Hydrodynamics - Science topic

This paper deals with the bow optimization of a RoRo cargo ship to reduce full-scale resistance in calm water. It employs a multi-fidelity surrogate model integrating high-and low-fidelity potential flow solver solutions. Adaptive sampling, driven by a dynamic lower confidence bound strategy, determines both new sample locations and fidelity levels...

Multiple floating structures offer a versatile solution for offshore engineering. However, these systems are inherently complex due to hydrodynamic interactions and intricate connections between structures and moorings. This study aims to develop a coupled time-domain model for multiple floating structures, and to demonstrate its application to cat...

The book describes effective analytical methods for finding exact solutions to nonlinear differential equations of mathematical physics and other partial differential equations and also demonstrates the practical applications of these methods. It covers the methods of generalized separation of variables, methods of functional separation of variable...

The electrochemical dissolution of carbon steel exposed to aqueous carbonates stands as one of the main causes for the deterioration of carbon capture, utilisation and storage facilities, pipelines, hydrocarbon refining equipment and reinforced concrete structures. To unlock the full potential of carbon capture applications and ensure the structura...

Research on multi-body hydrodynamics is of major importance within the field of ocean engineering, and it is facing rapid development mainly due to the latest technologies in Offshore Renewable Energies and Very Large Floating Structures. Given the high level of complexity intrinsic to those systems, it also faces a need for efficient analysis meth...

The Callaway approximation to the linearized Peierls-Boltzmann equation (LPBE) is often used to describe the steady-state and the transient phonon dynamics in ultrahigh thermal conductivity (κ) materials, particularly under cryogenic conditions, due to its low computational cost relative to the full LPBE solution. However, the predictive capability...

This work focuses on the hydrodynamic investigation of a RoRo cargo ship through full-scale RANS (Reynolds-Averaged Navier-Stokes) simulations in calm water conditions. Conducted as part of the EU-funded Retrofit55 project, the study aims to validate the bow optimization process based on a multi-fidelity surro-gate model that integrates high-fideli...

The existence of supermassive black holes (SMBHs) with masses ∼10⁹ M☉ at redshifts z > 6 challenges conventional cosmological structure formation. Standard scenarios relying on Population III remnants or direct collapse models face severe constraints regarding timescales and accretion efficiency. This paper proposes a novel mechanism wherein locali...

The Jakobsson–Floberg–Olsson (JFO) cavitation models proposed by different authors have subtle differences in governing equations and unknowns, which often leads to confusion. To address this, this study introduces a general lubrication model to reformulate them. The general lubrication model was developed from the perspective of gas–liquid two-pha...

A computational study is presented that examines the hydrodynamic ordering of soft-particle suspensions within rectangular channels undergoing both steady and oscillatory flow. In these conditions, particles assemble into one-dimensional train-like...

The increasing flood risk in urban areas, driven by rising urbanization and climate change, underscores the need for accurate representation of buildings and urban features in flood hydrodynamic models. This study investigates the impact of different building representation techniques on flood hydrodynamic and impact modeling, using the 2021 flood...

Although the X-ray spectra of Seyfert 1 galaxies exhibit absorption lines of He-like iron and H-like iron at blueshifted velocities of approximately 500 km s ⁻¹ , the physical origin of these absorption lines remains uncertain. In this study, we performed X-ray radiative transfer based on the subparsec-scale thermally driven outflows. The initial s...

By employing the Gubser solutions of causal relativistic second-order Israel–Stewart hydrodynamics, we study the thermal dilepton production from heavy-ion collisions, considering the transverse expansion of the viscous hot QCD medium along with longitudinal boost-invariance. We analyze the evolution of the temperature and shear stress profiles of...

The Qaidam Basin is the largest basin on the northeastern Tibetan Plateau, where the Cenozoic sediments attain thicknesses up to over 10 km. These sediments record the growth process of the plateau and the paleoclimatic changes, and thus attract wide attention. Previous studies focused on describing these strata and qualitatively determining their...

Bridge piers in deep reservoirs with canyon terrain boundaries are subject to complex hydrodynamic effects during earthquakes. In this study, a framework with added mass is adopted to calculate the effects of canyon terrain boundaries. This approach is demonstrated to be effective and accurate after the results from the fluid–structure interaction...

