This master thesis presents a novel methodology for the  development of simulation models  for hydraulic pumps and motors. In this work, a generic simulation model capable of representing multiple axial piston machines is presented, implemented and validated. Validation of the developed generic simulation model is done by comparing the results from the simulation model with experimental measurements. The development of the generic model is done using AMESim. Today simulation models are an integral part of any development process concerning hydraulic machines. An improved methodology for developing these simulation models will affect both the development cost and time in a positive manner. Traditionally, specific simulation models dedicated to a certain pump or motor are created. This implies that a complete rethinking of the model structure has to be done when modeling a new pump or motor. Therefore when dealing with a large number of pumps and motors, this traditional way of model development could lead to large development time and cost. This thesis work presents a unique way of simulation model development where a single model could represent multiple pumps and motors resulting in lower development time and cost. An automated routine for simulation model creation is developed and implemented. This routine uses the generic simulation model as a template to automatically create simulation models requested by the user. For this purpose a user interface has been created through the use of Visual Basic scripting. This interface communicates with the generic simulation model allowing the user to either change it parametrically or completely transform it into another pump or motor. To determine the level of accuracy offered by the generic simulation model, simulation results are compared with experimental data. Moreover, an optimization routine to automatically fine tune the simulation model is also presented.

The effective and efficient remediation of contaminated groundwater sites requires site specific information regarding the physical, chemical and biological properties of the aquifer. Building on the dipole flow test (DFT) and the dipole flow and tracer test (DFTT), the dipole flow and reactive tracer test (DFRTT) has been proposed as an alternative to current aquifer parameter estimation methods. A steady-state dipole flow field is created by circulating groundwater between chambers isolated by the dipole tool. A tracer is released into the injection chamber and the breakthrough curve at the extraction chamber is interpreted with the DFRTT specific model. The overall goal of this thesis was to demonstrate the ability of a prototype dipole system to produce tracer BTCs in conventional wells installed in an unconfined sandy aquifer. The Waterloo dipole probe was constructed and field tested at CFB Borden. DFTs conducted along the length of the screen of non-filter packed monitoring wells provided similar estimates of radial hydraulic conductivity (Kr) to slug tests and literature values. The geometric mean Kr estimated in the filter packed wells was approximately an order of magnitude greater than the mean Kr estimate for the non-filter packed wells due to short-circuiting through the filter pack. A total of 46 DFTTs were completed in the monitoring wells at CFB Borden to investigate the properties of the BTCs. The shape of the BTC for a conservative tracer is affected by test set up parameters, well construction, and aquifer formation properties. The BTCs from the DFTTs completed in the non-filter pack monitoring wells were categorized into four “type curves” based on the BTC properties. The differences between the type curves were largely defined by the ratio of K between the skin zone and the aquifer (Ks/Kr). Now that a series of DFTT BTCs have been generated, the DFRTT model will be used to estimate the aquifer parameters. To continue the work outlined in this thesis, DFRTTs are planned for well-documented contaminated sites.

The purpose of this study was to evaluate the effectiveness of traditional hydrogeologic characterization approaches in a highly heterogeneous glaciofluvial aquifer at the North Campus Research Site (NCRS), situated on the University of Waterloo campus. Continuous soil cores to a depth of approximately 18 m were collected during the installation of the CMT monitoring wells and the multi-screen pumping well. K estimates were obtained for the core by obtaining 471 samples and testing them with a falling head permeameter, as well as by utilizing empirical equations developed to estimate K. A geostatistical analysis performed on the K datasets yielded strongly heterogeneous kriged K fields for the site. K and Ss were also estimated via type curve analysis of slug and pumping test data collected at the site. The various K and Ss estimates were then evaluated by simulating the transient drawdown data using a 3D forward numerical model constructed using Hydrogeosphere (Therrien et al., 2005). Results showed that, while drawdown predictions generally improved as more complexity was introduced into the model, the ability to make accurate drawdown predictions at all of the CMT ports was inconsistent. These results suggest that new techniques may be required to accurately capture subsurface heterogeneity for improved predictions of flow in similar systems.

The underlying objective of this research is to improve the overall understanding of how spatial and temporal variability in macroporosity and soil hydraulic properties in the shallow subsurface influence the long term mobility of agricultural nutrients, and specifically the movement of liquid swine manure, in macroporous, tile drained soils. The principal motivation for the work was to provide insight into dynamic nutrient mobility in this type of agricultural environment in order to guide both the efficiency and environmental sustainability of nutrient management practices. The results of this work facilitate the advancement of our conceptual understanding and our ability to simulate preferential flow and transport in structured agricultural soils that are subject to seasonal hydrologic patterns similar to those found in the humid continental climate of southwestern Ontario

