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Assessing the Hydraulic Transient Performance of Water and Wastewater Systems Using Field and Numerical Modeling DataRadulj, Djordje 27 July 2010 (has links)
A large proportion of water and wastewater systems have traditionally been analyzed and designed without the consideration of the nature, risk, and potential consequence of hydraulic transients. Recent advancements in numerical hydraulic modeling have spawned a specialty hydraulic field based on numerical transient analysis. The current practice within this field often lacks physical understanding and can be misguided by both the current knowledge, technology based limitations, and by the sole reliance on numerical models. This thesis aims to provide insights into some of the shortcomings of current practice and to develop the importance and application of field data based confirmations. The thesis examines the advances in the current field oriented technology for recording transient pressures, and provides examples and insights on how this data can be used both in conjunction with numerical modeling and on its own as a first step to a proposed frequency based transient risk assessment methodology. The thesis establishes definitions and a preliminary methodology for a Transient Risk Index.
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Assessing the Hydraulic Transient Performance of Water and Wastewater Systems Using Field and Numerical Modeling DataRadulj, Djordje 27 July 2010 (has links)
A large proportion of water and wastewater systems have traditionally been analyzed and designed without the consideration of the nature, risk, and potential consequence of hydraulic transients. Recent advancements in numerical hydraulic modeling have spawned a specialty hydraulic field based on numerical transient analysis. The current practice within this field often lacks physical understanding and can be misguided by both the current knowledge, technology based limitations, and by the sole reliance on numerical models. This thesis aims to provide insights into some of the shortcomings of current practice and to develop the importance and application of field data based confirmations. The thesis examines the advances in the current field oriented technology for recording transient pressures, and provides examples and insights on how this data can be used both in conjunction with numerical modeling and on its own as a first step to a proposed frequency based transient risk assessment methodology. The thesis establishes definitions and a preliminary methodology for a Transient Risk Index.
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Towards Simplified Tools for Analysis of Reinforced Concrete Structures Subjected to Impact and Impulsive Loading: A Preliminary InvestigationTrommels, Heather 17 July 2013 (has links)
The analysis of reinforced concrete structures under blast and impact loads is an area of research that has become increasingly relevant in recent years. Complex hydrocodes are typically used for impact analyses, although single-degree-of-freedom methods have also been developed. There are a number of disadvantages associated with both methods, and the Canadian Nuclear Safety Commission (CNSC) is looking for a tool that can be used in conjunction with hydrocodes to analyze hard and soft missile impacts, with target damage ranging from flexural cracking to perforation.
The VecTor programs, a suite of nonlinear finite element programs developed at the University of Toronto for the analysis of reinforced concrete structures, can potentially be developed into such tools. The analytical work done in this study serves to investigate the current impact and impulse loading analysis capabilities in VecTor2 and VecTor3, and to identify areas where work should be focused in the future.
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Towards Simplified Tools for Analysis of Reinforced Concrete Structures Subjected to Impact and Impulsive Loading: A Preliminary InvestigationTrommels, Heather 17 July 2013 (has links)
The analysis of reinforced concrete structures under blast and impact loads is an area of research that has become increasingly relevant in recent years. Complex hydrocodes are typically used for impact analyses, although single-degree-of-freedom methods have also been developed. There are a number of disadvantages associated with both methods, and the Canadian Nuclear Safety Commission (CNSC) is looking for a tool that can be used in conjunction with hydrocodes to analyze hard and soft missile impacts, with target damage ranging from flexural cracking to perforation.
The VecTor programs, a suite of nonlinear finite element programs developed at the University of Toronto for the analysis of reinforced concrete structures, can potentially be developed into such tools. The analytical work done in this study serves to investigate the current impact and impulse loading analysis capabilities in VecTor2 and VecTor3, and to identify areas where work should be focused in the future.
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NUMERICAL AND EXPERIMENTAL STUDY OF GROUTED ROCK BOLTS AND THEIR DEFECTS USING ULTRASONIC GUIDED WAVESCui, Yan 03 May 2013 (has links)
A rock bolt installed in field has only one short exposed end on the rock surface. This condition has posed challenges in field instrumentation and made it difficult to use the ultrasonic guided wave method for rock bolt monitoring. In rock bolt laboratory tests using ultrasonic guided waves, the input and receiving transducers are typically installed at the two exposed ends of a bolt. This is suitable to laboratory conditions but not practical in the field because one of the ends of a rock bolt is embedded in the rock mass. A method needs to be found to install the receiving transducer at a suitable location in the field for receiving valid wave data.
In this thesis, a practical approach is proposed for conducting field tests with the installation of the receiving transducer on the grout surface near the exposed end of the bolt. The effects of the installation location of the receiving transducer are studied with numerical modeling. Experiments are conducted to verify the numerical modeling results. The results indicate that the data obtained from the receiving transducer installed on the grout surface at a proper location are representative and can be analyzed through the established correlations to determine the required parameters.
Previous researches have mostly focused on the feasibility of the ultrasonic guided wave method for rock bolt tests and on the behavior of ultrasonic guided waves of fully grouted rock bolts in laboratory conditions. No further study has been performed to identify the grout defects in grouted rock bolts. Adequate understanding of the behaviour of ultrasonic guided waves in rock bolts with defects is therefore prerequisite for this method to be applied in practice. This thesis investigates the effects of some typical defects (e.g., an insufficient rebar length, a missing grout at the ground end, and a void in grout) in grouted rock bolts using the developed field measurement method and numerical modeling. The results are verified by laboratory tests using the equipment set-up established in this research. The results indicate that it is practically possible to identify those grout defects using ultrasonic guided waves.
