No description available.

Approved for public release; distribution is unlimited / The objective of the STAR project is to test and space qualify a new continuous cycle cryogenic refrigeration system for cooling of sensors and electronics which is based upon the newly discovered thermoacoustic heat pumping effect. The new refrigerator has no sliding seals, a cycle frequency of about 300 hz, and uses acoustic resonance to enhance the overall power density and efficiency. This thesis is concerned specifically with the design and testing of the electrodynamic transducer which is responsible for the electro-acoustic power conversion. A computer model of the driver/resonator system is presented along with the techniques for measurement of the electrical and mechanical parameters used as input for the model. A final driver design (including dimensional drawings) utilizing a modified JBL 2450J neodymium-iron-boron compression driver and associated leak tight electrical feed-throughs, microphone, accelerometer, pressure gage, pressure housing, and resonator interface is provided. Keywords: Electrodynamic loudspeaker, Thermoacoustic refrigerator / http://archive.org/details/electrodynamicdr00fitz / Lieutenant, United States Coast Guard

This project aimed to design the interior of a Super Premium refrigerator and a freezer of Electrolux directed to a Chinese market. To carry out this, the user and its environment was analysed in detail in order to get as much information as possible to obtain a successful design. The market was also analysed to see the competitive products that other brands could have. Taking into account all the information collected in the analysis some innovative concepts were proposed and from these concepts a solution was obtained which met all the objectives. This final product fits with the daily life of the user. In addition, it gives a touch of innovation to the market of household appliances.

My dissertation emerges from a curiosity about the mundane objects and machines with which we live and it pauses in Britain’s kitchens to ask what we might learn from looking in the fridge. Considered by many to be a rather ordinary and unremarkable appliance, the refrigerator forms a virtually ubiquitous backdrop to routine activities of feeding, provisioning and storing, but rarely is it brought into explicit focus. This study traces the ‘career’ of the mechanical refrigerator and is based upon interviews and archival work in Britain. I unravel intersecting histories and geographies of cooling, discuss a global trade in ice, explore changing understanding of the nature of heat and cold and show how varied ideas and technologies contributed to achieving the creation of artificial cold. The means by which these techniques were translated into the home is central to my discussion and I show how the domestication of refrigeration also played a role in the reconfiguration of associated practices, such as freezing, shopping and eating. I consider the process of normalisation through which refrigerators shifted category from novel products to essential appliances and argue that in many ways the refrigerator has now become integral to the constitution of domestic space. My research follows the lifecourse of the refrigerator and its journeys through multiple sites and spaces, enabling me to analyse diverse refrigerator knowledges and practices from repair shops and recycling facilities to scrap yards and museums, in addition to the home. Although using a refrigerator is frequently dismissed as something ‘self-evident’ or ‘obvious,’ I argue that fridge practices are not innate but learned. I explore ways in which these knowledges travel and pay particular attention to the translation of scientific and technical knowledges into domestic contexts. The ‘reach’ of the domestic refrigerator is considerable and I use one of the more notorious moments in its career, when refrigerators were implicated in global climate change, as a way to show how day to day activities like chilling milk and lettuce can have far-reaching effects at a range of scales.

My dissertation emerges from a curiosity about the mundane objects and machines with which we live and it pauses in Britain’s kitchens to ask what we might learn from looking in the fridge. Considered by many to be a rather ordinary and unremarkable appliance, the refrigerator forms a virtually ubiquitous backdrop to routine activities of feeding, provisioning and storing, but rarely is it brought into explicit focus. This study traces the ‘career’ of the mechanical refrigerator and is based upon interviews and archival work in Britain. I unravel intersecting histories and geographies of cooling, discuss a global trade in ice, explore changing understanding of the nature of heat and cold and show how varied ideas and technologies contributed to achieving the creation of artificial cold. The means by which these techniques were translated into the home is central to my discussion and I show how the domestication of refrigeration also played a role in the reconfiguration of associated practices, such as freezing, shopping and eating. I consider the process of normalisation through which refrigerators shifted category from novel products to essential appliances and argue that in many ways the refrigerator has now become integral to the constitution of domestic space. My research follows the lifecourse of the refrigerator and its journeys through multiple sites and spaces, enabling me to analyse diverse refrigerator knowledges and practices from repair shops and recycling facilities to scrap yards and museums, in addition to the home. Although using a refrigerator is frequently dismissed as something ‘self-evident’ or ‘obvious,’ I argue that fridge practices are not innate but learned. I explore ways in which these knowledges travel and pay particular attention to the translation of scientific and technical knowledges into domestic contexts. The ‘reach’ of the domestic refrigerator is considerable and I use one of the more notorious moments in its career, when refrigerators were implicated in global climate change, as a way to show how day to day activities like chilling milk and lettuce can have far-reaching effects at a range of scales.

My dissertation emerges from a curiosity about the mundane objects and machines with which we live and it pauses in Britain’s kitchens to ask what we might learn from looking in the fridge. Considered by many to be a rather ordinary and unremarkable appliance, the refrigerator forms a virtually ubiquitous backdrop to routine activities of feeding, provisioning and storing, but rarely is it brought into explicit focus. This study traces the ‘career’ of the mechanical refrigerator and is based upon interviews and archival work in Britain. I unravel intersecting histories and geographies of cooling, discuss a global trade in ice, explore changing understanding of the nature of heat and cold and show how varied ideas and technologies contributed to achieving the creation of artificial cold. The means by which these techniques were translated into the home is central to my discussion and I show how the domestication of refrigeration also played a role in the reconfiguration of associated practices, such as freezing, shopping and eating. I consider the process of normalisation through which refrigerators shifted category from novel products to essential appliances and argue that in many ways the refrigerator has now become integral to the constitution of domestic space. My research follows the lifecourse of the refrigerator and its journeys through multiple sites and spaces, enabling me to analyse diverse refrigerator knowledges and practices from repair shops and recycling facilities to scrap yards and museums, in addition to the home. Although using a refrigerator is frequently dismissed as something ‘self-evident’ or ‘obvious,’ I argue that fridge practices are not innate but learned. I explore ways in which these knowledges travel and pay particular attention to the translation of scientific and technical knowledges into domestic contexts. The ‘reach’ of the domestic refrigerator is considerable and I use one of the more notorious moments in its career, when refrigerators were implicated in global climate change, as a way to show how day to day activities like chilling milk and lettuce can have far-reaching effects at a range of scales. / Arts, Faculty of / Geography, Department of / Graduate