This thesis describes a numerical modelling methodology to interpret dynamic fluctuations in pore-pressures to isolate the effects of loading associated with changes in total soil moisture (site water balance) alone. The methodology is required to enhance the data-interpretation and performance-assessment for potential applications of a novel piezometer-based, large-scale, geological weighing lysimeter. This interpretative methodology is based on a method of superimposing computer-based numerical analyses of independent causes of pore-pressure transients to separate the different pore-pressure responses. Finite element coupled load-deformation and seepage numerical models were used to simulate field-observed piezometric responses to water table fluctuations and loading induced by surface water balance (using meteorological data).<p> Transient pore-pressures in a deep clay-till-aquitard arising from variations in the water table within a surface-aquifer were modelled and removed from the measured pore-pressure record (corrected for earth tide and barometric effects) to isolate and identify pore-pressure fluctuations arising from loading associated with site water balance. These estimates were compared to simulated pore-pressure responses to an independently measured water balance using meteorological instrumentation. The simulations and observations of the pore-pressure responses to surface water balance were in good agreement over the dry years of a 9-year period. Some periods of significant differences did occur during wet years in which runoff, which is not accounted for in the current analyses, may have occurred.<p> The identification of pore-pressure response to total soil moisture loading using the developed numerical modelling methodology enhances the potential for the deployment of the piezometer-based geological weighing lysimeter for different applications which include real-time monitoring of site water balance and hydrological events such as precipitation and flooding. Interestingly, the disparity occurring during the wet years even suggests the potential to adapt the method to monitor runoff (net lateral flow).<p> The methodology also demonstrated the capability to accurately estimate in situ elastic and hydraulic parameters. Calibration of the model yielded equivalent properties of the aquitard (hydraulic conductivity, Kv, of 2.1E-5 m/day and specific storage, Ss, of 1.36E-5 /m) for a Skemptons B-bar coefficient of 0.91 for an assumed porosity of 0.26. Sensitivity tests also provided insight into the consolidation and pressure propagation (swelling) behaviour of the aquitard under parametric variations. The parameters obtained are consistent with range of values reported for glacial clay till soil. Therefore, this work also provides a unique case history of a method for determining, large scale, in situ material properties for geo-engineers and scientists to explore by simply using piezometric and meteorological data.

Mit landschaftsplanerischen und wasserbaulichen Maßnahmen soll die Kleine Spree gemäß EG-WRRL einen guten Zustand erreichen. Das 40 km lange Nebengewässer der Spree ist stark vom Braunkohlenbergbau beeinflusst. Der Bericht beschreibt und bewertet den Ist-Zustand der Kleinen Spree, analysiert die Defizite und leitet die Maßnahmen für einen guten ökologischen Zustand ab. Für die Gewässerabschnitte wurden Pläne zur Renaturierung im Maßstab von 1:10.000 erstellt. Sie basieren auf dem Strahlquellen- und Trittsteinprinzip, bei dem ökologisch gute und sehr gute Abschnitte so im Gewässerverlauf platziert werden, dass die Strahlwirkung das gesamte Gewässer umfasst.

This thesis research consists of two separate studies. The first study presents the assessment and representation of the effects of soil macropores on the soil hydraulic properties in land surface models for more accurate simulations of soil moisture and surface hydrology. Hydraulic properties determine the soil water content and its transport in the soil. They are provided in most current climate models as empirical formulas by functions of the soil texture. Such is not realistic if the soil contains a substantial amount of macropores. A two-mode soil pore size distribution is incorporated into a land surface model and tested using an observational dataset at a tropical forest site with aggregated soils. The result showed that the existence of macropores greatly affects the estimation of hydraulic properties. Their influence can be included in land models by adding a second function to the pore-size distribution. A practical hydraulic scheme with macropore considerations was proposed given that the existing schemes are not applicable for large-scale simulations. The developed scheme was based on the physical attributes of the water in soil capillary pores and the statistics of several global soil databases. The preliminary test showed that it captures part of soil macropore hydraulic features without sacrificing the estimation accuracy of hydraulic properties of water in soil matrix. The second study presents the development of an integrated land/ecosystem model by combining the advanced features of a biophysically based land model, the Community Land Model, and an ecosystem biochemical model. The results from tests of the integrated model at four forest sites showed that the model reasonably captures the seasonal and interannual dynamics of leaf area index and leaf nitrogen control on carbon assimilation across different environments. With being coupled to an atmospheric general circulation model (AGCM), the integrated model showed a strong ability to simulate terrestrial ecosystem carbon fluxes together with heat and water fluxes. Its simulated land surface physical variables are reasonable in both geographic distribution and temporal variation with considering the interactive vegetation parameters.

