Letteratura scientifica selezionata sul tema "Emergent hydrodynamics"
Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili
Consulta la lista di attuali articoli, libri, tesi, atti di convegni e altre fonti scientifiche attinenti al tema "Emergent hydrodynamics".
Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.
Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.
Articoli di riviste sul tema "Emergent hydrodynamics"
1
Joshi, M. K., F. Kranzl, A. Schuckert, I. Lovas, C. Maier, R. Blatt, M. Knap e C. F. Roos. "Observing emergent hydrodynamics in a long-range quantum magnet". Science 376, n. 6594 (13 maggio 2022): 720–24. http://dx.doi.org/10.1126/science.abk2400.
Testo completoAbstract (sommario):
Identifying universal properties of nonequilibrium quantum states is a major challenge in modern physics. A fascinating prediction is that classical hydrodynamics emerges universally in the evolution of any interacting quantum system. We experimentally probed the quantum dynamics of 51 individually controlled ions, realizing a long-range interacting spin chain. By measuring space-time–resolved correlation functions in an infinite temperature state, we observed a whole family of hydrodynamic universality classes, ranging from normal diffusion to anomalous superdiffusion, that are described by Lévy flights. We extracted the transport coefficients of the hydrodynamic theory, reflecting the microscopic properties of the system. Our observations demonstrate the potential for engineered quantum systems to provide key insights into universal properties of nonequilibrium states of quantum matter.
2
Wang, Yuting, Huilan Zhang, Pingping Yang e Yunqi Wang. "Experimental Study of Overland Flow through Rigid Emergent Vegetation with Different Densities and Location Arrangements". Water 10, n. 11 (12 novembre 2018): 1638. http://dx.doi.org/10.3390/w10111638.
Testo completoAbstract (sommario):
The effect of vegetation density on overland flow dynamics has been extensively studied, yet fewer investigations have focused on vegetation arrangements with different densities and position features. Flume experiments were conducted to investigate the hydrodynamics of flow through rigid emergent vegetation arranged in combinations with three densities (Dense, Middle, and Sparse) and three positions (summit, backslope, and footslope). This study focused on how spatial variations regulated hydrodynamic parameters from two dimensions: direction along the slope and water depth. The total hydrodynamic parameters of bare slopes were significantly different from those of vegetated slopes. The relationship between Re and f illustrated that Re was not a unique predictor of hydraulic roughness on vegetated slopes. In the slope direction, all hydrodynamic parameters on vegetated slopes exhibited fluctuating downward/upward trends due to the clocking effect before the vegetated area and the rapid conveyance effect in the vegetated area, whereas constant values were observed on bare slopes. The performance of hydrodynamics parameters suggested that the dense rearward arrangement (SMD) was the optimal vegetation pattern to regulate flow conditions. Specifically, the vertical profiles of the velocity and turbulence features of the SMD arrangement at different sections demonstrated the significant role of vegetation density in identifying the velocity layers along the water depth. The maximum velocity and Reynolds Stress Number (RSN) indicated the position where local scour was most likely to occur, which would improve our basic understanding of the mechanisms underlying hydraulic and soil erosion processes.
3
Manna, Raj Kumar, e P. B. Sunil Kumar. "Emergent topological phenomena in active polymeric fluids". Soft Matter 15, n. 3 (2019): 477–86. http://dx.doi.org/10.1039/c8sm01981a.
Testo completo
4
Zhang, Bokai, Premkumar Leishangthem, Yang Ding e Xinliang Xu. "An effective and efficient model of the near-field hydrodynamic interactions for active suspensions of bacteria". Proceedings of the National Academy of Sciences 118, n. 28 (6 luglio 2021): e2100145118. http://dx.doi.org/10.1073/pnas.2100145118.
Testo completoAbstract (sommario):
Near-field hydrodynamic interactions in active fluids are essential to determine many important emergent behaviors observed, but have not been successfully modeled so far. In this work, we propose an effective model capturing the essence of the near-field hydrodynamic interactions through a tensorial coefficient of resistance, validated numerically by a pedagogic model system consisting of an Escherichia coli bacterium and a passive sphere. In a critical test case that studies the scattering angle of the bacterium–sphere pair dynamics, we prove that the near-field hydrodynamics can make a qualitative difference even for this simple two-body system: Calculations based on the proposed model reveal a region in parameter space where the bacterium is trapped by the passive sphere, a phenomenon that is regularly observed in experiments but cannot be explained by any existing model. In the end, we demonstrate that our model also leads to efficient simulation of active fluids with tens of thousands of bacteria, sufficiently large for investigations of many emergent behaviors.
5
Sáenz, Pedro J., Tudor Cristea-Platon e John W. M. Bush. "A hydrodynamic analog of Friedel oscillations". Science Advances 6, n. 20 (maggio 2020): eaay9234. http://dx.doi.org/10.1126/sciadv.aay9234.
Testo completoAbstract (sommario):
We present a macroscopic analog of an open quantum system, achieved with a classical pilot-wave system. Friedel oscillations are the angstrom-scale statistical signature of an impurity on a metal surface, concentric circular modulations in the probability density function of the surrounding electron sea. We consider a millimetric drop, propelled by its own wave field along the surface of a vibrating liquid bath, interacting with a submerged circular well. An ensemble of drop trajectories displays a statistical signature in the vicinity of the well that is strikingly similar to Friedel oscillations. The droplet trajectories reveal the dynamical roots of the emergent statistics. Our study elucidates a new mechanism for emergent quantum-like statistics in pilot-wave hydrodynamics and so suggests new directions for the nascent field of hydrodynamic quantum analogs.
6
LAUGHLIN, R. B. "EMERGENT RELATIVITY". International Journal of Modern Physics A 18, n. 06 (10 marzo 2003): 831–53. http://dx.doi.org/10.1142/s0217751x03014071.
Testo completoAbstract (sommario):
A possible resolution of the incompatibility of quantum mechanics and general relativity is that the relativity principle is emergent. I show that the central paradox of black holes also occurs at a liquid-vapor critical surface of a bose condensate but is resolved there by the phenomenon of quantum criticality. I propose that real black holes are actually phase boundaries of the vacuum analogous to this, and that the Einstein field equations simply fail at the event horizon the way quantum hydrodynamics fails at a critical surface. This can occur without violating classical general relativity anywhere experimentally accessible to external observers. Since the low-energy effects that occur at critical points are universal, it is possible to make concrete experimental predictions about such surfaces without knowing much, if anything about the true underlying equations. Many of these predictions are different from accepted views about black holes — in particular the absence of Hawking radiation and the possible transparency of cosmological black hole surfaces.
