Article
Mechanics
Josh Shelton, Philippe H. H. Trinh
Summary: There has been significant interest in studying water waves coupled with non-zero vorticity. In this study, we derive analytical approximations for free-surface waves generated by submerged point vortices at low Froude numbers. Our findings show that the presence of Stokes lines originating from a vortex leads to the formation of waves. Trapped waves can occur when multiple point vortices are present, and this phenomenon is observed for a countably infinite set of Froude numbers in the two-vortex problem.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Acoustics
Anna Katsiavria, Demetrios T. Papageorgiou
Summary: This article considers the stability of immiscible two-fluid Couette flows with slip present at the liquid-liquid interface. A nonlinear asymptotic theory is developed for a flow geometry in which a thin layer slips over a thick fluid layer. A nonlocal, nonlinear evolution equation is derived, valid at finite Reynolds numbers, slip lengths, viscosity and density ratios. The linear spectrum is calculated and it is shown that slip introduces dispersion, reducing instability or enhancing stability in geometries containing a thin layer.
Article
Mechanics
Jiyang Li, Zeng Liu, Shijun Liao, Alistair G. L. Borthwick
Summary: The study reveals the existence of two independent 'external' and 'internal' modes in a two-layer fluid, where exact harmonic resonance occurs when they share the same phase speed. The singularity or small divisor caused by resonant components is successfully eliminated using the homotopy analysis method, leading to convergent series solutions for steady-state interfacial wave groups with harmonic resonance. As the water depth varies, the energy carried by surface waves mirrors that carried by interface waves, showing a transfer of energy from shorter resonant components to longer primary ones as the upper layer depth increases.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Astronomy & Astrophysics
Noemi Kinga Zsamberger, Carmen M. Sanchez Montoya, Robert Erdelyi
Summary: Building on recent studies of the Kelvin-Helmholtz instability, this research investigates the influence of bulk flows on the propagation of MHD waves. Analytical and numerical analyses reveal that flow field asymmetry significantly affects the cutoff frequencies and stability of trapped MHD waves in slab configurations.
ASTROPHYSICAL JOURNAL
(2022)
Article
Mechanics
X. Guan, J-M Vanden-Broeck, Z. Wang
Summary: The study considers two-dimensional periodic interfacial gravity waves between two homogeneous fluids of finite depth. Highly accurate solutions are obtained using a boundary-integral-equation method coupled with Fourier expansions. The numerical results show excellent agreement with those obtained using a different scheme, exploring the global bifurcation mechanism and identifying three types of limiting wave profiles.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Nuclear Science & Technology
Y. Rivera, C. Berna, J. L. Munoz-Cobo, A. Escriva, Y. Cordova
Summary: This study experimentally investigates falling liquid films and downward cocurrent flows in rounded shape pipes, focusing on the characteristics of thin liquid layers and interfacial waves. Conductance probes are used to measure important variables and new correlations are developed based on dimensionless numbers. Comparisons with other studies are also included.
NUCLEAR ENGINEERING AND DESIGN
(2022)
Article
Mechanics
Gerardo Severino
Summary: The study investigates the dispersion mechanism in a porous formation with steady doublet-type flow, using spatial moments to quantify the process. A simple solution is obtained by adopting simplifying assumptions, showing that dispersion in doublet-type flow is significantly larger than in single line flow.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Engineering, Civil
Fabio Muraro, Giulio Dolcetti, Andrew Nichols, Simon J. Tait, Kirill Horoshenkov
Summary: In the last two decades, there has been a considerable increase in interest in the free-surface behaviour of gravity-driven shallow turbulent flows. Observing free-surface behaviour is believed to provide useful information about the hydrodynamic characteristics of the flow and enables remote monitoring of river flows. This paper reviews the state-of-art in this area, aiming to gather relevant information, use uniform terminology, and analyze gaps in knowledge about the linkages between free-surface behaviour and underlying hydrodynamic processes.
