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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.
101

Flow problems with respect to intakes and tunnels of Swedish hydro-electric power plants

Rahm, Lennart. January 1953 (has links)
Thesis--Tekniska högskolan, Stockholm. / Extra t.p., with thesis statement, inserted. Published also as the Royal Institute of Technology, Stockholm, Transactions, no. 71. Includes bibliographical references.
102

Dynamics and stability issues of poppet type pressure relief valves /

Pfeiffer, Ferris M., January 2004 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaves 83-88). Also available on the Internet.
103

Floodplain and flood probability mapping using geodatabases /

Gallup, Douglas J., January 2005 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Civil and Environmental Engineering, 2005. / Includes bibliographical references (p. 57-58).
104

Dynamics and stability issues of poppet type pressure relief valves

Pfeiffer, Ferris M., January 2004 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaves 83-88). Also available on the Internet.
105

Molecular dynamics simulation of electroosmotic & pressure driven flows in nanochannels

Miao, Miao, January 2007 (has links) (PDF)
Thesis (M.S.)--Washington State University, August 2007. / Includes bibliographical references (p. 73-77).
106

Accurate Cylindrical-Coordinate Numerical Models For The Analysis Of Hydrologic Tests

Keller, John Edward 01 January 2009 (has links)
Analytical solutions to well hydraulic problems have restrictive assumptions that often do not match real world conditions. Although numerical models more closely match reality, they either ran too slowly to be practical or lacked accuracy because of coarse grid spacing and large time steps. Advances in computer power over the last few decades now allow for accurate, fast numerical models that handle complex flow systems. The purpose of this dissertation was to develop flexible and accurate numerical modeling codes for the simulation of hydrologic tests. One of these numerical modeling codes, the Slug Test Simulator (STS), was designed for the mechanics of a single well test, or slug test. STS can handle a variety of conditions including unconfined flow, partial penetration, layered heterogeneities, and the presence of a homogeneous well skin like existing codes. This program also extends on the capabilities of earlier codes with its ability to simulate a heterogeneous skin where K can vary in both the radial and vertical directions. STS has a clear user interface, can display graphical results, and allows the user to determine hydraulic conductivity through a trial-and-error curve-matching process. Comparisons of STS to the Cooper-Bredehoeft-Papadopulos analytical solution and the Kansas Geological Survey (KGS) semi-analytical solution produced near-identical curves under a wide variety of conditions. Numerous analytical studies have shown that the well skin is an important factor in the underestimation of hydraulic conductivity in slug tests. STS allows for the exploration of the well skin issue under conditions too complex for analytical models. Model trials revealed two key discoveries: 1) if any layers within the skin have the same hydraulic conductivity as the surrounding formation, flow is concentrated within these conduits and the resultant head response approaches the case when no skin is present; and 2) the two most important properties in determining the overall influence of the skin are specific storage and skin thickness. The first discovery suggests that extensive development activities can essentially eliminate any well skin impacts. Other factors such as partial penetration, the placement of the well screen, and anisotropy play insignificant roles in resultant head responses. Recent research is focusing on alternative direct- push (DP) methodologies to determine hydrologic properties. DP offers advantages over traditional well tests, but may yield inaccurate results if the screen becomes clogged during pushing activities. The Kansas Geological Survey (KGS) developed a new DP technique, the Direct-Push Permeameter (DPP), to overcome this limitation. Existing analytical or numerical models cannot address the specialized nature of DPP tests so a second numerical modeling code, the Direct Push Permeameter Simulator (DPSS), was developed. DPPS was generated by modifying STS so both numerical codes are similar in many ways, particularly with their flexibility and accuracy. The codes differ in how they handle vertical layering, the boundary conditions at the well, and the spreadsheet interfaces. DPPS was able to produce near-identical curves in comparison to the Theis analytical solution. DPPS was also able to reasonably recreate DPP field data conducted at two sites with distinctly different media properties. The GEMS and Nauen sites had an average error of 14.2% and 3.1%, respectively between the field data and DPPS simulations.
107

Modelo numerico para solucao termohidraulica de um trocador de calor de carcaca e tubos U com chicanas segmentais

BAPTISTA FILHO, BENEDITO D. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:07Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:41Z (GMT). No. of bitstreams: 1 00704.pdf: 3086800 bytes, checksum: 4bfb1ba852db657382cd5847fae91fe8 (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
108

Modelo numerico para solucao termohidraulica de um trocador de calor de carcaca e tubos U com chicanas segmentais

BAPTISTA FILHO, BENEDITO D. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:07Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:41Z (GMT). No. of bitstreams: 1 00704.pdf: 3086800 bytes, checksum: 4bfb1ba852db657382cd5847fae91fe8 (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
109

Environmental Hydraulics, Turbulence and Sediment Transport / Environmental Hydraulics, Turbulence and Sediment Transport

Pu, Jaan H. 01 March 2022 (has links)
Yes / In the research on environmental hydraulics, its turbulence and sediment transport, constant challenges have been faced. The complexity of hydraulic impacts towards sediment morphology and turbulent flow properties makes research in this area a difficult task. However, due to pressure from climate change and the mounting issue of pollution, environmental flow studies are more crucial than ever. Bedforming within rivers is a complex process that can be influenced by the hydraulics, vegetated field, and various suspended and bedload transports. Changes in flow conditions due to rain and flood can further complicate a hydraulic system. To date, the turbulence, morphologic, and bedforming characteristics of natural environmental flows are still not well understood. This book aims to bring together a collection of state-of-the-art research and technologies to form a useful guide for the related research and engineering communities. It is useful for authorities and researchers interested in environmental and civil engineering studies, as well as for river and water engineers to understand the current state-of-the-art practices in environmental flow modelling, measurement and management. It is also a good resource for research, post-, or undergraduate students who wish to know about the most up-to-date knowledge in this field.
110

Environmental Hydraulics, Turbulence and Sediment Transport

Pu, Jaan H. 23 March 2022 (has links)
Yes

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