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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.
191

Geographical Information System (GIS) web applications for data visualization of Drinking Water pipelines

Shekhawat, Pururajsingh 08 August 2018 (has links)
Robust decision support tools that aid water utilities to make informed, swift and precise decisions are becoming the need of the hour. Application of sophisticated models to aid the process of condition assessment and risk analysis on water pipelines have been limited owing to the lack of scalability, inability to incorporate external open source datasets and mathematically complicated output results. Interactive visualization of resultant model output is the key element in extracting valuable information to support decision making. This thesis presents a framework for visualization of data related to drinking water pipelines. Critical components of strategic, tactical and operational level decision making are explored in context with data presentation and information depiction. This thesis depicts various aspects of developing GIS web applications and their important functionalities for query and visualization of data. Multiple facets of data storage, standardization and application development are highlighted in this document. Publishing of application geo processing services in web environment is done through Virginia Tech enterprise geodatabase. Risk assessment and Performance models developed by a utility are projected in the application environment through help of widgets. Applications are coded into links on a Drupal website (www.pipeid.org) for model dissemination and utility engagement purposes. / Master of Science / Drinking water supply network primarily consists of pipelines, pumping stations, reservoir basins and treatment plants. Water pipelines are routinely inspected to check their condition and maintain appropriate water quality. Management of these subsurface assets should be given prime importance for maintaining high standards of services at acceptable cost to customers. An integral step in accomplishing this task is to view pipeline network in a geographic map. Different factors affecting pipeline condition are displayed on the map in the form of individual layers. Such real-world problems are analyzed with the help of Geographical Information System (GIS) tools that incorporate spatial features with tabular information. Moreover, interpretation of raw data into meaningful insights and distribution of allocated knowledge to all the concerned parties can be efficiently accomplished using rich internet applications. This thesis presents a framework to use GIS tools for developing web applications using raw data samples from contacted water utilities. Sample web applications are created and discussed in the form of case studies. Also, the challenges in water utility sector with respect to utilizing GIS tools for supporting daily decision-making processes is highlighted in this document. The recommendation to improve the suggested framework and adding more functionalities to developed applications are presented at the end with references.
192

A mathematical model of transient flow in pipeline filling

Badger, David R. January 1986 (has links)
A mathematical model was developed for the rapid filling of an initially dry pipe. The pipe was assumed to be horizontal and to contain an orifice at the downstream end. The key elements of the model were the momentum equation governing the flow of the water, the thermodynamic equations for the compression and discharge of the entrapped air, and the equations for waterhammer resulting from the impact of the water with the orifice. A computer program of this model was then developed and tested. After initial testing, the model was used to examine the magnitudes of the pressures that could be produced from waterhammer and air compression for various lengths of pipe. The effects that different orifice diameters had on the flow were also analyzed. The results indicated that extremely high pressures can be generated from both waterhammer and air compression during the filling process. These pressures tend to increase as the orifice diameter is reduced. However, below a certain size the orifice constricts the air discharge enough to stop the water prior to its reaching the orifice. This results in an oscillatory behavior of the flow, and the relation between waterhammer and orifice diameter becomes much more difficult to predict. The results also demonstrated that these pressures are significantly reduced for longer pipe lengths, and for pipes with smaller diameters or otherwise offering greater frictional resistance to the flow. / M.S.
193

A coal-air flowmeter for measuring the air-fuel ratio in a pulverized coal carrying pipe line

Giddings, Stanley M., Speegle, Hobart January 1949 (has links)
M.S.
194

Guidelines for Implementing Risk-Based Asset Management Program to Effectively Manage Deterioration of Aging Drinking Water Pipelines, Valves and Hydrants

