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Showing 1 to 20 of 22 for “"Longitudinal dispersion"”.
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Longitudinal dispersion in vegetated flow
… flow structure, and thus both advection and dispersion. Accurate prediction of the fate and transport of nutrients, microbes, dissolved oxygen and other scalars depends on our ability to quantify vegetative impacts. In this thesis, the focus is on longitudinal dispersion, which traditionally …
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Longitudinal dispersion in non-uniform porous media
Thesis: M.S., Massachusetts Institute of Technology, Department of Civil Engineering, 1964
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Experiment study of the influence of vegetation on longitudinal dispersion
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1995.
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Heat Transfer via the Wall--and Longitudinal Dispersion Between Alternate Pulses of Warm and Cool Air Flowing in a Pipe
Made available in DSpace on 2014-12-10T22:48:25Z (GMT). No. of bitstreams: 1 7500378.pdf: 3427316 bytes, checksum: b2737bd1c1a5ab7e237b86300dd69d69 (MD5) Previous issue date: 1974
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LONGITUDINAL SOLUTE TRANSPORT IN OPEN-CHANNEL FLOW - A Numerical Simulation Study on Longitudinal Dispersion, Surface Storage Effects, Transverse Mixing, Uncertainties and Parameter-Transferring Problems
The longitudinal solute transport modeling is critical in river and stream water quality management, control, and the mitigation of hazardous riverine spills. One of the widely used "deadzone" model is the transient storage model (TSM). TSM is a significant improvement over the advection-dispersion …
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Laminar and turbulent dispersion of miscible fluids in porous media
The phenomenon of longitudinal dispersion in the flow of miscible fluids through porous media was studied in this investigation. The relationship between the longitudinal dispersion coefficient and the average pore velocity was found experimentally for the three regimes of fluid flow in a porous …
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Field and laboratory observations of small-scale dispersion in wetlands
Estimating longitudinal dispersion in wetlands is a necessary first step in predicting the behavior of dissolved species and suspended particles. However, many processes are involved, and they can interact in nonlinear ways. Relevant processes include turbulent diffusion, which describes net solute …
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The Effects of Varying Fresh Water Discharge on Dispersion in an Estuarine Hydraulic Model of the Lafayette River, Norfolk, Virginia
… discharge on mixing parameters including the longitudinal dispersion coefficient (E).</p> <p>The model generated a tide of constant range and period. Batch releases of Rhodamine WT dye were made in the model and sampled throughout the river for ten tidal cycles. Samples were taken …
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Dispersão longitudinal em rios: desempenho de Métodos de previsão e de traçadores fluorescentes
This thesis presents the determination of the longitudinal dispersion coefficient (DL) in rivers, applying empirical equations, analytical methods and methods that use results obtained from tracer experiments. The values of DL were calculated under different flow conditions of the Paraíba do Sul …
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Quantitative Measurement of Velocity and Dispersion via Magnetic Resonance Imaging
… velocity fields in more general swirling flows. Longitudinal dispersion measurements in the packed bed and partitioned pipe mixer corroborated previous measurements and facilitated the development of functional relationships between interstitial space flow and mixing behavior.
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Lattice Boltzmann Study of the Interstitial Hydrodynamics and Dispersion in Steady Inertial Flows in Large Randomly Packed Beds
… investigation of interstitial fluid dynamics and dispersion in two-dimensional packed beds in the inertial regime (post-Stokes flow) is undertaken starting from first principles. Long exponential tails are found in the histograms of both interstitial velocity components for low porosity packed …
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Analysis of Flow and Transport in Refractive Index Matched Porous Media
… the first simultaneous estimation of the longitudinal and both transversal hydrodynamic dispersion coefficients. Whereas for the longitudinal dispersion a previously known power-law could be confirmed, the significantly different behavior of the transversal dispersion in vertical and …
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An Efficient Method for Measuring the Dispersion Coefficient in Rivers
… Doppler current profiler (ADCP) to estimate the longitudinal dispersion coefficient K is evaluated. If shear dispersion controls mixing, the dispersion coefficient can be estimated from a theoretical formula involving velocity measurements in a cross section. K has typically been measured by …
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Modeling single-phase flow and solute transport across scales
… within pores (large void volumes), and b) shear dispersion within throats (narrow constrictions connecting the pores), which are shown to have a substantial impact on transverse and longitudinal dispersion coefficients at the macro scale. The models are verified with high-resolution pore-scale …
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Modeling temporal and spatial variations in dissolved oxygen in Amite River
… hyporheic exchange can reduce K2 by 30% while longitudinal dispersion increases K2 by 50%. VART-DOS model is developed for simulation of temporal variations in DO particularly due to sediment resuspension effect during high flow. Application results of VART-DOS model to the Amite River in …
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Some geological implications of the flow of clay-water mixtures
… affected by the eddies and leads to significant longitudinal dispersion in the flow. The implications of the modelling for determining the residence time distribution of the fluid in the plume is discussed.
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Enhanced gas recovery and storage: the role of N2 during natural gas displacement by CO2 flooding in sandstone rocks
… results indicated that the coefficient of longitudinal dispersion decline with raises in booster gas volume, hence the higher the amount of booster the less the dispersion of CO2 into CH4. The higher the booster volume the higher the sequestered CO2, especially at higher CO2 injection rates …
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Comparison of non-reactive solute transport models for the evaluation of fluid flow in leaching beds
… models selected were the advection-dispersion (AD), piston exchange (PE), piston exchange-diffusion variant (PE-D) and piston dispersion and exchange (PDE) models. A novel model formulation called the piston dispersion and exchange-diffusion variant (PDE-D) model was also coded and …
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Modelling dispersion and mixing in geophysical flows
… The problems considered in this work include dispersion in flows through heterogeneous porous rocks, turbulent mixing in the surface layer of the ocean, and mixing in turbulent starting plumes. In chapters 2, 3 and 4, we study the longitudinal dispersion of a passive tracer by a …
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Investigation of a stochastic solute transport model and development of inverse methods in hydrogeology
… capable of simulating the scale effect of solute dispersion and, to some extent, they agree with the past literature. In second part, we develop two different inverse methods to estimate the hydrogeologic parameters. In the first inverse method, the maximum likelihood approach is used to estimate …
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