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Numerical Modeling of Thermal Enhancement of In Situ Chemical Oxidation (ISCO) and Enhanced In Situ Bioremediation (EISB)Bryck, Sean 11 February 2014 (has links)
A numerical model was utilized to assess the effects of elevated temperature on the application of in situ chemical oxidation (ISCO) and enhanced in situ bioremediation (EISB) for the subsurface remediation of trichloroethene (TCE) and tetrachloroethene (PCE). Temperature adjustment of the contaminant physicochemical properties as well as the chemical/biological reactions associated with ISCO and EISB were accounted for in the model domain. ISCO reaction rates were estimated using Arrhenius principles; microbial growth rates for EISB were estimated using non-linear fits to published literature data. The results from this study showed that temperature did provide remedial benefits to ISCO and EISB treatment during the short-term timeframe of oxidant/substrate injection. During these time periods, heated ISCO and EISB treatment exhibited greater DNAPL mass removal and mass flux reduction compared to heated abiotic dissolution. In the long term, after oxidant/substrate injection was terminated, the treatment enhancements achieved by ISCO and EISB were negated. Permeability (k) reduction due to rind formation (ISCO) and bioclogging (EISB) inhibited DNAPL dissolution and contributed to greater dissolution tailing effects. Tailing effects caused by ISCO were more severe compared to EISB since rind formation contributed to permanent k reduction; partial k recovery was observed in the EISB scenarios due to biomass decay. Even though higher temperatures were beneficial to ISCO and EISB during the short-term oxidant/substrate injection period, treatment efficacy was ultimately controlled by the detrimental by-products (rind from ISCO and biomass from EISB) formed as a result of the associative chemical/biological reactions. / Thesis (Master, Civil Engineering) -- Queen's University, 2014-02-10 18:59:23.177
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Numerical Modeling of Mobile BayMcAlpin, Tate O 15 December 2012 (has links)
A numerical model was developed for the Mobile Bay system to investigate the impacts associated with certain system alterations. The Adaptive Hydraulics (AdH) Code was used to validate the numerical model for hydrodynamics and transport. Due to the physics based nature of the AdH numerical model, the validated model could be altered to represent the plan conditions (removal of the Mobile Bay Causeway). Comparisons of the base and plan model results indicate the impacts of removing the causeway are not widespread and are primarily limited to Chocolatta Bay and the areas adjacent to the causeway. The model results suggest an increased exchange of water between Chocolatta Bay (north of the causeway) and Mobile Bay for the removed causeway configuration. Chocolatta Bay also experiences an increased inflow from the river systems which result in increased suspended sediment concentrations and sediment deposition.
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3D numerical study on droplet-solid collisions in the Leidenfrost regimeGe, Yang 24 August 2005 (has links)
No description available.
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Numerical Modeling of Electromagnetic Well-Logging SensorsLee, Hwa Ok 31 August 2010 (has links)
No description available.
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Geodynamic Modeling of Mars Constrained by InSightMurphy, Joshua 05 September 2023 (has links)
Through geodynamic modeling, I investigate how Mars could have produced the extensive volcanism required to form the Tharsis rise early in its history, as well as continue to produce small amounts of melt up to present-day, in order to account for the evidence of limited geologically recent volcanism. InSight is the first interplanetary mission dedicated primarily to the study of a planet's deep interior, and has provided useful constraints for the present structure and interior temperature of Mars. I use the results from InSight and other spacecraft missions to more accurately model Mars, and evaluate the results of my geodynamic models, so as to constrain the properties that are necessary for or consistent with both the InSight results and the volcanic history reflected on the surface. This modeling has required extensive modification to the CitcomS geodynamic code I use, the bulk of that effort being in implementing and testing the melting calculations. One of the useful constraints that would have been provided by InSight would have been ground truthing the heat flow from the interior at the landing site, and this required determining, among other quantities, the thermal conductivity of the regolith into which the heat flow probe (mole) was placed. While the mole could not penetrate to its designed depth, thus disallowing the complete heat flow measurement, the team were able to obtain the necessary data determine the thermal conductivity, and how it varies seasonally. My rapid analytical method of estimating thermal conductivity produces results that agree surprisingly well with those of the team's complex numerical model, despite the mole not meeting the assumption of a sufficiently high length to width ratio. / Doctor of Philosophy / I investigate how Mars could have produced the extensive volcanism required to form the Tharsis rise early in its history, as well as continue to produce small amounts of melt up to present-day, in order to account for the evidence of limited geologically recent volcanism. I use 3D computer models of the mantle--the solid, but slowly flowing layer that makes up the bulk of rocky planets like Earth and Mars. InSight is the first interplanetary mission dedicated to the study of a planet's deep interior, and has provided useful constraints for the present structure and interior temperature of Mars. I use the results from InSight and other spacecraft missions to more accurately model Mars, and evaluate the results of my models, so as to constrain the properties that are necessary for or consistent with both the InSight results and the volcanic history reflected on the surface. This modeling has required extensive modification to the modeling code I use, the bulk of that effort being in implementing and testing the melting calculations. One of the useful constraints that would have been provided by InSight would have been ground truthing the heat flow from the interior at the landing site, and this required determining, among other quantities, the thermal conductivity of the soil into which the heat flow probe (mole) was placed. While the mole could not penetrate to its designed depth, thus disallowing the complete heat flow measurement, the team were able to obtain the necessary data determine the thermal conductivity, and how it varies seasonally. My rapid analytical method of estimating thermal conductivity produces results that agree surprisingly well with those of the team's complex numerical model, despite the mole not meeting the assumption of a sufficiently high length to width ratio.
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