Aprajita, Fnu 31 July 2018 (has links)
There is an unprecedented need to manage our deteriorating water infrastructure systems effectively to mitigate the enormous consequences of their premature failure such as loss of service, money, time, damage to other infrastructure, and damage to property. Most of the water utilities understand this need and are implementing asset management approaches and technologies to increase the overall service life of their assets. However, to indeed achieve sustainable water infrastructure systems, there is a requirement to implement a risk-based asset management program which provides a more comprehensive approach to manage these aging assets. A risk-based asset management program assesses and manages the risk of failure associated with the water infrastructure assets and helps water utilities in prioritizing their assets for renewal. This program identifies the critical assets for renewal and saves the money and time invested in the renewal of 'not so critical' assets. This research incorporates an extensive literature and practice review on risk-based asset management of pipes, valves, and hydrants. The risk-based asset management consist of the following four major components: (1) understanding the deterioration modes and mechanisms, (2) implementing risk assessment and management approaches, (3) implementing condition assessment approaches and technologies, and (4) implementing asset renewal approaches and technologies. This research aims to provide enhanced guidelines based on the EPA 10 step asset management program which will help water utilities in developing a risk-based asset management program as well as in improving their existing asset management program. This research combines the in-depth knowledge gained through a state-of-the-art literature review and practice review. The practice review is conducted to capture the real world application of the risk-based asset management through interviews with the water utilities across the united states. This research has also compiled the knowledge gained by already published case studies to provide a more comprehensive overview of the current practices and trend in the risk-based asset management of drinking water pipelines, valves, and hydrants. / Master of Science / America’s drinking water infrastructure is deteriorating and there is an unprecedented need to manage our deteriorating water infrastructure systems effectively to mitigate the enormous impacts of their premature failure such as loss of service, money, time, damage to other infrastructure, and damage to property. In order to achieve sustainable water infrastructure systems, there is a requirement to implement a risk-based asset management program which is a comprehensive approach to manage these aging assets. A risk-based asset management program assesses and manages the risk of failure associated with the water infrastructure assets and helps water utilities in prioritizing their assets for renewal. This program identifies the critical assets for renewal and saves the money and time invested in the renewal of “not so critical” assets. This research aims to provide enhanced guidelines based on the EPA 10 step asset management program which will help water utilities in developing a risk-based asset management program as well as in improving their existing asset management program. This research combines the in-depth knowledge gained through a state-of-the-art literature review and practice review. The practice review is conducted to capture the real-world application of the risk-based asset management through interviews with the water utilities across the united states. This research has also compiled the knowledge gained by already published case studies to provide a more comprehensive overview of the current practices and trend in the risk-based asset management of drinking water pipelines, valves, and hydrants.
195

3D modeling of large elongated structures for non-destructive testing and inspection

Hesabi, Somayeh 24 April 2018 (has links)
Selon un rapport de l’Agence centrale de renseignement (CIA) ¹, présenté dans un journal NDT ², il y avait un total de 3.3 millions km de pipelines dans 120 pays du monde en 2014. Cela signifie que les pipelines ont un rôle important à jouer dans l’infrastructure de l’énergie pour le transport de liquides ou du gaz naturel. Bien que les pipelines représentent le plus efficace et le plus fiable pour transporter divers liquides allant de l’eau à l’huile, ils sont vulnérables aux défauts externes et internes. Heureusement, une inspection périodique des pipelines peut augmenter leur sécurité et leur fonctionnalité et réduire les catastrophes environnementales ainsi que les pertes économiques causées par les potentielles explosions ou autres dysfonctionnements. Considérant les avantages des capteurs 3D qui permettent de créer une réplique numérique précise de la surface des objets réels en plus des avantages de la technologie d’Evaluation Non Destructive (END) qui fournit un suivi des défauts sous la surface, la présente recherche propose une solution visant à construire un modèle 3D d’un pipeline ou d’autres structures allongées pour suivre leur état. Dans ce but, nous mesurons d’abord la géométrie du pipeline avec des capteurs 3D portables et construisons le modèle 3D de la structure. Ensuite, les informations des défauts sous la surface qui sont estimées efficacement par des approches développées par d’autres membres de l’équipe en utilisant la thermographie infrarouge sont intégrées au modèle 3D reconstruit. Le manuscrit étudie différents défis liés à la modélisation 3D précise de grandes structures allongées et la répétabilité de l’approche de modélisation à des fins de contrôle de qualité et d’entretien à long terme. 1. The World Factbook, updated 18 May 2015. 2. Materials Evaluation (M.E.), vol. 73, no. 7, July 2015 / According to a Central Intelligence Agency (CIA) report ¹ presented in a flagship NDT journal ², there were a total of 3.3 million km of pipelines present in 120 countries in the world in 2014. This means that pipelines play an important role in the energy infrastructure in order to safely transport liquid or natural gas. Although pipelines are the most efficient and reliable way to carry various liquids ranging from water to oil, they are vulnerable to external and internal damages. Fortunately, a periodic inspection of pipelines can increase their functionality and decrease the environmental disasters as well as economic losses caused by potential spills, explosions or other malfunctions. In this context of the exploitation of pipelines and other similar elongated structures and considering the benefits of 3D sensors which allow us to create an accurate digital replica of the surface of physical objects in addition to the advantages of Non-Destructive Testing (NDT) technology which provides the ability of under-surface monitoring, our research proposes a solution to build a 3D model of pipeline or other elongated structures to monitor their status. For this purpose, we first measure the geometry of the pipeline by handheld 3D scanners and construct the 3D model of the structure. Then, the information of subsurface defects that is estimated efficiently by approaches developed by other team members using infrared thermography is integrated to the reconstructed 3D model. The manuscript investigates different challenges related to the 3D modeling of large elongated structures with high accuracy and repeatability for quality control purposes as well as for long-term maintenance. 1. The World Factbook, updated 18 May 2015. 2. Materials Evaluation (M.E.), vol. 73, no. 7, July 2015
196