Planing craft, as a type of high-performance ship, is mainly supported by hydrodynamic lift. When this type of ship navigates in waves, external disturbance easily leads to motion in big amplitude. In this paper, the forward navigation problem of a planing hull is transformed into the water entry slamming problem of a two-dimensional section based...

Background/Objectives: Treatment options for androgenic alopecia are still very limited and lack long-term efficacy. Dutasteride (DUT) has gained interest as a potent inhibitor of 5α-reductase, allowing for spaced applications, but DUT oral intake can cause serious adverse effects. Herein, we developed, characterized, and assessed the potential of...

This study presents an Early Warning System (EWS) for coastal flooding that integrates wind, wave, and sea level forecasts which are validated using in-situ records. The system employs the SWAN spectral wave model to simulate nearshore hydrodynamics while an empirical approach is used to assess Total Watel Level (TWL) exceedances over a user-define...

The time evolution of the contact parameter provides key insights into correlation dynamics in ultracold gases. However, most contact measurements to date have focused on equilibrium systems or slow, global dynamics. Here, we demonstrate that projecting a unitary Fermi gas onto a low-lying dimer state enables rapid probing of the contact. Using $^{...

Floating Offshore Wind Turbines (FOWTs) can exploit the high energy density experienced in offshore environments, with turbines now reaching up to 15 MW in size. However, given the larger size of these turbines and the environmental conditions they are exposed to, there remain significant challenges in motion stabilization. To overcome these challe...

The motion of several plates in an inviscid and incompressible fluid is studied numerically using a vortex sheet model. Two to four plates are initially placed in line, separated by a specified distance, and actuated in the vertical direction with a prescribed oscillatory heaving motion. The vertical motion induces the plates’ horizontal accelerati...

The dynamics of wall-mounted flexible structures, such as aquatic vegetation, is essential for analysing collective behaviours, flow distributions and vortex formation across different scales. To accurately model these structures under various flow conditions, we develop a novel numerical method that couples the immersed boundary method (IBM) with...

Hydrodynamic models are required to predict the power produced by a tidal array and the impact on the surrounding environment. The influence of common model inputs to layout optimisation are investigated herein. This is achieved using a shallow water equation based tidal array modelling framework, Thetis, coupled with a low cost analytical wake mod...

Solid grains immersed in a carrier fluid can be found in many fields of engineering and geophysics. Considering single grains and especially spheroids immersed in a fluid under shear flow conditions, the rotational motion of these grains leads to the so-called Jeffery orbits. Considering both a Newtonian and non-Newtonian (Bingham–Papanastasiou) fl...

The design of moored floating wave energy converters (WECs) must take into account extreme responses and mooring line loads in order to ensure their survival and continued wave power generation in the ocean environment. This study focuses on Mocean Energy’s Blue Horizon C1 hinged raft WEC and aims to provide a better understanding of its hydrodynam...

The design and analysis of a new wave actuator for boats is presented in this paper. The wave actuator is installed beneath the boat hull and converts the hydrodynamic forces generated by rising waves on the boat into translational thrusting forces. The wave actuator consists of a flexible water tank, revolving springs, and inlet/outlet nozzles to...

We develop Hamiltonian mechanics on Aristotelian manifolds, which lack local boost symmetry and admit absolute time and space structures. We construct invariant phase space dynamics, define free Hamiltonians, and establish a generalized Liouville theorem. Conserved quantities are identified via lifted Killing vectors. Extending to kinetic theory, w...

Computational fluid dynamics (CFD) models have been widely used to evaluate the hydrodynamic and gas exchange performances of oxygenators, which are crucial in supporting patients with lung diseases or failure. However, while CFD models have been effective in analyzing oxygen transfer, they have not adequately addressed the experimentally demonstra...

Benefitting from the direct modeling of physical laws in a discretized space and the automatic decomposition of hydrodynamic waves and particles, the unified gas-kinetic wave-particle (UGKWP) method offers notable advantages in various multiscale physics, such as hypersonic flow, plasma transport and radiation transport. Aiming at achieving a more...