JOURNAL OF HYDRAULIC RESEARCH
(2021)
Article
Mechanics
Jeremie Vidal, David Cebron
Summary: Motivated by the modeling of rotating turbulence in planetary fluid layers, this study investigates precession-driven flows in ellipsoids under stress-free boundary conditions. The results show that viscosity affects the long-term evolution of angular momentum in triaxial geometries and axisymmetric ellipsoids when the mean rotation axis of the fluid is not the symmetry axis. By using stress-free boundary conditions, the study also explores non-viscous instabilities that are relevant for planetary applications but are often limited in experiments or simulations that use no-slip boundary conditions.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Acoustics
Harold Berjamin
Summary: Introduces simple strain-rate viscoelasticity models for isotropic soft solids. The constitutive equations consider finite strain, incompressibility, material frame-indifference, nonlinear elasticity, and viscous dissipation. Nonlinear viscous wave equation for shear strain is obtained exactly and corresponding one-way Burgers-type equations are derived through standard approximations. Analysis of travelling wave solutions reveals distinct solutions for these partial differential equations, with deviations amplified for non-arbitrarily small wave amplitudes. In the elastic limit, the one-way approximate wave equation can be connected to simple wave theory and shock wave theory, facilitating direct error measurements.
JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA
(2023)
Article
Geochemistry & Geophysics
Qiliang Mei, Tianjiang Wu, Chao Li, Xiaoying Zhou
Summary: Direct numerical simulation at the pore scale is a developing technique to investigate pore-scale flow behaviors in porous media. However, the interfacial tension of the two-phase interface becomes more important as the spatial scale decreases, affecting the accuracy and efficiency of numerical predictions. The proposed method using a constant velocity spiral to approximate the two-phase interface improves the accuracy of interfacial tension treatment and has strong engineering applications, as demonstrated through numerical simulations.
Review
Acoustics
Allan D. Pierce
Summary: The critique of Biot's theory of porous media highlights potential arbitrariness and the possibility of additional displacement fields in the model. The discussion focuses on the theoretical aspects at low frequencies and the flexibility in coefficients selection within the Biot low-frequency model.
JOURNAL OF THEORETICAL AND COMPUTATIONAL ACOUSTICS
(2021)
Article
Mechanics
Saswata Basak, Palas Kumar Farsoiya, Ratul Dasgupta
Summary: The study focuses on the mechanics of jet formation from capillary-gravity waves on a liquid pool surface in a cylindrical container, showing that linear theory is inadequate in describing the process. Nonlinear theory predicts energy transfer and numerical simulations reveal the jet originates from a small dimple at the wave trough. The theory qualitatively describes jet overshoot and liquid velocity/pressure fields, but does not capture the evolution of the dimple or the thinning of the jet neck leading to pinchoff.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Lin Chen, Biswajit Basu, Calin- Martin
Summary: In this study, the authors investigate the flow structure of periodic steady water waves with fixed relative mass flux propagating on rotational flows with piece-wise constant vorticity. Their findings reveal new insights into the characteristics of stagnation points in wave solutions along the global bifurcation diagram, as well as provide in-depth discussions on pressure distributions and particle trajectories beneath large-amplitude steady waves near stagnation. Additionally, the study expands on previous results regarding the amplitude and mass flux of steady water waves travelling on rotational flows with discontinuous vorticity.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Engineering, Civil
Pengxu Zou, Taeksang Kim, Jeremy D. Bricker, Wim S. J. Uijttewaal
Summary: In this study, different interfacial turbulence treatment methods were compared and it was found that both the SGDH model and the turbulence damping model can effectively improve turbulence production in free surface waves compared to the standard k-ε model. However, the SGDH model augmented turbulence kinetic energy (TKE) in the unstable stratification, leading to unphysical behavior in partially dispersed and separated flow regimes.
JOURNAL OF HYDRAULIC RESEARCH
(2023)
Article
Environmental Sciences
Melissa Latella, Fabio Sola, Carlo Camporeale
Summary: This study introduces a novel LiDAR algorithm for accurate individual tree detection in deciduous forests, with low sensitivity to parameter setup and applicability in low-density point cloud analysis. Additionally, the algorithm demonstrates potential for more complex tools in forest modeling and management.