Numerical modelling of pipeline construction / Alexander Dunstone.

Dunstone, Alexander January 2004 (has links)
"February, 2004." / Bibliography: leaves 231-249. / xxvii, 261 leaves : ill. (some col.), plates, photos (col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Examines ways of reducing the risk of hydrogen assisted cold cracking in pipeline construction by modifying the construction procedure to reduce residual stress and hydrogen concentration. A numerical model of the pipeline construction procedure capable of modelling the process in a transient sense was created. Experimental validation of the model involved using the "blind hole drilling" strain gauge method of residual stress measurement. The diffusion of hydrogen during welding was modelled using a scheme based on Fick's Second Law of Diffusion, finding that the parameters which dominate the rate of diffusion are the timing of the weldment process, joint geometry, pre-heating and post-heating. / Thesis (Ph.D.)--University of Adelaide, School of Mechanical Engineering, 2004
197

Identification of flow patterns for coarse particles transported in a non-Newtonian carrier using electrical resistance tomography

Kabengele, Kantu January 2012 (has links)
A dissertation submitted to the Faculty of Engineering, Cape Peninsula University of Technology, Cape Town, in partial fulfilment of the requirements for the MTech Degree in Mechanical Engineering 2012 / Flow features provide considerable guidance for the rational selection of techniques to predict hydraulic behaviour and for suitable operating conditions for pipelines. Traditionally, water was used to transport coarse particles, and it was necessary to operate at velocities at which the flow was turbulent in order to avoid blockage. Consequently the friction losses were too high for economic operation. In addition, wear on pipes, fittings and pumps presented serious problems. Nowadays, it is well established that it is possible to operate at very high solids concentration in a heavy vehicle (carrier fluid). Similar solids throughputs may be achieved at very much lower velocities by operating in the laminar flow regime. This results not only in lower power requirement, but it also reduces wear and water consumption. In spite of these potential benefits, only a few studies dealing with the transport of coarse particles in heavy media have been reported. Since the distinction between different flow patterns is of paramount importance for modelling purposes, as equations are flow pattern dependent, and given the importance of avoiding excessive wear of pipes at low and high velocities, the present work was carried out in the context of dense or non-Newtonian carrier fluid. This project comprised analysis of existing data acquired at the Flow Process and Rheology Centre of the Cape Peninsula University of Technology. Kaolin in the range of 6% to 15% volumetric concentration was used as a carrier fluid and coarse material in the range of 10% to 30% volumetric concentration was simulated by silica sand ranging in size from 1 mm to 3 mm. For the purpose of this study flow patterns derived from resistance curves for various mixtures, particle concentrations, particle grading and flow conditions were compared with “concentration profiles” and images obtained from electrical resistance tomography (ERT). It appeared from this work that the sand concentration does not change the flow pattern but increases or reduces the pressure gradients depending on the case. The concentration of kaolin carrier can change the flow patterns from layered to homogeneous flow, inducing an increase in total pressure gradients as it increases. Flow patterns obtained from ERT compared reasonably well with those derived from pressure gradients profiles. The transition velocities from layered to heterogeneous flow obtained from both methods were similar, especially for low and moderate carrier concentrations. As the kaolin carrier concentration or as the sand concentration increased it became more difficult to distinguish the transition velocity between heterogeneous and layered flow. More work is still needed to improve the ERT instrument and its image reconstruction software.
198

