nesta dissertação se propõe um estudo sobre um aparelho que apresenta potencial para esse tipo de gerenciamento, o refrigerador doméstico. Devido a sua inércia térmica e isolamento o refrigerador pode ser ligado e desligado durante algum tempo sem prejuízos para sua função principal. Os objetivos deste trabalho são: desenvolver um modelo adequado para a simulação computacional de um grupo de refrigeradores; implementar esquemas de gerenciamento que visem a redução de consumo no horário de pico; bem como analisar o efeito que estes procedimentos acarretariam em uma rede de distribuição de energia elétrica, levando em conta a redução do consumo no período de pico, a redução de perdas e a melhoria do perfil de tensão / Abstract: The electrical systems have been exposed to new researches and developments with the main objectives of a smarter and safer operation and planning. A new paradigm arises with the concept of smart grids, which include as one of its main characteristics the integration of consumer's appliances in the system operation in a more active way. An example is the demand-side management at peak time, relieving the load and increasing system security, in order to obtain benefits to the electrical system and also to consumers. In order to make this possible, some requirements and technological advances are necessary: the existence of a communication interface between the consumers and their appliances and the utility; smart appliances that allow such management without any damage or interference on the routine of the consumer; compensation mechanisms to encourage consumer participation. In this dissertation it is proposed a study about a device that has potential to this kind of management, the household refrigerator. Due to its thermal inertia and isolation, the refrigerator can be turned on and off for some time without degradation of its primary function. The objectives of this work are: development of an adequate model for the computational simulation of a group of refrigerators; implementation of management schemes to reduce the consumption at peak time; analysis of the impacts of such procedures to a distribution grid, taking into consideration the reduction of the consumption at the peak hours, reduction of losses and improvement on voltage profile / Mestrado / Energia Eletrica / Mestre em Engenharia Elétrica
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Refrigeration Insulation Using Phase Change Material Incorporated Polyurethane Foam for Energy SavingsShaik, Sania 08 1900 (has links)
Incorporating insulation material with phase change materials (PCMs) could help enhance the insulation capability for a refrigerator system. The phase change material can absorb or release large amount of latent heat of fusion depending on surrounding temperatures for efficient thermal management. This research focuses on how incorporating PCM to the conventional PU foam insulation affects the inside temperatures of the refrigerator system and in-turn helps in conserving energy by reducing the compressor run time. It was found that only 0.25-inch-thick PCM layer in insulation can certainly benefit the refrigerators by reducing the amount of electricity consumption and thus increasing the total energy savings through the numerical study results via COMSOL Multiphysics in this study. This work aims to investigate a PCM-incorporated insulation material to accomplish the enhancement of thermal insulation performance for refrigerators.
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CFD Studies Of Pulse Tube RefrigeratorsAshwin, T R 12 1900 (has links) (PDF)
The performance evaluation and parametric studies of an Inertance Tube Pulse Tube Refrigerator (IPTR) are performed for different length-to-diameter ratios, with the Computational Fluid Dynamics (CFD) package FLUENT. The integrated model consists of individual models of the components, namely, the compressor, compressor cooler, regenerator, cold heat exchanger, pulse tube, warm heat exchanger, inertance tube and the reservoir. The formulation consists of the governing equations expressing the conservation of mass, momentum and energy with axi-symmetry assumption and relations for the variable thermophysical properties of the working medium and the regenerator matrix, and friction factor and heat transfer coefficients in oscillatory flows. The local thermal non-equilibrium of the gas and the matrix is taken into account for the modeling of heat exchangers and the regenerator which are treated as porous zones. In addition, the wall thickness of the components is also accounted for. Dynamic meshing is used to model the compressor zone. The heat interaction between pulse tube wall and the oscillating gas, leading to surface heat pumping, is quantified. The axial heat conduction is found to reduce the overall performance. The thermal non-equilibrium results in a higher cold heat exchanger temperature due to inefficiencies. The dynamic characteristics of pulse tube are analyzed by introducing a time constant. The study is extended to other types of PTRs, namely, the Orifice type Pulse Tube Refrigerator (OPTR), Double Inlet type Pulse Tube Refrigerator (DIPTR) and a PTR with parallel combination of inertance tube and orifice (OIPTR). The focus of the second phase of analysis is the pulse tube region. The oscillatory flow and temperature fields in an open-ended pipe driven by a time-wise sinusoidally varying pressure at one end and subjected to an ambient-to-cryogenic temperature difference across the ends, is numerically studied both with and without the inclusion of buoyancy effects. Conjugate effects arising out of the interaction of oscillatory flow with heat conduction in the pipe wall are taken into account by considering a finite thickness wall with an insulated exterior surface. Parametric studies are conducted with frequencies in the range 5-15 Hz for an end-to-end temperature difference of 200 K. As the pressure amplitude increases, the temperature difference between the wall and the fluid decreases due to mixing at the cold end. The pressure amplitude and the frequency have negligible effect on the time averaged Nusselt number. The effect of buoyancy is studied for hot side up and cold side up configurations. It is found that the time averaged Nusselt number does not change significantly with orientation or Rayleigh number. Sharp changes in Nusselt number and velocity profiles and an increase in energy transfer through solid and gas were observed when natural convection comes into play with hot end placed down. Cooldown experiments are conducted on a preliminary experimental setup. Comparison of the numerical and experimental cooldown curves disclosed a number of areas where improvement is required, primarily the leakage past the piston and the design of the heat exchangers. The setup is being improved to bring out a second and improved version for attaining the lower cold heat exchanger temperature.
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