The work is devoted to the study of the hydrodynamic grinding of industrial hemp in a "jet-barrier" type plant in order to optimize the process for the production of paper products. The purpose of the study is to determine the influence of the circumferential rotation speed of a movable barrier and its structure on the paper-forming properties of a...

Recent hydrodynamical simulations of isolated barred disc galaxies have suggested a structural change in the distribution of the interstellar medium (ISM) around a stellar mass M$_{*}$ of $10^{10}$ M$_{\odot}$. In the higher-mass regime (M$_{*} \geq 10^{10}$ M$_{\odot}$), we observe the formation of a central gas and stellar disc with a typical siz...

The TIDE Research Hub is working with industry partners to develop a large database of geological and geotechnical data from the NorthWest Shelf of Australia (NWS), one of the largest carbonate-dominated shelves in the world, to better understand the geotechnical behaviour of carbonate sediments. Within this framework, this paper investigates the p...

We derive a self-consistent hydrodynamic theory of coupled binary-fluid-surfactant systems from the underlying microscopic physics using Rayleigh's variational principle. At the microscopic level, surfactant molecules are modelled as dumbbells that exert forces and torques on the fluid and interface while undergoing Brownian motion. We obtain the o...

In this paper, we study an integrable system with the self-consistent potentials called the Nurshuak-Tolkynay-Myrzakulov (NTM) system. This system is of great importance in the theory of integrable nonlinear equations, since this system describes the dynamics of nonlinear wave processes in various fields of physics, such as hydrodynamics, optics, q...

This paper deals with the condensation of liquid droplets on hydrophobic and hydrophilic surfaces. A stochastic mesoscale model based on the theory of fluctuating hydrodynamics and the thermodynamics of a diffuse interface approach shows how direct simulation of the vapour-liquid transition from the nucleation process to droplet hydrodynamics can b...

The shock Hugoniot of heterogenous mixtures of discrete particles has been experimentally investigated for porous agglomerates and fluids, while the study of full-density solids has been primarily limited to compressed powders and high-dimensional composites. By dispersing ceria nanoparticles in a polyethylene matrix, we are able to examine the hyd...

This study investigates the influence of chirality, viscous effects, and confinement geometry on the flow dynamics and defect structures of cholesteric liquid crystals (CLCs) using numerical simulations. As chiral strength increases, $\pi$-twist defects form at low chirality and progressively organize into hexagonal domains resembling blue phase--l...

Atomic hydrogen constitutes the gas reservoir from which molecular gas and star formation in galaxies emerges. However, the weakness of the line means it has been difficult to directly detect in all but the very local Universe. Here we present results from the first search using the MeerKAT International Tiered Extragalactic Exploration (MIGHTEE) S...

Ultracold quantum-gas mixtures of fermionic atoms with resonant control of interactions offer a unique test-bed to explore few- and many-body quantum states with unconventional properties. The emergence of such strongly correlated systems, for instance, symmetry-broken superfluids, is usually accompanied by hydrodynamic collective behavior. Thus ex...

Atomic force microscopy (AFM)-based single-molecule force spectroscopy (SMFS) enables the characterization of individual biological molecules through the application of mechanical force. The spatiotemporal resolution of such measurements depends greatly on the AFM cantilever that is used, specifically its stiffness, hydrodynamic drag, and material...

The settling of highly elastic non-Brownian closed fibres (called loops) under gravity in a viscous fluid is investigated numerically. The loops are represented using a bead–spring model with harmonic bending potential and finitely extensible nonlinear elastic stretching potential. Numerical solutions to the Stokes equations are obtained with the u...

Examining the spatiotemporal coherence structures constitutes a significant issue in investigating the hydrodynamics of spouted fluidized beds. This study employed data-driven methods of proper orthogonal decomposition (POD) and dynamic mode decomposition (DMD) to identify and analyze the coherent structures presented in a spouted fluidized bed. It...

We analytically compute the low-temperature charge correlators in near-extremal black holes with a planar horizon and an infrared $\mathrm{AdS}_2\times \Bbb{R}^2$ extremal geometry, finding excellent agreement with numerical calculations. The analytical result consistently describes the crossover between the hydrodynamic diffusive regime at low fre...

