In Situ Visualization and Analysis to Design Large Scale Experiments in Computational Fluid Dynamics

Computational Fluid Dynamics is currently used to design and improve the hydraulic properties of biomedical devices, wherein the large scale blood circulation needs to be simulated by accounting for the mechanical response of RBCs at the mesoscale.

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In-situ assessment of biofilm formation in submerged membrane system using optical coherence tomography and computational fluid dynamics

Journal of Membrane Science ◽

10.1016/j.memsci.2016.09.004 ◽

2017 ◽

Vol 521 ◽

pp. 84-94 ◽

Cited By ~ 40

Author(s):

Luca Fortunato ◽

Adnan Qamar ◽

Yiran Wang ◽

Sanghyun Jeong ◽

TorOve Leiknes

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Optical Coherence Tomography ◽

Biofilm Formation ◽

Membrane System ◽

Optical Coherence ◽

In Situ Assessment

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Flow Visualization of Spinning and Nonspinning Soccer Balls Using Computational Fluid Dynamics

Applied Sciences ◽

10.3390/app10134543 ◽

2020 ◽

Vol 10 (13) ◽

pp. 4543 ◽

Cited By ~ 1

Author(s):

Takeshi Asai ◽

Yasumi Nakanishi ◽

Nakaba Akiyama ◽

Sungchan Hong

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Lattice Boltzmann Method ◽

Vortex Structure ◽

Lattice Boltzmann ◽

Large Scale ◽

Vortex Pair ◽

Vortex Structures ◽

Soccer Ball ◽

Boltzmann Method

Various studies have been conducted on the aerodynamic characteristics of nonspinning and spinning soccer balls. However, the vortex structures in the wake of the balls are almost unknown. One of the main computational fluid dynamics methods used for the analysis of vortex structures is the lattice Boltzmann method as it facilitates high-precision analysis. Studies to elucidate the dominant vortex structure are important because curled shots and passes involving spinning balls are frequently used in actual soccer games. In this study, we identify the large-scale dominant vortex structure of a soccer ball and investigate the stability of the structure using the lattice Boltzmann method, wind tunnel tests, and free-flight experiments. One of the dominant vortex structures in the wake of both nonspinning and spinning balls is a large-scale counter-rotating vortex pair. The side force acting on a spinning ball stabilizes when the fluctuation of the separation points of the ball is suppressed by the rotation of the ball. Thus, although a spinning soccer ball is deflected by the Magnus effect, its trajectory is regular and stable, suggesting that a spinning ball can be aimed accurately at the outset of its course.

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Detailed Analysis of the Wake Structure of a Straight-Blade H-Darrieus Wind Turbine by Means of Wind Tunnel Experiments and Computational Fluid Dynamics Simulations

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4037906 ◽

2017 ◽

Vol 140 (3) ◽

Cited By ~ 14

Author(s):

Alessandro Bianchini ◽

Francesco Balduzzi ◽

Giovanni Ferrara ◽

Lorenzo Ferrari ◽

Giacomo Persico ◽

...

Keyword(s):

Fluid Dynamics ◽

Experimental Data ◽

Computational Fluid Dynamics ◽

Wind Tunnel ◽

Wind Turbines ◽

Large Scale ◽

Vertical Axis ◽

Performance Estimation ◽

Small Scale ◽

Dynamics Simulations

Darrieus vertical axis wind turbines (VAWTs) have been recently identified as the most promising solution for new types of applications, such as small-scale installations in complex terrains or offshore large floating platforms. To improve their efficiencies further and make them competitive with those of conventional horizontal axis wind turbines, a more in depth understanding of the physical phenomena that govern the aerodynamics past a rotating Darrieus turbine is needed. Within this context, computational fluid dynamics (CFD) can play a fundamental role, since it represents the only model able to provide a detailed and comprehensive representation of the flow. Due to the complexity of similar simulations, however, the possibility of having reliable and detailed experimental data to be used as validation test cases is pivotal to tune the numerical tools. In this study, a two-dimensional (2D) unsteady Reynolds-averaged Navier–Stokes (U-RANS) computational model was applied to analyze the wake characteristics on the midplane of a small-size H-shaped Darrieus VAWT. The turbine was tested in a large-scale, open-jet wind tunnel, including both performance and wake measurements. Thanks to the availability of such a unique set of experimental data, systematic comparisons between simulations and experiments were carried out for analyzing the structure of the wake and correlating the main macrostructures of the flow to the local aerodynamic features of the airfoils in cycloidal motion. In general, good agreement on the turbine performance estimation was constantly appreciated.