An environmental impact assessment of the two possible routes for the proposed magnetite slurry pipeline between Phalaborwa and Maputo

Ueckermann, Ilze 13 August 2012 (has links)
M.A. / The study of the two possible routes for the magnetite slurry pipeline between Phalaborwa and Maputo was motivated because of the impact it can have on the environment. Since the early 1970's the environment has become more and more important to the people that live in it. By law any development should by forgone by an Environmental Impact Assessment, and for that reason this study was undertaken. Environmental Impact Assessment (E.I.A.) measures impacts of one or more environmental indicators on the environment. Further more an Environmental Impact Assessment means a national procedure for evaluating the likely impact of a proposed activity on the environment. It is thus a tool used to minimise the impacts of human development on the environment. This tool will be used to compare the two routes and to identify the route with less Environmental Impact. Within the growing field of environmental science and engineering, there is increasing interest in and use of Environmental Assessment (EA). In this form of assessment, the experts evaluate the probable impact of a range of alternative actions that have been proposed in response to a problem, in this case the placing of a pipeline from Phalaborwa to Maputo. Environmental Impacts may be considered in light of economic, social, or security constraints; hence the lightest impact is not necessarily always chosen by planners.
199

Ruská federace - energetická politika a ekonomizace zahraniční politiky / Russian federation - energy policy and economization of foreign policy

Řezáč, Tomáš January 2011 (has links)
The paper clearly shows that Russia has been diversifying its export routes during past 20 years, in order to by-pass third countries and to avoid paying additional transportation fees. The overall Russian export capacities of oil and gas are increasing, but in the same time the export volumes are stagnant. In case of oil transportation, pipelines are progressively substituted by sea transport, which enables Russia to participate on the world market. Situation with gas is different. Despite increasing export capacity Russia nowadays export almost the same amount of gas to the same locations as it did in 1990. It means that if there is any political or economical pressure it is laid against transition countries, which can be substituted, rather than against importing countries. Russian economical gains from export are following increasing oil and gas prices. To make the gains even higher, Russia initiated transition to world gas prices in the CIS countries as well as at the domestic market. To support the hypothesis of this thesis that primary goal of Russia is to increase its economical gains rather than to strengthen its political leverage, it is important to mention that majority of energy disputes of past twenty years were ignited by quarrel over prices and were settled by trade agreement. The...
200

Stress corrosion cracking and corrosion of carbon steel in simulated fuel-grade ethanol

Lou, Xiaoyuan 08 November 2010 (has links)
Today, ethanol, as well as other biofuels, has been increasingly gaining popularity as a major alternative liquid fuel to replace conventional gasoline for road transportation. One of the key challenges for the future use of bioethanol is to increase its availability in the market via an efficient and economic way. However, one major concern in using the existing gas-pipelines to transport fuel-grade ethanol or blended fuel is the potential corrosion and stress corrosion cracking (SCC) susceptibility of carbon steel pipelines in these environments. Both phenomenological and mechanistic investigations have been carried out in order to address the possible degradation phenomena of X-65 pipeline carbon steel in simulated fuel-grade ethanol (SFGE). Firstly, the susceptibilities of stress corrosion cracking of this steel in SFGE were studied. Ethanol chemistry of SFGE was shown to have great impact on the stress corrosion crack initiation/propagation and the corrosion mode transition. Inclusions in the steel can increase local plastic strain and act as crack initiation sites. Secondly, the anodic behavior of carbon steel electrode was investigated in detail under different ethanol chemistry conditions. General corrosion and pitting susceptibility under unstressed condition were found to be sensitive to the ethanol chemistry. Low tendency to passivate and the sensitivity to ethanol chemistry are the major reasons which drive corrosion process in this system. Oxygen plays a critical role in controlling the passivity of carbon steel in ethanol. Thirdly, the detailed study was carried out to understand the SCC mechanism of carbon steel in SFGE. A film related anodic dissolution process was identified to be a major driving force during the crack propagation. Fourthly, more detailed electrochemical impedance spectroscopy (EIS) studies using phase angle analysis and transmission line simulation reveal a clearer physical picture of the stress corrosion cracking process in this environment. Fifthly, the cathodic reactions of carbon steel in SFGE were also investigated to understand the oxygen and hydrogen reactions. Hydrogen uptake into the pipeline steel and the conditions of the fractures related to hydrogen embrittlement were identified and studied.

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