Article
Mechanics
M. B. Bertagni, C. Camporeale
Summary: The study provides a hydrodynamic model for the formation of linear karren patterns, showing that transverse instability in the water-rock system leads to longitudinal channelization responsible for pattern formation. Rock solubility only affects the temporal scale of the instability, while rock inclination plays a minor role in pattern formation.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Engineering, Mechanical
Giulia Cardillo, Carlo Camporeale
Summary: The spinal cord is a complex tissue surrounded by cerebrospinal fluid in the subarachnoid space. A fully analytical fluid-structure interaction model based on porous elastic theory was proposed to study the dynamics of cerebrospinal fluid flow in the spinal cord. Deviations in physiological values and blood network permeability can significantly affect cerebrospinal fluid exchange, potentially contributing to the formation of syrinxes in severe neurological diseases.
JOURNAL OF FLUIDS AND STRUCTURES
(2021)
Review
Environmental Sciences
Jiri Jakubinsky, Marcela Prokopova, Pavel Raska, Luca Salvati, Nejc Bezak, Ondrej Cudlin, Pavel Cudlin, Jan Purkyt, Paolo Vezza, Carlo Camporeale, Jan Danek, Michal Pastor, Tomas Lepeska
Summary: Floodplains, shaped over a long time horizon by alluvial sediments, are flat and fertile lands that have become a focus of human society. Intensive land use is degrading their natural values and reducing ecosystem functions, particularly the ability to retain water and nutrients. Maintaining connectivity with rivers and adapting human activities are essential to preserve the floodplains' functions under conditions of global change.
WILEY INTERDISCIPLINARY REVIEWS-WATER
(2021)
Article
Mechanics
Carlo Camporeale, Fabio Cannamela, Claudio Canuto, Costantino Manes
Summary: This paper presents results from a linear stability analysis of turbulent depth-averaged open-channel flows with secondary currents, showing the existence of sinuous instability and the conditions required for its presence. The study suggests that VLSMs might be triggered by nonlinear mechanisms and LSMs could be governed by an outer-layer cycle.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Environmental Sciences
Luca Salerno, Alvaro Moreno-Martinez, Emma Izquierdo-Verdiguier, Nicholas Clinton, Annunziato Siviglia, Carlo Camporeale
Summary: This study provides a new framework for high-resolution mapping and monitoring of a large-scale tropical forest in the aquatic-terrestrial zone of an Amazon basin. The results indicate that increased hydrological stress leads to vegetation degradation, while areas no longer inundated experience encroachment of upland forests. Additionally, river regulation has an impact on the carbon cycling of riverine forests.
FRONTIERS IN ENVIRONMENTAL SCIENCE
(2022)
Article
Geosciences, Multidisciplinary
Andrea Columbu, Alessia Nannoni, Nives Grasso, Paolo Dabove, Adriano Fiorucci, Bartolomeo Vigna, Matteo B. Bertagni, Carlo Camporeale, Paolo Forti, Jo De Waele, Christoph Spotl
Summary: The study identifies a new type of wavy flowstones, demonstrating their formation process is closely related to climate conditions and can be used to reflect underground hydro-climatic conditions in caves. The deposition of these wavy flowstones only occurs during heavy rainfall events. These flowstones can serve as hydro-climatic indicators, providing crucial information for studying the long-term dynamics of intense precipitation events.
Article
Meteorology & Atmospheric Sciences
Aurelien Bosio, Pietro Salizzoni, Carlo Camporeale
Summary: This study examines the stochastic behavior of three popular low-order lumped models used in paleoclimate simulations using a unified mathematical framework. Through coherence resonance mechanism, the feedback between noise and the dynamical system reproduces the characteristic 100 ky pulsation of the Pleistocene climate in a wide range of model parameters. A stability analysis allows the separation of the deterministic-dominated region from the stochastic-dominated region in the parameter space.