7
Zu, C., F. Machado, B. Ye, S. Choi, B. Kobrin, T. Mittiga, S. Hsieh et al. "Emergent hydrodynamics in a strongly interacting dipolar spin ensemble". Nature 597, n. 7874 (1 settembre 2021): 45–50. http://dx.doi.org/10.1038/s41586-021-03763-1.
Testo completo
8
Maji, Soumen, Prashanth Hanmaiahgari, Ram Balachandar, Jaan Pu, Ana Ricardo e Rui Ferreira. "A Review on Hydrodynamics of Free Surface Flows in Emergent Vegetated Channels". Water 12, n. 4 (24 aprile 2020): 1218. http://dx.doi.org/10.3390/w12041218.
Testo completoAbstract (sommario):
This review paper addresses the structure of the mean flow and key turbulence quantities in free-surface flows with emergent vegetation. Emergent vegetation in open channel flow affects turbulence, flow patterns, flow resistance, sediment transport, and morphological changes. The last 15 years have witnessed significant advances in field, laboratory, and numerical investigations of turbulent flows within reaches of different types of emergent vegetation, such as rigid stems, flexible stems, with foliage or without foliage, and combinations of these. The influence of stem diameter, volume fraction, frontal area of stems, staggered and non-staggered arrangements of stems, and arrangement of stems in patches on mean flow and turbulence has been quantified in different research contexts using different instrumentation and numerical strategies. In this paper, a summary of key findings on emergent vegetation flows is offered, with particular emphasis on: (1) vertical structure of flow field, (2) velocity distribution, 2nd order moments, and distribution of turbulent kinetic energy (TKE) in horizontal plane, (3) horizontal structures which includes wake and shear flows and, (4) drag effect of emergent vegetation on the flow. It can be concluded that the drag coefficient of an emergent vegetation patch is proportional to the solid volume fraction and average drag of an individual vegetation stem is a linear function of the stem Reynolds number. The distribution of TKE in a horizontal plane demonstrates that the production of TKE is mostly associated with vortex shedding from individual stems. Production and dissipation of TKE are not in equilibrium, resulting in strong fluxes of TKE directed outward the near wake of each stem. In addition to Kelvin–Helmholtz and von Kármán vortices, the ejections and sweeps have profound influence on sediment dynamics in the emergent vegetated flows.
9
Cornacchia, Loreta, Geraldene Wharton, Grieg Davies, Robert C. Grabowski, Stijn Temmerman, Daphne van der Wal, Tjeerd J. Bouma e Johan van de Koppel. "Self-organization of river vegetation leads to emergent buffering of river flows and water levels". Proceedings of the Royal Society B: Biological Sciences 287, n. 1931 (15 luglio 2020): 20201147. http://dx.doi.org/10.1098/rspb.2020.1147.
Testo completoAbstract (sommario):
Global climate change is expected to impact hydrodynamic conditions in stream ecosystems. There is limited understanding of how stream ecosystems interact and possibly adapt to novel hydrodynamic conditions. Combining mathematical modelling with field data, we demonstrate that bio-physical feedback between plant growth and flow redistribution triggers spatial self-organization of in-channel vegetation that buffers for changed hydrological conditions. The interplay of vegetation growth and hydrodynamics results in a spatial separation of the stream into densely vegetated, low-flow zones divided by unvegetated channels of higher flow velocities. This self-organization process decouples both local flow velocities and water levels from the forcing effect of changing stream discharge. Field data from two lowland, baseflow-dominated streams support model predictions and highlight two important stream-level emergent properties: vegetation controls flow conveyance in fast-flowing channels throughout the annual growth cycle, and this buffering of discharge variations maintains water depths and wetted habitat for the stream community. Our results provide important evidence of how plant-driven self-organization allows stream ecosystems to adapt to changing hydrological conditions, maintaining suitable hydrodynamic conditions to support high biodiversity.
10
Suh, In-Saeng, Grant J. Mathews, J. Reese Haywood e N. Q. Lan. "Analysis of the Conformally Flat Approximation for Binary Neutron Star Initial Conditions". Advances in Astronomy 2017 (2017): 1–12. http://dx.doi.org/10.1155/2017/6127031.
Testo completoAbstract (sommario):
The spatially conformally flat approximation (CFA) is a viable method to deduce initial conditions for the subsequent evolution of binary neutron stars employing the full Einstein equations. Here we analyze the viability of the CFA for the general relativistic hydrodynamic initial conditions of binary neutron stars. We illustrate the stability of the conformally flat condition on the hydrodynamics by numerically evolving ~100 quasicircular orbits. We illustrate the use of this approximation for orbiting neutron stars in the quasicircular orbit approximation to demonstrate the equation of state dependence of these initial conditions and how they might affect the emergent gravitational wave frequency as the stars approach the innermost stable circular orbit.
Tesi sul tema "Emergent hydrodynamics"
1
Liu, David. "Flow through Rigid Vegetation Hydrodynamics". Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/35068.
Testo completoAbstract (sommario):
Better understanding of the role of vegetation in the transport of fluid and pollutants requires improved knowledge of the detailed flow structure within the vegetation. Instead of spatial averaging, this study uses discrete measurements at multiple locations within the canopy to develop velocity and turbulence intensity profiles and observe the changes in the flow characteristics as water travels through a vegetation array simulated by rigid dowels. Velocity data were collected with a one dimensional laser Doppler velocimeter (LDV) under single layer emergent and submerged flow conditions, and through two layers of vegetation. The effects of dowel arrangement, density, and roughness are also examined under the single layer experiments. The results show that the velocity within the vegetation array is constant with depth and the velocity profile is logarithmic above it. The region immediately behind a dowel, where the vorticity and turbulence intensity are highest, is characterized by a velocity spike near the bed and an inflection point near the top of the dowel arrays. With two dowel layers, the velocity profile in the region behind a tall dowel exhibits multiple inflection points and the highest turbulence intensities are found there.Master of Science
2
Maji, S., P. R. Hanmaiahgari, R. Balachandar, Jaan H. Pu, A. M. Ricardo e R. M. L. Ferreira. "A review on hydrodynamics of free surface flows in emergent vegetated channels". MDPI, 2020. http://hdl.handle.net/10454/17820.
