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Showing 1 to 17 of 17 for “"RANS model"”.
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Improvement to hydrocyclone used in separating particles from produced water in the oil and gas industry.
… in the hydrocyclone; a review of the turbulence model shows that the Reynold stress model (RSM) and Large eddy simulation (LES) are the best turbulence models for the analysis. RSM was employed because of the reduced computational time when compared to the LES model. A pressure-based solver with …
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Predictive Turbulence Modeling with Bayesian Inference and Physics-Informed Machine Learning
Reynolds-Averaged Navier-Stokes (RANS) simulations are widely used for engineering design and analysis involving turbulent flows. In RANS simulations, the Reynolds stress needs closure models and the existing models have large model-form uncertainties. Therefore, the RANS simulations are known to …
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Development and Application of Hybrid Wray-Agarwal Turbulence Model and Large-Eddy Simulation
… CFD analysis, Reynolds-Averaged Navier-Stokes (RANS) equations are currently the most widely used fluid equations in the industry. RANS methods require modeling of turbulence effect (i.e. turbulence modeling) based on empirical relations and therefore often produce low accuracy results for many …
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Argon bubble transport and capture in continuous casting with an external magnetic field using GPU-based large eddy simulations
… Many defects in this process are related to the transient fluid flow in the mold region of the caster. Electromagnetic braking (EMBr) device is often used at high casting speed to modify the mold flow, reduce the surface velocity and fluctuation. This work studies the physics in continuous casting …
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Turbulent Simulations of a Buoyant Jet-in-Crossflow
… is utilized. Temperature and salinity scalar transport equations are utilized in conjunction with a linear equation of state (EOS) to obtain the density field and thus the buoyancy forcing. Comparing simulation data to experimental data of a point heat source in a stratified environment …
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Cross-shore transformation of breaking random waves in the surfzone
The transformation of breaking waves in the surfzone, including the evolution of the roller, the foamy air-water mixture on the surface of a breaking wave, and the turbulence, determines the wave-driven onshore-directed mass transport, the vertical structure of the compensating return flow …
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Quantification of Reynolds-averaged-Navier-Stokes Model Structural Hypothesis Uncertainty in Transitional Boundary Layer and Airfoil Flows
… to many Reynolds-averaged-Navier-Stokes (RANS)-based turbulence models and transition models. Although its drawback has been well acknowledged, the uncertainty it induces on RANS predictions of transitional flows has been ignored so far due to the conceptual complexity involved in the …
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Cross-shore Transformation of Breaking Random Waves in the Surfzone
The transformation of breaking waves in the surfzone, including the evolution of the roller, the foamy air-water mixture on the surface of a breaking wave, and the turbulence, determines the wave-driven onshore-directed mass transport, the vertical structure of the compensating return flow …
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Detached Eddy Simulation of Turbulent Flow and Heat Transfer in Turbine Blade Internal Cooling Ducts
Detached Eddy Simulations (DES) is a hybrid URANS-LES technique that was proposed to obtain computationally feasible solutions of high Reynolds number flows undergoing massive separation with reliable accuracy. Since its inception, DES has been applied to a wide variety of flow fields, but mostly …
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Physics-Informed, Data-Driven Framework for Model-Form Uncertainty Estimation and Reduction in RANS Simulations
… flows, the Reynolds-Averaged Navier-Stokes (RANS) equations based models are still the dominant tools for industrial applications. However, the predictive capability of RANS models is limited by potential inaccuracies driven by hypotheses in the Reynolds stress closure. With the …
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A study of flow structures in a two-stage channel using field data, a physical model and numerical modelling
… over a three year period, and numerical modelling of open channel flow. An Acoustic Doppler Current Profiler (ADCP) was used to measure the spatial distribution of velocity in two cross sections of a small meandering river (River Blackwater, Hampshire) during inbank, bankfull and overbank …
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Application of evolutionary computation to open channel flow modelling
… depth averaged Reynolds Averaged Navier Stokes (RANS) model to the flow in prismatic open channels. The RANS modeled adopted is the Shiono Knight Method (SKM) which requires three input parameters in order to provide closure, i.e. the friction factor (\(f\)), dimensionless eddy viscosity (λ) and …
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Bore Generation, Propagation, and Impact on Coastal Structures
… theoretical approaches. The theoretical models are based on three sets of equations, namely the Reynolds-Averaged Navier-Stokes (RANS) equations, the GreenNaghdi (GN) equations, and the Saint-Venant (SV) equation.<br/><br/>First, free surface flows of two and three dimensional bores …
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Towards Predictive Eddy Resolving Simulations for Gas Turbine Compressors
… for the Reynolds Averaged Navier-Stokes (RANS) based CFD methods commonly used in industry. RANS models require extensive calibration to experimental data, and thus cannot be used predictively. This thesis explores how LES can offer a more predictive alternative, by exploring the …
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The Effects of Pressure Gradient and Roughness on Pressure Fluctuations Beneath High Reynolds Number Boundary Layers
… 2D and 3D Reynolds Averaged-Navier-Stokes (RANS) computations. The effects of pressure gradient, pressure gradient history, roughness, combined roughness and pressure gradient, and combined roughness and pressure gradient history on boundary growth and the behavior of the underlying surface …
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Bulle-Effect and its implications for morphodynamics of river diversions
… Large Eddy Simulations) of flow and sediment transport for a configuration and at the scale similar to Bulle’s experiment. The simulations were conducted using the highly-scalable spectral-element based incompressible Navier-Stokes solver Nek5000, on which a Lagrangian point particle submodel …
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Machine learning for transitional and turbulent flows
L'abstract è presente nell'allegato / the abstract is in the attachment