Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 93 for “"subsurface flow"”.
-
Approximate analytical solutions for modeling subsurface flow
Equations of subsurface flow of water, the Richards equation and the Boussinesq equation, have no known exact analytical solutions. Approximate analytical solutions to these equations have been developed under linearizing simplifications. In the first part of the dissertation two commonly used …
-
Effect of atmospheric variations on subsurface flow and transport
… the effect of atmospheric variations on subsurface flow and transport at the proposed high level waste repository at Yucca Mountain, Nevada. The conditions of subsurface transport were simulated with NUFT (Nonisothermal Unsaturated-Saturated Flow and Transport model) modeling software …
-
Investigating Subsurface Flow Delivery to a Small High Arctic River
Preferential flow pathways and hydraulic gradients along the hillslope-floodplain-channel continuum are dominant controls on the delivery of baseflow, stormflow and solutes to channels in temperate systems. Arctic systems are increasingly being shown to possess similar delivery mechanisms, however …
-
The Effect of Geothermal Heat Pumps on Subsurface Flow and Contaminant Transport
… their geo-environmental effects within the subsurface. This research uses FEFLOW software, to simulate heat and mass transport for a vertical closed-loop GSHP system. Steady and transient flow and heat transport results for a multiple borehole system are presented which indicate long-term …
-
An effective medium approximation and Monte Carlo simulation in subsurface flow modeling
… procedure for solving the stochastic groundwater flow problem are presented. The effective medium approximation permits one to solve the stochastic groundwater flow problem in a single run to generate the expected pressure head field. The proposed effective hydraulic conductivity expression for …
-
Hydraulic Characteristics and Nutrient Degradation Kinetics of a Horizontally Orientated Subsurface Flow Biofilter
… solutions such as horizontally orientated subsurface flow biofilters are a potential suitable remediation measure, as they are cost-effective, scalable and easy to maintain. However, the variable nutrient levels in surface waters affected by informal settlements pose a challenge to …
-
Investigation of Partial Contributing Areas in Watersheds With a Conjunctive Surface Subsurface Flow Model
… developed a physically based conjunctive flow model (CFM) coupling two-dimensional surface three-dimensional subsurface transport to simulate the total runoff in watersheds. In conjunction with the CFM, an overland flow-tracking program (OFTP) was developed to compute the PCA under the …
-
Performance Evaluation of the Town of Monterery Wastewater Treatment Plant Utilizing Subsurface Flow Constructed Wetlands
… the performance of the Monterey WWTP utilizing subsurface flow (SF) constructed wetlands. Previous work with SF wetlands has demonstrated adequate, but variable removal of organic matter, suspended solids, and nitrogen. Few research studies have observed the generation of compounds in the …
-
Geochemical characterization and subsurface flow path evaluation of mine drainage sources in the Chalk Creek district, Colorado
Includes bibliographical references (pages 41-43).
-
The Hillslope Hydrology of a Mountain Pasture: The Influence of Subsurface Flow on Nitrate and Ammonium Transport
… enter aquatic ecosystems through surface and subsurface hydrological transport that drain agricultural watersheds. The over-abundance of nitrogen within these watersheds is easily transported to receiving stream and rivers, and result in aquatic ecosystem degradation. In response to the …
-
Modeling the Impacts of Land Use Activities on the Subsurface Flow Regime of the Upper Roanoke River Watershed
… the impact of land use activities on the subsurface flow regime in the Upper Roanoke River Watershed in Virginia to determine the impacts of land use change on the subsurface flow system, and to provide a tool for future management decisions. Land use activities can impact the groundwater …
-
Effect of depth and plants on pollutant removal in horizontal subsurface flow constructed wetlands and their application in Ethiopia
… Verhalten horizontal durchflossener Bodenfilter (subsurface flow-constructed wetlands, HSSFCW) in Abhängigkeit von ihrer Beettiefe und Bepflanzung. Die betreffenden Untersuchungen erfolgten in Langenreichenbach (Deutschland) von September 2010 bis September 2012 und in Arba Minch (Äthiopien) von …
-
Phosphorus Retention and Fractionation in Masonry Sand and Light Weight Expanded Shale Used as Substrate in a Subsurface Flow Wetland
… (P) removal. The P retention effectiveness of subsurface wetlands can be improved by using appropriate substrates. The objectives of this study were to: (i) use sorption isotherms to estimate the P sorption capacity of the two materials, masonry sand and light weight expanded shale; (ii) …
-
Turbulent interactions between stream flow and near-subsurface flow: a laboratory approach using particle image velocimetry and refractive index matching
Turbulent flow over a rough, porous gravel bed (particle diameter, D = 1.27 cm) is investigated in the laboratory using particle image velocimetry (PIV) and refractive index matching (RIM). This combination allows for detailed examination of flow fields both in the near-bed region and within the …
-
Water flow paths in soils of an undisturbed and landslide affected mature montane rainforest in South Ecuador
… previous hydrological studies concerning water flow paths in tropical montane rainforest is small. However, due to the increasing pressure of deforestation and land use change comprehensive knowledge of these natural ecosystems is needed if sustainable land use strategies should keep negative …
Page 1 of 5