Complex Fluid Dynamics: Chemo-Hydrodynamics Driven by Autocatalytic Reaction Fronts

This article discusses various applications of computational fluid dynamics (CFD) in the field of swimming. Using known physics and fluid dynamics relationships, CFD allows complex fluid flow regimes and geometry to be simulated within a computer environment. The ability to obtain segment-specific fluid force data within a full body stroking model provides enormous amounts of information that would be unobtainable via current empirical testing techniques. CFD software imports a realistic geometry of the athlete, generates the geometry of the surrounding water and air, and meshes these geometries to represent the athlete’s body in its surroundings. For world-class swimmers, the pursuit of a record-breaking performance at the 2016 Rio Olympics may well depend on CFD modeling and other simulations just as much as the athlete's physical ability. Experts see several applications for CFD, as engineers and academics continue their research into swimming, and coaches, athletes, and support teams prep for new competitions and championships, including the 2016 Rio Games. The growth of CFD methodology in swimming will rely on the ability to obtain easy and accurate 3-D kinematics.

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“Holographic Implementations” in the Complex Fluid Dynamics through a Fractal Paradigm

Mathematics ◽

10.3390/math9182273 ◽

2021 ◽

Vol 9 (18) ◽

pp. 2273

Author(s):

Alexandra Saviuc ◽

Manuela Gîrțu ◽

Liliana Topliceanu ◽

Tudor-Cristian Petrescu ◽

Maricel Agop

Keyword(s):

Fluid Dynamics ◽

Differential Geometry ◽

Harmonic Mapping ◽

Period Doubling ◽

Velocity Fields ◽

Hydrodynamic Type ◽

Airy Functions ◽

Structural Units ◽

Type Group ◽

Complex Fluid

Assimilating a complex fluid with a fractal object, non-differentiable behaviors in its dynamics are analyzed. Complex fluid dynamics in the form of hydrodynamic-type fractal regimes imply “holographic implementations” through velocity fields at non-differentiable scale resolution, via fractal solitons, fractal solitons–fractal kinks, and fractal minimal vortices. Complex fluid dynamics in the form of Schrödinger type fractal regimes imply “holographic implementations”, through the formalism of Airy functions of fractal type. Then, the in-phase coherence of the dynamics of the complex fluid structural units induces various operational procedures in the description of such dynamics: special cubics with SL(2R)-type group invariance, special differential geometry of Riemann type associated to such cubics, special apolar transport of cubics, special harmonic mapping principle, etc. In such a manner, a possible scenario toward chaos (a period-doubling scenario), without concluding in chaos (nonmanifest chaos), can be mimed.

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The Practical Application of CFD in the Design of Industrial Centrifugal Compressors

10.1115/imece2000-1670 ◽

2000 ◽

Author(s):

James M. Sorokes ◽

Bradley R. Hutchinson

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Fluid Flow ◽

Gas Turbine ◽

Flow Fields ◽

Practical Application ◽

Jet Engine ◽

Flow Problems ◽

Computational Fluid Dynamics Cfd ◽

Complex Fluid

Abstract In the development of industrial turbomachinery, the aerodynamic designer is faced with many complex fluid flow problems. In the mid to late 1980’s, Computational Fluid Dynamics (CFD) software was developed to assist in the solution of these flow fields. Initially applied only by high end gas turbine or jet engine designers, these sophisticated tools eventually found their way to engineers at industrial turbomachinery manufacturers. However, it has only been in the last five to ten years that industrial users have begun to make more widespread use of CFD. There are a variety of reasons for this slow adoption.

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The Fluid Dynamics of Disease Transmission

Annual Review of Fluid Mechanics ◽

10.1146/annurev-fluid-060220-113712 ◽

2021 ◽

Vol 53 (1) ◽

pp. 473-508 ◽

Cited By ~ 2

Author(s):

Lydia Bourouiba

Keyword(s):

Fluid Dynamics ◽

Disease Transmission ◽

Fluid Phase ◽

Complex Flows ◽

Fluid Physics ◽

Complex Interactions ◽

New Frontier ◽

Complex Fluid ◽

The Rich ◽

Indoor And Outdoor

For an infectious disease such as the coronavirus disease 2019 (COVID-19) to spread, contact needs to be established between an infected host and a susceptible one. In a range of populations and infectious diseases, peer-to-peer contact modes involve complex interactions of a pathogen with a fluid phase, such as isolated complex fluid droplets or a multiphase cloud of droplets. This is true for exhalations including coughs or sneezes in humans and animals, bursting bubbles leading to micron-sized droplets in a range of indoor and outdoor settings, or impacting raindrops and airborne pathogens in foliar diseases transferring pathogens from water to air via splashes. Our mechanistic understanding of how pathogens actually transfer from one host or reservoir to the next remains woefully limited, with the global consequences that we are all experiencing with the ongoing COVID-19 pandemic. This review discusses the emergent area of the fluid dynamics of disease transmission. It highlights a new frontier and the rich multiscale fluid physics, from interfacial to multiphase and complex flows, that govern contact between an infected source and a susceptible target in a range of diseases.

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The effects of a complexing agent on the transverse stability of cubic autocatalytic reaction fronts

The Journal of Chemical Physics ◽

10.1063/1.3176895 ◽

2009 ◽

Vol 131 (3) ◽

pp. 034506 ◽

Cited By ~ 3

Author(s):

J. H. Merkin

Keyword(s):

Autocatalytic Reaction ◽

Complexing Agent ◽

Reaction Fronts ◽

Transverse Stability

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Guest Editors' Preface: Discrete Models of Complex Fluid Dynamics

International Journal of Modern Physics C ◽

10.1142/s0129183197000540 ◽

1997 ◽

Vol 08 (04) ◽

pp. 637-640 ◽

Cited By ~ 4

Author(s):

Bruce M. Boghosian ◽

Francis J. Alexander ◽

Peter V. Coveney

Keyword(s):

Fluid Dynamics ◽

Discrete Models ◽

Complex Fluid

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In silico analyses of blood flow and oxygen transport in human micro-veins and valves

Clinical Hemorheology and Microcirculation ◽

10.3233/ch-211345 ◽

2022 ◽

pp. 1-16

Author(s):

Rajeeva Pandian Navaneeth Krishna ◽

Abhishek Jain

Keyword(s):

Fluid Dynamics ◽

Blood Flow ◽

Experimental Models ◽

Vortical Flow ◽

Venous Flow ◽

Venous Valves ◽

Hypoxic Environment ◽

Oxygen Gradients ◽

Direct Measurements ◽

Complex Fluid

BACKGROUND: Almost 95% of the venous valves are micron scale found in veins smaller than 300μm diameter. The fluid dynamics of blood flow and transport through these micro venous valves and their contribution to thrombosis is not yet well understood or characterized due to difficulty in making direct measurements in murine models. OBJECTIVE: The unique flow patterns that may arise in physiological and pathological non-actuating micro venous valves are predicted. METHODS: Computational fluid and transport simulations are used to model blood flow and oxygen gradients in a microfluidic vein. RESULTS: The model successfully recreates the typical non-Newtonian vortical flow within the valve cusps seen in preclinical experimental models and in clinic. The analysis further reveals variation in the vortex strengths due to temporal changes in blood flow. The cusp oxygen is typically low from the main lumen, and it is regulated by systemic venous flow. CONCLUSIONS: The analysis leads to a clinically-relevant hypothesis that micro venous valves may not create a hypoxic environment needed for endothelial inflammation, which is one of the main causes of thrombosis. However, incompetent micro venous valves are still locations for complex fluid dynamics of blood leading to low shear regions that may contribute to thrombosis through other pathways.

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