In the study, an innovative method is developed in 2-D wave flume tests to explore how much sand is set in motion by waves, and how wave-moved sediment is related to wave properties. Wave conditions on an initial sea bed slopes with grain size of about 0.1mm are varying during the experiments. Three initial bottom slopes of 1/30, 1/45, and 1/60 are analyzed in the study. The total number of waves acting is about 39,600 for each wave condition. The accumulated time of generated waves during the study is more than 1,280 hours; this is equivalent to about 2.45 million waves. The dark sands, along the observing window of the wave tank, of an initial sea bed are replaced by a slice column of white sands. The mixing caused by the waves moved dark and white sands together which generates a layer of grey sands that marks the interface of moved and unmoved white sands on the window. In some cases, three additional white sand columns are merged into the dark sand body perpendicular to the window to verify the uniformity of the moved layer in the wave crest direction. The quantity of the moved sediment is then computed and the wave-moved sediment by each wave is evaluated. Results show that the wave-moved sediment by each wave is linearly correlated to the wave breaking induced turbulent eddy viscosity, based on Prandtls mixing length model. The corresponding proportional coefficient reaches an asymptotic value as the number of acting waves is more than about 10,000. A Similar trend, but more diverse, is found when the wave-moved sediment is related to a movable parameter defined from the Shields number in which the Komars relation of bottom friction and slope is applied. However, the results indicate that the wave-moved sediment does not linearly correlate with the breaking wave power as proposed by most previous studies.

Two new fuel assembly designs for light water reactors using advanced mixed-oxide fuels have been proposed to reduce the radiotoxicity of used nuclear fuel discharged from nuclear power plants. The research efforts of this thesis are the first to consider the effects of burnup on advanced mixed-oxide fuel assembly performance and thermal safety margin over an assembly?s expected operational burnup lifetime. In order to accomplish this, a new burnup-dependent thermal-hydraulic analysis methodology has been developed. The new methodology models many of the effects of burnup on an assembly design by including burnup-dependent variations in fuel pin relative power from neutronic calculations, assembly power reductions due to fissile content depletion and core reshuffling, and fuel material thermal-physical properties. Additionally, a text-based coupling method is developed to facilitate the exchange of information between the neutronic code DRAGON and thermal-hydraulic code VIPRE-01. The new methodology effectively covers the entire assembly burnup lifetime and evaluates the thermal-hydraulic performance against ANS Condition I, II, and III events with respect to the minimum departure from nucleate boiling ratio, peak cladding temperatures, and fuel centerline temperatures. A comprehensive literature survey on the thermal conductivity of posed fuel materials with burnup-dependence has been carried out to model the advanced materials in the thermal-hydraulic code VIPRE-01. Where documented conductivity values are not available, a simplified method for estimating the thermal conductivity has been developed. The new thermal conductivity models are based on established FRAPCON-3 fuel property models used in the nuclear industry, with small adjustments having been made to account for actinide additions. Steady-state and transient thermal-hydraulic analyses are performed with VIPRE- 01 for a reference UO2 assembly design, and two advanced mixed-oxide fuel assembly designs using the new burnup-dependent thermal-hydraulic analysis methodology. All three designs maintain a sufficiently large thermal margin with respect to the minimum departure from nucleate boiling ratio, and maximum cladding and fuel temperatures during partial and complete loss-of-flow accident scenarios. The presence of a thin (Am,Zr)O2 outer layer on the fuel pellet in the two advanced mixed-oxide fuel assembly designs increases maximum fuel temperatures during transient conditions, but does not otherwise greatly compromise the thermal margin of the new designs.

The conductivity of acid-etched fractures highly depends on spaces along the fracture created by uneven etching of the fracture walls remaining open after fracture closure. Formation heterogeneities such as variations of mineralogy and permeability result in channels that contribute significantly to the fracture conductivity. Current numerical simulators or empirical correlations do not account for this channeling characteristic because of the scale limitations. The purpose of this study is to develop new correlations for conductivity of acid-etched fracturing at the intermediate scale. The new correlations close the gap between laboratory scale measurements and macro scale acid fracture models. Beginning with acid-etched fracture width profiles and conductivity at zero closure stress obtained by the previous work, I modeled the deformation of the fracture surfaces as closure stress is applied to the fracture. At any cross-section along the fracture, I approximated the fracture shape as being a series of elliptical openings. With the assumption of elastic behavior for the rock, the numerical simulation presents how many elliptical openings remain open and their sizes as a function of the applied stress. The sections of the fracture that are closed are assigned a conductivity because of small-scale roughness features using a correlation obtained from laboratory measurements of acid fracture conductivity as a function of closure stress. The overall conductivity of the fracture is then obtained by numerically modeling the flow through this heterogeneous system. The statistical parameters of permeability distribution and the mineralogy distribution, and Young’s modulus are the primary aspects that affect the overall conductivity in acid-etched fracturing. A large number of deep, narrow channels through the entire fracture leads to high conductivity when the rock is strong enough to resist closure stress effectively. Based on extensive numerical experiments, I developed the new correlations in three categories to predict the fracture conductivity after closure. Essentially, they are the exponential functions that incorporate the influential parameters. Combined with the correlations for conductivity at zero closure stress from previous work, the new correlations are applicable to a wide range of situations.