A submerged floating tunnel (SFT) is a new form of underwater transportation that can be used to cross the channel. It comprises a tunnel tube, a mooring system, and a barge structure. In this paper, the selection of anchor cable layout for oval cross-section SFT is studied according to the common sea conditions in the straits, and the variation ru...

Statistical studies of protoplanetary disks and exoplanet populations often exhibit a "missing mass" problem, where observed dust masses in (sub-)millimeter surveys are significantly lower than expected when compared to the mass of evolved exoplanetary systems. We investigate how the streaming instability and subsequent planetesimal formation in pr...

Experiments of isochoric heating by protons of solid material were recently performed at LULI laser facilities. In these experiments, protons, produced from target normal sheath acceleration (TNSA) of Au foil with the PICO2000 laser, deposit their energy into an aluminum or copper foil initially at room temperature and solid density. The heated mat...

We consider the non-linear dynamics governing the break-up of a two-dimensional strip of active chiral fluid. We observe that the strip thickness goes to zero at the pinch off points as a power law in finite time. Using slender body theory combined with a scaling analysis, we identify a new class of scaling exponents and scaling functions character...

We perform two-dimensional, multi-group radiation hydrodynamic simulations to explore the observational properties of a solar-like star colliding with an accretion disk around a supermassive black hole at separation of $\sim 100$ gravitational radii. We find that the star-disk collision produces ejecta on both sides of the disk. As the ejecta expan...

Integrable systems feature an infinite number of conserved charges and on hydrodynamic scales are described by generalised hydrodynamics (GHD). This description breaks down when the integrability is weakly broken and sufficiently large space-time-scales are probed. The emergent hydrodynamics depends then on the charges conserved by the perturbation...

Elongated particles in dense systems often exhibit alignment due to volume exclusion interactions, leading to packing configurations. Traditional models of collective dynamics typically impose this alignment phenomenologically, neglecting the influence of volume exclusion on particle positions. In this paper, we derive nematic alignment from an ani...

This study investigates the hydrodynamic behavior of oblate ellipsoidal particles immersed in a uniform flow, focusing on their flow resistance coefficients, including drag, lift, and pitching torque. Using advanced particle-resolved direct numerical simulations (PR-DNS), the research explores fluid-particle interactions across a range of aspect ra...

This article presents a collaborative research campaign under the OC7 project on refining the engineering modeling approach for hydrodynamic viscous drag and damping on floating wind platforms, focusing on the adjustment of hydrodynamic drag and damping coefficients for different sea states. The participant simulation results show significant impro...

The filamentation instability of a current-driven collisional dusty plasma in the dust-acoustic frequency region is investigated using the hydrodynamic theory and taking into account dust charge fluctuations. The effect of ion drag force on the development of this instability is studied. The results demonstrate that the filamentary mode appears at...

The granulometric classification of soils is crucial in various scientific disciplines, including geotechnics, agronomy, geology, hydrogeology, and atmospheric studies. This mini review compares 15 of the most widely used granulometric classification methodologies for soils, sediments, and wastes over the last seventy years. The study utilizes 244...

Helioseismology has revolutionized our understanding of the Sun by analyzing its global oscillation modes. However, the solar core remains elusive, limiting a full understanding of its evolution. In this work, we study a previously unnoticed global oscillation mode of the Sun using a fully compressible, hydrodynamical simulation of the solar interi...

Holographic D-brane constructions, governed by the Dirac-Born-Infeld (DBI) action, play a central role in the AdS/CFT correspondence, particularly in applications to quantum chromodynamics and condensed matter systems. In this work, we demonstrate how to equip these bottom-up holographic models with dynamical boundary gauge fields, thereby introduc...

The path tracking control of autonomous underwater vehicle (AUV) in high-speed marine applications faces significant challenges due to complex oceanic environment, nonlinear coupled dynamics, uncertain hydrodynamic coefficients, and payload variation. The conventional methods like proportional–integral–derivative and sliding mode control struggle t...

The consistent description of kinetic and hydrodynamic processes is applied to the study of ion transport processes in the ionic solution-porous medium system. A system of equations is obtained for the nonequilibrium single-ion distribution function, the nonequilibrium average value of the energy density of the interaction of solution ions, and the...