Testo completoAbstract (sommario):
YesThis review paper addresses the structure of the mean flow and key turbulence quantities in free-surface flows with emergent vegetation. Emergent vegetation in open channel flow affects turbulence, flow patterns, flow resistance, sediment transport, and morphological changes. The last 15 years have witnessed significant advances in field, laboratory, and numerical investigations of turbulent flows within reaches of different types of emergent vegetation, such as rigid stems, flexible stems, with foliage or without foliage, and combinations of these. The influence of stem diameter, volume fraction, frontal area of stems, staggered and non-staggered arrangements of stems, and arrangement of stems in patches on mean flow and turbulence has been quantified in different research contexts using different instrumentation and numerical strategies. In this paper, a summary of key findings on emergent vegetation flows is offered, with particular emphasis on: (1) vertical structure of flow field, (2) velocity distribution, 2nd order moments, and distribution of turbulent kinetic energy (TKE) in horizontal plane, (3) horizontal structures which includes wake and shear flows and, (4) drag effect of emergent vegetation on the flow. It can be concluded that the drag coefficient of an emergent vegetation patch is proportional to the solid volume fraction and average drag of an individual vegetation stem is a linear function of the stem Reynolds number. The distribution of TKE in a horizontal plane demonstrates that the production of TKE is mostly associated with vortex shedding from individual stems. Production and dissipation of TKE are not in equilibrium, resulting in strong fluxes of TKE directed outward the near wake of each stem. In addition to Kelvin–Helmholtz and von Kármán vortices, the ejections and sweeps have profound influence on sediment dynamics in the emergent vegetated flows.
3
El, Allaoui Nazha. "Modified hydrodynamics in fragmented canopies exposed to oscillatory flows". Doctoral thesis, Universitat de Girona, 2016. http://hdl.handle.net/10803/403066.
Testo completoAbstract (sommario):
The general objective of this doctoral thesis has been to contribute to understand the modification of hydrodynamics in fragmented canopies. The effect of different parameters such as the canopy density, the plant height and flexibility and the architecture of the gap has been studied. Ecological implications of the results have been discussed. Results point that the fluxes of biological particles, nutrients and sediments in fragmented canopies are modified compared with those for non-fragmented canopies, impacting on their ecological function. Therefore, canopies may optimize their structural characteristics to moderate the impact of fragmentation. This thesis shows that plant density and flexibility interacts with the gap width and the degree of fragmentation to facilitate sheltering in a manner not previously predictedL'objectiu general d'aquesta tesi doctoral ha estat contribuir a entendre la modificació de la hidrodinàmica en praderies aquàtiques fragmentades. En aquesta tesi doctoral s’ha estudiat l'efecte de diferents paràmetres com ara la densitat de la praderia, l'alçada de la planta i la flexibilitat i l'arquitectura dels blancs sense vegetació. S'han discutit les conseqüències ecològiques dels resultats. Els resultats assenyalen que els fluxos de partícules biològiques, nutrients i sediments en praderies fragmentades són modificats en comparació amb els que s’obtindrien en praderies no fragmentades, fet que modifica la seva funció ecològica. Per tant, les praderies poden optimitzar les seves característiques estructurals per moderar l'impacte de la fragmentació. Aquesta tesi mostra que la densitat de plantes i flexibilitat interactua amb les dimensions del blanc i el grau de fragmentació per facilitar el refugi d'una manera no prevista anteriorment
4
Alarcón, Oseguera Francisco. "Computational study of the emergent behavior of micro-swimmer suspensions". Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/394065.
Testo completoAbstract (sommario):
It is known that active particles induce emerging patterns as a result of their dynamic interactions, giving rise to amazing collective motions, such as swarming or clustering. Here we present a systematic numerical study of self-propelling particles; our main goal is to characterize the collective behavior of suspensions of active particles as a result of the competition among their propulsion
activity and the intensity of an attractive pair potential. Active particles are modeled using the squirmer model. Due to its hydrodynamic nature, we are able to classify the squirmer swimmer activity in terms of the stress it generates (referred to as pullers or pushers). We show that these active stresses play a central role in the emergence of collective motion. We have found that hydrodynamics drive the coherent swimming between swimmers while the swimmer direct interactions, modeled by a Lennard-Jones potential, contributes to the swimmers' cohesion. This competition gives rise to two different regimes where giant density fluctuations (GDF) emerge. These two regimes are differentiated by the suspension alignment; one regime has GDF in aligned suspensions whereas the other regime has GDF of suspensions with an isotropic orientated state. All the simulated squirmer suspensions shown in this study were characterized by a thorough analysis of global properties of the squirmer suspensions as well as a complementary cluster analysis.
Active matter refers generically to systems composed of self-driven units, active particles, each capable of converting stored or ambient free energy into systematic movement. Examples of active systems are found at all length scales and could be classified in living and nonliving systems such as microorganisms, tissues and organisms, animal groups, self- propelled colloids and artificial nanoswimmers. Specifically, at the micro and nano scale we find an enormous range of interesting systems both biological and artificial; e.g. spermatozoa that fuse with the ovum during fertilization, the bacteria that inhabit our guts, the protozoa in our ponds, the algae in the ocean; these are but a few examples of a wide biological spectrum. In the artificial world we have self- healing colloidal crystals and membranes as well as self- assembled microswimmers and robots. Experiments in this field are now developing at a very rapid pace and new theoretical ideas are needed to bring unity to the field and identify "universal" behavior in these internally driven systems.
One important feature of active matter is that their elements can develop emergent, coordinated behavior; collective motion constitutes one of the most common and spectacular example. Collective motion is ubiquitous and at every scale, from herds of large mammals to amoeba and bacteria colonies, down to the cooperative behavior of molecular motors in the cell. The behavior of large fish schools and the dance of starling flocks at dusk are among the most spectacular examples. From a physical perspective collective motion emerges from a spontaneous symmetry breaking that allows for long-range orientational orden The different mechanisms responsible for such symmetry breaking are still not completely understood. We have performed a systematic numerical study of interactive micro-swimmer suspensions building on the squirmer model, introduced by Lighthill. Since the squirmer identifies systematically the hydrodynamic origin of self-propulsion and stress generation it provides a natural scheme to scrutinize the impact that the different features associated to self-propulsion in a liquid medium have in the collective dynamics of squirmer suspensions. In this abstract we describe the simulation scheme and how squirmers are modeled, then some of the main results are discussed and finally we conclude emphasizing the main implications of the results obtained.Los sistemas activos se definen como materiales fuera del equilibrio termodinámico compuestos por muchas unidades interactuantes que individualmente consumen energía y colectivamente generan movimiento o estreses mecánicos. Ejemplos se pueden encontrar en un enorme rango de escalas de longitud, desde el mundo biológico hasta artificial, incluyendo organismos unicelulares, tejidos y organismos pluricelulares, grupos de animales, coloides auto-propulsados y nano-nadadores artificiales. Actualmente se están desarrollando experimentos en este campo a un ritmo muy veloz, en consecuencia son necesarias nuevas ideas teóricas para traer unidad al campo de estudio e identificar comportamientos “universales” en estos sistemas propulsados internamente. El objetivo de esta tesis es el estudiar mediante simulaciones numéricas, el comportamiento colectivo de un modelo de micro-nadadores. En particular, el modelo de squirmers, donde el movimiento del fluido es axi-simétrico. Existen estructuras coherentes que emergen de estos sistemas así que, el entender si las estructuras coherentes son generadas por la firma hidrodinámica intrínseca de los squirmers individuales o por un efecto de tamaño finito se vuelve algo de primordial importancia. Nosotros también estudiamos la influencia que tiene la geometría en la aparición de estructuras coherentes, la interacción directa entre las partículas, la concentración, etc.