Article
Environmental Sciences
Patricia M. Rodriguez-Gonzalez, Eleni Abraham, Francisca Aguiar, Andrea Andreoli, Ligita Balezentiene, Naim Berisha, Ivan Bernez, Michael Bruen, Daniel Bruno, Carlo Camporeale, Andraz Carni, Mila Chilikova-Lubomirova, Dov Corenblit, Renata Custerevska, Tanya Doody, Judy England, Andre Evette, Robert Francis, Virginia Garofano-Gomez, Marta Gonzalez del Tanago, Yasar Selman Gultekin, Florian Guyard, Seppo Hellsten, Georgi Hinkov, Jiri Jakubinsky, Philippe Janssen, Roland Jansson, Jochem Kail, Emine Keles, Mary Kelly-Quinn, Anna Kidova, Timea Kiss, Mart Kulvik, Nicola La Porta, Marianne Laslier, Melissa Latella, Stefan Lorenz, Dejan Mandzukovski, Paraskevi Manolaki, Vanesa Martinez-Fernandez, David Merritt, Adrien Michez, Jelena Milovanovic, Tomasz Okruszko, Eva Papastergiadou, Ellis Penning, Remigiusz Pielech, Emilio Politti, Ana Portela, Tenna Riis, Zeljko Skvorc, Michal Slezak, Barbara Stammel, John Stella, Danijela Stesevic, Vladimir Stupar, Olga Tammeorg, Priit Tammeorg, Therese Moe Fosholt, Gorazd Urbanic, Marc Villar, Ioannis Vogiatzakis, Paul Vrchovsky, Rasoul Yousefpour, Peggy Zinke, Tzvetan Zlatanov, Simon Dufour
Summary: This article identifies and discusses 10 key challenges in riparian vegetation science and management improvement, providing guidance for future research in this field.
WILEY INTERDISCIPLINARY REVIEWS-WATER
(2022)
Article
Environmental Sciences
M. Latella, T. Raimondo, E. Belcore, L. Salerno, C. Camporeale
Summary: The role of vegetation in supporting life on Earth is well-known, but the relevance of riparian corridors has been overlooked for a long time. This study demonstrates the integration of LiDAR datasets and field measurements to estimate biomass and generate accurate biomass maps. A case study of the Orco river in northwest Italy is presented, showing the successful application of the technique in estimating riparian biomass and understanding the natural and anthropogenic processes in the area.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Article
Multidisciplinary Sciences
Eliza J. Dawson, Dustin M. Schroeder, Winnie Chu, Elisa Mantelli, Helene Seroussi
Summary: This study investigates how warmer basal temperatures could affect the mass balance of the Antarctic ice sheet using numerical ice sheet modeling. The results show increased mass loss in response to idealized basal thawing experiments. Notably, frozen-bed patches in certain regions of East Antarctica may currently be sustaining the ice configuration, but with less than 5 degrees of basal warming, these patches could begin to thaw and contribute to new loci of mass loss.
NATURE COMMUNICATIONS
(2022)
Editorial Material
Geosciences, Multidisciplinary
Shashank Kumar Anand, Sara Bonetti, Carlo Camporeale, Milad Hooshyar, Amilcare Porporato
Summary: This comment clarifies the misunderstandings in Litwin et al.'s interpretation of the previous works by Bonetti et al., specifically regarding the definition of specific contributing area and the impact of boundary conditions on solutions of the landscape evolution model.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2022)
Article
Geosciences, Multidisciplinary
Shashank Kumar Anand, Sara Bonetti, Carlo Camporeale, Amilcare Porporato
Summary: This article presents a linear stability theory for incipient valley formation in mountainous landscapes, and validates the theory through numerical simulations and topographic data.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2022)
Article
Multidisciplinary Sciences
Luca Salerno, Paolo Vezza, Paolo Perona, Carlo Camporeale
Summary: This study analyzes the eco-morphodynamic activity of large tropical rivers in South and Central America to quantify the carbon flux from riparian vegetation to inland waters. Satellite data of the largest rivers in the Neotropics from 2000 to 2019 were used, and a highly efficient Carbon Pump mechanism was developed. This mechanism alone accounts for 8.9 million tons/year of carbon mobilization in these tropical rivers. Signatures of fluvial eco-morphological activity providing proxies for carbon mobilization capability are identified, and the impact of river migration on carbon intensity of planned hydroelectric dams in the Neotropics is discussed.
SCIENTIFIC REPORTS
(2023)
Article
Physics, Fluids & Plasmas
Federica Montana, Carlo Camporeale, Amilcare Porporato, Lamberto Rondoni
Summary: Active particles that self-propel by transforming energy into mechanical motion are the focus of research in mathematics, physics, and chemistry. In this study, we examine the dynamics of non-spherical inertial active particles moving in a harmonic potential, taking into account the role of eccentricity. We compare overdamped and underdamped models for elliptical particles and find that increasing eccentricity leads to substantial differences between the two dynamics.