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Showing 1 to 16 of 16 for “"Buoyancy-Driven Flow"”.
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Evaluation of RANS-Based Turbulence Models for the Propagation of Stratified Fronts in Buoyancy-Driven Flow
… safe, utilizing physical phenomena such as buoyancy and natural convection to cool the core in the event forced circulation fails. However, the widely implemented Reynolds-averaged Navier-Stokes (RANS) approach to turbulence modeling has previously shown limitations in its ability to …
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Finite element analysis of eigenvalue problems in the stability of fluid motions
… for linear and energy stability theory of buoyancy-driven flow are studied. Critical Rayleigh numbers are determined by the finite element method. The penalty method is used to approximate the incompressibility condition. We consider the stability of Boussinesq flows in a two-dimensional …
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Geochemical effects on natural convection in porous media
We describe a model of buoyancy-driven flow in a saturated reactive porous medium, the porosity and permeability of which evolve through precipitation and dissolution as a mineral is lost or gained from the pore fluid. We consider two scenarios: convection driven solely by solutally induced …
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Turbulent entrainment in flows induced by distributed buoyancy sources
Free shear and wall-bounded buoyancy-driven turbulent flows occur in both natural environments and industrial situations. In this thesis, to better understand the entrainment process within these flows, experiments and theory have been used to investigate point and distributed buoyancy sources and, …
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Submarine Groundwater Discharge in the Southern Chesapeake Bay: Constraints From Numerical Models
<p>Terrestrial and oceanic forces drive fluid flow within the coastal zone to produce submarine groundwater discharge (SGD). Groundwater flowing from the seabed serves as a significant pathway for contaminants and nutrients, producing an active biogeochemical reaction zone. In order to quantify the …
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Fluctuations, Phase Separation and Wetting Films near Liquid-Gas Critical Point
… cooling cause instabilities of the convective flow as a consequence of the expansibility divergence. In order to study boiling, fluctuation and phase separation processes near the critical point of pure fluids without the influence of the Earth's gravity, a number of experiments were performed …
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Paleohydrogeology of the Alberta Basin, Canada
… was used to simulate variable-density fluid flow, heat transport, solute transport, and sediment compaction in a tectonically evolving basin. COMPACT was modified to add effects of erosion and sediment decompaction, and dissolution of evaporites.</p> <p>Fluid flow results indicate the …
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Exploring Alternative Designs for Solar Chimneys using Computational Fluid Dynamics
Solar chimney power plants use the buoyancy-nature of heated air to harness the Sun's energy without using solar panels. The flow is driven by a pressure difference in the chimney system, so traditional chimneys are extremely tall to increase the pressure differential and the air's velocity. …
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The Application of the Solar Chimney for Ventilating Buildings
… chimney geometry was developed to predict the flow regime in the solar chimney system. To mitigate the cost and effort to use experiments to analyze building energy, a mathematical approach was considered. A relationship between small- and full-scale models was investigated using …
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Single-sided natural ventilation : design analysis and general guidelines
… to produce very complicated, fluctuating airflow patterns at the openings of buildings. An ongoing challenge in natural ventilation design is therefore the ability to control the mechanisms of wind and temperature for desirable indoor environment conditions. Understanding these effects is …
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An electrochemical investigation of the chemical diffusivity in liquid metal alloys
… of days, require long capillaries susceptible to buoyancy-driven flow from temperature fluctuations, and composition analysis must be done ex-situ as a solid. To counter all these problems, a new and novel method for measuring the chemical diffusivity of metals in liquid alloys derived from …
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Wind-Induced Exchange in Semi-Enclosed Basins
… rotation on the lateral distribution of the flow with particular emphasis on the transverse circulation. Along-basin wind-stress with no rotation caused a circulation dominated by an axially symmetric transverse structure consisting of downwind flow over the shoals and upwind flow in the …
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Dynamics of downdruaghts and cold pools: an experimental and numerical study
… to thermals rather than plumes, and their flow along the ground after impact as axisymmetric gravity currents, for example in the study performed by Rooney (2015). In this thesis both numerical and laboratory experiments have been performed by releasing finite volumes of dense fluid from …
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Numerical simulation and modeling of two-phase flows using the volume-of-fluid method
Two-phase flows are of great interest in natural and industrial applications such as cavitation, spray atomization, and bubbly flows. As a two-phase system grows in complexity, analytical approximations of fluid behavior and experimental observations become more challenging. To make the detailed …
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Numerical Analysis of Airflow and Output of Solar Chimney Power Plants
… radiation and heats the air below, whereby air flows inward towards the tower. As air exits at the top of the tower, more air is drawn below the collector repeating the process. The turbine converts pressure within the flow into power. The study investigated three validation cases to numerically …
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Computations of bubble dynamics with heat transfer
Gas-liquid flows with heat transfer play an important role in many natural and industrial processes such as combustion, petroleum refining. In particular, the heat transfer enhancement caused by air bubble motion is of practical interest in many industrial applications ranging from boiling solar …