5
Cecile, Mario Guillaume. "Exploring quantum dynamics : from hydrodynamics to measurement induced phase transition". Electronic Thesis or Diss., CY Cergy Paris Université, 2024. http://www.theses.fr/2024CYUN1298.
Testo completoAbstract (sommario):
Dans cette thèse, nous plongeons dans le monde de la dynamique quantique, dans le but de comprendre les comportements complexes qui se manifestent dans les systèmes quantiques à plusieurs corps et l'émergence des comportements hydrodynamiques. À travers les chapitres, nous simplifions les concepts clés essentiels à la compréhension du fonctionnement des systèmes quantiques. Le Chapitre 1 présente un aperçu des concepts fondamentaux sur les phénomènes émergents dans les systèmes quantiques intégrables et l'hydrodynamique généralisée, qui est essentiel pour comprendre les complexités de la dynamique quantique. De plus, nous proposons une introduction approfondie aux États de Produit de Matrice, qui sont un outil précieux pour simuler efficacement la dynamique quantique dans les systèmes 1D. Dans le Chapitre 2, nous développons un modèle pour décrire la relaxation des hélices de spin en utilisant le cadre de la dynamique hydrodynamique généralisée avec des corrections diffusives et une version modifiée de l'approximation de la densité locale. Notre analyse démontre que ce cadre hydrodynamique reproduit avec précision les dynamiques de relaxation observées expérimentalement. De plus, il prédit le comportement de relaxation à long terme, qui dépasse les échelles de temps accessibles expérimentalement. Notre cadre théorique élucide l'apparition de régimes temporels présentant une diffusion apparemment anormale et met en évidence l'asymétrie entre les régimes d'anisotropie positifs et négatifs à court et à moyen terme. Le Chapitre 3 explore les phénomènes intrigants observés dans le régime de l'axe facile |Δ| ≥ 1, où les états initiaux sans fluctuations magnétiques se relaxent localement vers un état d'équilibre exotique que nous appellerons ensemble généralisé de Gibbs compressé. Au point isotrope, nous avons trouvé un comportement inhabituel qui dépend explicitement de l'état initial. En particulier, pour l'état de Néel, nous avons trouvé des fluctuations étendues et un exposant dynamique super-diffusif compatible avec l'universalité de Kardar-Parisi-Zhang. Pour un autre état initial sans fluctuations, par exemple, l'état produit de singulets de spin, nous avons trouvé une mise à l'échelle diffusive. Dans le Chapitre 4, nous étudions l'évolution temporelle de chaînes de spin quantiques étendues sous surveillance continue en utilisant des états de produit de matrice avec une dimension de liaison fixe, en employant l'algorithme du Principe Variationnel Dépendant du Temps. Cet algorithme produit une évolution non linéaire classique efficace avec une charge conservée, offrant une approximation de l'évolution quantique réelle avec une certaine erreur. Nous constatons que le taux d'erreur présente une transition de phase lorsque la force de la surveillance varie, et cette transition peut être identifiée avec précision grâce à une analyse de mise à l'échelle avec des dimensions de liaison relativement petites. Notre approche permet une détermination numérique efficace des paramètres critiques associés aux transitions de phase induites par la mesure dans les systèmes quantiques à plusieurs corps. De plus, en présence d'une charge de spin globale U(1), nous observons une transition distincte d'affinement de la charge, qui se produit indépendamment de la transition d'entrelacement. Cette transition est identifiée en analysant les fluctuations de charge dans un sous-ensemble local du système sur des périodes de temps étendues. Nos découvertes mettent en évidence l'efficacité de l'évolution temporelle TDVP comme moyen de détecter les transitions de phase induites par la mesure dans des systèmes de dimensions et de tailles variables.Enfin, le dernier chapitre offre un résumé conclusif des résultats et discute des pistes potentielles pour la recherche futureIn this thesis, we take a deep dive into the world of quantum dynamics, aiming to understand the complex behaviours that arise in quantum many-body systems and the emergence of hydrodynamics behaviour. Throughout the chapters, we simplify key concepts essential for understanding how quantum systems operate. Chapter 1 presents an overview of fundamental concepts on emergent phenomena in quantum integrable systems and generalized hydrodynamics, which is essential to understand the complexities of quantum dynamics. Additionally, we offer an in-depth introduction to Matrix Product States, which are a valuable tool for efficiently simulating quantum dynamics in 1D systems. In Chapter 2, we develop a model to describe the relaxation of spin helices using the framework of generalized hydrodynamics with diffusive corrections and a modified version of the local density approximation. Our analysis demonstrates that this hydrodynamic framework accurately reproduces the experimentally observed relaxation dynamics. Additionally, it predicts the long-term relaxation behaviour, which lies beyond the experimentally accessible time scales. Our theoretical framework elucidates the occurrence of temporal regimes exhibiting seemingly anomalous diffusion and highlights the asymmetry between positive and negative anisotropy regimes at short and intermediate time intervals. Chapter 3 delves into the intriguing phenomena observed in the easy-axis regime |Δ| ≥ 1, where initial states with zero magnetic fluctuations instead locally relax to an exotic equilibrium states that we will refer to as squeezed generalized Gibbs ensemble. At the isotropic point, interestingly, we found an unusual behaviour which explicitly depend on the initial state. Namely, for the Néel state, we found extensive fluctuations and a super-diffusive dynamical exponent compatible with Kardar-Parisi-Zhang universality. For another non-fluctuating initial state, e.g., product state of spin singlets, we instead found diffusive scaling. In Chapter 4, we investigate the time evolution of an extended quantum spin chains under continuous monitoring using matrix product states with a fixed bond dimension, employing the Time-Dependent Variational Principle algorithm. This algorithm yields an effective classical nonlinear evolution with a conserved charge, offering an approximation to the true quantum evolution with some error. We find that the error rate exhibits a phase transition as the strength of the monitoring varies, and this transition can be accurately identified through scaling analysis with relatively small bond dimensions. Our approach enables efficient numerical determination of critical parameters associated with measurement-induced phase transitions in many-body quantum systems. Furthermore, in the presence of U(1) global spin charge, we observe a distinct charge-sharpening transition, which occurs independently of the entanglement transition. This transition is identified by analysing the charge fluctuations within a local subset of the system over extended time periods. Our findings highlight the effectiveness of TDVP time evolution as a means to detect measurement-induced phase transitions in systems of varying dimensions and sizes.Finally, the last chapter provides a conclusive summary of the findings and discusses potential avenues for future research
6
Feriani, Luigi. "Understanding the collective dynamics of motile cilia in human airways". Thesis, University of Cambridge, 2019. https://www.repository.cam.ac.uk/handle/1810/288418.