Mixing-induced reactions play an important role in a wide range of porous media processes. Recent advances have shown that fluid flow through porous media leads to chaotic advection at the pore scale. However, how this impacts Darcy-scale reaction rates is unknown. Here, we measure the reaction rates in steady mixing fronts using a chemiluminescenc...

We model the effect of resonances between time-varying perturbative forces and the epi-cyclical motion of eccentric binaries in the gravitational wave (GW) driven regime. These induce secular drifts in the orbital elements which are reflected in a dephasing of the binary's GW signal, derived here systematically. The resulting dephasing prescription...

Dunes in natural marine environments are subject to various complex and unsteady hydrodynamic forcings. In shallow waters and intertidal environments in particular, subaqueous dunes are strongly influenced by waves which combine with unidirectional or reversing currents. Understanding and predicting their morphology and dynamics is crucial because...

A numerical investigation is conducted to characterize the interaction dynamics between planar incident shock waves (Mach numbers ranging from 1.21 to 2.00) and a cylindrical SF6 heavy gas column embedded in ambient air, focusing on Richtmyer–Meshkov instability (RMI) development, interfacial scale evolution, and vorticity-driven material transport...

The cambered deflectors in aquacultural facilities are applied to enhance hydro-dynamic efficiencies or enable flow fields to be fully developed. Given the anticipated improvements with the bio-inspired profiles or tandem configurations, the hydrodynamics of cambered deflectors with the above features are investigated at Re = 1 × 10 5. The relation...

Separate spin evolution quantum hydrodynamic (SSE-QHD) model has led to a new type of spin-electron acoustic waves (SEAWs). In the present work by employing the (SSE-QHD) model we investigate the periodic structures of obliquely propagating SEAW. The nonlinear periodic wave solutions are derived by using reductive perturbation method. The periodic...

Improving the reliability and durability of internal combustion engines in marine vessels is a complex issue. The vibrations generated in these engines significantly affect their proper operation. One of the current research challenges is identifying effective methods to reduce, among other things, torsional vibrations generated within the crank-pi...

We analyze the dynamics of low-mass black hole (BH) seeds in the high-redshift ($z\gtrsim5$) Universe using a suite of $[4.5~\mathrm{Mpc}]^3$ and $[9~\mathrm{Mpc}]^3$ BRAHMA cosmological hydrodynamic simulations. The simulations form seeds with mass $M_{\mathrm{seed}}=2.2\times10^3~M_{\odot}$ in halos that exceed critical thresholds of dense & meta...

We study the fractional coupled Higgs system through new solitary and soliton wave solutions achieved by using the Riccati-Bernoulli sub-ODE method and Bäcklund transformation. The methods produce several kinds of exact wave solutions together with periodically perturbed structures that reveal the dynamic system behavior under fractional-order infl...

Flood inundation modelling antecedent to efficient flood management is often constrained by the limited availability of in-situ hydro-meteorological observations. Reanalysis datasets, such as ERA5, offer a promising alternative by providing continuous and high-resolution spatiotemporal information. While ERA5 has been widely recognized for hydrolog...

We systematically investigate the ground state and dynamics of spinor Bose-Einstein condensates subject to a position-dependent detuning. This detuning induces three related quantities-a synthetic magnetic field, an angular velocity, and an angular momentum-which, due to trap anisotropy, may point in different directions. When the dipole frequencie...

We study the collective oscillations of spin-orbit-coupled Bose-Einstein condensates in the presence of position-dependent detuning. Specifically, we explore the quadrupole modes of the system using both numerical and analytical approaches based on the Gross-Pitaevskii equation and hydrodynamic theory. Due to spin-orbit coupling and the synthetic m...

Cylindrical structures used in offshore energy production systems are subjected to various stresses and loads (waves and currents). Understanding the interactions between these cylindrical structures and bedforms is critical, as rapid changes in the bathymetry can expose and damage pile foundations and cables. The impact of a vertical cylinder on a...

This study employs the lattice Boltzmann method to investigate hydrodynamic forces and torque on a wall-attached prolate spheroidal particle in linear shear flow. The effects of incidence angle, pitch angle, and particle aspect ratio on drag, lift, and torque coefficients under finite particle Reynolds numbers are investigated. When the pitch angle...

