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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.
201

Virtual access hydraulics experiment for system dynamics and control education

Koeppen, Kyle Bruce 05 1900 (has links)
No description available.
202

Design and evaluation of a remote access hydraulic manipulator for system dynamics and controls education

Rouse, Matthew David 05 1900 (has links)
No description available.
203

Experimental thermal-hydraulic study of a supercritical CO2 natural circulation loop

Mahmoudi, Javad 27 March 2014 (has links)
Experimental thermal-hydraulic study of a rectangular supercritical CO2 natural-circulation loop with a horizontal heated channel was conducted at different steady-state conditions. These included different system pressures and three different inlet temperatures, with different inlet and outlet valve openings. Approximately, 450 experimental steady-state data-points were collected. The data include measurements of pressure-drop along the heated channel, pressure-drop across inlet and outlet valves, applied heat on the heated channel, pressure, temperature and flow-rate. Steady-state curves of mass flow-rate versus power, outlet temperature versus power, and detailed information of frictional pressure drop and local head loss coefficients were produced. Comparison showed that for the available experimental set-up, computed frictional pressure-drops fell within 1-1.20 of the Blasius formula prediction. Moreover, flow oscillations were observed in several cases when outlet temperature of CO2 was higher than the pseudo-critical temperature on the negative slope part of the mass flow-rate versus power curve.
204

Construction of tilt table with high loads : A construction with complete hydraulic system / Konstruktion av tiltbord med hög last : En konstruktion med komplett hydraulsystem

Janebrink, Niklas January 2014 (has links)
At Uddeholm AB, they today use two overhead cranes with chains to move and tilt steel sheets for visual inspection of surface defects. The tilting is done to give the operator a better view of these defects using reflection of light. The problem with this approach is that it is combined with danger of life with hanging load, in case a chain breaks. Therefore Uddeholm AB would like to develop a tilt table that can be mounted on their lift table they use today. To solve this problem, 5 concepts was developed using a product development process. The chosen concept was further developed into a product that met the defined load case to tilt the sheets, weighing up to 20 tonnes, 55 degrees. The design that was selected use two points of rotation and is driven by three hydraulic cylinders. The structure has been calculated by hand and with the structural mechanics software Ansys. To tilt the table a complete hydraulic system was developed and dimensioned. The hydraulic system has been calculated by hand and simulated by a computer program called Hopsan developed at Linköping University. / På Uddeholm AB använder man idag två traverser med kedjor för att flytta och tilta stålplåtar för syning av ytdefekter. Tiltningen sker för att operatören lättare ska kunna se dessa defekter med hjälp av ljusreflektioner. Problemet med detta arbetssätt är att det är förenat med fara för liv med hängade last då en kedja skulle kunna gå av. Därför vill Uddeholm AB ha hjälp att utveckla ett tiltbord som kan monteras på deras lyftbord som används idag. I detta arbete togs det fram 5 koncept med hjälp av en produktutvecklingsprocess för att lösa problemet. Ett koncept valdes som utvecklades till en produkt som klarar det definierade lastfallet att tilta plåtar som väger upp till 20 ton 55 grader. Den valda designen som valdes använder två rotationspunkter och drivs av 3 hydraulcylindrar. Konstruktionen beräknades för hand och med strukturmekanikprogrammet Ansys. För att driva konstruktionen utvecklades och dimensionerades även ett komplett hydraulsystem. Hydraulsystemet har beräknats för hand och simulerats av ett datorprogram som kallas för Hopsan som utvecklats vid Linköpings universitet.
205

A Robust Four-Fluid Transient Flow Simulator as an Analysis and Decision Making Tool for Dynamic Kill Operation

Haghshenas, Arash 03 October 2013 (has links)
The worst scenario of drilling operation is blowout which is uncontrolled flow of formation fluid into the wellbore. Blowouts result in environmental damage with potential risk of injuries and fatalities. Although not all blowouts result in disaster, outcomes of blowouts are unknown and should be studied before starting an operation. Plans should be available to prevent blowouts or provide safe and secure ways of controlling the well before the drilling operation starts. The plan should include procedures in case of any blowout incident as a proactive measure. A few commercial softwares are available in the industry for dynamic kill and transient modeling. All models are proprietary and very complex which reduces the flexibility of the program for specific cases. The purpose of this study is to develop a pseudo transient hydraulic simulator for dynamic kill operations. The idea and concept is to consider the flow of each phase as a single phase flow. The summation of hydrostatic and frictional pressure of each phase determines the bottomhole pressure during the dynamic kill operation. The simulator should be versatile and capable of handling special cases that may encounter during blowouts. Some of the main features of the proposed dynamic kill simulator include; quick and robust simulation, fluid properties are corrected for pressure and temperature, sensitivity analysis can be performed through slide bars, and capable of handling variety of wellbore trajectories. The results from the proposed simulator were compared to the result of commercial software, OLGA ABC. The results were in agreement with each other. It is recommended to apply the simulator for operations with required kill fluid volumes of one to two wellbore volumes.
206

Documentation and testing of the WEAP model for the Rio Grande/Bravo Basin

Danner, Constance L. January 2006 (has links) (PDF)
Thesis (M.S. in Engineering)--University of Texas at Austin, 2006. / "August 2006." Description based on title screen as viewed on June 1, 2010. DTIC Descriptor(s): Computer Programs, Ground Water, Basins (Geographic), Computerized Simulation, Volume, Water Flow, Reservoirs, Mexico, North America, Streams, Banks (Waterways), Models, Physical Properties, Theses. DTIC Identifier(s): Rio Grande/Bravo Basin, Water Evaluation and Planning System, WEAP (Water Evaluation and Planning System), Weap Model, IBWC (International Boundary and Water Commission). Includes bibliographical references (p. 39-41). Also available in print.
207

The dynamics of unsteady strait and sill flow

Pratt, Lawrence J. January 1982 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1982. / Bibliography: p. 139-140.
208

Applying thermal hydraulics modeling in coupled processes of nuclear power plants /

Hämäläinen, A. January 1900 (has links) (PDF)
Thesis (doctoral)--Lappeenranta University of Technology, 2005. / Includes bibliographical references. Also available on the World Wide Web. Myös verkkojulkaisuna.
209

Influence of stress states on soil-water characteristics, conjunctive surface-subsurface flow modelling and stability analysis /

Tse, Man Kit. January 2007 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 145-154). Also available in electronic version.
210

An experimental study of the hydraulic characteristics beneath a partial ice cover

Peters, Mitchel 11 January 2016 (has links)
While many studies have been conducted in channels that are fully open or entirely covered with ice, little has been examined in channels with border ice. To begin filling in this gap in knowledge, experiments were conducted in the Hydraulics Research Testing Facility at the University of Manitoba in a 1.2m wide, 14m long flume to assess the impact of Froude number, coverage ratio and bed-to-ice roughness ratio on the hydraulic characteristics of channels with border ice cover. Acoustic Doppler velocimetry was used to collect detailed 3D velocity data over a cross section of the flume which facilitated the analysis of velocity and turbulence intensity fields as well as the shear stress distribution. The data collected thus far represents the most complete experimental dataset of measured water velocities in a channel with a border ice cover. / February 2016

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