Testo completoAbstract (sommario):
Eukaryotic organisms rely on the coordinated beating of motile cilia for a multitude of fundamental reasons. In smaller organisms, such as Paramecium and the single cell alga Chlamydomonas reinhardtii, it is a matter of propulsion, to swim towards a higher concentration of nutrients or away from damaging environments. Larger organisms use instead the coordinated motion of cilia to push fluid along an epithelium: examples common to mammals are the circulation of cerebrospinal fluid in the brain, the transport of ovules in the fallopian tubes, and breaking the left/right symmetry in the embryo. Another notable example, and one that is central to this thesis, is mucociliary clearance in human airways: A carpet of motile cilia helps keeping the cell surface free from pathogens and foreign particles by constantly evacuating from lungs, bronchi, and trachea a barrier of mucus. The question of how motile cilia interact with one another to beat in a coordinated fashion is an open and pressing one, with immediate implications for the medical community. In order for the fluid propulsion to be effective, the motion of cilia needs to be phase-locked across significant distances, in the form of travelling waves (``metachronal waves''). It is still not known how this long-range coordination emerges from local rules, as there is no central node regulating the coordination among cilia. In the first part of this thesis I will focus on studying the coordination in carpets of cilia with a top-down approach, by proposing, implementing, and applying a new method of analysing microscope videos of ciliated epithelia. Chapter 1 provides the reader with an introduction on motile cilia and flagella, treating their structure and motion and reporting the different open questions currently tackled by the scientific community, with particular interest in the coordination mechanisms of cilia and the mucociliary clearance apparatus. Chapter 2 introduces Differential Dynamic Microscopy (DDM), a powerful and versatile image analysis tool that bridges the gap between spectroscopy and microscopy by allowing to perform scattering experiments on a microscope. The most interesting aspects of DDM for this work are that it can be applied to microscope videos where it is not possible to resolve individual objects in the field of view, and it requires no user input. These two characteristics make DDM a perfect candidate for analysing several hundred microscope videos of weakly scattering filaments such as cilia. In Chapter 3 I will present how it is possible to employ DDM to extract a wealth of often-overlooked information from videos of ciliated epithelia: DDM can successfully probe the ciliary beat frequency (CBF) in a sample, measure the direction of beating of the cilia, and detect metachronal waves and read their direction and wavelength. In vitro ciliated epithelia however often do not show perfect coordination or alignment among cilia. For the analysis of these samples, where the metachronal coordination might not be evident, we developed a new approach, called multiscale DDM (multiDDM), to measure a coordination length scale, a characteristic length of the system over which the coordination between cilia is lost. The new technique of multiDDM is employed in Chapter 4 to study how the coordination among cilia changes as a response to changes in the rheology of the mucous layer. In particular, we show that cilia beating under a thick, gel-like mucus layer show a larger coordination length scale, as if the mucus acted as an elastic raft effectively coupling cilia over long distances. This is corroborated by the coordination length scale being larger in samples from patients affected by Cystic Fibrosis than in healthy samples, and much shorter when the mucus layer is washed and cilia therefore beat in a near-Newtonian fluid. We then show how it is possible to employ multiDDM to measure the effectiveness of drugs in recovering, in CF samples, a coordination length scale typical of a healthy phenotype. In the second part I will focus instead on the single cilium scale, showing how we can attempt to link the beating pattern of cilia to numerical simulations studying synchronisation in a model system. In particular in Chapter 5 I will describe our approach to quantitatively describe the beating pattern of single cilia obtained from human airway cells of either healthy individuals or patients affected by Primary Ciliary Dyskinesia. Our description of the beating pattern, and the selection of a few meaningful, summary parameters, are then shown to be accurate enough to discriminate between different mutations within Primary Ciliary Dyskinesia. In Chapter 6 instead I report the results obtained by coarse-graining the ciliary beat pattern into a model system consisting of two ``rotors''. The rotors are simulated colloidal particles driven along closed trajectories while leaving their phase free. In my study, the trajectories followed by the rotors are analytical fits of experimental trajectories of the centre of drag of real cilia. The rotors, that are coupled only via hydrodynamics interactions, are seen to phase-lock, and the shape of the trajectory they are driven along is seen to influence the steady state of the system.
7
Jerbi, Zouhaier. "Contribution à l'étude de l'étalement de matériaux fondus avec solidification". Grenoble INPG, 1996. http://www.theses.fr/1996INPG0216.
Testo completoAbstract (sommario):
Ce travail s'inscrit dans le cadre general de l'etude des accidents graves qui peuvent survenir sur un reacteur nucleaire a eau sous pression. Dans ce vaste programme, on envisage le percement de la cuve du reacteur par le cur en fusion (corium). Il se pose alors le probleme du refroidissement a long terme de ce fluide, largement conditionne par la repartition spatiale de ce fluide sur les structures se trouvant sous la cuve. Le but ultime de cette these est la modelisation des phenomenes physiques lies a l'etalement et la validation d'un logiciel de calcul. Le programme corine, lance au commissariat a l'energie atomique, est concue pour fournir les donnees experimentales necessaires. L'etude des aspects hydrodynamiques a montre l'existence de trois differents regimes qui se distinguent par la nature des forces motrices et retardatrices qui controlent l'ecoulement: gravite-inertie, gravite-viscosite et tension superficielle-viscosite. Les essais realises sur les dispositifs corine ont permis de valider les modeles analytiques proposes. Apres les aspects hydrodynamiques, nous avons passe a l'etalement avec solidification, et a l'analyse du logiciel meltspread, qui constitue le seul outil numerique capable de calculer l'etalement des materiaux fondus sur du beton. Pour la validation proprement dit, nous avons commence par les aspects hydrodynamiques et les resultats obtenus sont en bon accord avec les modeles rencontres dans la litterature ainsi qu'avec les essais en regime inertiel et visqueux. Des calculs d'etalement avec solidification ete aussi effectue et montre une description assez coherente des phenomenes de l'etalement et de la solidification. Une analyse qualitative des resultats de meltspread, obtenue par la comparaison avec les experiences corine avec gel, donne un accord tres satisfaisant
8
Cheung, Chun Ming Mark. "Magnetic flux emergence in the solar photosphere". Doctoral thesis, 2006. http://hdl.handle.net/11858/00-1735-0000-0006-B597-A.
