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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Wet gas metering

Steven, Richard January 2001 (has links)
Wet Gas Metering is becoming increasingly important to the Oil and Gas Industry. In this research a wet gas flow is defined as a liquid / gas two-phase flow that has a gas mass content greater then 50 %. The Venturi Meter is a favoured wet gas meter in the Oil and Gas Industry. However, industry's understanding of wet gas flow phenomena in such a meter is limited and is therefore forced to accept large metering errors when existing correlations are used to take account of the liquid presence. Furthermore, these correlations all require an input value for the liquid flowrate. This information is not readily available to natural gas production engineers. This research extensively discusses the current wet gas metering situation and then uses new independent data from the NEL Wet Gas Loop to compare the performance of existing correlations when used with a Venturi Meter. This new data is examined to determine parameters that effect the meter reading and then new correlations are presented. One new correlation offered uses the additional information from a downstream pressure tapping in conjunction with the traditional upstream pressure reading and the Venturi pressure differential to predict the gas flowrate without knowledge of the liquid flowrate.
2

Mathematical modelling of venturi and spray tower scrubbers for particle collection

Kuye, A. O. January 1984 (has links)
No description available.
3

The influence of Robert Venturi on Louis Kahn

Rodell, Sam, January 2008 (has links) (PDF)
Thesis (M.S. in architecture)--Washington State University, May 2008. / Includes bibliographical references.
4

Two-phase, two-component critical flow in a Venturi

Smith, R. V. January 1968 (has links)
No description available.
5

Mass streaming via acoustic radiation pressure combined with a Venturi

Uluocak, Osman 07 December 2020 (has links)
Thermoacoustic (TA) engines and generators are one of the latest derivations of the two century-old energy conversion devices that are based on the Stirling cycle. Unlike the traditional Stirling devices, the TA devices use the pressure wavefront of a standing wave created in the working gas, eliminating the power and displacement pistons. The lack of moving parts and the lubrication make these devices practically maintenance-free, making them ideal candidates for space and marine applications. The traditional method for delivering thermal energy to the working fluid (standing wave) would require a heat exchanger, absorbing energy from an external source, and a pump to deliver this energy to the working fluid, however, these components inherently have high losses as well as high cost, hindering overall efficiency. In thermoacoustic systems, the oscillating nature of the working fluid makes it possible to eliminate these components, with most widely applied method being the placement of an asymmetrical gas-diode in a heat carrying loop which is attached to the resonator. Such methods of creating a time-averaged nonzero flow-rate in a preferred direction is called Acoustic Mass Streaming. An alternative to the gas-diode technique to create such pump-less flows is to take advantage of the Acoustic Radiation Pressure (ARP) phenomenon, which is a time-averaged spatially varying pressure of second order amplitude observed in standing wave resonators. Connecting a loop in two different locations to the resonator creates a pressure differential due to the spatial variance which can be further amplified with a converging-diverging nozzle, namely a Venturi. This thesis investigates the fundamentals of this novel acoustic mass streaming method, where the Acoustic Radiation Pressure is combined with a Venturi. Using the thermoacoustic software DeltaEC, the effects of placing a Venturi with different dimensional parameters into the resonator is studied and the changes on the ARP is examined. Considering various types of acoustic losses, the maximum amount of fluid that can be circulated in the pump-less loop is investigated. Time-averaged minor-loss coefficients for converging and diverging acoustic flows at a T-Junction are also presented. / Graduate
6