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In situ adaptive tabulation (ISAT) to accelerate transient computational fluid dynamics with complex heterogeneous chemical kinetics

Computers & Chemical Engineering ◽

10.1016/j.compchemeng.2015.08.020 ◽

2016 ◽

Vol 84 ◽

pp. 36-42 ◽

Cited By ~ 11

Author(s):

Justin M. Blasi ◽

Robert J. Kee

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Chemical Kinetics ◽

Heterogeneous Chemical ◽

In Situ Adaptive Tabulation

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Computational Modelling of Self-Excited Combustion Instabilities

Volume 2: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations ◽

10.1115/2000-gt-0104 ◽

2000 ◽

Cited By ~ 4

Author(s):

Steve J. Brookes ◽

R. Stewart Cant ◽

Iain D. J. Dupere ◽

Ann P. Dowling

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Heat Release ◽

Large Scale ◽

Computational Modelling ◽

Combustion Efficiency ◽

Design Tool ◽

Premixed Combustion ◽

Combustion Instabilities ◽

Combustion Systems

It is well known that lean premixed combustion systems potentially offer better emissions performance than conventional non-premixed designs. However, premixed combustion systems are more susceptible to combustion instabilities than non-premixed systems. Combustion instabilities (large-scale oscillations in heat release and pressure) have a deleterious effect on equipment, and also tend to decrease combustion efficiency. Designing out combustion instabilities is a difficult process and, particularly if many large-scale experiments are required, also very costly. Computational fluid dynamics (CFD) is now an established design tool in many areas of gas turbine design. However, its accuracy in the prediction of combustion instabilities is not yet proven. Unsteady heat release will generally be coupled to unsteady flow conditions within the combustor. In principle, computational fluid dynamics should be capable of modelling this coupled process. The present work assesses the ability of CFD to model self-excited combustion instabilities occurring within a model combustor. The accuracy of CFD in predicting both the onset and the nature of the instability is reported.

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Surface wind flow modelling on Mars using Computational Fluid Dynamics

10.5194/egusphere-egu2020-335 ◽

2020 ◽

Author(s):

Richard Love ◽

Derek. W. T. Jackson ◽

J. Andrew G. Cooper ◽

Jean-Philippe Avouac ◽

Thomas A. G. Smyth ◽

...

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Surface Wind ◽

Wind Flow ◽

Topographic Effects ◽

Initial State ◽

Global Circulation Models ◽

In Situ Data ◽

Wind Regimes

Wind flows on Mars are the dominant contemporary force driving sediment transport and associated morphological change on the planet&#8217;s dune fields. To fully understand the atmospheric &#8211; surface interactions occurring on the dunes, investigations need to be conducted at appropriate length scales (at or below that of any landform features being examined).The spatial resolution of Martian Global Circulation Models (GCMs) is too low to adequately understand atmospheric-surface processes. Nevertheless, they can be utilised to establish initial state and boundary conditions for finer-scale simulations. Mesoscale atmospheric models have been used before to understand forcing and modification of entire dune fields. However, their resolution is still too coarse to fully understand interactions between the boundary layer and the surface. This study aims to examine and improve our understanding of local-scale processes using microscale (e.g., 1.5m cell spacing) airflow modelling to better investigate localised topographic effects on wind velocity and associated aeolian geomorphology.Toward these aims, this study will simulate microscale wind flow using computational fluid dynamics software (OpenFOAM) at a series of sites containing a variety of topographies and wind regimes. A Mars GCM will provide input for baseline mesoscale modelling runs, the output of which will then be used as input for microscale airflow modelling. The sites used for the study will have excellent orbital, or preferentially, in situ data coverage. Detailed HiRISE imagery will provide high-resolution Digital Terrain Models (DTMs) which will be used by the OpenFOAM simulations. Results from model simulations will be evaluated/validated using both in situ data and geomorphic analysis of imagery.

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