Testo completoLibri sul tema "Emergent hydrodynamics"
1
M, Soward A., a cura di. Fluid dynamics and dynamos in astrophysics and geophysics: Reviews emerging from the Durham Symposium on Astrophysical Fluid Mechanics, July 29 to August 8, 2002. Boca Raton: CRC Press, 2005.
Cerca il testo completo
2
Emerging Techniques in Drag Reduction. Wiley, 1996.
Cerca il testo completo
3
Meshell, Lida. Hydrodynamic Cavitation : an Emerging Technology in a Chemical Process Industry: Characteristics of Fluid Flow. Independently Published, 2021.
Cerca il testo completoCapitoli di libri sul tema "Emergent hydrodynamics"
1
Maji, Soumen, Susovan Pal, Prashanth Reddy Hanmaiahgari e Vikas Garg. "Turbulent Hydrodynamics Along Lateral Direction in and Around Emergent and Sparse Vegetated Open-Channel Flow". In Water Science and Technology Library, 455–67. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-55125-8_39.
Testo completo
2
Pal, Debasish, Bapon Halder e Prashanth R. Hanmaiahgari. "Comparison of Turbulent Hydrodynamics with and without Emergent and Sparse Vegetation Patch in Free Surface Flow". In Water Science and Technology Library, 205–19. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-55125-8_18.
Testo completo
3
Mahanti, Naveen Kumar, Subir Kumar Chakraborty, S. Shiva Shankar e Ajay Yadav. "Hydrodynamic Cavitation Technology for Food Processing and Preservation". In Emerging Thermal and Nonthermal Technologies in Food Processing, 199–224. Includes bibliographical references and index.: Apple Academic Press, 2020. http://dx.doi.org/10.1201/9780429297335-8.
Testo completo
4
Claus, James R. "Application of hydrodynamic shock wave processing associated with meat and processed meat products". In Emerging Technologies in Meat Processing, 171–210. Chichester, UK: John Wiley & Sons, Ltd, 2016. http://dx.doi.org/10.1002/9781118350676.ch7.
Testo completo
5
Rios, S., A. Vianada Fonseca, L. Ribeiro, C. Cengiz e S. J. M. van Eekelen. "Centrifuge model tests to evaluate the stability of embankments in hydrodynamic conditions". In Geotechnical Engineering Challenges to Meet Current and Emerging Needs of Society, 1920–22. London: CRC Press, 2024. http://dx.doi.org/10.1201/9781003431749-360.
Testo completo
6
Singh, Daljeet, Erkki Vihriälä, Mariella Särestöniemi e Teemu Myllylä. "Microwave Technique Based Noninvasive Monitoring of Intracranial Pressure Using Realistic Phantom Models". In Communications in Computer and Information Science, 413–25. Cham: Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-59091-7_27.
Testo completoAbstract (sommario):
AbstractMicrowave technology is emerging as a promising candidate in the field of medical diagnosis and imaging and has paved the way for a transition from invasive to non-invasive methods of monitoring various biological phenomena inside the human body. Intracranial Pressure (ICP) is considered to be a very important parameter by medical practitioners for assessing the health of a subject. Accurate, prolonged, and noninvasive measurement of ICP is still an open area of research with no clinical success so far. Therefore, in this paper, a microwave-based method for non-invasive monitoring of ICP is proposed. The setup utilizes flexible, thin, small, and lightweight planner antennas that are very suitable for non-invasive monitoring of ICP from the skin without compromising the comfort of subject. The proposed microwave method is tested on a realistic head phantom model which imitates the functioning of hydrodynamics in a real human head. The measurement results from the proposed method are verified using invasive pressure sensors. It is deduced from numerous trials that the proposed microwave system can detect small changes in ICP pressure and its response is analogous to actual pressure values measured by invasive pressure sensors.
7
Bellona, Christopher L., e Jörg E. Drewes. "Comparing the Phenomenological and Hydrodynamic Modeling Approaches for Describing the Rejection of Emerging Nonionic Organic Contaminants by a Nanofiltration Membrane". In ACS Symposium Series, 397–420. Washington, DC: American Chemical Society, 2010. http://dx.doi.org/10.1021/bk-2010-1048.ch020.
Testo completo
8
Camarillo E., R. M., J. A. Padilla M., J. A. García M., C. A. Ocón D., Ch Reyes C., J. M. Camarillo E. e R. Rodríguez R. "Auto-Calibration and Micro-Flow Injection Procedure Based on Automated Hydrodynamic System for Spectrophotometric Determination of Cobalt". In Emerging Challenges for Experimental Mechanics in Energy and Environmental Applications, Proceedings of the 5th International Symposium on Experimental Mechanics and 9th Symposium on Optics in Industry (ISEM-SOI), 2015, 255–63. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-28513-9_36.
Testo completo
9
Ranjan, P., P. Fischer e R. O. Tinoco. "Investigation of hydrodynamics and sediment transport within emergent vegetation canopy". In River Flow 2020, 1595–600. CRC Press, 2020. http://dx.doi.org/10.1201/b22619-222.
Testo completo
10
Limmer, David T. "Fundamental postulates and definitions". In Statistical Mechanics and Stochastic Thermodynamics, 1–30. Oxford University PressOxford, 2024. http://dx.doi.org/10.1093/oso/9780198919858.003.0001.
Testo completoAbstract (sommario):
Abstract In this chapter, we first build the theory of equilibrium statistical mechanics formally, through postulates, definitions and mathematical inference, in an effort to understand properties of sys-tems at rest, and their emergent thermodynamics. Later, we will generalize the theory to confront systems’ motion, employing principles of stochastic thermodynamics, and making connections to hydrodynamics. Of primary concern in this theory is the use of the mathematics of probability, as the tremendous numbers of atoms in any macro- scopic object lend themselves naturally to a statistical description. As a consequence, the primary objective is to first deduce the likelihood of a specific arrangement of atoms. The organization of likelihoods of molecular arrangements is encoded in a probability distribution. The establishment of this probability distribution is our first goal.
Atti di convegni sul tema "Emergent hydrodynamics"
1
Gupta, Aditya, Manasa R. Behera e Amin Heidarpour. "Numerical Modeling of Wave Damping Induced by Emerged Moving Vegetation". In ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/omae2020-18588.
Testo completoAbstract (sommario):
Abstract The unprecedented risk of global warming has put the coastal population at greater risk from coastal hazards due to an increase in sea level and other storm-related activities. Coastal vegetations are one of the soft solutions that can be implemented for wave mitigation. This study aims to investigate the wave damping effect of a regular wave by emergent moving coastal vegetation. Smoothed Particle Hydrodynamics (SPH), a particle-based method is used for generating fluid particles and Differential Variational Inequality (DVI) is coupled with SPH to deal with the dynamics of moving vegetation. The 3-D numerical model is simulated using an open-source tool DualSPHysics 4.4. The model is tested for regular wave height (H) of 0.08 m, wave period (T) of 2 seconds in a water depth (d) of 0.40 and 0.45 m for two relative vegetation height (h/d) of 1.25 and 1.11 respectively. The results are validated with the experimental study for the rigid vegetation and then the model is extended for moving vegetation. The results indicate that the wave damping is overestimated in the case of rigid vegetation. Further, the application of this study can be extended for studying the tsunami hazard mitigation in the presence of coastal forest.