Boredom's Metamorphosis: Robert Venturi and Saul Steinberg

Mihalache, Andreea Margareta 29 June 2018 (has links)
My dissertation investigates questions of boredom and architecture in the middle decades of the twentieth century through the work of two figures: the American-Italian architect Robert Venturi (b. 1925) and the Romanian-born American architect and artist Saul Steinberg (1914-1999). The topic of boredom in architecture, and specifically within this timeframe, has been largely ignored in architectural history, theory, and criticism where, with the exception of a few articles, there is no consistent body of scholarship on this issue. Looming large in the sterile iterations of various –isms, boredom remains critical in contemporary architectural practice as the production and obsolescence of images becomes ever faster with new technologies. Quickly saturated with information presented in fleeting displays that are easy to produce, easy to delete, and easy to consume, as soon as our expectation for novelty and change fails to satisfy us, we fall back into the loop of boredom. While boredom as the dissociation of person from place has raised architects' interest especially during the middle decades of the twentieth century, there is no significant scholarship on this topic. In this context, my research looks at the work of two architects who go beyond the attractive rhetoric of boredom and explore its potential as both a critical and a generative tool. / PHD / My dissertation investigates questions of boredom and architecture in the middle decades of the twentieth century through the work of two figures: the American-Italian architect Robert Venturi (b. 1925) and the Romanian-born American architect and artist Saul Steinberg (1914-1999). Although the topic of boredom as a disease of modernity has been studied in various fields, such as philosophy, literary studies, sociology, and visual arts, it does not have a presence in architectural scholarship. We live in a world where images are short lived, their production and obsolescence becomes faster with new technologies, and we become quickly bored with everything. In this context, boredom remains critical in contemporary architectural practice where we are quickly saturated with information presented in fleeting displays that are easy to produce, easy to delete, and easy to consume. As soon as our expectation for novelty and change fails to satisfy us, we fall back into the loop of boredom. My research looks at the work of two architects who go beyond the rhetoric of boredom and explore its potential both as a tool of criticism and as a design tool.
7

Influência da vazão e da posição do jato de água na transferência de oxigênio por tubos venturi / Influence of flow rate and water jet position on oxygen transfer by venturi tubes

Gianjacomo, Carlos Henrique 28 April 2017 (has links)
O objetivo desse trabalho foi avaliar o potencial de reoxigenação da água por meio de tubos de Venturi. Os experimentos foram realizados em dois tanques: horizontal (TH) e vertical (TV), com volumes úteis de 100 L e 63 L, respectivamente. Os testes seguiram delineamento experimental associado a metodologia de superfície de respostas, tendo como variáveis independentes a vazão da água (Qágua) e a posição de entrada do jato (Pjato), para um único tubo de Venturi e dois tubos associados em paralelo. Como respostas, foram determinados os coeficientes globais de transferência de oxigênio do ar para a água (KLa) e as eficiências de oxigenação (EO). Os resultados indicam que a vazão da água influenciou significativamente os valores de KLa e EO, enquanto que a posição do jato só teve efeito quando os tubos de Venturi foram associados em paralelo, em ambos os tanques. De maneira geral, os melhores resultados do KLa, de até 50 h-1, foram obtidos para vazões de água mais elevadas e a jato posicionado 15 cm acima da superfície da água. Eficiências de oxigenação de até 2 kgO2 kW-1 h-1 foram observadas para baixos valores de vazão de água. Considerando-se valores experimentais de densidade de potência (DP) e volume de ar injetado por minuto na massa de água, o tanque vertical apresentou desempenho de KLa e EO ligeiramente superior ao horizontal. Os dados experimentais podem ser satisfatoriamente representados pelos modelos matemáticos obtidos. / The objective of this work was to evaluate the reoxygenation potential of water using Venturi tubes. The experiments were performed in two tanks: Horizontal (HT) and vertical (VT), with useful volumes of 100 L and 63 L, respectively. The tests followed the statistical design associated with the surface methodology of responses, having as independent variables the water flow (Qwater) and the inlet position of the jet (Pjet), for a single Venturi tube and two associated tubes in parallel. Were determined as response the global oxygen transfer coefficients from air to water (KLa) and oxygenation efficiencies (OE). The results indicate that the water flow significantly influenced the values of KLa and OE, whereas the position of the jet only had effect when the Venturi tubes were associated in parallel, in both tanks. In general, the best KLa results, up to 50 h-1, were obtained for higher water flows and a jet positioned 15 cm above the water surface. Oxygenation efficiencies of up to 2 kgO2 kW-1 h-1 were observed at low water flow rates. Considering experimental values of power density (DP) and volume of air injected per minute, the vertical tank showed a performance of KLa and EO slightly higher than vertical. The experimental data can be satisfactorily represented by the mathematical models obtained.
8