A single-stage pulse tube cryocooler was designed and fabricated to provide cooling at 50 K for a high temperature superconducting (HTS) magnet, with a nominal electrical input frequency of 50 Hz and a maximum mean helium working gas pressure of 2.5 MPa. Sage software was used for the thermodynamic design of the pulse tube, with an initially predicted 30 W of cooling power at 50 K, and an input indicated power of 1800 W. Sage was found to be a useful tool for the design, and although not perfect, some correlation was established. The fabricated pulse tube was closely coupled to a metallic diaphragm pressure wave generator (PWG) with a 60 ml swept volume. The pulse tube achieved a lowest no-load temperature of 55 K and provided 46 W of cooling power at 77 K with a p-V input power of 675 W, which corresponded to 19.5% of Carnot COP. Recommendations included achieving the specified displacement from the PWG under the higher gas pressures, design and development of a more practical co-axial pulse tube and a multi-stage configuration to achieve the power at lower temperatures required by HTS.

Voluntary environmental labeling or certification programs provide information about the environmental characteristics of one or more aspects of a product’s life cycle to consumers. The U.S. Environmental Protection Agency and Department of Energy were among the first governmental agencies in the world to adopt environmental information programs. This study examines two U.S. programs – Energy Star, an energy efficiency labeling program, and Green Power Partnership (GPP), a green energy purchasing program, and estimates how much consumers are willing to pay for refrigerators that have been awarded these labels and what factors motivate that willingness to pay. The data were obtained from a survey conducted in March and April of 2009 via an online research panel, which was constructed to be representative of the U.S. population. Analysis of the data was conducted using conditional logit regression models with fixed parameters and mixed logit regression models with random parameters. Results revealed that consumers, on average, have a willingness to pay ranging from $237.81 to $350.54 for the Energy Star label and a willingness to pay ranging from $48.52 to $70.95 for the GPP label. The results also indicate that consumer demographics and attitudes influence WTP. In particular, individuals with greater levels of stated concern for the environment or individuals exhibiting strong perceptions on the effectiveness of consumers to affect product design and the ambient environment had a greater likelihood of choosing a labeled alternative, and thus, a greater WTP for both the Energy Star and GPP label. To manufacturers and government regulators, these results suggest that energy labels can play a significant role in a consumer’s decision making process when selecting a new appliance.

Voluntary environmental labeling or certification programs provide information about the environmental characteristics of one or more aspects of a product’s life cycle to consumers. The U.S. Environmental Protection Agency and Department of Energy were among the first governmental agencies in the world to adopt environmental information programs. This study examines two U.S. programs – Energy Star, an energy efficiency labeling program, and Green Power Partnership (GPP), a green energy purchasing program, and estimates how much consumers are willing to pay for refrigerators that have been awarded these labels and what factors motivate that willingness to pay. The data were obtained from a survey conducted in March and April of 2009 via an online research panel, which was constructed to be representative of the U.S. population. Analysis of the data was conducted using conditional logit regression models with fixed parameters and mixed logit regression models with random parameters. Results revealed that consumers, on average, have a willingness to pay ranging from $237.81 to $350.54 for the Energy Star label and a willingness to pay ranging from $48.52 to $70.95 for the GPP label. The results also indicate that consumer demographics and attitudes influence WTP. In particular, individuals with greater levels of stated concern for the environment or individuals exhibiting strong perceptions on the effectiveness of consumers to affect product design and the ambient environment had a greater likelihood of choosing a labeled alternative, and thus, a greater WTP for both the Energy Star and GPP label. To manufacturers and government regulators, these results suggest that energy labels can play a significant role in a consumer’s decision making process when selecting a new appliance.

An experimental study has been performed to investigate the condensation on the inner surface of open cavities located on horizontal and vertical surfaces of a refrigerator to simulate ice dispensers, water dispensers, electronic display slots, and door handles, etc. Cavity size, cavity depth and insulation thickness were variable parameters. Cavities were located on fresh food and freezer compartments to study two different boundary conditions. Level of condensation was put into a scale based on visual observation for condensed water droplets on the cavity surface. As a practical tool for design engineers, insulation thickness was plotted as a function of cavity depth indicating the level of condensation. Similar cavity geometries were tested on both freezer and fresh food compartments. Aluminum foil attached behind the inner surface of a cavity located on the fresh food door helped to decrease the level of condensation significantly. However, condensation can not be avoided for the cavities located on the freezer compartment deeper than critical values. Forming radius at the corners and on the edges of cavities decreased condensation on these regions. The effects of air circulation on condensation inside and outside the refrigerator were also investigated for some cavities. Particle Image Velocimetry (PIV) method was used to visualize non-disturbed air flow pattern over the cavity and at the cavity opening. High convective heat transfer at the cavity center was strongly associated with relatively high air velocity. Temperature distribution and flow pattern were analyzed by a CFD Programme. Condensation due to relatively low temperatures at the corners and on the edges was associated with conductive heat transfer in multiple directions and insufficient air circulation on these regions.