2
Chen, Yuxiang, e Ye Gao. "Hydrodynamics Simulation on Axisymmetric Bodies Emerging from an Infinite Moving Plane". In 2010 International Conference on Computational Intelligence and Software Engineering (CiSE). IEEE, 2010. http://dx.doi.org/10.1109/cise.2010.5676715.
Testo completo
3
Sun, Zhiyong, Hui Li e Heyun Miao. "Numerical Investigation on the Hydrodynamic Characteristics in the Tank of Aquaculture Vessel". In ASME 2024 43rd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2024. http://dx.doi.org/10.1115/omae2024-126082.
Testo completoAbstract (sommario):
Abstract At present, deep-sea aquaculture faces numerous challenges, encompassing issues such as water body eutrophication, fish lice diseases, and adverse sea conditions that cause damage to aquaculture equipment. In response to these challenges, a mobile aquaculture vessel equipped with recirculating aquaculture systems has emerged as a preferred solution. These systems demonstrate precise water control capabilities, ensuring optimal aquaculture water quality and mitigating the occurrence of fish diseases. In contrast to deep-sea aquaculture cages, the hull structure of aquaculture vessels exhibits superior resilience to extreme sea conditions, thereby ensuring the safety of aquaculture operations. The hydrodynamic characteristics of aquaculture tanks play a pivotal role in the growth and health of fish. The aquaculture vessel, representing an emerging innovation, currently lacks a robust foundation of hydrodynamic knowledge to effectively support aquaculture production. In this paper hydrodynamic characteristics of aquaculture tanks are investigated based on the computational fluid dynamics (CFD) method, focusing on param such as flow velocity, vortices, and flow field uniformity. The analysis reveals the existence of low flow velocity zones and dead zones in the near-corner wall region of the octagonal aquaculture tank. In the region above water depth = −3 m, a noticeable velocity gradient and lower uniformity are observed. Notably, an increase in inlet flow velocity results in an improvement in the flow field uniformity in this region.
4
Paczkowski, K. W., P. Zhang, R. Rogers e N. Richardson. "Fluid Structure Interaction Study on Dynamic Response of a Capped Drilling Riser Filled With Mud". In ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/omae2014-23329.
Testo completoAbstract (sommario):
In the offshore drilling, during emergency disconnect scenario the drilling operation must not be maintained and forced LMRP disconnect procedure takes place [1,2]. Such procedure allows drilling mud to interact with seawater. The paper presents hydrodynamic behavior of a drilling riser when mud is retained and not interacted with seawater. A two-way coupled fluid-structure interaction (FSI) model between a simplified drilling riser structure and mud fluid was studied through techniques of computational fluid dynamics (CFD). The volume of fluid (VOF) hydrodynamics model was used with commercially available software STAR-CCM+ [3]. A 3D finite element (FE) model of a drilling riser was created in FE software ABAQUS [4] to determine the stress and deflection of structural parts of the model due to hydrodynamic loads. In the model, the compressibility [5] and non-linear behavior of the mud was included. The dynamic frequencies of the two domains and possible resonance of the coupled system were investigated. The aim of the study was to verify the dynamic behavior of a riser system with a drilling mud enclosed within the system. The authors of this paper know no similar study of such a problem.
5
Tomiyama, Ryo, Tatsuhiko Uchida, Daisuke Kobayashi, Misako Hatono e Satoshi Yokojima. "Effects of an emergent cylinder in a group on water flows and evaluation of hydrodynamic force". In Proceedings of the 39th IAHR World Congress From Snow to Sea. Spain: International Association for Hydro-Environment Engineering and Research (IAHR), 2022. http://dx.doi.org/10.3850/iahr-39wc252171192022958.
Testo completo
6
Vasan, A. Mercy, e V. Gopalakrishnan. "Hydrodynamic Modeling of Circulating Fluidised Bed Boilers: An Overview". In ASME 2012 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/imece2012-87191.
Testo completoAbstract (sommario):
The Circulating Fluidized Bed (CFB) boilers have emerged as flexible, environment-friendly equipment in recent years. Though less than 20 years old, the technology has already proved its maturity and has started replacing the Pulverized Fuel (PF) combustion in specific areas. Retrofitting and scaling-up of CFB boilers require, among other things, a clear understanding of the complex flow patterns observed in various zones of the boiler and formulating them into suitable computational models. This paper attempts to get an overview of the different modeling approaches found in literature in this regard, so that an appropriate model could be arrived at for designing large commercial-scale boilers.
7
Dmitriev, Alexandr S. "Fluctuation Hydrodynamics, Thermophoresis of Nanoparticles and Heat Transfer in Nanofluids". In ASME 2012 Third International Conference on Micro/Nanoscale Heat and Mass Transfer. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/mnhmt2012-75205.
Testo completoAbstract (sommario):
In this paper we studied in the framework of two-fluid hydrodynamics with fluctuations the behavior of nanoparticles in the liquid with temperature gradient [1, 2]. It is shown that the acoustic long-wave fluctuations are not damped in liquids (long-wavelength phonons) and leads to an additional force acting on the nanoparticles, as well as lead to the emergence of a new force of thermophoresis [3], which is proportional to the temperature in three second degree. It is also shown that such a thermophoresis force arising under the two-fluid hydrodynamics, can lead to instability of an ensemble of nanoparticles in the presence of a temperature gradient. The last effect leads to the possible merger of the nanoparticles in the form of elongated clusters. The appearance of such clusters on the one hand, leads to an increase in effective thermal conductivity of nanofluids, and secondly, appearing elongated clusters contribute to the propagation of long-wavelength phonons along of such clusters. In fact, this new type of heat transfer in nanofluids, which must be considered in addition to the Brownian motion of nanoparticles.
8
Laraqi, N., M. M. Rashidi, J. M. Garcia de Maria e A. Bairi. "Thermo-hydrodynamic behaviour of a thin lubricant film". In 2010 3rd International Conference on Thermal Issues in Emerging Technologies Theory and Applications (ThETA). IEEE, 2010. http://dx.doi.org/10.1109/theta.2010.5766392.
