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Showing 1 to 15 of 15 for “"Shear dispersion"”.
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Shear Dispersion in Double-Porosity Systems
In this study, shear dispersion in double-porosity systems has been investigated. The major focus of this study is determination of dispersion coefficients through development of mathematical models for solute transport in a variety of coupled double-porosity systems by imposing an accurate …
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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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Mechanisms of tidal dispersion in a salt marsh estuary
Dispersion in estuaries sets the length of salinity intrusion and the horizontal mixing rate of waterborne constituents, including larvae, nutrients, sediments, and contaminants. While bulk calculations of dispersion are readily estimated using traditional field measurements, the mechanisms …
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Mechanisms of Tidal Dispersion in a Salt Marsh Estuary
Dispersion in estuaries sets the length of salinity intrusion and the horizontal mixing rate of waterborne constituents, including larvae, nutrients, sediments, and contaminants. While bulk calculations of dispersion are readily estimated using traditional field measurements, the mechanisms …
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Some problems in low Reynolds number environmental flows
… vertically across the aquifer so that there is a shear in the flow. This leads to recognition that the interface may evolve as either a rarefaction wave that grows at a rate proportional to time, a shock-like front of fixed length or a mixture of shock-like regions and rarefaction-wave-type …
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The evolution of ocean fronts in the presence of mixed layer turbulence
… by a geostrophic (or thermal wind) vertically-sheared along-front flow. However, fronts in the ocean and atmosphere co-exist with small-scale turbulence which disrupts this balance. Analytic models of fronts have often neglected the effects of small-scale turbulence; however, more recent work …
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The vertical structure of the wind-driven circulation
… is conserved, the wave enstrophy. In chapter 5 shear dispersion in an oscillatory velocity field, similar to that of an inertial oscillation, is discussed. The goal of this section is to develop intuition about the role of internal waves in horizontal ocean mixing. The problem is examined using …
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An Efficient Method for Measuring the Dispersion Coefficient in Rivers
… 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 costly and …
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Comparative analysis of Polymer Electrolyte Membrane (PEM) fuel cells
… investigating the effect of the High Share Dispersion (HSD) process on both the Nafion® and Aquivion® ionomer membrane electrode assembly (MEA). The findings in this research provides a valuable insight into the performance and durability of PFSA ionomer membrane under various application …
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Stratified and stirred: Monsoon freshwater in the Bay of Bengal
… of stratification anomalies. Comparison with shear measurements, and a numerical process study, suggest that both submesoscale sheared eddies, and thin near-inertial waves, form such layers. Fast formation timescales and large aspect ratios suggest they enhance horizontal mixing by shear …
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Modeling single-phase flow and solute transport across scales
… mixing 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 …
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Numerical simulation and modelling of the effect of film cooling on entropy noise in a stator blade row
… limited extra attenuation due to increased shear dispersion. This is found to scale with the additional mass flow rate of the coolant. <br/><br/>An analytical model has been extended to account for a film cooling flow by relaxing mass conservation across the blade row and by assuming perfect …
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Near-inertial internal Poincare waves in Lake Michigan: Seasonal variability and effects on lateral dispersion and turbulent mixing
… in the lateral direction, with vertically-sheared structures rotating clockwise at a near-inertial period. The goal of this dissertation is to investigate their seasonal variation and the potential roles on lateral dispersion and vertical mixing. ^ At this mid-lake location, the Poincaré …
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Studies of lateral dispersion in the ocean
… The first part deals with the problem of lateral dispersion due to mesoscale eddies in the open ocean, and the interaction between the mesoscale strain and horizontal diffusion on spatial scales less than 10 km. The second and major part examines lateral dispersion over the continental shelf on …
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Studies of lateral dispersion in the ocean
… The first part deals with the problem oflateral dispersion due to mesoscale eddies in the open ocean, and the interaction between the mesoscale strain and horizontal diffusion on spatial scales less than 10 km. The second and major part examines lateral dispersion over the continental shelf on …