Fluids at supercritical pressures exhibit large variations in density near the pseudo-critical line, such that buoyancy plays a crucial role in their fluid dynamics. Here, we experimentally investigate heat transfer and turbulence in horizontal hydrodynamically developed channel flows of carbon dioxide at $88.5$ bar and $32.6\,^{\circ }\rm C$ , hea...

Traditional surface cleaning methods often suffer from drawbacks such as chemical harshness, potential for surface damage, and high energy consumption. This study investigates an alternative approach: acoustic-driven surface cleaning using millimeter-sized bubbles excited at low, sub-cavitation frequencies. We identify and characterize a distinct t...

We present a joint analysis of weak gravitational lensing (shear) data obtained from the first three years of observations by the Dark Energy Survey and thermal Sunyaev-Zel'dovich (tSZ) effect measurements from a combination of Atacama Cosmology Telescope (ACT) and Planck data. A combined analysis of shear (which traces the projected mass) with the...

Dam breaching is a time dependent and nonlinear phenomenon. Water-soil interaction together with non-homogeneous and other specific material properties for each dam structure lead to a difficulty of accurately utilizing for modelling processes which involves in breach development. Hydrodynamics effects, sediment transport mechanics, and geotechnica...

Dam breaching is a time dependent and nonlinear phenomenon. Water-soil interaction together with non-homogeneous and other specific material properties for each dam structure lead to a difficulty of accurately utilizing for modelling processes which involves in breach development. Hydrodynamics effects, sediment transport mechanics, and geotechnica...

The application of femtosecond laser-induced periodic surface structures (LIPSSs) is often hindered by unsatisfactory uniformity and homogeneous morphology. In this study, a high-fidelity recording technique is introduced for imprinting diverse two-dimensional (2D) LIPSSs on silicon surfaces via the two-step femtosecond laser exposure and chemical...

The accurate modeling of particle motion in viscous fluids at high Reynolds numbers remains a fundamental challenge, particularly under unsteady flow conditions where nonlinear effects dominate. This study introduces a revised unsteady drag formulation, extending its applicability beyond previous studies. By integrating classical solutions of the N...

Microannular rotating bed (MARB) is a newly designed reactor that integrates high‐gravity fields and microscale effects to enable efficient liquid mixing. This study systematically investigated the hydrodynamic and liquid–liquid dispersion characteristics of the MARB, including residence time distribution, liquid holdup, energy dissipation rate, an...

The supersonic wake of a circular cylinder in Mach 3 flow was studied through spectral proper orthogonal decomposition (SPOD) of high-speed focussing schlieren datasets. A wavenumber decomposition of the SPOD eigenvectors was found to be an effective tool for isolating imaging artefacts from the flow features, resulting in a clearer interpretation...

We investigate the influence of a background dark energy (DE) fluid on the equation of state (EOS) of neutron stars, treating dark energy as a dynamical fluid with a barotropic equation of state p de =wρ de permeating spacetime. Incorporating DE within the Tolman-Oppenheimer-Volkoff (TOV) framework, we derive modified hydrostatic equilibrium equati...

In this paper, a quantum hydrodynamic system for particle density, current density, energy density, and electrostatic potential, coupled with a Poisson equation, is studied in spatial one‐dimensional real line. First, the existence and uniqueness of the stationary solution are proved in an appropriate Sobolev space. Then the semiclassical limit is...

We investigate the Brownian motion of isolated snowman-shaped particles consisting of pairs of large and small spheres by video microscopy. Our observations reveal that the particle exhibits varying degrees of anisotropic translational diffusion depending on the reference point used for tracking. In particular, when tracking the snowman’s geometric...

Coarse-graining complex molecular systems to lower-dimensional reaction coordinates is a powerful approach for capturing their effective dynamics. The generalized Langevin equation (GLE) provides an exact framework for modeling coarse-grained dynamics, and is particularly useful when non-Markovian effects are significant. While one-dimensional GLE...

Relativistic hydrodynamics provides a solid framework for evolving matter and energy in a wide variety of phenomena. Nevertheless, the inclusion of dissipative effects in realistic scenarios through causal, stable, and well-posed theories still constitutes an open problem. In this paper, we point out that the first-order reduction originally propos...