Testo completo
9
Degtyarev, A., I. Gankevich e V. Khramushin. "DIRECT COMPUTATIONAL EXPERIMENT IN STORM HYDRODYNAMICS OF MARINE OBJECTS". In 9th International Conference "Distributed Computing and Grid Technologies in Science and Education". Crossref, 2021. http://dx.doi.org/10.54546/mlit.2021.62.36.001.
Testo completoAbstract (sommario):
The paper presents and discusses a new computer toolkit for assessing the seaworthiness of a ship instormy sailing conditions, intended for testing new design solutions for promising ocean-going shipsand ships of unlimited ocean navigation, as well as organizing full-function simulators. The presentedtoolkit can be used by captains to select effective and safe sailing modes, as well as to train personnel.A modern computational experiment allows direct modeling of intense sea waves, which fullyrecreates the hydromechanics of external influences on the ship, and ensures its full positioningrelative to the crests of storm waves. Such experiments require the use of high-performance computingtechnology based on GPGPU, as well as distributed data preparation and processing. Parameters ofthree structures of real sea waves, including extremely high heights, are determined as the initialconditions for modeling. The ship also possesses real dynamic characteristics, and she is capable to goby arbitrary courses in relation to waves. The possibility of dynamically changing the parameters ofthe ship during the experiment is provided. It is required to assess the motion state in various cases ofship loading, including emergency. The most important feature of the software is a full-fledged threedimensional visualization of all storm waves, as well as the spatial position and trajectory of the shipand its parameters. A special experimental environment for engineering surveys for projected ships iscreated using the graphical tools of OpеnGL. This computer toolkit is considered within theframework of the concept of a virtual testbed.
10
Zhang, De-Qing, Jun-Feng Du, Zhi-Ming Yuan, Ming Zhang e Feng-Shen Zhu. "Hydrodynamic Modelling of Modularized Floating Photovoltaics Arrays". In ASME 2023 42nd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2023. http://dx.doi.org/10.1115/omae2023-102530.
Testo completoAbstract (sommario):
Abstract Large arrays of floating photovoltaics (FPV) are emerging to be an attractive solution to renewable energy production and ocean space utilization. FPV arrays are typically buoyed by hundreds of modularized floating bases arranged in ocean surface. The total performance of the FPV arrays is significantly affected by the hydrodynamic interactions between these individual floaters. As the size of the array increases, more time will be required to calculate the entire hydrodynamic properties. From the engineering point of view, it is a challenging task to fully consider the radiation interactions among the modularized FPV floaters. In fact, when the distance between two floating bodies is large enough, their interaction will gradually vanish. The present study developed a cut-off scheme to improve the computational efficiency while providing a reliable prediction of the interaction effects in engineering practice. A cut-off radius is introduced in this scheme to determine the coupling range in which the radiation hydrodynamic interactions should be considered. The cut-off radius is determined by three parameters, including the modular shape, wave frequency and accuracy requirement. Several arrays of rectangular FPV bases were taken as examples to show how to quantify the radiation interactions and find an optimal cut-off radius. The effect of wave direction, gap distance, and connection type were also investigated. The results from the validation case showed that the hydrodynamic interaction can be well predicted using the proposed cut-off scheme, while more than half of the computational time can be saved.
Rapporti di organizzazioni sul tema "Emergent hydrodynamics"
1
Bell, Gary, David Abraham, Nathan Clifton e Lamkin Kenneth. Wabash and Ohio River confluence hydraulic and sediment transport model investigation : a report for US Army Corps of Engineers, Louisville District. Engineer Research and Development Center (U.S.), marzo 2022. http://dx.doi.org/10.21079/11681/43441.
Testo completoAbstract (sommario):
Avulsions of the Wabash River in 2008 through 2011 at its confluence with the Ohio River resulted in significant shoaling in the Ohio River. This caused a re-alignment of the navigation channel and the need for frequent dredging. A two-dimensional numerical hydrodynamic model, Adaptive Hydraulics (AdH), was developed to simulate base (existing) conditions and then altered to simulate multiple alternative scenarios to address these sediment issues. The study was conducted in two phases, Phase 1 in 2013 – 2015 and Phase 2 in 2018 – 2020. Field data were collected and consisted of multi-beam bathymetric elevations, bed sediment samples, suspended sediment samples, and discharge and velocity measurements. The model hydrodynamic and sediment transport computations adequately replicated the water surface slope, flow splits, bed sediment gradations, and suspended sediment concentrations when compared with field data. Thus, it was shown to be dependable as a predictive tool. The alternative that produced the most desirable results included a combination of three level-crested emergent dikes on Wabash Island and four submerged dikes on the Illinois shore with a level crest from the bank to the tip of the dike. The selected alternative produced an improved sailing line while maintaining authorized channel depths.
2
Ginis, Isaac, Deborah Crowley, Peter Stempel e Amanda Babson. The impact of sea level rise during nor?easters in New England: Acadia National Park, Boston Harbor Islands, Boston National Historical Park, and Cape Cod National Seashore. National Park Service, 2024. http://dx.doi.org/10.36967/2304306.
Testo completoAbstract (sommario):
This study examines the potential impact of sea level rise (SLR) caused by climate change on the effects of extratropical cyclones, also known as nor?easters, in four New England coastal parks: Acadia National Park (ACAD), Boston Harbor Islands National Recreation Area (BOHA), Boston National Historical Park (BOST) and Cape Cod National Seashore (CACO). A multi-method approach is employed, including a literature review, observational data analysis, coupled hydrodynamic-wave numerical modeling, 3D visualizations, and communication of findings. The literature review examines previous studies of nor?easters and associated storm surges in New England and SLR projections across the study domain due to climate change. The observational data analysis evaluates the characteristics of nor?easters and their effects, providing a basis for validating the model. Numerical modeling is performed using the Advanced Circulation (ADCIRC) model, coupled with the Simulating Waves in the Nearshore (SWAN) model to simulate storm surges and waves. The model was validated against available observations and demonstrated its ability to simulate water levels, inland inundation, and wave heights in the study area with high accuracy. The validated model was used to simulate three powerful nor?easters (April 2007, January 2018, and March 2018) and each storm was simulated for three sea levels, (1) a baseline mean sea level representative of the year 2020, as well as with a (2) 1 ft of SLR and (3) 1 m of SLR. Analysis of the model output was used to assess the vulnerability of the parks to nor?easters by examining peak impacts in the park areas. Additional simulations were conducted to evaluate the role of waves in predicting peak water levels and the impact of inlet configurations on storm surges within coastal embayments behind the barrier beach systems in the southern Cape Cod region. The project developed maps, three-dimensional visualizations, and an interpretive film to assist the parks in planning for resource management, maintenance, emergency management, visitor access, safety, education, and outreach. These tools provide a better understanding of the potential impacts of nor?easters and SLR and enable the parks to better prepare for future storms.