Influência da vazão e da posição do jato de água na transferência de oxigênio por tubos venturi / Influence of flow rate and water jet position on oxygen transfer by venturi tubes

Gianjacomo, Carlos Henrique 28 April 2017 (has links)
O objetivo desse trabalho foi avaliar o potencial de reoxigenação da água por meio de tubos de Venturi. Os experimentos foram realizados em dois tanques: horizontal (TH) e vertical (TV), com volumes úteis de 100 L e 63 L, respectivamente. Os testes seguiram delineamento experimental associado a metodologia de superfície de respostas, tendo como variáveis independentes a vazão da água (Qágua) e a posição de entrada do jato (Pjato), para um único tubo de Venturi e dois tubos associados em paralelo. Como respostas, foram determinados os coeficientes globais de transferência de oxigênio do ar para a água (KLa) e as eficiências de oxigenação (EO). Os resultados indicam que a vazão da água influenciou significativamente os valores de KLa e EO, enquanto que a posição do jato só teve efeito quando os tubos de Venturi foram associados em paralelo, em ambos os tanques. De maneira geral, os melhores resultados do KLa, de até 50 h-1, foram obtidos para vazões de água mais elevadas e a jato posicionado 15 cm acima da superfície da água. Eficiências de oxigenação de até 2 kgO2 kW-1 h-1 foram observadas para baixos valores de vazão de água. Considerando-se valores experimentais de densidade de potência (DP) e volume de ar injetado por minuto na massa de água, o tanque vertical apresentou desempenho de KLa e EO ligeiramente superior ao horizontal. Os dados experimentais podem ser satisfatoriamente representados pelos modelos matemáticos obtidos. / The objective of this work was to evaluate the reoxygenation potential of water using Venturi tubes. The experiments were performed in two tanks: Horizontal (HT) and vertical (VT), with useful volumes of 100 L and 63 L, respectively. The tests followed the statistical design associated with the surface methodology of responses, having as independent variables the water flow (Qwater) and the inlet position of the jet (Pjet), for a single Venturi tube and two associated tubes in parallel. Were determined as response the global oxygen transfer coefficients from air to water (KLa) and oxygenation efficiencies (OE). The results indicate that the water flow significantly influenced the values of KLa and OE, whereas the position of the jet only had effect when the Venturi tubes were associated in parallel, in both tanks. In general, the best KLa results, up to 50 h-1, were obtained for higher water flows and a jet positioned 15 cm above the water surface. Oxygenation efficiencies of up to 2 kgO2 kW-1 h-1 were observed at low water flow rates. Considering experimental values of power density (DP) and volume of air injected per minute, the vertical tank showed a performance of KLa and EO slightly higher than vertical. The experimental data can be satisfactorily represented by the mathematical models obtained.
9

Process intensification for gas-liquid reactions

Barhey, Avtar Singh January 1996 (has links)
No description available.
10

The Design, Manufacture, and Testing of a Novel Adhesion System for a Climbing Vehicle

Schier, Michael William 01 June 2017 (has links)
We present the design and fabrication of a prototype wall-climbing vehicle employing a unique combined locomotion and adhesion system in which the adhesive vacuum is transmitted through moving, perforated treads. Implementing the adhesion/drive system involved a broad range of design challenges, including: developing reliable sealing of sliding and static interfaces, understanding the frictional interactions between the drive treads and various vehicle components and surfaces on which they ride, as well as designing for lightness, manufacturability, and adjustability. The clean sheet design presented in this thesis was taken from concept to functioning prototype in less than 6 months, requiring a considered mix of off-the-shelf components, custom fabrication, and outsourced production. Proof of concept testing is reviewed, including static pressure and force results as well as dynamic vertical surface maneuverability trials.

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